학술논문

Whole-Genome Resequencing of Worldwide Wild and Domestic Sheep Elucidates Genetic Diversity, Introgression, and Agronomically Important Loci
Document Type
Academic Journal
Source
Molecular Biology and Evolution. February, 2022, Vol. 39 Issue 2
Subject
Iran
Middle East
Southeast Asia
India
East Asia
China
United Kingdom
Language
English
ISSN
0737-4038
Abstract
Domestic sheep and their wild relatives harbor substantial genetic variants that can form the backbone of molecular breeding, but their genome landscapes remain understudied. Here, we present a comprehensive genome resource for wild ovine species, landraces and improved breeds of domestic sheep, comprising high-coverage (~16.10x) whole genomes of 810 samples from 7 wild species and 158 diverse domestic populations. We detected, in total, ~121.2 million single nucleotide polymorphisms, ~61 million of which are novel. Some display significant (P < 0.001) differences in frequency between wild and domestic species, or are private to continent-wide or individual sheep populations. Retained or introgressed wild gene variants in domestic populations have contributed to local adaptation, such as the variation in the HBB associated with plateau adaptation. We identified novel and previously reported targets of selection on morphological and agronomic traits such as stature, horn, tail configuration, and wool fineness. We explored the genetic basis of wool fineness and unveiled a novel mutation (chr25: T7,068,586C) in the 30-UTR of IRF2BP2 as plausible causal variant for fleece fiber diameter. We reconstructed prehistorical migrations from the Near Eastern domestication center to South-and-Southeast Asia and found two main waves of migrations across the Eurasian Steppe and the Iranian Plateau in the Early and Late Bronze Ages. Our findings refine our understanding of genome variation as shaped by continental migrations, introgression, adaptation, and selection of sheep. Key words: whole-genome sequences, genetic diversity, adaptive introgression, genetic selection, agronomic traits, migration.
Introduction Since their domestication, sheep (Ovis aries) have been providing meat, wool, skin, milk, and other products to humans. They are essential for welfare of hundreds of millions of people [...]