VentureBeat

Posts Tagged ‘SNPs’

23andme-logo.pngFirst, it was self-described 23andMe investor Martin Varsavsky who spilled some early information about the secretive personal-genomics startup founded by Sergey Brin’s new wife, Anne Wojcicki, and now backed by Google and Genentech. (See our coverage here.) Now more details about 23andMe’s plans to help individuals map their own genomes are emerging, courtesy of Illumina, a gene-scanning company partnered with the startup.

At an investor conference yesterday, Illumina CEO Jay Flatley sketched out 23andMe’s plans and even reviewed its first product, Forbes’ Matthew Herper reports. (The meeting was Webcast here.)

The fundamentals aren’t too different from what Varsavsky has described previously. 23andMe customers will take a DNA sample — Flatley suggests it could involve either saliva or a cheek swab — and send it in to Illumina for genotyping. Instead of scanning the whole genome letter-by-letter, Illumina’s microbead-based scanners detect hundreds of single-letter DNA variations that give a useful but rough approximation of what the full genome would look like. (The upside is that scanning for these variations, technically known as single-nucleotide polymorphisms, or SNPs, is far faster and cheaper than reading through the entire genome.) 23andMe would then throw that information up on a secure Web page, where users could then analyze it to their hearts’ content.

Flatley said 23andMe’s initial emphasis will be on ancestry, although it seems likely that disease-related SNPs are also likely to get a lot of attention, particularly given how scientists have successfully used similar gene scans to identify dozens of disease-related SNPs over the past year. (See our previous coverage here.) Flatley said he’s already tried out the service and now keeps his own genotype on his iPhone, although he didn’t say much about what he learned from it — in sharp contrast to, say, Craig Venter.

Perhaps most interesting, Flatley then passed out sign-up cards for 23andMe and said anyone who registered on the spot could get the service for free, although Herper doesn’t say how many folks took him up on the offer. According to Flatley, 23andMe will start to show off their software over the next few months — which will be none too soon, given that at least one competitor, Navigenics, is also on the march. (Our coverage is here.) Rumors of yet a third, still stealthy, personal-genomics startup are also swirling around the Valley.

double-helix-genomegov.jpgScientists yesterday reported finding seven new gene variants linked to diabetes, a sign that the disease-gene hunt may have finally attained a sort of critical momentum.

Researchers have been looking for genes related to particular disorders for more than 30 years, and have been frustrated in that hunt for almost as long. With the exception of a few conditions caused by a single malfunctioning gene — most notably, perhaps, cystic fibrosis and Huntingdon’s disease — most disease appears to result from a complex interplay of multiple genetic effects and environmental factors. Even worse, until recently most studies that tried to untangle the genetic side of the equation operated by laborious trial-and-error — researchers would study families or other groups of people with a particular disease, then apply various biochemical and mathematical tools to try to identify which portions of the genome they shared, in the hopes that they’d eventually narrow the search down to a particular gene. The process produced so many unproven — and largely inaccurate — “candidate” genes that biologists began to joke about “gene of the week” discoveries.

One of the major changes in recent years has been the advent of a new way of sifting through genetic data. Instead of sequencing entire genomes — or even chunks of genomes — researchers have started restricting their searches to the specific ways in which one individual’s genes differ from those of other people. Think of it this way: Sequencing a human genome involves reading all three billion nucleotide “letters” of it, the overwhelming majority of which are the same from person to person. But if you set two — or eight, or 500 — genomes next to one another, the places where individual “letters” vary will jump out. Researchers have now mapped 10 million or so of these genetic variations, which are technically known as single-nucleotide polymorphisms, or SNPs (pronounced “snips”), and compiled them into a database known as the HapMap. (One private biotech, Perlegen Sciences, donated at least 2.1 million SNPs it had discovered to the project.)

In other words, sorting through SNPs is a lot faster than trolling through entire genomes, which in turn makes it possible to scan genetic information from much larger groups of people with a particular disease. In practice, these techniques may finally be turning disease-association studies into more of a science than an art.

Unfortunately, that doesn’t mean that medical breakthroughs are likely to flow immediately from the resulting gene-disease links. The latest diabetes findings raise the number of genes that contribute to the disease to ten — but those ten genes only account for two to 20 percent of overall diabetes risk. What’s more, it’s not entirely clear what these gene variants do differently that might contribute to the disease, much less how modern medicine might go about preventing or repairing the damage. So there’s plenty of slogging yet to be done.

The NYT’s Nicolas Wade has more.

Top Stories

Recent Comments

Powered by Disqus

Featured Guest Columnists

Job Board

Links

Venturebeat Writers

  • For advertising, contact .
  • Log in

Font Size