Tracing the genetic origin of mane growth in domestic horses: an innovative model to identify genetic factors that regulate hair growth

The mane of the domestic horse grows as human head hair practically indefinitely. Extant wild equid species (Equus ferus) and other closely related species of the Equidae family have a short upright mane. The origin and biological function of the horse mane is unknown. We hypothesize that the origin of the horse mane is the result of artificial selection of hair growth mutants by people during domestication; therefore, the aim of this project is to identify these mutations.

Horses provide an innovative model for mapping hair growth mutations as they display an extraordinary variation in this trait as well as have a favourable population structure for gene mapping experiments. Another major advantage of using the horse as a model for mapping growing hair is that there are other related species of the Equidae family that carry the original genetic variant (ancestral haplotype) to compare with. These are three species of zebra, wild donkeys and the Przewalski's horse, all of which have a short upright man.

We are planning to use Icelandic horses in a genome scan for gene discovery. Andalusian horses and Tinker horses will be analysed to validate the results. These breeds are well known for variation in length and thickness of the mane. Zebra, wild donkeys and the Przewalski's horse will be analysed to compare with the original genetic variant.

The information from the study will provide valuable knowledge about the origin of the mane in horses and genes that regulate hair growth. This information can be helpful in different disorders of hair loss in other animals and humans.

Collaborations

The project is conducted in close collaboration with professor Juan José Negro Balmaseda and his research team at The Doñana Biological Station in Spain.