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Category Archives: Transhuman News

Cancer genome analysis of breast cancer: Team identifies genetic causes and similarity to ovarian cancer

Posted: September 24, 2012 at 12:10 pm

ScienceDaily (Sep. 23, 2012) A team of scientists with The Cancer Genome Atlas program reports their genetic characterization of 800 breast tumors, including finding some of the genetic causes of the most common forms of breast cancer, providing clues for new therapeutic targets, and identifying a molecular similarity between one sub-type of breast cancer and ovarian cancer.

Their findings, which offer a more comprehensive understanding of the mechanisms behind each sub-type of breast cancer, are reported in the Sept. 23, 2012 online edition of the journal Nature.

The researchers, including a large group from the University of North Carolina at Chapel Hill, analyzed tumors using two basic approaches: first, using an unbiased and genome-wide approach, and second, within the context of four previously known molecular sub-types of breast cancer: HER2-enriched, Luminal A, Luminal B and Basal-like. Both approaches arrived at the same conclusions, which suggest that even when given the tremendous genetic diversity of breast cancers, four main subtypes were observed. This study is also the first to integrate information from six analytic technologies, thus providing new insights into these previously defined disease subtypes.

Charles Perou, PhD, corresponding author of the paper, says, "Through the use of multiple different technologies, we were able to collect the most complete picture of breast cancer diversity ever. These studies have important implications for all breast cancer patients and confirm a large number of our previous findings. In particular, we now have a much better picture of the genetic causes of the most common form of breast cancer, namely Estrogen-Receptor positive/Luminal A disease. We also found a stunning similarity between Basal-like breast cancers and ovarian cancers."

"This study has now provided a near complete framework for the genetic causes of breast cancer, which will significantly impact clinical medicine in the coming years as these genetic markers are evaluated as possible markers of therapeutic responsiveness."

Dr. Perou is the May Goldman Shaw Distinguished Professor of Molecular Oncology and a member of UNC Lineberger Comprehensive Cancer Center.

Among the many discoveries include findings of some of the likely genetic causes of the most common form of breast cancer, which is the Estrogen-Receptor positive Luminal A subtype. Luminal A tumors are the number one cause of breast cancer deaths in the USA accounting for approximately 40 percent, and thus, finding the genetic drivers of this subtype is of paramount importance. The TCGA team found that the mutation diversity within this group was the greatest, and that even specific types of mutations within individual genes, were associated with the Luminal A subtype. Some of these mutations may be directly targetable by a drug(s) that is in clinical development, thus possibly offering new options for many patients.

In addition, the team compared basal-like breast tumors (also known as triple-negative breast cancers) with high-grade serous ovarian tumors and found many similarities at the molecular level, suggesting a related origin and similar therapeutic opportunities. These data also suggest that basal-like breast cancer should be considered a different disease than ER-positive/Luminal breast cancer, and in fact, both basal-like breast cancer and ovarian cancer were more similar to each other than either was to ER-positive/Luminal breast cancer.

Dr. Perou adds, "Cancer is, of course, a complex disease that includes many types of alterations, and thus, no one technology can identify all of these alteration; however, by using such a diverse and powerful set of technologies in a coordinated fashion, we were able to identify the vast majority of these alterations."

Katherine Hoadley, PhD, study co-author, explains, "Our ability to compare and integrate data from RNA, microRNA, mutations, protein, DNA methylation, and DNA copy number gave us a multitude of insights about breast cancer. In particular, highlighting how distinct basal-like breast cancers are from all other breast cancers on all data types. These findings suggest that basal-like breast cancer, while arising in the same anatomical location, is potentially a completely different disease."

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Cancer genome analysis of breast cancer: Team identifies genetic causes and similarity to ovarian cancer

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UNC Lineberger scientists lead cancer genome analysis of breast cancer

Posted: at 12:10 pm

Public release date: 23-Sep-2012 [ | E-mail | Share ]

Contact: Dianne G. Shaw dgs@med.unc.edu 919-966-7834 University of North Carolina Health Care

A team of scientists with The Cancer Genome Atlas program reports their genetic characterization of 800 breast tumors, including finding some of the genetic causes of the most common forms of breast cancer, providing clues for new therapeutic targets, and identifying a molecular similarity between one sub-type of breast cancer and ovarian cancer.

Their findings, which offer a more comprehensive understanding of the mechanisms behind each sub-type of breast cancer, are reported in the September 23, 2012 online edition of the journal Nature.

