Prehistoric genomes reveal the genetic foundation and cost of horse domestication

作者：Mikkel Schubert, Hákon Jónsson, Dan Chang, Clio Der Sarkissian, Luca Ermini, Aurélien Ginolhac, Anders Albrechtsen, Isabelle Dupanloup, Adrien Foucal, Bent Petersen, Matteo Fumagalli, Maanasa Raghavan, Andaine Seguin‐Orlando, Thorfinn Sand Korneliussen, Amhed Missael Vargas Velazquez, Jesper Stenderup, Cindi A. Hoover, Carl‐Johan Rubin, Ahmed Alfarhan, Saleh A. Alquraishi, Khaled A. S. Al‐Rasheid, David E. MacHugh, Ted Kalbfleisch, James N. MacLeod, Edward M. Rubin, Thomas Sicheritz‐Pontén, Leif Andersson, Michael Hofreiter, Tomàs Marquès‐Bonet, M. Thomas P. Gilbert, Rasmus Nielsen, Laurent Excoffier, Eske Willerslev, Beth Shapiro, Ludovic Orlando · 发表于：Proceedings of the National Academy of Sciences · 年份：2014 · DOI：10.1073/pnas.1416991111 · 被引用次数：354 · 研究领域：Genetic and phenotypic traits in livestock、Genetic diversity and population structure、Genetic Mapping and Diversity in Plants and Animals

The domestication of the horse ∼ 5.5 kya and the emergence of mounted riding, chariotry, and cavalry dramatically transformed human civilization. However, the genetics underlying horse domestication are difficult to reconstruct, given the near extinction of wild horses. We therefore sequenced two ancient horse genomes from Taymyr, Russia (at 7.4- and 24.3-fold coverage), both predating the earliest archeological evidence of domestication. We compared these genomes with genomes of domesticated horses and the wild Przewalski's horse and found genetic structure within Eurasia in the Late Pleistocene, with the ancient population contributing significantly to the genetic variation of domesticated breeds. We furthermore identified a conservative set of 125 potential domestication targets using four complementary scans for genes that have undergone positive selection. One group of genes is involved in muscular and limb development, articular junctions, and the cardiac system, and may represent physiological adaptations to human utilization. A second group consists of genes with cognitive functions, including social behavior, learning capabilities, fear response, and agreeableness, which may have been key for taming horses. We also found that domestication is associated with inbreeding and an excess of deleterious mutations. This genetic load is in line with the "cost of domestication" hypothesis also reported for rice, tomatoes, and dogs, and it is generally attributed to the relaxa...