Until the other day, I’d never heard of a haplogroup. But the concept is essential to our understanding of where horses came from.
Simply (or not-so-simply, depending on your scientific bent), a haplogroup is defined by a set of characteristic mutations on the mitochondrial genome and can be traced along a maternal line, right back to the original “mother.”
The first complete mitochondrial DNA sequence of the horse was reported in 1994. Now, a research team headed by Alessandro Achilli, from the department of cellular and environmental biology at the University of Perugia in Italy, has made a breakthrough discovery. Analyzing equine mitochondrial DNA (which is inherited solely from the mother), the team has discovered how many horse haplogroups exist as well as identified the Ancestral Mare Mitogenome. You can read the full article here.
If you’re not up to that, let me give you the highlights. There are 18 major haplogroups (and one of those is only found in E. przewalskii — the sole remaining wild horse). There is an Ancestral Mare Mitogenome and it dates back to approximately 130,000 to 160,000 years ago. By comparison, modern humans first evolved about 200,000 years ago
The genetic clusters suggest that horses were domesticated multiple times, in different places, possibly to preserve the species during glacial catastrophes. At least one domestication occurred in Western Europe, possibly in the Iberian Peninsula.
“The very fact that many wild mares have been independently domesticated in different places testifies to how significant horses have been to humankind,” says Achilli. “It means that the ability of taming these animals was badly needed by different groups of people in different regions of Eurasia, from the Asian steppes to Western Europe, since they could generate the food surplus necessary to support the growth of human populations and the capability to expand and adapt into new environments or facilitate transportation.”
What’s to be done with this new information? The authors of the report suggest that it can be used to classify well-preserved remains, reassess the haplogroup variations of modern breeds and help evaluate the role of genetics in racehorse performance.
Whatever the future brings, it’s nice to know that when it comes to horses, we go together and it’s been that way for a long, long time.