The researchers, including a large group from the University of North Carolina at Chapel Hill, analyzed tumors using two basic approaches: first, using an unbiased and genome-wide approach, and second, within the context of four previously known molecular sub-types of breast cancer: HER2-enriched, Luminal A, Luminal B and Basal-like. Both approaches arrived at the same conclusions, which suggest that even when given the tremendous genetic diversity of breast cancers, four main subtypes were observed. This study is also the first to integrate information from six analytic technologies, thus providing new insights into these previously defined disease subtypes.

Charles Perou, PhD, corresponding author of the paper, says, "Through the use of multiple different technologies, we were able to collect the most complete picture of breast cancer diversity ever. These studies have important implications for all breast cancer patients and confirm a large number of our previous findings. In particular, we now have a much better picture of the genetic causes of the most common form of breast cancer, namely Estrogen-Receptor positive/Luminal A disease. We also found a stunning similarity between Basal-like breast cancers and ovarian cancers."

"This study has now provided a near complete framework for the genetic causes of breast cancer, which will significantly impact clinical medicine in the coming years as these genetic markers are evaluated as possible markers of therapeutic responsiveness."

Dr. Perou is the May Goldman Shaw Distinguished Professor of Molecular Oncology and a member of UNC Lineberger Comprehensive Cancer Center.

Among the many discoveries include findings of some of the likely genetic causes of the most common form of breast cancer, which is the Estrogen-Receptor positive Luminal A subtype. Luminal A tumors are the number one cause of breast cancer deaths in the USA accounting for approximately 40 percent, and thus, finding the genetic drivers of this subtype is of paramount importance. The TCGA team found that the mutation diversity within this group was the greatest, and that even specific types of mutations within individual genes, were associated with the Luminal A subtype. Some of these mutations may be directly targetable by a drug(s) that is in clinical development, thus possibly offering new options for many patients.

In addition, the team compared basal-like breast tumors (also known as triple-negative breast cancers) with high-grade serous ovarian tumors and found many similarities at the molecular level, suggesting a related origin and similar therapeutic opportunities. These data also suggest that basal-like breast cancer should be considered a different disease than ER-positive/Luminal breast cancer, and in fact, both basal-like breast cancer and ovarian cancer were more similar to each other than either was to ER-positive/Luminal breast cancer.

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UNC Lineberger scientists lead cancer genome analysis of breast cancer

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Jon Stewart Hilariously Accepts 10th Consecutive Emmy for Best Variety Series

Posted: at 12:10 pm

video

The last time another show won the Emmy for Outstanding Variety, Music or Comedy Series, its competition included ABCs Politically Incorrect, Bill Mahers previous broadcast gig.

That was in 2002, and in every Emmy show after that, Comedy Centrals The Daily Show has been victorious.

Tonight was no exception as Jon Stewart and crew accepted their tenth consecutive Emmy, beating out sister program The Colbert Report, Mahers HBO show, Saturday Night Live, and late-night talk shows from Jimmy Fallon and Jimmy Kimmel.

Presenter Ricky Gervais joked not again as he announced that The Daily Show had won. Stewart was then restrained by Colbert and Fallon, who were upset at losing out.

And as expected, Stewart delivered on some comedy in his speech, taking a swipe at the predictability of the Emmy Awards when, in the future, aliens discover a box of these [trophies].

Watch Stewarts dramatic stage entrance and speech below, via ABC:

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Explore Human Limits @ Wellcome Collection

Posted: at 12:10 pm

This is a sponsored post on behalf of Wellcome Collection.

Join a special symposium inspired by the Superhuman exhibition exploring the capabilities and possibilities of human bodies and minds.

Human Limits will open up discussion around our relationship with technology past and present drawing on science fiction and science fact, questioning our desire to explore new environments and imagining future humans.

It starts off sociably on Friday with an opportunity to explore the exhibition after hours, mingle over drinks and watch silent film Aelita: Queen of Mars, one of the first films to depict space travel, accompanied by a live band, Minima.

On Saturday a roster of top speakers talk about how science and medicine have changed the way we look at ourselves, the impact electricity has had on our lives, science fiction and space exploration, the implications and future possibilities for enhancing human bodies and whether cross-channel swimmers are, in fact, superhuman.

All this plus breaks for refreshments, networking, chit chat and lunch thrown in.

