Posts Tagged ‘human genome’

CRISPR cuts turn gels into biological watchdogs, Volume 2 (Volume Two: Latest in Genomics Methodologies for Therapeutics: Gene Editing, NGS and BioInformatics, Simulations and the Genome Ontology), Part 2: CRISPR for Gene Editing and DNA Repair

Update 6/11/2020

CRISPR-IL used to develop next-gen genome editing products

  1. Haifa-based Pluristem Therapeutics is a regenerative medicine company that plans to develop next-generation multi-species genome editing products for human, plant and animal DNA that could improve work done in the pharma, agriculture and aquaculture industries.
  2. The CRISPR-IL consortium includes Sheba Medical Center and Schneider Children’s Medical Center, Bar-Ilan University, Ben-Gurion University of the Negev, Hebrew University of Jerusalem, the Weizmann Institute of Science, IDC Herzliya and Tel-Aviv University.
  3. This consortium is also joined by Pluristem Therapeutics, which plans to bring together a team of multi-disciplinary experts to develop artificial intelligence  based end-to-end genome-editing solutions.
  4. The genome editing product designed by Pluristerm should improve existing technology.
  5. The project also includes “the computational design of on-target DNA modification, with minimal accidental, off-target modifications, improve modification efficiency.
  6. The product provides an accurate measuring tool to ensure the desired modification.



CRISPR cuts turn gels into biological watchdogs

Reporter: Irina Robu, PhD

Genome editing if of significant interest in the prevention and treatment of human diseases including single-gene disorders such as cystic fibrosis, hemophilia and sickle cell disease. It also shows great promise for the prevention and treatment of diseases such as cancer, heart disease, mental illness and human immunodeficiency virus infection. However, ethical concerns arise when genome editing, using technologies such as CRISPR-Cas9 is used to alter human genomes.

James Collins, bioengineer at MIT and his team worked with water-filled polymers that are held together by strands of DNA, known as DNA hydrogels. To alter the properties of these materials, these scientists turned to a form of CRISPR that uses a DNA-snipping enzyme called Cas12a, which can be programed to recognize a specific DNA sequence. The enzyme then cuts its target DNA strand, then severs single strands of DNA nearby. This property lets scientists to build a series of CRISPR-controlled hydrogels encapsulating a target DNA sequence and single strands of DNA, which break up after Cas12a identifies the target sequence in a stimulus. The break-up of the single DNA strands activates the hydrogels to change shape or completely dissolve, releasing a payload.

According to Collins and his team, the programmed hydrogels will release enzymes, small molecules and human cells as part of a smart therapy in response to stimuli. However, in order to make it a smart therapeutic, the researchers in collaboration with Dan Luo, bioengineer at Cornell University placed the CRISPR- controlled hydrogels into electric circuits. The circuit is switched off in response to the detection of the genetic material of harmful pathogens such as Ebola virus and methicillin-resistant Staphylococcus aureus. The team used these hydrogels to develop a prototype diagnostic tool that sends a wireless signal to identify Ebola in lab samples.

Yet, it is evident that these CRISPR-controlled hydrogels show great potential for the prevention and treatment of diseases.






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Detecting Multiple Types of Cancer With a Single Blood Test

Reporter and Curator: Irina Robu, PhD

Monitoring cancer patients and evaluating their response to treatment can sometimes involve invasive procedures, including surgery.

The liquid biopsies have become something of a Holy Grail in cancer treatment among physicians, researchers and companies gambling big on the technology. Liquid biopsies, unlike traditional biopsies involving invasive surgery — rely on an ordinary blood draw. Developments in sequencing the human genome, permitting researchers to detect genetic mutations of cancers, have made the tests conceivable. Some 38 companies in the US alone are working on liquid biopsies by trying to analyze blood for fragments of DNA shed by dying tumor cells.

Premature research on the liquid biopsy has concentrated profoundly on patients with later-stage cancers who have suffered treatments, including chemotherapy, radiation, surgery, immunotherapy or drugs that target molecules involved in the growth, progression and spread of cancer. For cancer patients undergoing treatment, liquid biopsies could spare them some of the painful, expensive and risky tissue tumor biopsies and reduce reliance on CT scans. The tests can rapidly evaluate the efficacy of surgery or other treatment, while old-style biopsies and CT scans can still remain inconclusive as a result of scar tissue near the tumor site.

As recently as a few years ago, the liquid biopsies were hardly used except in research. At the moment, thousands of the tests are being used in clinical practices in the United States and abroad, including at the M.D. Anderson Cancer Center in Houston; the University of California, San Diego; the University of California, San Francisco; the Duke Cancer Institute and several other cancer centers.

With patients for whom physicians cannot get a tissue biopsy, the liquid biopsy could prove a safe and effective alternative that could help determine whether treatment is helping eradicate the cancer. A startup, Miroculus developed a cheap, open source device that can test blood for several types of cancer at once. The platform, called Miriam finds cancer by extracting RNA from blood and spreading it across plates that look at specific type of mRNA. The technology is then hooked up at a smartphone which sends the information to an online database and compares the microRNA found in the patient’s blood to known patterns indicating different type of cancers in the early stage and can reduce unnecessary cancer screenings.

Nevertheless, experts warn that more studies are essential to regulate the accuracy of the test, exactly which cancers it can detect, at what stages and whether it improves care or survival rates.




Other related articles published in this Open Access Online Scientific Publishing Journal include the following:

Liquid Biopsy Chip detects an array of metastatic cancer cell markers in blood – R&D @Worcester Polytechnic Institute, Micro and Nanotechnology Lab

Reporters: Tilda Barliya, PhD and Aviva Lev-Ari, PhD, RN


Liquid Biopsy Assay May Predict Drug Resistance

Curator: Larry H. Bernstein, MD, FCAP


One blood sample can be tested for a comprehensive array of cancer cell biomarkers: R&D at WPI

Curator: Marzan Khan, B.Sc




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Sequence the Human Genome, Volume 2 (Volume Two: Latest in Genomics Methodologies for Therapeutics: Gene Editing, NGS and BioInformatics, Simulations and the Genome Ontology), Part 1: Next Generation Sequencing (NGS)

Sequence the Human Genome

Curator: Larry H Bernstein, MD, FCAP



Geneticist Craig Venter helped sequence the human genome. Now he wants yours.

By CARL ZIMMER   NOVEMBER 5, 2015   http://www.statnews.com/2015/11/05/geneticist-craig-venter-helped-sequence-the-human-genome-now-he-wants-yours/

If you enter Health Nucleus, a new facility in San Diego cofounded by J. Craig Venter, one of the world’s best-known living scientists, you will get a telling glimpse into the state of medical science in 2015.

Your entire genome will be sequenced with extraordinary resolution and accuracy. Your body will be scanned in fine, three-dimensional detail. Thousands of compounds in your blood will be measured. Even the microbes that live inside you will be surveyed. You will get a custom-made iPad app to navigate data about yourself. Also, your wallet will be at least $25,000 lighter.

Venter, who came to the world’s attention in the 1990s when he led a campaign to produce the first draft of a human genome, launched Health Nucleus last month as part of his new company, Human Longevity. He has made clear that his aim is just as lofty as it was when he and his team sequenced the human genome or built a flu vaccine from a genetic sequence delivered to them over the Internet.

“We’re trying to show the value of actual scientific data that can change people’s lives,” Venter told STAT in some of his most extensive remarks yet about the project. “Our goal is to interpret everything in the genome that we can.”

Still, the initiative is drawing deep suspicion among some doctors who question whether Venter’s existing tests can tell patients anything meaningful at all. In interviews, they said they see Health Nucleus as the latest venture that could lead consumers to believe that more testing means improved health. That notion, they say, could drive customers to get procedures they don’t need, which might even be harmful.

“I think there is absolutely no evidence that any of those tests have any benefit for healthy people,” Dr. Rita Redberg, a cardiologist at the University of California at San Diego and the editor-in-chief of JAMA Internal Medicine, said when asked about Venter’s new project.

Venter has a black belt in media savvy — he can make the details of molecular biology alluring for viewers of 60 Minutes and TED talks alike — but off screen he has earned a reputation even from his critics for serious scientific achievements. His non-profit J. Craig Venter Institute, which he founded in 1992, now has a staff of 300. Scientists at the institute have explored everything from the ocean’s biodiversity to the Ebola virus.

Last year, at age 67, Venter cofounded Human Longevity, a company based in San Diego with branches in Mountain View, Calif., and Singapore that is building the largest human genome-sequencing operation on Earth, equipped with massive computing resources to analyze the data being generated. The firm’s database now contains highly accurate genome sequences from 20,000 people; another 3,000 genomes are being added each month.

Franz Och, the former head of Google Translate and an expert on machine learning, is leading a team that’s teaching computers to recognize patterns in the company’s databases that scientists themselves may not be able to see. To demonstrate the power of this approach, Human Longevity researchers are using machine learning to discover how genetic variations shape the human face.

“We can determine a good resemblance of your photograph straight from your genetic code,” said Venter.

Venter and his colleagues will be publishing the results of that study soon — most likely generating another round of headlines. But headlines don’t pay the bills, and at a company that’s got $70 million in funding from private investors, bills matter. The company is now exploring a number of avenues for generating income from its database. It has partnered with Discovery, an insurance company in England and South Africa, to read the DNA of their clients. For $250 apiece, it will sequence the protein-coding regions of the genome, known as exomes, and offer an interpretation of the data.

Health Nucleus could become yet another source of income for Human Longevity. The San Diego facility can handle eight to 12 people a day. There are plans to open more sites both in the United States and abroad. “You can do the math,” Venter said.

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Saudi Human Genome Program, International Barcode of Life Project

Reporter: Aviva Lev-Ari, PhD, RN

Life Tech Becomes Partner in Saudi Human Genome Program, International Barcode of Life Project

December 09, 2013

NEW YORK, GenomeWeb − Life Technologies has become a partner in two research projects, the Saudi Human Genome Program and the International Barcode of Life (iBOL) project, the company said this week. The projects will employ the firm’s Ion Proton, capillary electrophoresis, and PGM sequencing technologies.

The goal of the Saudi Human Genome Project, led by Saudi Arabia’s national funding agency, the King Abdulaziz City for Science and Technology (KACST), is to study the genetic basis of disease in Saudi Arabia and the Middle East.

Over the next five years, the project aims to sequence 100,000 genomes from individuals from the region using Life Tech’s Ion Proton technology. Sequencing will be initially conducted at 10 genome centers across Saudi Arabia, with five additional centers to be created in the future.

Life Tech will design and equip the centers, and provide “end-to-end solutions” and services for operations and informatics. Integrated Gulf Biosystems, Life Tech’s distributor in the Middle East, said it played a “pivotal role” in bringing Life Tech’s technology to KACST.

Results from the project will be used to build a Saudi-specific database, providing the basis for future personalized medicine in the Kingdom. Specifically, the information is expected to help with premarital and prenatal screening for rare genetic diseases, as well as for population studies.




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Curator: Aviva Lev-Ari, PhD, RN

In their discussion, the researchers argue that the U.S. Supreme Court now has a chance to shape the balance between the medical good versus inventor protection, adding that, in their opinion, the court should limit the patenting of existing nucleotide sequences, due to their broad scope and non-specificity in the human genome.

