Saturday, December 8, 2012

Gene-tracing project gets an upgrade

Where did your ancestors come from? What's your genetic lineage? The Genographic Project is answering these questions and more. And in doing so, it is solving the riddle of who we are and how we're all related.

By Alan Boyle

Seven years ago, National Geographic launched a project aimed at using genetic analysis to map tens of thousands of years of human migration ? and now a new phase of the Genographic Project promises to bring even more precision to that map.

"With the number of markers we've added, we've gotten much closer to the present," the project's director, population geneticist Spencer Wells, told me this week.


The key to tracing genetic connections lies in chemical markers?? specific strings of DNA coding that are passed down from one generation to the next. When the Genographic Project was founded in 2005, scientists tracked 12 markers on the Y chromosome of male participants, or about 150 markers in the mitochondrial DNA of men or women. The Y-chromosome DNA could track only the paternal lineage, and the mitochondrial DNA readings could track only the maternal line.?

Genographic 2.0 has kicked it up a notch: A testing tool known as the "GenoChip" has been custom-designed for this second phase of the project.?Now the project looks at 12,000 DNA markers on the Y-chromosome, 3,300 mitochondrial DNA markers, and 130,000 other markers from each participants' genome. Such a huge database could theoretically correlate your genetic heritage with your ancestors' regional ramblings, even if they're not on the direct paternal or maternal line, Wells said.

The data analysis even correlates your genetic information with that of the long-extinct Neanderthal and Denisovan species of near-humans. Researchers have found that non-Africans can trace up to 4 percent of their genetic makeup back to the Neanderthals, and that modern-day Papuans owe about 6 percent of their genetic heritage to the mysterious Denisovans. So how much of a Neanderthal are you? Genographic 2.0 could let you know.

"Your own DNA tells an incredible story of how your ancestors embarked on an epic journey that populated the earth," Wells explains in a video about Geno 2.0.

The testing routine is relatively simple, if a bit pricey: First, you purchase a mail-order sample kit for $199.95. When you receive the kit, you run a cotton swab around the inside of your cheek to pick up some of your cells, then seal up the swabs and send them back to the lab. A few weeks later, you can review your results on a password-protected Web site.?

Geno 2.0 isn't the only gene-sampling program that's out there: Several companies offer Y-chromosome or mitochondrial-DNA testing from genealogical purposes. In fact, Geno 2.0 is partnering with one of those companies, Family Tree DNA, to provide the cheek-swab testing service. Other companies such as 23andMe and Complete Genomics?can sample a wider swath of your genome, or even your entire genome. (23andMe also gives you percentages for Neanderthal DNA, by the way.)

Wells' project is different in that genealogy is not Geno 2.0's primary purpose, and the genetic markers are not linked to medically relevant traits. So you can't use the results to calculate your risk of falling prey to disease. But you can get a sense of where your long-ago ancestors came from, in what percentages. For example, oceanographer Robert Ballard discovered that his mostly Dutch-British genome is also about 2 percent Oceanian, connecting him with the seafarers who plied Pacific waters tens of thousands of years ago.

National Geographic

Population geneticist Spencer Wells, director of National Geographic's Genographic Project, says the latest phase of the project should provide new opportunities for citizen scientists as well as professional researchers.

Even though Geno 2.0 is not a family-tree project per se, it's still possible to compare your genetic profile with others via the project's community forum. "We display people who have genetic profiles similar to yours as 'dots' in your circle," Wells said. You can "ping" those dots to ask other Genographic participants for more information about their heritage.

"This allows them to remain fairly anonymous, and yet share their story," Wells said.

Wells and his colleagues are also awarding grants, to fund research using Geno 2.0's anonymized genetic database as well as to support initiatives for indigenous and traditional communities around the world. The Genographic Project has already provided 62 Legacy Fund grants, worth $1.7 million, for initiatives in locales ranging from Guatemala to Nepal. There's also an education program called GenoThreads, which aims to connect classrooms around the world via email and videoconferencing. The first GenoThreads project is connecting high-school students in Switzerland and Singapore.

More than half a million people participated in the first phase of the Genographic Project, which distributed the testing kits for $99. Geno 2.0 is twice the price ? which has sparked a few critical comments from Geno 1.0 participants.

"We bought this for our son and the results were vague ... like we started in? Africa. Yeah, everybody did," one commenter wrote in a posting on National Geographic's YouTube page. "Then some of our line went to East Asia and some went West. Then the info stops. Oh, unless we want to buy Phase Two for $199. This was very disappointing."

I've had my DNA tested for several projects in the past, including Family Tree DNA as well as Geno 1.0, and although the tests have helped me exclude some suspects in the family search, I haven't yet hit the genealogical jackpot. Genetic testing has identified unexpected connections between other Boyle kin, however, so I know the technology works. Maybe I'll give Geno 2.0 a try and file a follow-up report. In the meantime, feel free to let me know how your own genetic quest is turning out.

More from the Genographic Project:


Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's?Facebook page, following?@b0yle on Twitter?and adding the?Cosmic Log page?to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out?"The Case for Pluto,"?my book about the controversial dwarf planet and the search for new worlds.

Source: http://cosmiclog.nbcnews.com/_news/2012/12/06/15707737-gene-tracing-project-gets-an-upgrade?lite

baby found alive in morgue rockies ashley judd second degree murders bobby petrino brian dunn vin scully

No comments:

Post a Comment

Note: Only a member of this blog may post a comment.