Horse genome

The horse genome was first sequenced in 2006. This means scientists figured out the exact order of all the tiny building blocks that make up a horse's DNA. They mapped 2.7 billion DNA base pairs, and released the full map in 2009. The horse genome is bigger than the dog genome but smaller than the human genome or the bovine genome.

Because horses share over 90 hereditary diseases with humans, studying the horse genome helps both horse and human health. Nearly half of the chromosomes in the horse genome match up with human chromosomes in a special way, called synteny. This helps scientists learn about diseases in both species. The project cost $15 million and was funded by groups like the National Human Genome Research Institute and the National Institutes of Health.

The first horse to have its genome fully sequenced was a Thoroughbred mare named Twilight. Researchers also studied many other horse breeds to learn about genetic differences. In 2012, another horse named Sugar had her genome sequenced, revealing millions of genetic differences from Twilight. This helps scientists understand how genes affect a horse's traits and health.