“I am extremely pro-patent, but I simply believe that people should not be able to patent a product of nature,” Dr. Mason says. “Moreover, I believe that individuals have an innate right to their own genome, or to allow their doctor to look at that genome, just like the lungs or kidneys. Failure to resolve these ambiguities perpetuates a direct threat to genomic liberty, or the right to one’s own DNA.”


Supreme Court May Decide Whether We Own Our Genes

March 26, 2013
Image Credit: Photos.com

Brett Smith for redOrbit.com – Your Universe Online

They may be responsible for everything in your life, from conception to death, they may be inside every living cell in your body – but you do not own your own genes, legally speaking.

According to a report in Genome Medicine, patents essentially cover the entire human genome, hampering research and raising the question of “genomic liberty.”

The legal standing of genomic patents could change next month when the Supreme Court reviews patent rights for two key breast and ovarian cancer genes, BRCA1 and BRCA2, which include segments of genetic code as small as 15 nucleotides, known as 15mers.

“This is, so to speak, patently ridiculous,” said report co-author Dr. Christopher E. Mason of Weill Cornell Medical College. “If patent claims that use these small DNA sequences are upheld, it could potentially create a situation where a piece of every gene in the human genome is patented by a phalanx of competing patents.”

In their report, Mason and Dr. Jeffrey Rosenfeld, an assistant professor of medicine at the University of Medicine & Dentistry of New Jersey, looked at patents for two different categories of DNA fragments:

  • long and
  • short.

They revealed 41 percent of the human genome is covered by “long” DNA patents that can include whole genes. Because many genes share similar sequences within their code that are patented, the combination of all these “short” DNA patents covers 100 percent of the genome.

“This demonstrates that short patent sequences are extremely non-specific and that a 15mer claim from one gene will always cross-match and patent a portion of another gene as well,” Mason said. “This means it is actually impossible to have a 15mer patent for just one gene.”

To reach their conclusions, the researchers first looked at small sequences within BRCA1 and noticed one of the company’s BRCA1 patents also covered almost 690 other human genes. Some of these genes are unrelated to breast cancer – instead being associated with brain development and heart functioning.

Next, researchers determined how many known genes are covered by 15mers in current patent claims. They found 58 patents covered at least ten percent of all bases of all human genes. The broadest patent claim matched 91.5 percent of human genes. When the team took patented 15mers and matched them to known genes, they found 100 percent of known genes are patented.

Finally, the team also looked at “long” DNA sequences from existing gene patents, ranging from a few dozen to thousands of base pairs. They found these long sequences added up to 41 percent of known human genes.

“There is a real controversy regarding gene ownership due to the overlap of many competing patent claims. It is unclear who really owns the rights to any gene,” Rosenfeld said. “While the Supreme Court is hearing one case concerning just the BRCA1 patent, there are also many other patents whose claims would cover those same genes.

“Do we need to go through every gene to look at who made the first claim to that gene, even if only one small part? If we resort to this rule, then the first patents to be granted for any DNA will have a vast claim over portions of the human genome,” he added.

Another legal question surrounds patented DNA sequences that cross species boundaries. The researchers found one company has the rights to 84 percent of all human genes for a patent they received for cow breeding.

Source: Brett Smith for redOrbit.com – Your Universe Online

Topics: Health Medical PharmaGeneticsGene patentBiologyGeneLiving modified organismAssociation for Molecular Pathology v. U.S. Patent and Trademark OfficeBRCA1DNASupreme CourtHuman genome


Human Genome: Name Your Price

Posted March 27, 2013 – 12:51 by a staff writer

Weill Cornell Medical College researchers have issued a warning that, according to the patent system, the vast majority of humans on the planet don’t ‘own’ their own genes, and in fact their biological make-up is being exploited for profit. Even seemingly innocent research into cow breeding can cover human genetic make-up.

As spotted by a Slashdot user, two researchers combing through patents on human DNA discovered that over 40,000 patents on DNA molecules have effectively declared the human genome for profit. A report in medical journal Genome Medicine said that humans may be losing their grip on “individual genomic liberty”.

Looking at two kinds of patented DNA sequences, or long and short fragments, 41 percent of the human genome is covered by DNA patents that can cover entire genes. According to the research, if all of the short sequence patents were allowed in aggregate they could cover 100 percent of the human genome.

Lead author Dr Christopher E Mason and co-author Dr Jeffrey Rosenfeld warned that short sequences from patents cover “virtually the entire genome, even outside of genes”. A Weill Cornell assistant professor asked: “How is it possible that my doctor cannot look at my DNA without being concerned about patent infringement?”

There will be a Supreme Court hearing about genomic patent rights next month that will debate the morality of a molecular diagnostic company claiming patents on key cancer genes, as well as on any small sequence of code within the BRCA1 gene. Cornell explained that at present, genes are able to be patented by researchers working in companies and institutions who discover genes that have potentially useful applications, like in testing for cancer risks. Because the patents can be held by companies or organisations, it is possible for the patent owner to charge doctors thousands of dollars for each diagnostic test.

The authors pointed out that in their studies, while engaged in research, it is common to come across a gene that’s patented “almost every day”. Their paper promises to examine how genes may have been impacted by held patents, and the extent of intellectual property on the genome. Gene patents can also relate between different species – for example, a company may have a patent for breeding cows that also covers a large percentage of human genes. They cited one company that owns 84 percent of all human genes because of a patent for cow breeding.

“There is a real controversy regarding gene ownership due to the overlap of many competing patent claims. It is unclear who really owns the rights to any gene,” Dr Rosenfeld said. “Do we need to go through every gene to look at who made the first claim to that gene, even if only one small part? If we resort to this rule, then the first patents to be granted for any DNA will have a vast claim over portions of the human genome.”

Lead author Dr Mason insisted he is pro-patent, but believes people “should not be able to patent a product of nature”.

“I believe that individals have an innate right to their own genome,” he said.


Other related articles on Genomics and Ethics on this Open Access Online Scientific Journal include the following:

Aviva Lev-Ari, PhD, RN

20.2 Understanding the Role of Personalized Medicine

Larry H Bernstein, MD, FACP

20.3 Attitudes of Patients about Personalized Medicine

Larry H Bernstein, MD, FACP

20.4  Genome Sequencing of the Healthy

Larry H. Bernstein, MD, FACP and Aviva Lev-Ari, PhD, RN

20.5   Genomics in Medicine – Tomorrow’s Promise

Larry H. Bernstein, MD, FACP

20.6  The Promise of Personalized Medicine

Larry H. Bernstein, MD, FACP

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Curators: Aviva Lev-Ari, PhD, RN and Larry Bernstein, MD, FACP

The essence of the message is summarized by Larry Bernstein, MD, FACP, as follows:

[1] we employ a massively parallel reporter assay (MPRA) to measure the transcriptional levels induced by 145bp DNA segments centered on evolutionarily-conserved regulatory motif instances and found in enhancer chromatin states
[2] We find statistically robust evidence that (1) scrambling, removing, or disrupting the predicted activator motifs abolishes enhancer function, while silent or motif-improving changes maintain enhancer activity; (2) evolutionary conservation, nucleosome exclusion, binding of other factors, and strength of the motif match are all associated with wild-type enhancer activity; (3) scrambling repressor motifs leads to aberrant reporter expression in cell lines where the enhancers are usually not active.
[3] Our results suggest a general strategy for deciphering cis-regulatory elements by systematic large-scale experimental manipulation, and provide quantitative enhancer activity measurements across thousands of constructs that can be mined to generate and test predictive models of gene expression.

Manolis Kellis and co-authors from the Massachusetts Institute of Technology and the Broad Institute describe a massively parallel reporter assay that they used to systematically study regulatory motifs falling within thousands of predicted enhancer sequences in the human genome. Using this assay, they examined 2,104 potential enhancers in two human cell lines, along with another 3,314 engineered enhancer variants. “Our results suggest a general strategy for deciphering cis-regulatory elements by systematic large-scale experimental manipulation,” they write, “and provide quantitative enhancer activity measurements across thousands of constructs that can be mined to generate and test predictive models of gene expression.”



Systematic dissection of regulatory motifs in 2,000 predicted human enhancers using a massively parallel reporter assay

  1. Pouya Kheradpour1,
  2. Jason Ernst1,
  3. Alexandre Melnikov2,
  4. Peter Rogov2,
  5. Li Wang2,
  6. Xiaolan Zhang2,
  7. Jessica Alston2,
  8. Tarjei S Mikkelsen2 and
  9. Manolis Kellis1,3

+Author Affiliations

  1. 1 MIT;

  2. 2 Broad Institute
  1. * Corresponding author; email: manoli@mit.edu


Genome-wide chromatin maps have permitted the systematic mapping of putative regulatory elements across multiple human cell types, revealing tens of thousands of candidate distal enhancer regions. However, until recently, their experimental dissection by directed regulatory motif disruption has remained unfeasible at the genome scale, due to the technological lag in large-scale DNA synthesis. Here, we employ a massively parallel reporter assay (MPRA) to measure the transcriptional levels induced by 145bp DNA segments centered on evolutionarily-conserved regulatory motif instances and found in enhancer chromatin states. We select five predicted activators (HNF1, HNF4, FOXA, GATA, NFE2L2) and two predicted repressors (GFI1, ZFP161) and measure reporter expression in erythroleukemia (K562) and liver carcinoma (HepG2) cell lines. We test 2,104 wild-type sequences and an additional 3,314 engineered enhancer variants containing targeted motif disruptions, each using 10 barcode tags in two cell lines and 2 replicates. The resulting data strongly confirm the enhancer activity and cell type specificity of enhancer chromatin states, the ability of 145bp segments to recapitulate both, the necessary role of regulatory motifs in enhancer function, and the complementary roles of activator and repressor motifs. We find statistically robust evidence that (1) scrambling, removing, or disrupting the predicted activator motifs abolishes enhancer function, while silent or motif-improving changes maintain enhancer activity; (2) evolutionary conservation, nucleosome exclusion, binding of other factors, and strength of the motif match are all associated with wild-type enhancer activity; (3) scrambling repressor motifs leads to aberrant reporter expression in cell lines where the enhancers are usually not active. Our results suggest a general strategy for deciphering cis-regulatory elements by systematic large-scale experimental manipulation, and provide quantitative enhancer activity measurements across thousands of constructs that can be mined to generate and test predictive models of gene expression.

  • Received June 26, 2012.
  • Accepted March 14, 2013.

This manuscript is Open Access.

This article is distributed exclusively by Cold Spring Harbor Laboratory Press for the first six months after the full-issue publication date (see http://genome.cshlp.org/site/misc/terms.xhtml). After six months, it is available under a Creative Commons License (Attribution-NonCommercial 3.0 Unported License), as described at http://creativecommons.org/licenses/by-nc/3.0/.



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Gene Sequencing – to the Bedside

Reporter: Larry H Bernstein, MD, FCAP

Gene sequencing leaves the laboratory

Maturing technology speeds medical diagnoses.
Erika Check Hayden  19 February 2013
The steep fall in the cost of sequencing a genome has, for the moment, slowed. Yet researchers attending this year’s Advances in Genome Biology and Technology (AGBT) meeting in Marco Island, Florida, on 20–23 February are not complaining. At a cost as low as US$5,000–10,000 per human genome, sequencing has become cheap and reliable enough that researchers are not waiting for the next sequencing machine to perfect new applications in medicine.
Single-cell genomics is allowing fertility clinics to screen embryos for abnormalities more cheaply.