Human Limits is on Friday 28 September from 7-9.30pm and Saturday 29 September from 10.30am-5pm. Tickets 30 full price/25 concessions for both days, including drinks on Friday evening and lunch, tea and coffee on Saturday. To book, please call 020 7611 2222.

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Explore Human Limits @ Wellcome Collection

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Humanity isn’t, it becomes | Gene Expression

Posted: at 12:10 pm

John Hawks prompts to reemphasize an aspect of my thinking which has undergone a revolution over the past 10 years. I pointed to it in my post on the Khoe-San. In short, the common anatomically modern human ancestors of Khoe-San and non-Khoe-San may not have been people. Rather, people may have evolved over the past 100-200,000 years ago. Of course the term people is not quite as scientific as you might like. In philosophy and law you have debates about personhood. Granting the utility of these debates I am basically saying that the common ancestor of Khoe-San and non-Khoe-San may not have been persons, as well understand them. Though, as a person myself, I do think they were persons. At this point I am willing to push the class person rather far back in time.

As I suggested earlier there is an implicit assumption that personhood is a shared derived trait of our species. Or at least it is a consensus today that all extant members of H. sapiens are persons. Since Khoe-San are persons, the common ancestor of Khoe-San and non-Khoe-San must also be persons if personhood is a shared derived trait. But, we also know that there are many aspects of realized personhood on a sociological or cultural scale which seem to diminish the further back in time you go. For example, the Oldowan lithic technology persisted for ~1 million years. A common modern conception of persons is that persons in the aggregate are simply never so static. Persons have culture, and culture is protean. Therefore, one might infer from the nature of Oldowan technological torpor that the producers of that technology were not persons.

But theres a large gap between the decline of the Oldowan and the rise of anatomically modern humans. Where to draw the line? Lets take a step back about a decade. Heres an extract from Richard Kleins excellent Dawn of Human Culture:

Our third and final observation is that the relationship between anatomical and behavioral change shifted abruptly about 50,000 years ago. Before this time, anatomy and behavior appear to have evolved more or less in tandem, very slowly, but after this time anatomy remained relatively stable while behavioral (cultural) change accelerated rapidly. What could explain this better than a neural change that promoted the extraordinary modern human ability to innovate? This is not to say that Neanderthals and their non-modern contemporaries possessed ape-like brains or that they were as biologically and behaviorally primitive as yet earlier humans. It is only to suggest that an acknowledged genetic link between anatomy and behavior in yet earlier people persisted until the emergence of fully modern ones, and that that postulated genetic change 50,000 years ago fostered the uniquely modern ability to adapt to a remarkable range of natural and social circumstances with little or no physiological change.

Arguably, the last key neural change promoted the modern capacity for rapidly spoken phonemic language, or for what anthropologists Duane Quiatt and Richard Milo have called a fully vocal language, phenmiized, syntactical, and infinitely open and productive.

The non-moderns were not ape-like, but they were clearly not human-like, if they lacked language as what we understand language to be. Today this view is likely in the minority position, but why? I think the possibility of admixture between these distinct human lineages suggests that the gap between them and us was not quite as large Klein postulates above. And even then there is a major problem with Kleins thesis: there was mitochondrial and archaeological evidence even then that the divergence of the Khoe-San and non-Africans far pre-dated the 50,000 year time period alluded to above. Since then the evidence has become even stronger that the divergence of the Khoe-San from other humans, and likely Africans from non-Africans, pre-dates the emergence of behavioral modernity.

An implicit assumption that personhood is a shared derived trait from a common human ancestor to me speaks to the same needs and urges which posit a specific ensoulment or creation of humanity from clay. Our minds are not very good at continuities, so we must create distinctive breaks. One moment an animal, and another moment a man! The occasional scientist who speculates that there may be a set of genes which define humanity I think falls into the trap of assuming discontinuity where there is none. There may be no genetic variant necessary or sufficient to being a human. Let me finish by quoting John Hawks, who inspired me to be a bit more explicit in my own line of thinking:

Personally, I think that cognitive modernity is a red herring. Todays people learn some kinds of technical and symbolic complexity that were never present in ancient peoples. Somepeople living today in Western cultures, despite all our educational efforts, fail to attain levels of technical knowledge that are regular outcomes for the majority of people in the same environment. Human performance varies continuously.

