Click to join our Facebook Fan Page and follow us on Twitter!
By Michael Price for Sciencemag.org
Great Danes stretch more than a meter from paw to shoulder and can easily weigh more than 90 kilograms. A Chihuahua fits snugly inside a purse. Domestic dog breeds are more varied in body size and shape—not to mention coat color and fur length—than any other land-based mammal. Yet, according to a new study, a mere two to six regions in doggy DNA account for most of this diversity.
Over the past few years, researchers have linked a number of canine traits—from size to coiffure—to specific mutations in dog DNA. This new line of research was made possible by the completion of the Dog Genome Project in 2005 by the National Human Genome Research Institute (NHGRI) in Bethesda, Maryland. But researchers lacked a large-scale analysis of these traits across a wide variety of breeds. As a result, they didn’t know whether traits were governed by a large number of genetic regions, each contributing a small effect, or by a few regions with large effects.
So a team led by Carlos Bustamante, a comparative geneticist at Stanford University in Palo Alto, California, and Elaine Ostrander, a comparative geneticist with NHGRI, analyzed genetic information from 915 domestic dogs representing 80 different breeds. The researchers compared the dogs’ DNA, looking for sequences that differed by a single base, known as single-nucleotide polymorphisms. Once they found out where the DNA differed, they compared those differences between dogs with, for example, short versus long legs or perky versus droopy ears.
To read the rest click here.