Human genome to genes

Human genome to genes (Photo credit: Wikipedia)

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CRACKING THE CODE OF HUMAN LIFE: Milestones along the Way – Part IIA

Curator: Larry H Bernstein, MD, FCAP


Introduction and purpose

This material goes beyond the Initiation Phase of Molecular Biology, Part I.

Part II reviews the Human Genome Project and the decade beyond.

In a three part series:
Part IIA.  CRACKING THE CODE OF HUMAN LIFE: Milestones along the Way
Part IIB.  CRACKING THE CODE OF HUMAN LIFE: The Birth of BioInformatics & Computational Genomics
Part IIC.  CRACKING THE CODE OF HUMAN LIFE: Recent Advances in Genomic Analysis and Disease

Part III will conclude with Ubiquitin, it’s Role in Signaling and Regulatory Control.
Part I reviewed the huge expansion of the biological research enterprise after the Second World War. It concentrated on the

  • discovery of cellular structures,
  • metabolic function, and
  • creation of a new science of Molecular Biology.

Part II follows the race to delineation of the Human Genome, discovery methods and fundamental genomic patterns that are ancient in both animal and plant speciation. But it explores both the complexity and the systems view of the architecture that underlies and understanding of the genome.

These articles review a web-like connectivity between inter-connected scientific discoveries, as significant findings have led to novel hypotheses and many expectations over the last 75 years. This largely post WWII revolution has driven our understanding of biological and medical processes at an exponential pace owing to successive discoveries of

  • chemical structure,
  • the basic building blocks of DNA  and proteins,
  • nucleotide and protein-protein interactions,
  • protein folding, allostericity,
  • genomic structure,
  • DNA replication,
  • nuclear polyribosome interaction, and
  • metabolic control.

In addition, the emergence of methods for

  • copying,
  • removal,
  • insertion,
  • improvements in structural analysis
  • developments in applied mathematics that have transformed the research framework.

Part IIA:


Milestones along the Way

A NOVA interview with Francis Collins (NHGRI) (FC), J. Craig Venter (CELERA)(JCV), and Eric Lander (EL).
RK: For the past ten years, scientists all over the world have been painstakingly trying to read the tiny instructions buried inside our DNA. And now, finally, the “Human Genome” has been decoded.
EL: The genome is a storybook that’s been edited for a couple billion years.
The following will address the odd similarity of genes between man and yeast

EL: In the nucleus of your cell the DNA molecule resides that is about 10 angstroms wide curled up, but the amount of curling is limited by the negative charges that repel one another, but there are folds upon folds. If the DNA is stretched the length of the DNA would be thousands of feet.
EL: We have known for 2000 years that your kids look a lot like you. Well it’s because you must pass them instructions that give them the eyes, the hair color, and the nose shape they have. RK: Cracking the code of those minuscule differences in DNA that influence health and illness is what the Human Genome Project is all about. Since 1990, scientists all over the world have been involved in the effort to read all three billion As, Ts, Gs, and Cs of human DNA.  It took 10 years to find the one genetic mistake that causes cystic fibrosis. Another 10 years to find the gene for Huntington’s disease. Fifteen years to find one of the genes that increase the risk for breast cancer. One letter at a time, painfully slowly…     And then came the revolution. In the last ten years the entire process has been computerized. The computations can do a thousand every second and that has made all the difference. EL: This is basically a parts list with a lot of parts. If you take an airplane, a Boeing 777, I think it has like 100,000 parts. If I gave you a parts list for the Boeing 777 in one sense you’d know 100,000 components, screws and wires and rudders and things like that.  But you wouldn’t know how to put it together, or why it flies. We now have a parts list, and that’s not enough to understand why it flies.

The Human Genome

The Human Genome (Photo credit: dullhunk)

A Quest For Clarity

Tracy Vence is a senior editor of Genome Technology
Tracy Vence @GenomeTechMag
Projects supported by the US National Institutes of Health will have produced 68,000 total human genomes — around 18,000 of those whole human genomes — through the end of this year, National Human Genome Research Institute estimates indicate. And in his book, The Creative Destruction of Medicine, the Scripps Research Institute’s Eric Topol projects that 1 million human genomes will have been sequenced by 2013 and 5 million by 2014.
Daniel MacArthur, a group leader in Massachusetts General Hospital’s Analytic and Translational Genetics Unit estimates that “From a capacity perspective … millions of genomes are not that far off. If you look at the rate that we’re scaling, we can certainly achieve that.”    The prospect of so many genomes has brought clinical interpretation into focus. But there is an important distinction to be made between the interpretation of an apparently healthy person’s genome and that of an individual who is already affected by a disease.
In an April Science Translational Medicine paper, Johns Hopkins University School of Medicine‘s Nicholas Roberts and his colleagues reported that personal genome sequences for healthy monozygotic twin pairs are not predictive of significant risk for 24 different diseases in those individuals. The researchers concluded that whole-genome sequencing was not likely to be clinically useful. Ambiguities have clouded even the most targeted interpretation efforts.

  • Technological challenges,
  • meager sample sizes,
  • a need for increased,
  • fail-safe automation and most important
  • a lack of community-wide standards for the task.

have hampered researchers’ attempts to reliably interpret the clinical significance of genomic variation.

How signals from the cell surface affect transcription of genes in the nucleus.

James Darnell, Jr., MD, Astor Professor, Rockefeller
After graduation from Washington University School of Medicine he worked with Francois Jacob at the Pasteur Institute in Paris and served as Vice President for Academic Affairs at Rockefeller in 1990-91. He is the coauthor with S.E. Luria of General Virology and the founding author with Harvey Lodish and David Baltimore of Molecular Cell Biology, now in its sixth edition. His book RNA, Life’s Indispensable Molecule was published in July 2011 by Cold Spring Harbor Laboratory Press. A member of the National Academy of Sciences since 1973, recipient of  numerous awards, including the 2003 National Medal of Science, the 2002 Albert Lasker Award.
Using interferon as a model cytokine, the Darnell group discovered that cell transcription was quickly changed by binding of cytokines to the cell surface. The bound interferon led to the tyrosine phosphorylation of latent cytoplasmic proteins now called STATs (signal transducers and activators of transcription) that dimerize by

  • reciprocal phosphotyrosine-SH2 interchange.
  • accumulate in the nucleus,
  • bind DNA and drive transcription.

This pathway has proved to be of wide importance with seven STATs now known in mammals that take part in a wide variety of developmental and homeostatic events in all multicellular animals. Crystallographic analysis defined functional domains in the STATs, and current attention is focused on two areas:

  • how the STATs complete their cycle of  activation and inactivation, which requires regulated tyrosine dephosphorylation; and how
  • persistent activation of STAT3 that occurs in a high proportion of many human cancers contributes to blocking apoptosis in cancer cells.

Current efforts are devoted to inhibiting STAT3 with modified peptides that can enter cells.

Cell cycle regulation and the cellular response to genotoxic stress

Stephen J Elledge, PhD, Gregor Mendel Professor of Genetics and Medicine, Investigator, Howard Hughes Medical Institute, Harvard Medical School
As a postdoctoral fellow at Stanford working on eukaryotic homologous recombination, he serendipitously found a family of genes known as ribonucleotide reductases. He subsequently showed that

  • these genes are activated by DNA damage and
  • could serve as tools to help scientists dissect the signaling pathways
  • through which cells sense and respond to DNA damage and replication stress.

At Baylor College of Medicine he made a second major breakthrough with the discovery of the cyclin-dependent kinase 2 gene (Cdk2), which

  • controls the G1-to-S cell cycle transition,
  • an entry checkpoint for the cell proliferation cycle and
  • a critical regulatory step in tumorigenesis.

From there, using a novel “two-hybrid” cloning method he developed, Elledge and Wade Harper, PhD, proceeded to

  • isolate several members of the Cdk2-inhibitory family.

Their discoveries included the p21 and p57 genes, mutations in the latter (responsible for Beckwith-Wiedemann syndrome), characterized by somatic overgrowth and increased cancer risk. Elledge is also recognized for his work in understanding

  • proteome remodeling through ubiquitin-mediated proteolysis.
  • they identified F-box proteins that regulate protein degradation in the cell by
  1. binding to specific target protein sequences and then
  2. marking them with ubiquitin for destruction by the cell’s proteasome machinery.

This breakthrough resulted in

  • the elucidation of the cullin ubiquitin ligase family,
  • which controls regulated protein stability in eukaryotes.

nature10774-f5.2  nature10774-f3.2   ubiquitin structures  Rn1  Rn2

Elledge’s recent research has focused on the cellular mechanisms underlying DNA damage detection and cancer using genetic technologies. In collaboration with Cold Spring Harbor Laboratory researcher Gregory Hannon, PhD, Elledge has generated complete human and mouse short hairpin RNA (shRNA) libraries for genome-wide loss-of-function studies. Their efforts have led to

  • the identification of a number of tumor suppressor proteins
  • genes upon which cancer cells uniquely depend for survival.

This work led to the development of the “non-oncogene addiction” concept. This is noted as follows:

  • proteome remodeling through ubiquitin-mediated proteolysis
  • F-box proteins regulate protein degradation in the cell by binding to specific target protein sequences
  • and then marking them with ubiquitin for destruction by the cell’s proteasome machinery
  • elucidation of the cullin ubiquitin ligase family, which controls regulated protein stability in eukaryotes

Playing the dual roles of inventor and investigator, Elledge developed original techniques to define

  • what drives the cell cycle and
  • how cells respond to DNA damage.

By using these tools, he and his colleagues have identified multiple genes involved in cell-cycle regulation.

Elledge’s work has earned him many awards, including a 2001 Paul Marks Prize for Cancer Research and a 2003 election to the National Academy of Sciences. In his Inaugural Article (1), published in this issue of PNAS, Elledge and his colleagues describe the function of Fbw7, a protein involved in controlling cell proliferation (see below). Elledge studied the error-prone DNA repair mechanism in E-Coli (Escherichia coli) called SOS mutagenesis for his PhD thesis at MIT. His work identified  and described

  • the regulation of a group of enzymes now known as error-prone polymerases,
  • the first members of which were the umuCD genes in E. coli.

It was then that he developed a new cloning tool. Elledge invented a technique that allowed him to approach future cloning problems of this type with great rapidity. With the new technique, “you could make large libraries in lambda that behave like plasmids. We called them `phasmid’ vectors, like plasmid and phage together”. The phasmid cloning method was an early cornerstone for molecular biology research.

Elledge began working on homologous recombination in postdoctoral fellowship at Stanford University, an important niche in the field of eukaryotic genetics. Working with the yeast genome, Elledge searched for rec A, a gene that allows DNA to recombine homologously. Although he never located rec A, he discovered a family of genes known as ribonucleotide reductases (RNRs), which are involved in DNA production. Rec A and RNRs share the same last 4 amino acids, which caused an antibody crossreaction in one of Elledge’s experiments. Initially disappointed with the false positives in his hunt for rec A, Elledge was later delighted with his luck. He found that

  • RNRs are turned  on by DNA damage, and
  • these genes are regulated by the cell cycle.

