
08/30/2025
Roughly five thousand years ago on the Eurasian steppe, people began selecting horses not only for their strength but also for traits hidden in their DNA. A new genomic study points to two key regions of the horse genome that may have determined which animals could be saddled and steered. One gene, ZFPM1, influences anxiety and stress in other species. Its rise suggests early breeders favored calmer, more manageable animals.
The second, GSDMC, appears tied to the shape and stability of the spine. When this variant spread between 4,700 and 4,200 years ago, horses likely developed stronger backs and sturdier forelimbs. Such changes would have made them better able to carry a rider, a development that transformed human mobility and warfare. Ludovic Orlando, who led the research team, explained that the rapid spread of these traits shows how quickly people recognized and reinforced them through breeding.
Archaeological traces of early saddling and wear on horse teeth line up with the genetic timeline. The match between the physical record and the DNA record provides a compelling case that humans were deliberately shaping the rideability of horses at the dawn of the Bronze Age. While other genes and cultural innovations surely played a part, this discovery helps explain why wild herds became the trusted partners that carried humans across continents and into history.