I assert that it is unreasonable to suppose that Neandertals had a stupid gene. If so, it should be just as unreasonable to suppose that a smart gene could explain the evolution of human cognition during the last 100,000 years. These unrealistic assumptions are widespread, and impede our understanding just as thoroughly as assumptions about the nature of biological species impeded our understanding of Neandertal ancestry of living human populations. Some archaeologists have concluded that Neandertal cognition is an either/or proposition. Some look at Neandertals, find a lack of evidence that they behave identically to later people, and conclude that the Neandertals were therefore unquestionably cognitive inferiors. Others look at Neandertals, find some signs of modern-like behaviors, and conclude that Neandertals were therefore unquestionably our cognitive equals.

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DNA helps Wyckoff police nab 'motorcycle burglar'

Posted: September 22, 2012 at 11:18 pm

WYCKOFF Police arrested a man known they called the "motorcycle burglar" this morning after matching him to DNA found at one of his victim's homes.

According to Wyckoff Chief Benjamin Fox, officers responded to a Nancy Lane residence in July 2011 after a homeowner reported that approximately $3,000 worth of jewelry had gone missing from her home.

A neighbor had observed a man activating an alarm system as he fled the home, and the man rode past the homeowner on a motorcycle as she was arriving home.

During an investigation, police found droplets of blood inside the home, along with a crowbar and a pair of latex gloves that had been discarded as the man rode away on the motorcycle, Fox said. They then matched DNA samples from the blood and gloves to 51-year-old Lee Malsch of Paterson, whose extensive criminal history included past burglaries.

Police obtained a warrant for Malsch's arrest on Sept. 11, but had trouble locating him. With the help of the Passaic County Sheriff's Department, however, they were able to find him this morning and take him into custody.

He was charged with burglary and theft, and is currently awaiting a bail hearing at the Bergen County Jail in Hackensack.

Fox praised the work of the investigating officers, saying that burglaries can often be difficult to solve.

"My guys don't solve every crime. No department does. But when they have evidence to works ith, they do everything that they can to apprehend those responsible," he said. "That's what they did here, and this community should be grateful."

Police were unable to recover any of the jewelry stolen from the home in 2011.

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DNA helps Wyckoff police nab 'motorcycle burglar'

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NASA: Dragon prepared for space flight

Posted: at 8:14 am

Published: Sept. 21, 2012 at 6:22 PM

HOUSTON, Sept. 21 (UPI) -- NASA says the first contracted cargo resupply flight to the International Space Station is targeted for early next month in Florida.

NASA and Space Exploration Technologies Corp. said the Falcon 9 rocket and its Dragon cargo spacecraft are ready for the SpaceX CRS-1 mission Oct. 7 from Cape Canaveral Air Force Station. A backup launch opportunity is available Oct. 8.

"The launch of the Dragon spacecraft will be the first of 12 contracted flights by SpaceX to resupply the space station and marks the second trip by a Dragon to the station, following a successful demonstration mission in May," NASA said Thursday in a release. "SpaceX services under the [Commercial Resupply Services] contract will restore an American capability to deliver and return significant amounts of cargo, including science experiments, to the orbiting laboratory -- a feat not achievable since the retirement of the space shuttle."

NASA said the Dragon will be filled with about 1,000 pounds of supplies and will return with about 734 pounds of scientific materials, as well as about 504 pounds of space station hardware.

Dragon is scheduled to return in late October for a parachute-assisted splashdown in the Pacific Ocean off the coast of Southern California.

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SpaceX, NASA target Oct. 7 launch for resupply mission to International Space Station

Posted: at 8:14 am

ScienceDaily (Sep. 21, 2012) NASA managers, Space Exploration Technologies Corp. (SpaceX) officials and international partner representatives Thursday announced Sunday, Oct. 7, as the target launch date for the first contracted cargo resupply flight to the International Space Station under NASA's Commercial Resupply Services (CRS) contract.

International Space Station Program managers confirmed the status and readiness of the Falcon 9 rocket and its Dragon cargo spacecraft for the SpaceX CRS-1 mission, as well as the space station's readiness to receive Dragon.

Launch is scheduled for 8:34 p.m. EDT from Space Launch Complex 40 at Cape Canaveral Air Force Station in Florida. A back up launch opportunity is available on Oct. 8.

The launch of the Dragon spacecraft will be the first of 12 contracted flights by SpaceX to resupply the space station and marks the second trip by a Dragon to the station, following a successful demonstration mission in May. SpaceX services under the CRS contract will restore an American capability to deliver and return significant amounts of cargo, including science experiments, to the orbiting laboratory -- a feat not achievable since the retirement of the space shuttle.