Prior to leaving Stanford, Elledge attended a talk at the University of California, San Francisco, by Paul Nurse, a leader in cell-cycle research who would later win the 2001 Nobel Prize in medicine. Nurse described his success in isolating the homolog of a key human cell-cycle kinase gene, Cdc2, by using a mutant strain of yeast (8). Although Nurse’s methods were primitive, Elledge was struck by the message he carried: that

  • cell-cycle regulation was functionally conserved, and
  • many human genes could be isolated by looking for complimentary genes in yeast.

Elledge then took advantage of his past successes in building phasmid vectors to build a versatile human cDNA library that could be expressed in yeast. After setting up a laboratory at Baylor, he introduced this library into yeast, screening for complimentary cell-cycle genes.  He quickly identified the same Cdc2 gene isolated by Nurse. However, Elledge also discovered a related gene known as Cdk2. Elledge subsequently found that

  • Cdk2 controlled the G1 to S cell-cycle transition, a step that often goes awry in cancer. These results were published in the EMBO Journal in 1991.

He then continued to use

  • RNRs to perform genetic screens to
  • identify genes involved in sensing and responding to DNA damage.

He subsequently worked out the

  • signal transduction pathways in both yeast and humans that recognize damaged DNA and replication problems.

These “checkpoint” pathways are central to the

  • prevention of genomic instability and a key to understanding tumorigenesis.

This contribution is part of the special series of Inaugural Articles by members of the National Academy of Sciences elected on April 29, 2003.

Defective cardiovascular development and elevated cyclin E and Notch proteins in mice lacking the Fbw7 F-box protein.

Tetzlaff MT, Yu W, Li M, Zhang P, Finegold M, Mahon K , Harper JW, Schwartz RJ, and SJ Elledge. PNAS 2004; 101(10): 3338-3345. cgi doi 10.1073.  pnas.0307875101

The mammalian F-box protein Fbw7 and its Caenorhabditis elegans counterpart Sel-10 have been implicated in

  • the ubiquitin-mediated turnover of cyclin E
  • as well as the Notch Lin-12 family of transcriptional activators. Both unregulated
  1. Notch and cyclin E
  2. promote tumorigenesis, and
  3. inactivate mutations in human

Fbw7 studies suggest that it may be a tumor suppressor. To generate an in vivo system to assess the consequences of such unregulated signaling, we generated mice deficient for Fbw7.  Fbw7-null mice die around 10.5 days post coitus because of a combination of deficiencies in hematopoietic and vascular development and heart chamber mutations. The absence of Fbw7 results in elevated levels of cyclin E, concurrent with inappropriate DNA replication in placental giant trophoblast cells. Moreover, the levels of both Notch 1 and Notch 4 intracellular domains were elevated, leading to stimulation of downstream transcriptional pathways involving Hes1, Herp1, and Herp2. These data suggest essential functions for Fbw7 in controlling cyclin E and Notch signaling pathways in the mouse.

Science as an Adventure


Prof. Avram Hershko – Science as an Adventure
Prof. Avram Hershko shared the 2004 Nobel Prize in Chemistry with Aaron Ciechanover and Irwin Rose for “for the discovery of ubiquitin-mediated protein degradation.”


Gene Switches

Nipam Patel is a professor in the Departments of Molecular and Cell Biology and Integrative Biology at UC Berkeley and runs a research laboratory that studies the role, during embryonic development, of homeotic genes (the genetic switches described in this feature). “Ghost in Your Genes” focuses on epigenetic “switches” that turn genes “on” or “off.” But not all switches are epigenetic; some are genetic. That is, other genes within the chromosome turn genes on or off. In an animal’s embryonic stage, these gene switches play a predominant role in laying out the animal’s basic body plan and perform other early functions;

  • the epigenome begins to take over during the later stages of embryogenesis.

Beginning as a fertilized single egg that egg becomes many different kinds of cells.  Altogether, multicellular organisms like humans have thousands of differentiated cells. Each is optimized for use in the brain, the liver, the skin, and so on. Remarkably, the DNA inside all these cells is exactly the same. What makes the cells differ from one another is that different genes in that DNA are either turned on or off in each type of cell.

Take a typical cell, such as a red blood cell. Each gene within that cell has a coding region that encodes the information used to make a particular protein. (Hemoglobin shuttles oxygen to the tissues and carbon dioxide back out to the lungs—or gills, if you’re a fish.) But another region of the gene, called “regulatory DNA,” determines whether and when the gene will be expressed, or turned on, in a particular kind of cell. This precise transcribing of genes is handled by proteins known as transcription factors, which bind to the regulatory DNA, thereby generating instructions for the coding region.

One important class of transcription factors is encoded by the so called homeotic, or Hox, genes. Found in all animals, Hox genes act to “regionalize” the body along the embryo’s anterior-to-posterior (head-to-tail) axis. In a fruit fly, for example, Hox genes lay out the various main body segments—the head, thorax, and abdomen. Amazingly, all animals, from fruit flies to mice to people, rely on the same basic Hox-gene complex. Using different-colored antibody stains, we can see exactly where and to what degree Hox genes are expressed. Each Hox gene is expressed in a specific region along the anterior-to-posterior axis of the embryo.

A fly’s body has three main divisions: head, thorax, and abdomen. We’ll focus on the thorax, which itself has three main segments. In a normal adult fly, the second thoracic segment features a pair of wings, while the third thoracic segment has a pair of small, balloon-shaped structures called halteres. A modified second wing, the haltere serves as a flight stabilizer. In order for the pair of wings and the pair of halteres (as well as all other parts of the fly) to develop properly, the fly’s suite of

  • Hox genes must be expressed in a precise way and at precise times.

During development, the fly’s two wings grow from a structure in the larva known as the wing imaginal disk. (An imago is an insect in its final, adult state.) The haltere grows from the larval haltere imaginal disk. Remember the Ubx Hox gene? Using staining again, we can detect the gene product of Ubx. This reveals that

  • the Ubx gene is naturally “off” in the wing disk—
  • and is “on” in the haltere disk.
  • Now you’ll see what happens when the Ubx gene—just one of a large number of Hox genes—is turned off in the haltere disk. What if a genetic mutation caused the Ubx gene to be turned off, during the larval stage, in the third thoracic segment, the segment that normally produces the haltere? Instead of a pair of halteres, the fly has a second set of wings. With the switch of that single Hox gene, Ubx, from on to off, the third thoracic segment becomes an additional second thoracic segment and the pair of halteres became a second pair of wings. This illustrates the remarkable ability of transcription factors like Ubx to control patterning as well as cell type during development.


A. Data Suggests “Gene” Redefinition

As part of a huge collaborative effort called ENCODE (Encyclopedia of DNA Elements), a research team led by Cold Spring Harbor Laboratory (CSHL) Professor Thomas Gingeras, PhD, publishes a genome-wide analysis of RNA messages, called transcripts, produced within human cells.
Their analysis—one component of a massive release of research results by ENCODE teams from 32 institutes in 5 countries, with 30 papers appearing in 3 different high-level scientific journals—shows that three-quarters of the genome is capable of being transcribed.  This indicates that nearly all of our genome is dynamic and active.  It stands in marked contrast to consensus views prior to ENCODE’s comprehensive research efforts, which suggested that

  • only the small protein-encoding fraction of the genome was transcribed.

The vast amount of data generated with advanced technologies by Gingeras’ group and others in the ENCODE project changes the prevailing understanding of what defines a gene. The current outstanding question concerns

  • the nature and range of those functions.  It is thought that these
  • “non-coding” RNA transcripts act something like components of a giant, complex switchboard, controlling a network of  many events in the cell by
  1. regulating the processes of
  2. replication,
  3. transcription
  4. and translation

– that is, the copying of DNA and the making of proteins is based on information carried by messenger RNAs.  With the understanding that so much of our DNA can be transcribed into RNA comes the realization that there is much less space between what we previously thought of as genes, Gingeras points out.

The full ENCODE Consortium data sets can be freely accessed through

  • the ENCODE project portal as well as at the University of California at Santa Cruz genome browser,
  • the National Center for Biotechnology Information, and
  • the European Bioinformatics Institute.

Topic threads that run through several different papers can be explored via the ENCODE microsite page at http://Nature.com/encode.    Date: September 5, 2012   Source: Cold Spring Harbor Laboratory

1000 Genomes Project Team Reports on Variation Patterns

(from Phase I Data) October 31, 2012 GenomeWeb

In a study appearing online today in Nature, members of the 1000 Genomes Project Consortium presented an integrated haplotype map representing the genomic variation present in more than 1,000 individuals from 14 human populations.  Using data on 1,092 individuals tested by

  • low-coverage whole-genome sequencing,
  • deep exome sequencing, and/or
  • dense genotyping,

the team looked at the nature and extent of the rare and common variation present in the genomes of individuals within these populations. In addition to population-specific differences in common variant profiles, for example, the researchers found distinct rare variant patterns within populations from different parts of the world — information that is expected to be important in interpreting future disease studies. They also encountered a surprising number of the variants that are expected to impact gene function, such as

  • non-synonymous changes,
  • loss-of-function variants, and, in some cases,
  • potentially damaging mutations.

ENCODE was designed to pick up where the Human Genome Project left off.
Although that massive effort revealed the blue­print of human biology, it quickly became clear that the instruction manual for reading the blueprint was sketchy at best. Researchers could identify in its 3 billion letters many of the regions that code for proteins, but they make up little more than 1% of the genome, contained in around 20,000 genes. ENCODE, which started in 2003, is a massive data-collection effort designed to catalogue the

  • ‘functional’ DNA sequences,
  • learn when and in which cells they are active and
  • trace their effects on how the genome is
  1. packaged,
  2. regulated and
  3. read.

After an initial pilot phase, ENCODE scientists started applying their methods to the entire genome in 2007. That phase came to a close with the publication of 30 papers, in Nature, Genome Research and Genome Biology. The consortium has assigned some sort of function to roughly 80% of the genome, including

  • more than 70,000 ‘promoter’ regions — the sites, just upstream of genes, where proteins bind to control gene expression —
  • and nearly 400,000 ‘enhancer’ regions that regulate expression of  distant genes (see page 57)1. But the job is far from done.

Junk DNA? What Junk DNA?

New data reveals that at least 80% of the human genome encodes elements that have some sort of biological function. [© Gernot Krautberger – Fotolia.com] Far from containing vast amounts of junk DNA between its protein-coding genes, at least 80% of the human genome encodes elements that have some sort of biological function, according to newly released data from the Encyclopedia of DNA Elements (Encode) project, a five-year initiative that aims to delineate all functional elements within human DNA. The massive international project, data from which are published in 30 different papers in Nature, Genome Research, Genome Biology, the Journal of Biological Chemistry, Science, and Cell, has identified four million gene switches, effectively

  • regulatory regions in the genome where
  • proteins interact with the DNA to control gene expression.

Overall, the Encode data define regulatory switches that are scattered all over the three billion nucleotides of the genome. In fact, the data suggests,

  • the regions that lie between gene-coding sequences contain a wealth of previously unrecognized functional elements,Including
  • nonprotein-coding RNA transcribed sequences,
  • transcription factor binding sites,
  • chromatin structural elements, and
  • DNA methylation sites.

