Genome-Wide Selective Signatures Reveal Candidate Genes Associated with Hair Follicle Development and Wool Shedding in Sheep.

Zhihui Lei,Bohui Yang,Guoyan Qiao,Tingting Guo,Zengkui Lu,Mei Han,Weibo Sun,Chao Yuan,Hongchang Zhao,Jianye Li,Jianbin Liu,Liping Zhang,Shaohua Zhu,Yaojing Yue

doi:10.3390/genes12121924

Abstract

Hair follicle development and wool shedding in sheep are poorly understood. This study investigated the population structures and genetic differences between sheep with different wool types to identify candidate genes related to these traits. We used Illumina ovine SNP 50K chip genotyping data of 795 sheep populations comprising 27 breeds with two wool types, measuring the population differentiation index (Fst), nucleotide diversity (θπ ratio), and extended haplotype homozygosity among populations (XP-EHH) to detect the selective signatures of hair sheep and fine-wool sheep. The top 5% of the Fst and θπ ratio values, and values of XP-EHH < −2 were considered strongly selected SNP sites. Annotation showed that the PRX, SOX18, TGM3, and TCF3 genes related to hair follicle development and wool shedding were strongly selected. Our results indicated that these methods identified important genes related to hair follicle formation, epidermal differentiation, and hair follicle stem cell development, and provide a meaningful reference for further study on the molecular mechanisms of economically important traits in sheep.

Highlights

Hair sheep is a kind of sheep with wool shedding that can adapt to a variety of climatic conditions and ecological environment
Due to the obvious depilation characters and high anti-parasite [2], hair sheep are becoming popular in the United States and other temperate regions, such as the Dorper, Wiltshire Horn, Katahdin sheep, and Barbados Black belly
The Illumina ovine SNP 50K chip genotyping data for the 27 breeds used in the study were obtained from the International Sheep Genomics Consortium (ISGC), National Animal Genome Research Program (NRSP), a Web-Interfaced generation Database dedicated to genetic Diversity Exploration (WIDDE), and the Ontario Sheep Farmers (OSF)

Summary

Introduction

Hair sheep is a kind of sheep with wool shedding that can adapt to a variety of climatic conditions and ecological environment. Hair sheep have coats with few woolly fibers or fibers that are shed annually Do they not have to shear their wool often, but they are more resistant to parasites and diseases. The Dorper sheep is a heavy muscled sheep breed that originated in South Africa It is a result of the breeding between Dorset Horn rams with Blackhead Persian ewes [3]. The White Dorper is as its name implies a pure white-haired sheep and the traditional Dorper has a white body and black head much lie the Blackhead Persian breed. They are one of the most popular breeds of sheep in the United States today due to their shedding characteristics and superior conformation. It would be of interest to explore the genetic mechanisms of wool shedding using selective signatures to identify genes related to sheep hair follicle development and the control of wool shedding and to understand their functions

Methods

Results

Conclusion