The Dragon will be filled with about 1,000 pounds of supplies. This includes critical materials to support the 166 investigations planned for the station's Expedition 33 crew, including 63 new investigations. The Dragon will return about 734 pounds of scientific materials, including results from human research, biotechnology, materials and educational experiments, as well as about 504 pounds of space station hardware.

Materials being launched on Dragon will support experiments in plant cell biology, human biotechnology and various materials technology demonstrations, among others. One experiment, called Micro 6, will examine the effects of microgravity on the opportunistic yeast Candida albicans, which is present on all humans. Another experiment, called Resist Tubule, will evaluate how microgravity affects the growth of cell walls in a plant called Arabidopsis. About 50 percent of the energy expended by terrestrial-bound plants is dedicated to structural support to overcome gravity. Understanding how the genes that control this energy expenditure operate in microgravity could have implications for future genetically modified plants and food supply. Both Micro 6 and Resist Tubule will return with the Dragon at the end of its mission.

Expedition 33 Commander Sunita Williams of NASA and Aki Hoshide of the Japan Aerospace Exploration Agency will use a robot arm to grapple the Dragon following its rendezvous with the station on Wednesday, Oct. 10. They will attach the Dragon to the Earth-facing port of the station's Harmony module for a few weeks while crew members unload cargo and load experiment samples for return to Earth.

Dragon is scheduled to return in late October for a parachute-assisted splashdown in the Pacific Ocean off the coast of southern California.

While NASA works with U.S. industry partners to develop commercial spaceflight capabilities, the agency also is developing the Orion spacecraft and the Space Launch System (SLS), a crew capsule and heavy-lift rocket to provide an entirely new capability for human exploration. Designed to be flexible for launching spacecraft for crew and cargo missions, SLS and Orion will expand human presence beyond low Earth orbit and enable new missions of exploration across the solar system.

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SpaceX, NASA target Oct. 7 launch for resupply mission to International Space Station

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SpaceX launch to space station is Oct. 7

Posted: at 8:14 am

A private space capsule's first contracted cargo mission to the International Space Station is slated to launch Oct. 7, NASA officials announced Thursday.

SpaceX's robotic Dragon spacecraft is set to blast off atop the company's Falcon 9 rocket from Florida's Cape Canaveral Air Force Station at 8:34 p.m. EDT on Oct. 7. A backup launch opportunity is available the following day, officials said.

The mission will kick off Dragon's first-ever bona fide supply run to the station. California-based SpaceX holds a $1.6 billion NASA contract to make 12 such unmanned flights.

When it leaves the pad, Dragon will be carrying about 1,000 pounds (454 kilograms) of supplies, officials said. Much of the gear will support the 166 different scientific investigations including experiments in plant cell biology, human biotechnology and materials demonstrations planned during the station's current Expedition 33.

If all goes according to plan, Dragon will rendezvous with the station on Oct. 10, at which point Expedition 33 commander Sunita Williams of NASA and Japanese astronaut Aki Hoshide will grapple it with the orbiting lab's robotic arm.

Dragon will stay attached to the Earth-facing port of the station's Harmony module for several weeks while the Expedition 33 crew unloads the capsule and then loads it back up again with cargo to return to Earth.

Dragon is scheduled to depart the station in late October. It will splash down in the Pacific Ocean, carrying 734 pounds (333 kg) of scientific materials and 504 pounds (229 kg) of space station hardware, officials said.

The Oct. 7 flight won't mark Dragon's maiden mission to the $100 billion orbiting complex.

In May, Dragon became the first private vehicle ever to visit the station during a historic demonstration mission that sought to gauge SpaceX's readiness to begin its contracted flights.

NASA also inked a $1.9 billion deal with Virginia-based Orbital Sciences Corp. to make eight unmanned supply runs to the station with its Cygnus spacecraft and Antares rocket.

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Novel approach for single molecule electronic DNA sequencing

Posted: at 8:14 am

ScienceDaily (Sep. 21, 2012) DNA sequencing is the driving force behind key discoveries in medicine and biology. For instance, the complete sequence of an individual's genome provides important markers and guidelines for medical diagnostics and healthcare. Up to now, the major roadblock has been the cost and speed of obtaining highly accurate DNA sequences. While numerous advances have been made in the last 10 years, most current high-throughput sequencing instruments depend on optical techniques for the detection of the four building blocks of DNA: A, C, G and T. To further advance the measurement capability, electronic DNA sequencing of an ensemble of DNA templates has also been developed.