The combined results suggest that 95% of the genome lies within 8 kb of a DNA-protein interaction, and 99% lies within 1.7 kb of at least one of the biochemical events, the researchers say. Importantly, given the complex three-dimensional nature of DNA, it’s also apparent that

  • a regulatory element for one gene may be located quite some ‘linear’ distance from the gene itself.

“The information processing and the intelligence of the genome reside in the regulatory elements,” explains Jim Kent, director of the University of California, Santa Cruz Genome Browser project and head of the Encode Data Coordination Center. “With this project, we probably went from understanding less than 5% to now around 75% of them.”
The ENCODE results also identified SNPs within regulatory regions that are associated with a range of diseases, providing new insights into the roles that

  • noncoding DNA plays in disease development.

“As much as nine out of 10 times, disease-linked genetic variants are not in protein-coding regions,” comments Mike Pazin, Encode program director at the National Human Genome Research Institute.  “Far from being junk DNA, this regulatory DNA clearly makes important contributions to human disease.”

Other Related Articles on this Open Access Online Scientific Journal, include the following: 


Big Data in Genomic Medicine LHB


BRCA1 a tumour suppressor in breast and ovarian cancer – functions in transcription, ubiquitination and DNA repair S Saha

Computational Genomics Center: New Unification of Computational Technologies at Stanford A Lev-Ari

Personalized medicine gearing up to tackle cancer ritu saxena

Differentiation Therapy – Epigenetics Tackles Solid Tumors sj Williams

Mechanism involved in Breast Cancer Cell Growth: Function in Early Detection & Treatment A Lev-Ari

The Molecular pathology of Breast Cancer Progression tilde barliya`

Paradigm Shift in Human Genomics – Predictive Biomarkers and Personalized Medicine – Part 1 (pharmaceuticalintelligence.com) A Lev-Ari


LEADERS in Genome Sequencing of Genetic Mutations for Therapeutic Drug Selection in Cancer Personalized Treatment: Part 2 A Lev-Ari

Personalized Medicine: An Institute Profile – Coriell Institute for Medical Research: Part 3 A Lev-Ari

Harnessing Personalized Medicine for Cancer Management, Prospects of Prevention and Cure: Opinions of Cancer Scientific Leaders @ http://pharmaceuticalintelligence.com ALA
http://pharmaceuticalintelligence.com/2013/01/13/7000/Harnessing Personalized Medicine for Cancer Management, Prospects of Prevention and Cure: Opinions of Cancer Scientific Leaders/

GSK for Personalized Medicine using Cancer Drugs needs Alacris systems biology model to determine the in silico effect of the inhibitor in its “virtual clinical trial” A Lev-Ari

Recurrent somatic mutations in chromatin-remodeling and ubiquitin ligase complex genes in serous endometrial tumors S Saha

Personalized medicine-based cure for cancer might not be far away ritu saxena

Human Variome Project: encyclopedic catalog of sequence variants indexed to the human genome sequence A Lev-Ari

Prostate Cancer Cells: Histone Deacetylase Inhibitors Induce Epithelial-to-Mesenchymal Transition sjwilliams

Inspiration From Dr. Maureen Cronin’s Achievements in Applying Genomic Sequencing to Cancer Diagnostics A Lev-Ari

The “Cancer establishments” examined by James Watson, co-discoverer of DNA w/Crick, 4/1953 A Lev-Ari

Directions for genomics in personalized medicine lhb

How mobile elements in “Junk” DNA promote cancer. Part 1: Transposon-mediated tumorigenesis. SJwilliams

Mitochondria: More than just the “powerhouse of the cell” eritu saxena

Mitochondrial fission and fusion: potential therapeutic targets? Ritu saxena

Mitochondrial mutation analysis might be “1-step” away ritu saxena

mRNA interference with cancer expression lhb

Expanding the Genetic Alphabet and linking the genome to the metabolome LHB

Breast Cancer, drug resistance, and biopharmaceutical targets lhb

Breast Cancer: Genomic profiling to predict Survival: Combination of Histopathology and Gene Expression Analysis A Lev-Ari

Gastric Cancer: Whole-genome reconstruction and mutational signatures A Lev-Ari

Ubiquinin-Proteosome pathway, autophagy, the mitochondrion, proteolysis and cell apoptosis lhb

Genomic Analysis: FLUIDIGM Technology in the Life Science and Agricultural Biotechnology A Lev-Ari

Reveals from ENCODE project will invite high synergistic collaborations to discover specific targets A. Sarkar


ENCODE: the key to unlocking the secrets of complex genetic diseases R. Saxena


Impact of evolutionary selection on functional regions: The imprint of evolutionary selection on ENCODE regulatory elements is manifested between species and within human populations s Saha


ENCODE Findings as Consortium A Lev-Ari


Genomics Orientations for Personalized Medicine SJH, ALA, LHB


2013 Genomics: The Era Beyond the Sequencing of the Human Genome: Francis Collins, Craig Venter, Eric Lander, et al.


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2013 Genomics: The Era Beyond the Sequencing of the Human Genome: Francis Collins, Craig Venter, Eric Lander, et al.

Curator: Aviva Lev-Ari, PhD, RN


One decade following the completion of the  Sequencing of the Human Genome — the field of Genomics, the discipline that has emerged as a result of project completion has FOUR concentrations:



Sequencing Human Genome: the Contributions of Francis Collins and Craig Venter

By: Jill Adams, Ph.D. (Freelance science writer in Albany, NY) © 2008 Nature Education
Citation: Adams, J. (2008) Sequencing human genome: the contributions of Francis Collins and Craig Venter. Nature Education 1(1)
How did it become possible to sequence the 3 billion base pairs in the human genome? More than a quarter of a century’s worth of work from hundreds of scientists made such projects possible.

Before the middle of the twentieth century, the gene was an abstract concept thought to physically resemble a “bead on a string,” and within the scientific community, it was accepted that each gene was associated with a single protein, enzyme, or metabolic disorder. However, this began to change during the 1950s with the birth of modern molecular genetics. In 1952, Alfred Hershey and Martha Chase proved that DNA was themolecule of heredity, and shortly thereafter, Watson, Crick, Franklin, and Wilkins solved the three-dimensional structure ofDNA. By 1959, Jerome Lejeune had demonstrated that Down syndrome was linked to chromosomal abnormalities (Lejeune et al., 1959). Next, the 1961 discovery of mRNA (Jacob & Monod, 1964) and the 1966 cracking of the genetic code (Figure 1; Nirenberg et al., 1966) made it possible to predict proteinsequences based on DNA sequence alone. Nonetheless, although it was well established by this time that DNA was the heredity material and that each nucleus must contain the complete DNA required to instruct the chemical processes of anorganism, the details of reading individual gene sequences, let alone whole genomes, were out of the technical grasp of scientists.

A large part of the reason for this inability to read genesequences was the fact that there were simply very few sequences available to read; furthermore, the tools required to identify, isolate, and manipulate desired stretches of DNA were just evolving. Then, during the late 1960s and early 1970s, the combined work of several groups of researchers culminated in the isolation of proteins from prokaryotes using DNA cut at specific sites and spliced with DNA from other species(Meselson & Yuan, 1968; Jackson et al., 1972; Cohen et al., 1973). With these tools in place, the recombinant DNA age was about to allow scientists to start cloning genes en masse for the first time. Indeed, with the advent of Maxam-Gilbert DNAsequencing in the mid-1970s (Maxam & Gilbert, 1977), it actually became possible to read the entire sequence of a clonedgene, perhaps 1,000 to 30,000 base pairs long, with relative ease.


Collins and Other Researchers Master Gene Mapping


Thanks to these advances, mapping of important disease genes was all the rage by the 1980s, and Francis Collins was one of the masters of this process. Collins made a name for himself by discovering the location of three important disease genes—those responsible for cystic fibrosis, Duchenne muscular dystrophy, and Huntington’s disease. The accomplishments were a result of both cutting-edge cloning techniques like chromosome jumping (Collins et al., 1987; Richards et al., 1988) and plain perseverance. Collins wasn’t the only researcher actively “gene hunting” at this time, however; hundreds of other investigators were also racing to publish detailed descriptions of every new disease gene found.

During the 1980s, the importance of genes was obvious, but determining their location on chromosomes or their sequence of DNA nucleotides was laborious. Early studies of the genome were technically challenging and slow. Reagents were expensive, and the conditions for performing many reactions were temperamental. It therefore took several years to sequence single genes, and most genes were only partially cloned and described. Scientists had already reached the milestone of fully sequencing their first genome—that of the FX174 bacteriophage, whose 5,375 nucleotides had been determined in 1977 (Sanger et al., 1977b)—but this endeavor proved much easier than sequencing the genomes of more complex life forms. Indeed, the prospect of sequencing the 1 million base pairs of the E. coli genome or the 3 billion nucleotides of the humangenome seemed close to impossible. For example, an article published in the New York Times in 1987 noted that only 500 human genes had been sequenced (Kanigel, 1987). At the time, that was thought to be about 1% of the total, and given the pace of discovery, it was believed that complete sequencing of the human genome would take at least 100 years.

In addition to questions about the technical challenges and costs associated with sequencing large genomes, a number of concerns about the scientific basis of these endeavors were also raised. Why spend the time, money, and resources to sequence the whole genome when only a small percentage of it was actually genes? With the huge scale of these projects, there was a logic to prioritizing certain tasks over others—specifically, the target sequencing of coding sequences (genes). Thus, instead of sequencing the raw genome, many researchers sought to study cDNA collections; these are DNA strands that are generated by collecting mRNA from a tissue, then converting it back to complementary DNA. Because cDNA starts as a message in a cell, it represents an actively expressed gene. Moreover, because cells behave differently in different tissues and at different developmental stages, specialized cDNA libraries are valuable tools for assessing what specific genes are at work in a cell at any given time. Scientists could therefore use these libraries to prioritize their sequencing in order to focus on coding sequences first.

At the same time, researchers were also working to identify many more polymorphic genetic markers to use as tools in genemapping. Polymorphisms are the individual DNA base changes that make each of us unique at the level of DNA. The number of known human polymorphisms and microsatellite repeats increased to more than 2,000 by 1992—or 1 per every 2.5 million bases or so (Weissenbach et al., 1992). As researchers characterized more and more polymorphic markers, their chances ofmapping a gene of interest to its chromosomal location increased dramatically.


Venter Combines Approaches to Make Sequencing Faster and Less Expensive


Thus, by the late 1980s, multiple approaches for sequencingDNA were in use, but costs and time constraints were still a limiting factor to research. However, this all began to change with the work of National Institutes of Health (NIH) scientist J. Craig Venter. For several years, Venter had been using automated DNA sequencers to sequence portions of chromosomes associated with Huntington’s disease and myotonic dystrophy (Adams et al., 1991, 1992). Next, Venter tapped collections of cDNA molecules made from brain tissues. Then, in a 1991 paper, he described how he harnessed the power of his high-tech equipment to sequence more than 600 expressed sequence tags (ESTs) from a brain cDNA collection, identifying about half of them as genes, far more than anyone else had ever reported in a single paper to date. Not only did Venter’s paper make an impact, but so did his claims that in his laboratory alone, he could sequence as many as 10,000 ESTs a year at the low cost of $0.12/base. The next year, in a second paper, Venter published the sequences of more than 2,000 genes, although some were incomplete. This brought the total to 2,500 genes sequenced in one laboratory, which was as many as had been sequenced in the entire world to that point (Figure 2).

