On December 22, 2015, the results of research on yak domestication carried out by the State Key Laboratory of Grassland and Agro-ecosystems SKLGAE (Lanzhou University) and the School of Life Science of Lanzhou University (LZU) was published on Nature Communications, an internationally renowned academic journal. Qiu Qiang, Wang Lizhong, Wang Kun and Yang Yong are the first author of the paper, and Professor Liu Jianquan is the corresponding author. The publishing of the paper received extensive attention from dozens of news media, including the Technology Daily, China Science Daily, Guangming Daily Online, People’s Daily Online, sohu.com and so on.
In the research, a detailed analysis of the genetic variation of wild and domestic yaks and the influence of artificial selection on the domestic yaks’ genomes is carried out according to a map of whole-genome genetic variation from 14 million yak genomes established on the basis of the genome database of the wild and domestic yaks. The research detects about 200 genes of domestic yaks with signals of selection, several of which relates to behavior and tameness. Through the reconstruction of the population dynamics and population differentiation of yak domestication, the researchers date yak domestication to 7,300 years before present (yr BP) and an estimated six-fold increase in yak population size by 3,600 yr BP. The dates of yak domestication and the massive growth of domestic yaks coincide with two early human population expansions on the Qinghai-Tibet Plateau (QTP) detected according to the genetics data of human population. Part of the nomadic population on the QTP still lives on raising domestic yaks in a nomadic way and lives at high-altitude regions. Yak domestication enables some nomadic people to survive on the QTP without seasonal transfer. The massive growth of domestic yaks highly relates to the introduction of agricultural technology, designated settlements depending on agriculture and the growth of human population. It shows that the yak domestication plays a critical role on human’s permanent living on the QTP and the social stability and development.
The research is funded by the National Natural Science Foundation of China, Ministry of Science and the Ministry of Education.
Over the past ten years and more, Professor Liu Jianquan, together with the other members of the research group collected representative individuals of every yak species in the yak breeding zones and acquired enough wild yak samples at Hoh Xil. The systematic analysis on the altitude adaptation and domestication genetic mechanism of yaks with new technologies and new analytical methods provides important basis for the usage of yak genetic resources, improvement of varieties and understanding of the genetic effects of domestic yaks. The group has a series of high-level research papers published on such international journals as Nature Genetics, Molecular Biology and Evolution， Journal of Biogeography, Molecular Ecology Resources, Animal Genetics and so on.
(Translated by Wei Xianchao; proofread by Sissi Xu)