Recently, it has been shown that DNA can be threaded through protein nanoscale pores under an applied electric current to produce electronic signals at single molecule level. However, because the four nucleotides are very similar in their chemical structures, they cannot easily be distinguished using this technique. Thus, the research and development of a single-molecule electronic DNA sequencing platform is the most active area of investigation and has the potential to produce a hand-held DNA sequencer capable of deciphering the genome for personalized medicine and basic biomedical research.

A team of researchers at Columbia University, headed by Dr. Jingyue Ju (the Samuel Ruben-Peter G. Viele Professor of Engineering, Professor of Chemical Engineering and Pharmacology, Director of the Center for Genome Technology and Biomolecular Engineering), with colleagues at the National Institute of Standards and Technology (NIST) led by Dr. John Kasianowicz (Fellow of the American Physical Society), have developed a novel approach to potentially sequence DNA in nanopores electronically at single molecule level with single-base resolution. This work, entitled "PEG-Labeled Nucleotides and Nanopore Detection for Single Molecule DNA Sequencing by Synthesis" is now available in the open access online journal Scientific Reports, from Nature Publishing Group.

The reported nanopore-based sequencing by synthesis (Nano-SBS) strategy can accurately distinguish four DNA bases by detecting 4 different sized tags released from 5'-phosphate-modified nucleotides at the single molecule level for sequence determination. The basic principle of the Nano-SBS strategy is described as follows. As each nucleotide analog is incorporated into the growing DNA strand during the polymerase reaction, its tag is released by phosphodiester bond formation. The tags will enter a nanopore in the order of their release, producing unique ionic current blockade signatures due to their distinct chemical structures, thereby determining DNA sequence electronically at single molecule level with single base resolution.

As proof-of-principle, the research team attached four different length polymer tags to the terminal phosphate of 2'-deoxyguanosine-5'-tetraphosphate (a modified DNA building block) and demonstrated efficient incorporation of the nucleotide analogs during the polymerase reaction, as well as better than baseline discrimination among the four tags at single molecule level based on their nanopore ionic current blockade signatures. This approach coupled with polymerase attached to the nanopores in an array format should yield a single-molecule electronic Nano-SBS platform.

In previous work, the Center of Genome Technology & Biomolecular Engineering at Columbia University, led by Professor Ju and Dr. Nicholas J. Turro (William P. Schweitzer Professor of Chemistry), developed a four-color DNA sequencing by synthesis (SBS) platform using cleavable fluorescent nucleotide reversible terminators (NRT), which is licensed to Intelligent Bio-Systems, Inc., a QIAGEN company. SBS with cleavable fluorescent NRTs is the dominant approach used in the next generation DNA sequencing systems. Dr. Kasianowicz and his group at NIST pioneered the investigation of nanopores for single molecule analysis. They previously reported that different length polymers, polyethylene glycols (PEGs), could be distinguished by their unique effects on current readings in a -hemolysin protein nanopores at single molecule level and subsequently developed a theory for the method. Their results provide the proof-of-concept for single molecule mass spectrometry. The combination of the SBS concept with the distinct nanopore-detectable electronic tags to label DNA building blocks led to the development of the single-molecule electronic Nano-SBS approach described the current Scientific Reports article (09/21/2012).

As lead author Dr. Shiv Kumar points out, "The novelty of our approach lies in the design and use of four differently tagged nucleotides, which upon incorporation by DNA polymerase, release four different size tags that are distinguished from each other at the single molecule level when they pass through the nanopore. This approach overcomes any constraints imposed by the small differences among the four nucleotides, a challenge which most nanopore sequencing methods have faced for decades." Moreover, the technique is quite flexible; with PEG tags as prototypes, other chemical tags can be chosen to provide optimal separation in different nanopore systems.

With further development of this Nano-SBS approach, such as the use of large arrays of protein or solid nanopores, this system has the potential to accurately sequence an entire human genome rapidly and at low cost, thereby enabling it to be used in routine medical diagnoses.

The authors of the Scientific Reports article were Shiv Kumar, Chuanjuan Tao, Minchen Chien, Brittney Hellner, Arvind Balijepalli, Joseph W.F. Robertson, Zengmin Li, James J. Russo, Joseph E. Reiner, John J. Kasianowicz, and Jingyue Ju. The study was supported by a grant from the National Institutes of Health, a National Research Council/NIST/NIH Research Fellowship, and a grant from the NIST Office of Law Enforcement Standards.

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