Many scientists spoke out in criticism of Venter’s brash approach. They noted that by sequencing ESTs, Venter was missing promoter sequences and other sites on DNA that were important for the regulation of gene expression. Furthermore, many critics argued that a focus on cheap volume was no substitute for careful, painstaking science. However, Venter’s speed also spurred other groups—namely, the NIH effort led by James Watson—to step up their efforts to finish the Human Genome Project sooner.

In 1992, Venter left the NIH and, with the help of a venture capitalist, started a nonprofit research institute at which he quickly set up 30 automated sequencers. Venter’s aim in doing so was to complete the sequencing of the human genomefaster than the government-backed (“public”) effort. This competition would later culminate in the simultaneous publication of the draft human genome sequence by both public and private efforts, ahead of schedule and below budget.

The events that occurred from the discovery of DNA’s structure and role as a heredity molecule up through Venter’s high-throughput EST experiments roughly delimit what is now known as the pregenomic era of molecular biology. The molecular tools and methods developed during this era were essential to reaching the milestone of sequencing the entire humangenome.


References and Recommended Reading

Adams, M. D., et al. Complementary DNA sequencing: “Expressed sequence tags” and the Human Genome Project. Science252, 1651–1656 (1991)

———. Sequence identification of 2,375 human brain genes. Nature 355, 632–634 (1992) doi:10.1038/355632a0 (link to article)

Cohen, S. N., et al. Construction of biologically functional bacterial plasmids in vitroProceedings of the National Academy of Sciences 70, 3240–3244 (1973)

Collins, F. S., et al. Construction of a general human chromosome jumping library, with application to cystic fibrosis. Science235, 1046–1049 (1987)

Dulbecco, R. A turning point in cancer research: Sequencing the human genome. Science 231, 1055–1056 (1986) doi:10.1126/science.3945817

Jackson, D. A., et al. Biochemical method for inserting new genetic information into DNA of simian virus 40: Circular SV40 DNA molecules containing lambda phage genes and the galactose operon of Escherichia coliProceedings of the National Academy of Sciences 69, 2904–2909 (1972)

Jacob, F., & Monod, J. Biochemical and genetic mechanisms of regulation in the bacterial cell. Bulletin de Societe Chimique de France 46, 1499–1532 (1964)

Kanigel, R. The genome project. New York Times, 13 December (1987)

Lejeune, J., et al. Mongolism: A chromosomal disease (trisomy). Bulletin de l’Academie Nationale de Medecine 143, 256–265 (1959)

Maxam, A., & Gilbert, W. A new method of sequencing DNA. Proceedings of the National Academy of Sciences 74, 560–564 (1977)

Meselson, M., & Yuan, R. DNA restriction enzyme from E. coliNature 217, 1110–1114 (1968)

Nirenberg, M. W., et al. The RNA code and protein synthesis. Cold Spring Harbor Symposia on Quantitative Biology 31, 11–24 (1966)

Richards, J. E., et al. Chromosome jumping from D4S10 (G8) toward the Huntington disease gene. Proceedings of the National Academy of Sciences 5, 6437–6441 (1988)

Sanger, F., et al. Nucleotide sequence of bacteriophage phi X174 DNA. Nature 265, 687–695 (1977a) (link to article)

Sanger, F., et al. DNA sequencing with chain-terminating inhibitors. Proceedings of the National Academy of Sciences 74, 5463–5467 (1977b)

Weissenbach, J., et al. A second-generation linkage map of the human genome. Nature 359, 794–801 (1992) doi:10.1038/359794a0 (link to article)

Davies, K. Cracking the Genome: Inside the Race to Unlock Human DNA (New York, Free Press, 2001)



Contributors to Genomics recognized by Dan David Prize Awards



Laureates 2012 – 2012 Future – Genome Research


Founding Director, Broad Institute Harvard and MIT and director of its Genome Biology Program, Cambridge, MA, USA

Prof. Eric Lander has been a major intellectual force in genomics research. Building on his background in mathematics, he placed genomics on a firm quantitative foundation.

With David Botstein and Phil Green he developed algorithms to allow effective use of polymorphism data for genetic mapping and published the first genetic linkage map of the human genome. As the human genome project got underway, he demonstrated an unusual ability to innovate in the organization of high-throughput methods first in creating genetic maps of the mouse and rat genomes and later as a major contributor to the Human Genome Project.

Lander was a powerful and respected voice in the planning and execution of the genome project. The Center he led contributed much of the data, he pioneered many of the analyses of genome sequence data, and he led in the writing of the landmark publication describing the Human Genome Project first as a draft sequence in Nature, 2001 and later as a full sequence in Nature, 2004. This has become the standard human reference sequence.

Lander has also been at the forefront of applying the genome sequence to the study of human disease, generating the first deep SNP catalogs, applying them to understand the haploid structure of the genome and more recently, championing the use of common variation to the study of complex traits. He has led efforts to understand the functional elements of the human genome, generating genome sequence from multiple other mammals to delineate the conserved elements and to define noncoding RNAs and characterize chromatin states.

Among Prof. Lander’s awards are:  Honorary Degree, Columbia University; Honorary Doctorate, Lund University, Sweden; Honorary Doctorate, University of Massachusetts at Lowell; Gairdner  Foundation International Award, Canada; Max Delbruck Medal, Berlin; Honorary Doctorate, Mount Sinai School of Medicine, New York; Honorary Doctorate, Tel Aviv Universtiy; Millennium Lecturer, The White House; Member of the American Academy of Arts and Sciences; Member of the American Academy of Achievement; and Member of the U.S. National Academy of Sciences.

Beyond his immediate scientific contributions, Eric Lander has attracted talented investigators to the field and fostered their careers. He has also served the community, most recently as co-Chair of the President’s Council of Advisors on Science and Technology.



Eric S. Lander, Ph.D.
By Karen Hopkin

In many ways, Eric Lander’s career has taken as many twists and turns as there are in the helical strands of DNA that he now spends his time trying to decode. Before turning his attention to the human genome, Lander worked as a mathematician, an economist, and even a newspaper reporter, amassing an impressive array of awards and achievements along the way. If the equation that describes Lander’s life story has a common denominator, it would have to be his pursuit of intellectual challenge.

It all began with math. From the start, he was captivated by the power and beauty of numbers. “Math is so elegant. Ideas dovetail perfectly with other ideas to form beautiful intellectual edifices,” he says. What’s more, these mathematical constructions can be used to describe and understand the world around us—making mathematics, to Lander’s mind, the purest product of human thought and “the highest form of crystallized abstraction.”

Lander was a master of mathematics. He placed second in a national math test and h ad the highest grades in his class at Stuyvesant High, one of New York City’s top schools for students who show a talent in math or science. His paper on quasi-perfect numbers—which the 17-year-old Lander proved exist only in theory—won him the Westinghouse Prize. His work at Princeton, where he received his undergraduate degree in mathematics, earned him a Rhodes scholarship at Oxford University. There, Lander completed his graduate degree in pure mathematics. He was well on his way to living his life as a chalk-stained mathematician, but he realized something was missing. “I loved pure mathematics,” says Lander. “But I didn’t want to make it a life.”

“Mathematics is kind of monastic,” he notes. “It’s a very lonely and individual pursuit. And I’m not a very good monk. I like doing things with people.”

This connection with people set into motion the series of happy accidents that would eventually draw Lander into a biology lab. When Lander returned from Oxford, a Princeton professor sent Lander’s résumé to a statistician at Harvard’s School of Public Health, who passed it along to someone at the Business School. Lander was offered a job at Harvard—teaching economics. “I knew no economics whatsoever,” he admits. “But I figured you can learn that stuff.”

Lander was a quick study and a decent teacher, but economics did not provide him with the intellectual stimulation he needed. Fortunately, his little brother did. Arthur Lander, a neuroscientist by training, sent his sibling some papers about mathematical neurobiology. Lander realized that he couldn’t fully understand the research until he learned a bit more about neurobiology. And he couldn’t handle the neurobiology without studying some cell biology, which he couldn’t grasp until he tackled molecular biology. So Lander opted to audit a biology course at Harvard and spent his evenings cloning fruit fly genes in the lab. “I essentially picked up biology on the street corner,” he says with a smile. Of course, in Cambridge—home of Harvard and the Massachusetts Institute of Technology—people who hang out on street corners are just as likely to be discussing biology as anything else.

After a lecture one night, Lander ran into David Botstein, a geneticist at MIT who had developed methods for scanning the genome to find an individual gene that may play a role in disease. He was hoping next to develop a means to untangle the genetics behind more complex human disorders that are thought to arise from subtle disturbances in dozens or hundreds of genes—cancer, diabetes, schizophrenia, even obesity.

The two got to arguing (as good New Yorkers will) about how statistics could be used to search for the genes involved in complex human diseases. Soon, they had the outline of a solution. Lander secured a position as a fellow at the Whitehead Institute for Biomedical Research, where he set to work on the problem. The appointment was a bit unusual—Lander was still a professor at the Harvard Business School—but he made enough progress to receive a MacArthur fellowship for his efforts.

Now a geneticist, Lander joined MIT as a tenured faculty member and a year later he launched the Whitehead Institute/MIT Center for Genome Research, becoming director of one of the first genome sequencing centers in the world. “It was a chaotic career path,” notes Lander. “But everything worked out okay.”

As head of the center, Lander helped build a series of maps that show the basic layout of the human and mouse genomes. In addition to providing the scaffolding needed to assemble the full human genome sequence, completed last year, these maps have proved useful for pinpointing the location of genes involved in disease. For Lander, that’s what his efforts are all about. “Disease is my motivation,” he says. “All the information about one’s risk for disease is hiding in the genome. The goal is to tease out that information.

“A cell already knows what it will be, what it will do,” he adds. “So it’s just a matter of persuading the cell to tell us what it knows.” Lander knows how to be persuasive. Already he and his colleagues at the Whitehead Institute have teased out genes involved in diabetes and gained knowledge that will help scientists diagnose and treat cancers. Whitehead researchers have produced approximately one-third of the human genome sequence. But prying the secrets from the human genome is work that is really just beginning.

The first problem: The human genome is big. Imagine someone dumping 1,000 volumes of the Encyclopaedia Britannica in your living room, says Lander. “How would you tackle all that information? Would you read all the spines first? Or would you start at ‘aardvark’ and go from there?”

But size isn’t the only obstacle. The human genome is also written in code. Scientists are still learning how to decipher the information encrypted in the 3 billion letters that provide the instructions for assembling and operating a human being. The human genome may represent a “book of life,” but it is not yet an open book.

“Looking at the genome is not like looking down at Earth from space and seeing all the clouds and oceans,” says Lander. “You have to think of the questions you want to ask. And then you have to figure out how to ask them.

“That’s my main job,” says Lander. “Thinking about the questions.”

Asking these questions often requires new techniques. And for someone who loves data, who wants answers, the waiting can be the hardest part. “Most days are spent just getting things ready,” says Lander. “So you have to be reasonably good at delayed gratification.” For example, before Lander and his team could build a map of the human genome, they spent months developing new biochemical procedures, new robotics, and new analytical software. “Once everything was in place, making the map was fun.”

