The Horse Genome

For some time now, scientists have been at work sequencing the DNA of many animals, including the cow, the dog, the chimpanzee, and just a few weeks ago, the horse. According to an article in The Economist, "With it emerged further evidence of how horses have been close human companions, and, like other mammals that share an evolutionary history with man, how they could help explain the understanding of hereditary diseases."

There was also a surprise discovery that has to do with the makeup of chromosome 11, which features a developing centromere--the center area of the chromosome that has heretofore been difficult to isolate. According to the article, "The apprearance of a new centromere, therefore, lets geneticists examine the process by which new chromosomes come into existence." In the scientific world, this is a very big deal because it indicates that in the which came first debate regarding repetitive DNA and centromeres, centromeres came first.

In addition, the horse genome reveals how extensive crossbreeding was in the development of the breed as well as the fact that 53% of horse genes appear in the same order on their chromosome as they do in humans. This is even more than dogs where the figure is only 29%.

One particular promising area of research involves the genetic mutation that is responsible for night blindness, prevalent in Appaloosas. It turns out that the markings for night blindness also reside in an area of the genome that is responsible for coat markings. Identification of this marking may prove to be relevant to humans suffering from the condition. As the article points out: "The dog may be man's best friend, but his horse may thus prove to be more genetically helpful."