A Genetic Road Map

Using your DNA as a GPS system seems a bit far-fetched in today's scientific world, but researchers at the University of California did exactly that. Taking DNS from over 1000 people of European descent, they mapped out the diverse genetic history onto a grid. The outcome surprised everyone.

"The result was a map of Europe-- fuzzy, but unmistakable. 'I couldn't believe the picture was so clear,' says Carlos Bustamante, senior author and statistical geneticist at Cornell University. 'I, for one, fell off my chair.' Italy and Spain clearly had their own cluster of genetically similar individuals, for example, and there were even distinctions between French-, German-, and Italian- speaking populations within Switzerland." According to Bustamante, these results make sense. Due to shared language and geographical closeness, it is much more likely to marry and mate with someone from a similar gene pool because of their proximity on the globe. The physics law of "like-repels-like" does not necessarily apply with humans.

Using single nucleotide polymorphisms (SNPs) that reveal subtle differences from person to person, the research team assembled their test subjects and made a genetic map of Europe. The use of SNPs is becoming more commonplace because of the ability to help reveal genetic risk factors such as heart disease and diabetes, or help investigators catch a suspect in a recent Anthrax case (http://sciencenow.sciencemag.org/cgi/content/full/2008/812/1). This genography mapping could lead to a number of practical applications for those searching for their ancestral heritage. It could also open new doors for forensic scientists to identify victims of crime and catch suspects using their own DNA. 

Although people have long speculated that genes were related to geography, such detailed proof has never before been displayed. The SNPs can reveal the minute differences between Europeans, but Paolo Menozzi, an evolutionary geneticist at the University of Parma in Italy, cautions that, "overall, Europeans' genetics do not vary vastly from country to country." On a whole, "their genes are much more similar than they are different," he says. 

http://allsciencetime.blogspot.com/2008/09/genography-puts-european-ancestry-on.html