Biology may involve a lot of grunt work—certainly more than mathematics does—but Lander doesn’t seem to mind. “The highs, when they come, are better than anything you could imagine.

“Getting to pursue new ideas and new directions, always thinking about new things—it’s intoxicating, it’s addicting,” he says. “I could never give it up.”




Laureates 2012 – 2012 Future – Genome Research


Founder, Chairman, and President of the J. Craig Venter Institute, Rockville, MD and La Jolla, CA, USA and CEO of Synthetic Genomics Inc., La Jolla, CA, USA.

Dr. J. Craig Venter has made numerous contributions to genomics—from ESTs and the first genome of a living species, to the human genome and environmental genomics, to the most recent accomplishments of constructing the first synthetic bacterial cell.

Venter’s initial efforts focused on identifying human genes through random cDNA sequencing (through the use of expressed sequence tags or ESTs) which identified fragments of about half the human genes in his 1995 publication.

Venter led the group that produced the first full sequence of a bacterium, H. influenza, using their whole genome shotgun approach. Five years later, Venter co-founded a company, Celera Genomics, to extend the whole genome shotgun method with newly developed algorithms and instrumentation to sequence the drosophila, human, mouse, rat and mosquito genomes. His group published a draft human sequence simultaneously with the publicly-funded Human Genome Project in 2001.

Venter went on to apply high-throughput sequencing to ocean microbial populations and the human gut, contributing greatly to the rapidly expanding field of metagenomics. More recently, Venter has focused much of his group’s efforts on synthetic genomics, first synthesizing the phix-174 viral genome and transplanting the genome of M. mycoides into a cell of a related species. In 2010 he and the team combined those two technologies, using synthetic oligo-nucleotides to recreate a 1.1 million base pair bacterial genome, and placed it in a new host, thereby constructing the largest synthetically made genome and the first synthetic bacterial cell.

Dr. Venter has received numerous awards and honors including: The 2008 National Medal of Science; Washington, DC, Member, National Academy of Sciences, Washington, DC; Member of the American Society of Microbiology; Honorary Doctor of Science – Syracuse University; the Benjamin Rush Medal – College of William and Mary, VA; Honorary Doctor of Science – Mount Sinai School of Medicine, New York; Scientist of the Year – ARCS Foundation, San Diego; Doctor of Science Honoris Causa – University of Melbourne; Doctorat Honoris Causa – University of Montreal; Doctor of Science Honoris Causa – Imperial College, London; Scripps Institute of Oceanography Nierenberg Prize, La Jolla, CA; Honorary Doctor of Science, Chung Yuan University, Taipei; Presidential Distinguished Scientific Award; World Health Award, Presented by Mikhail Gorbachev, World Awards, Vienna, Austria; University College London Prize in Clinical Science – London, England; Honorary Doctor of Technology, Royal Institute of Technology, Stockholm, Sweden; Medal of the Presidency, Italian Republic, Rimini, Italy; Prince of Asturias Award for Technical and Scientific Research; Fellow, American Academy of Arts and Sciences, Washington, DC; and the Exceptional Service Award for Exploring Genomes.




Laureates 2012 – 2012 Future – Genome Research


Anthony B. Evnin Professor of Genomics; Director, Lewis-Sigler Institute for Integrative Genomics; Director, Certificate Program in Quantitative and Computational Biology, Princeton University, Princeton, NJ, USA

Prof. David Botstein has been the intellectual leader of genomics since its inception. He created modern human genetics, championed the Human Genome Project, devised microarrays to exploit genome information for the global assessment of gene expression and has fostered systems biology. He has mentored numerous young scientists in the field, first at MIT, later at Stanford and most recently at Princeton.

Botstein’s 1980 paper “Construction of a Genetic Linkage Map in Man Using Restriction Fragment Length Polymorphisms” was the first to explicitly argue that it would be possible to build a sufficiently dense map of markers through the human genome to permit the mapping of disease genes in families by monitoring the transmission of those markers and disease status through the families. The vision outlined in this paper provided not only the clearest early motivation for the initiation of the human genome project, but its clarity and beauty drew many scientists into the field of genomics.

Following these seminal contributions he has been an intellectual participant in many of the most important key developments in genomics, the most prominent examples of which are: a) the development along with Pat Brown of methods to measure and statistically analyze gene expression profiles and apply these methods to the identification of subtypes of cancer. It would be impossible to overstate the impact of this work both in terms of basic biological research and the direction of thinking about molecular taxonomies of disease;  b) articulation of the need to organize genes into biological groupings to permit systematic pathway analyses, and the initiation of generic systems to do so.   Interestingly, these last areas are clear antecedents of what is now coming to be known as systems biology and which David Botstein is again one of the key intellectual figures.
Among Prof. Botstein’s awards and honors are: Member of the US National Academy of Sciences, the Eli Lilly and Company Award in Microbiology, the Genetics Society of America Medal, the Allen Award of the American Society of Human Genetics, and the Gruber Prize in Genetics.



Laureates 2011 – 2011 Past – Evolution


Professor, Department of Biology, Stanford University, Stanford, CA, USA

Prof. Feldman has produced conceptual results of broad interest in the domain of animal and plant evolution. His work has led to highly focused insights of cultural significance such as the out-of-Africa model of human evolution, as well as cultural preferences in different civilizations. His work not only explores basic scientific topics, but investigates the societal consequences of the conclusions he draws in terms of models of evolution.

Prof. Feldman originated the quantitative theory of genetic modifiers of recombination, mutation, and dispersal. His work was the first to show that the pattern of interactions among genes determined whether sex would evolve.

With Cavalli-Sforza, he originated the quantitative theory of cultural evolution. The application of this theory to the culture of son preference in China, and his work on the significance of male/female birth ratio in that country, seems likely to have very important social management consequences, leading to attempts by the Chinese authorities to reduce this preference.

Prof. Feldman demonstrated that today’s world wide pattern of genomic variation is largely due to the sequence of human migrations over the 60,000 years since modern humans left Africa. His finding that about 10 percent of genomic variation is between continents has inspired much of the subsequent discussion on the meaning of race.

Prof. Feldman and collaborators originated “niche construction,” a generalization of evolutionary theory that stresses the feedbacks between organismic evolution and environmental dynamics, demonstrating via his model that phenotypes have a much more active role in evolution than previously thought. This has profoundly influenced subsequent work in evolutionary ecology.

Feldman’s findings have triggered the development of new scientific fields in both the humanities and life sciences. He sheds light on many key issues of evolution, including hominid evolution and the evolution of culture. Feldman has done much demographic work on trends important to humanity’s future.

Among Marcus Feldman’s honors are Elected Fellow, American Association for the Advancement of Science; Elected Member, American Academy of Arts and Sciences; Doctor Pholosophiae Honoris Causa, Hebrew University Jerusalem; Doctor Philosophiae Honoris Causa, Tel Aviv University; member of the editorial boards of various scientific journals; and a member of various international committees and foundations.




Laureates 2011 – 2011 Future – Ageing-Facing the Challenge


Professor of Genetics, Department of Molecular Biology, Massachusetts General Hospital, Harvard University

Gary Ruvkun has made a major contribution to the future of human health with the discovery of conserved hormonal signaling pathways with universal influence on animal aging. He is a key figure in defining the genetic basis for human health during aging with his discovery of a core set of hormonal signals and signaling pathways that regulate aging and lifespan in animal models, that are likely to act in humans as well.

In a series of reports starting in the early 1990s Ruvkun defined an insulin signaling pathway that regulates aging in the C. elegans worm and showed that the essential elements of this pathway are conserved in mice and humans. He discovered that like mammals, C. elegans uses an insulin-like signaling pathway to control its metabolism and longevity, suggesting that insulin-like regulation of longevity and metabolism is ancient and universal.

The Ruvkun lab discovered the molecular identity of the many genes in the pathway, including the daf-2insulin receptor, the many insulins that act upstream of the daf-2 receptor, the signal transduction components downstream of the insulin receptor such as age-1, daf-18, pdk-1, akt-1, and akt-2, and the downstream transcription factors daf-16 and daf-3, to reveal the signaling pathway from hormone to membrane receptor to the gene expression changes in the nucleus that regulate metabolism and longevity. Their finding by that the DAF-16/FoxO transcription factor is coupled to insulin signaling via conserved interactions with the kinases AKT and PDK also points to these transcriptional cascades as key in metabolic responses to insulin. This finding has been important for understanding the defects in diabetes as well as for aging research, since the mammalian orthologs of daf-16, the FoxO transcription factors, are regulated by insulin and are emerging now as key outputs of insulin signaling.

Recent insulin signaling mutant analyses in mouse and humans have validated the generality of these discoveries to other animals. Not surprisingly, an insulin-like pathway is now a major theme in animal aging regulation, with many reports of insulin-like regulation of lifespan in Drosophila, mouse, and even human beginning to emerge.

This work had an enormous impact on aging research relevant to longevity and later-life health. These findings catalyzed developments across biogerontology by defining hormone interventions with direct relevance to clinical practice and drug development.

Ruvkun is now using RNAi screens and comparative genomics to reveal the downstream genes regulated by insulin signaling. He discovered a connection between longevity and small RNA pathways, with the production of specific small RNA factors induced in long lived mutant animals.

Among Gary Ruvkun’s awards are: Benjamin Franklin Medal, Franklin Institute; Albert Lasker Award for Basic Medical Research; member of the American Academy of Arts and Sciences; and member of the National Academy of Sciences.




Laureates 2005 – 2005 Future – Materials Science – Tissue Engineering


Robert Langer is the Kenneth L. Germeshausen Professor of Chemical and Biomedical Engineering at the Massachusetts Institute of Technology, USA.

Prof. Langer has pioneered the field of biomaterials and tissue engineering. He has contributed to the development of biocompatible polymers for drug delivery and synthetic polymers to form specific tissue structures creating the field of tissue engineering. His work has allowed the controlled release of macromolecules using biocompatible polymers.

Prof. Langer is also responsible for the creation of numerous novel biomaterials, such as shape memory polymers and materials with switchable surfaces, aerosols and microchips. His work has led to the development of synthetic polymers to deliver cells to form specific tissue structures.

He has been a prolific contributor to this new field of materials science. He has mentored numerous students and post docs who have themselves become leaders in the field.

In 2002 he was awarded the Charles Stark Draper Prize of the NAE. He has won numerous other awards and is one of the few people who have been elected to all three US National Academies (Science, Engineering and Medicine).




Laureates 2002 – 2002 Future – Life Sciences


Prof. Robert H. Waterston (born 1943 in Michigan, USA) obtained a bachelor’s degree in engineering from Princeton University in 1965 and received both a medical degree and a doctorate in pathology from the University of Chicago in 1972. After a postdoctoral fellowship at the Medical Research Council Laboratory of Molecular Biology in Cambridge, England, Prof. Waterston joined the Washington University faculty in 1976. He is James S. McDonnel Professor of Genetics, head of the Department of Genetics, and director of the School of Medicine’s Genome Sequencing Center, which he founded in 1993. The center was a principal member of the International Human Genome Sequencing Consortium, the public effort to complete the working draft.

He was a recipient of an American Heart Association Established Investigator Award from 1980 to 1985, and held a John Simon Guggenheim Fellowship from 1985 to 1986. He has served as a member of several NIH study sections and as chairman of the NIH’s Molecular Cytology Study Section. He currently serves on the NIH Advisory Council.

