Nov. 5 (HealthDay News) -- The genome of the domestic horse has been sequenced, an accomplishment that will improve the breeding of horses and may help studies of human health, according to an international team of researchers.

"Having access to multiple genome sequences makes it easier to understand all genomes, including our own. By looking at the horse genome, we can better understand human biology and human diseases," James Murray, a professor of animal science at the University of California, Davis, said in a news release. He has worked on the Horse Genome Project since it began in 1995.

More than 90 hereditary conditions affect both humans and horses, such as infertility, inflammatory diseases and muscle disorders. By studying the horse genome, it may be possible to increase understanding of these diseases in humans, Murray noted.

The researchers found that the horse genome is larger than the dog genome and smaller than the human and cow genomes. They also found that 17 out of 32 (53 percent) of horse chromosome pairs are composed of material from a single human chromosome, compared with 29 percent of dog chromosome pairs. This means that fewer chromosome rearrangements separate humans from horses than separate humans from dogs.

The scientists also found an evolutionary new centromere on horse chromosome 11. Centromeres allow movement of chromosomes when cells divide, which ensures normal distribution of all genetic material to each daughter cell. The newly identified centromere in the horse may help improve understanding about how centromeres function, the researchers pointed out.

The sequencing project findings will be unveiled in the Nov. 6 issue of Science.

SOURCE: University of California-Davis, news release, Nov. 5, 2009