Prof. Waterston is a member of Sigma Xi, Alpha Omega Alpha, the Genetics Society and the American Society of Cell Biology. He has published more than 70 peer-reviewed scientific articles.

“It’s powerful information, and the potential benefits are enormous,” Prof. Waterston says. “We all have a responsibility to educate ourselves about the issues. To realize its great promise, scientific information of this sort must be available in an unrestricted form to citizens and scientists everywhere.” 

“For the next hundred years, scientists will use these foundations to make increasingly detailed discoveries about how human beings and other organisms work,” says geneticist Robert H. Waterston of the advances in genetics research. “As a result, more and more will be understood about all aspects of human health, behavior, and disease – and ultimately about therapy and prevention.”



Laureates 2002 – 2002 Future – Life Sciences


subsequently received the Nobel Prize for Medicine in 2002.

Sir John Sulston graduated from Cambridge University in 1963. After completing his Ph.D. on the chemical synthesis of DNA, he moved to the USA to study prebiotic chemistry (the origins of life on Earth). In 1969, Sir John joined Sydney Brenner’s group at the Medical Research Council Laboratory of Molecular Biology in Cambridge where he studied the biology and genetics of the nematode worm, Caenorhabditis elegans. He and his team collaborated with Bob Waterston at Washington University in the USA to sequence the genome of this model organism. In 1992, Sir Sulston was appointed the first Director of the Sanger Centre in Cambridgeshire, which is behind the UK’s contribution to the international Human Genome Project. He stepped down as Director in September 2000.

Sir John Sulston is co-author with Georgina Ferry of The Common Thread: A Story of Science, Politics, Ethics and the Human Genome, to be published by Bantam Press in February 2002. The book tells the story of the sequencing of the human genome from the point of view of one of its leading figures, and discusses what the achievement means for future medical treatments and our understanding of ourselves. In light of the recent ‘gene rush’ by companies to stake claims to parts of the genome, the authors argue that the information it contains should be freely available for the benefit of all, and not carved up for private profit. “The human genome will be the foundation of biology for decades, centuries or millennia to come”.



Laureates 2002 – 2002 Future – Life Sciences


subsequently received the Nobel Prize for Medicine in 2002.

Prof. Sydney Brenner’s sustained contributions during the course of a scientific career spanning 40 years are exceptional both in their novelty and in their impact on biology.

During 1957 – 1973, he provided fundamental insights into the genetic code. In 1957, he produced a theoretical paper that presented a formal demonstration of the impossibility of all overlapping codes, insisting that further efforts in deciphering the genetic code be restricted to non-overlapping codes. In 1961 he, together with Francis Crick and others, published evidence for the triphet nature of the genetic code deduced from the frame-shift mutagenesis experiments, which remain a tour de force. He published, together with Fran?ois Jacob and Matthew Meselson, their discovery of messenger RNA, a finding that provided fundamental insights into translation of the genetic code. In 1964 and succeeding years, Prof. Brenner and others published a demonstration of the colinearity of a gene and deciphered nonsense codons by genetics. During the mid-1960s Prof. Brenner, together with Fran?ois Jacob and Fran?ois Cuzin, established the fundamental principles underlying the regulation of DNA replication in E coli. From 1974 to 1990, Prof. Brenner and his colleagues introduced the eukaryotic model C. elegans and demonstrated its utility for studying development. He developed the genetic methodology for dissecting the organism’s developmental program, especially of the nervous system. His students have proved the wisdom of his choice by extending the model to aging and apoptosis. Now that the genome sequence of C. elegans is complete, the usefulness of this system is greatly enhanced. During the 1980s and 1990s, Prof. Brenner made great political and scientific contributions to the establishment of recombinant NDA technology in general and to the human genome project in particular. Among other things, he introduced the study of the putter fish, one of the very few vertebrate organisms to have very little “junk” DNA.

Prof. Sydney Brenner was born in South Africa on 13 January 1927 and studied medicine and science at the University of Witwatersrand, Johannesburg . He went on to Oxford, working in the Physical Chemistry Laboratory, and and receiveed a degree of D.Phil. in 1952. After a brief return to South Africa, he joined the MRC Unit in the Cavendish Laboratory at Cambridge in 1956. He worked here and in its successor, the MRC Laboratory of Molecular Biology at Cambridge, where he was Director from 1979 to 1987. In 1987 he became Director of the MRC Unit of Molecular Genetics, retiring in 1992 from the MRC. He is now Director of the Molecular Sciences Institute, a private research institute in Berkeley, California.

Last year, aged 74, Prof. Brenner accepted an offer to become a research professor at the Salk Institute for Biological Studies. He said: “I don’t want to retire to play golf. Science is one’s hobby and one’s work and one’s pleasure.”


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Reporter and Curator: Dr. Sudipta Saha, Ph.D.


Negative selection was examined using two measures that highlight different periods of selection in the human genome. The first measure, inter-species, pan-mammalian constraint (GERP-based scores; 24 mammals) addresses selection during mammalian evolution. The second measure is intra-species constraint estimated from the numbers of variants discovered in human populations using data from the 1000 Genomes project and covers selection over human evolution.

For DNaseI elements and bound motifs most sets of elements show enrichment in pan mammalian constraint and decreased human population diversity, though for some cell types the DNaseI sites do not appear overall to be subject to pan-mammalian constraint. Bound TF motifs have a natural control from the set of TF motif with equal sequence potential for binding but without binding evidence from ChIP-seq experiments; in all cases, the bound motifs showed both more mammalian constraint and higher suppression of human diversity.

Consistent with previous findings, genome-wide evidence was not observed for pan-mammalian selection of novel RNA sequences. There are also a large number of elements without mammalian constraint, between 17-90% for TF-binding regions as well as DHSs and FAIRE regions. Previous studies could not determine whether these sequences are either biochemically active, but with little overall impact on the organism, or are under lineage specific selection. By isolating sequences preferentially inserted into the primate lineage, which is only feasible given the genome-wide scale of this data, this issue was specifically examined. The majority of primate-specific sequence is due to retrotransposon activity, but an appreciable proportion is non-repetitive primate-specific sequence. Of 104,343,413 primate-specific bases (excluding repetitive elements), 67,769,372 (65%) are found within ENCODE-identified elements. Examination of 227,688 variants segregating in these primate specific regions revealed that all classes of elements (RNA and regulatory) show depressed derived allele frequencies, consistent with recent negative selection occurring in at least some of these regions. This suggests that an appreciable proportion of the unconstrained elements are lineage specific elements required for organismal function, consistent with long standing views of recent evolution, and the remainder are likely to be “neutral” elements which are not currently under selection, but may still affect cellular or larger scale phenotypes without an effect on fitness.

The binding patterns of TFs are not uniform, and can be correlated both inter-and intra-species measures of negative selection with the overall information content of motif positions. The selection on some motif positions is as high as protein coding exons. These aggregate measures across motifs show that the binding preferences found in the population of sites are also relevant to the per-site behavior. By developing a per-site metric of population effect on bound motifs, it was found that highly constrained bound instances across mammals are able to buffer the impact of individual variation.

It was proposed to express the deleterious effect of TFBS mutations in terms of mutational load, a known population genetics metric that combines the frequency of mutation with predicted phenotypic consequences that it causes. This metric was adapted to use the reduction in PWM score associated with a mutation as a crude but computable measure of such phenotypic consequences. It was not assumed that TFBS load at a given site reduces an individual’s biological fitness. Rather, it was argued that binding sites that tolerate a higher load are less functionally constrained. This approach, although undoubtedly a crude one, makes it possible to consistently estimate TFBS constraints for different TFs and even different organisms and ask why TFBS mutations are tolerated differently in different contexts.

It was first asked whether motif load would be able to detect the expected link between evolutionary and individual variation. A published metric was used, Branch Length Score (BLS), to characterise the evolutionary conservation of a motif instance. This metric utilises both a PWM based model of the conservation of bases and allows for motif movement. Reassuringly, mutational load correlated with BLS in both species, with evolutionary non-conserved motifs (BLS=0) showing by far the highest degree of variation in the population. At the same time, ∼40% of human and fly TFBSs with an appreciable load (L>5e-3) still mapped to reasonably conserved sites (BLS>0.2, ∼50% percentile in both organisms), demonstrating that score-reducing mutations at evolutionary preserved sequences can be tolerated in these populations.

Using this metric, the original findings were confirmed, suggesting that TFBSs with higher PWM scores are generally more functionally constrained compared to ‘weaker’ sites. The fraction of detected sites mapping to bound regions remained similar across the whole analysed score range, suggesting that this relationship is unlikely to be an artefact of higher false-positive rates at ‘weaker’ sites. This global observation, however, does not rule out the possibility that a weaker match at some sites is specifically preserved to ensure dose-specific TF binding. This may be the case, for example, for Drosophila Bric-à-brac motifs, which exhibited no correlation between motif load and PWM score, consistent with the known dosage-dependent function of Bric-à-brac in embryo patterning.

Motif load was used to address whether TFBSs proximal to transcription start sites (TSS) are more constrained compared to more distant regulatory regions. This was found to be the case in the human, but not in Drosophila. CTCF binding sites in both species were a notable exception, tolerating the lowest mutational load at locations 500bp-1kb from TSS, but not closer to the TSS, suggesting that the putative role of CTCF in establishing chromatin domains is particularly important in proximity of gene promoters.

To gain further insight into the functional effects of TFBS mutations, a dataset was used that mapped human CTCF binding sites across four individuals. TFBS mutations detected in this dataset often did not result in a significant loss of binding, with ∼75% mutated sites retaining at least two thirds of the binding signal. This was particularly prominent at conserved sites (BLS>0.5), 90% of which showed this ‘buffering’ effect. To address whether buffering could be explained solely by the flexibility of CTCF sequence preferences, it was analysed between-allele differences in the PWM score at polymorphic binding sites. As expected, globally CTCF binding signal correlated with the PWM score of the underlying motifs. Consistent with this, alleles with minor differences in PWM match generally had little effect on the binding signal compared to sites with larger PWM score changes, suggesting that the PWM model adequately describes the functional constraints of CTCF binding sites. At the same time, it was found that CTCF binding signals could be maintained even in those cases, where mutations resulted in significant changes of PWM score, particularly at evolutionary conserved sites. A linear interaction model confirmed that the effect of motif mutations on CTCF binding was significantly reduced with increasing conservation. These effects were not due to the presence of additional CTCF motifs (as 96% of bound regions only contained a single motif), while differences between more and less conserved sites could not be explained away by differences in the PWM scores of their major alleles. A CTCF dataset from three additional individuals generated by a different laboratory yielded consistent conclusions, suggesting that our observations were not due to over-fitting.

Taken together, CTCF binding data for multiple individuals show that mutations can be buffered to maintain the levels of binding signal, particularly at highly conserved sites, and this effect cannot be explained solely by the flexibility of CTCF’s sequence consensus. It was asked whether mechanisms potentially accountable for such buffering would also affect the relationship between sequence and binding in the absence of mutations. Training an interaction linear model across the whole set of mapped CTCF binding sites revealed that conservation consistently weakens the relationship between PWM score and the binding intensity. Thus, CTCF binding to evolutionary conserved sites may generally have a reduced dependence on sequence.

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