基于全基因组填充重测序关联分析鉴别影响苏山猪初生体尺与乳头数性状的遗传位点

It aims to identify the genetic loci affecting the body size at birth and teat number traits of Sushan pigs, develop molecular markers that can be used for assisted breeding, and provide a theoretical basis for the continuous breeding of the growth and reproductive performance of Sushan pigs. In this experiment, the body size and teat number phenotypes of 269 Sushan piglets at birth (within 24 hours after birth) were measured, and ear tissue samples were collected. Based on whole-genome resequencing and genotype imputation strategies, the methods of genome-wide association study (GWAS) and fixation index (Fst) were used to mine the loci strongly associated with the target traits, and GO and KEGG analyses were carried out on the positional functional candidate genes to determine the most likely major genes. A total of 4 candidate loci were identified in this study, distributed on chromosomes 13, 14 and X. Among them, there were 2 loci significantly associated with the body size at birth traits and 2 loci significantly associated with the teat number traits. In this study, 1 candidate gene ACTA2 related to body length traits, 1 candidate gene COL4A6 related to chest circumference traits, and 3 candidate genes ACTA2, CRTAP and SEPTIN6 related to teat number traits were screened out, providing important molecular markers for the genetic improvement of the body size traits and teat number traits of Sushan pigs.

旨在鉴别影响苏山猪初生体尺和乳头数性状的遗传位点，开发可用于辅助育种的分子标记，为苏山猪生长和繁殖性能的持续选育提供理论基础。本试验对269头苏山猪初生仔猪（出生后24h内）的体尺和乳头数表型进行测定，并采集耳组织样品。基于全基因组重测序及基因型填充策略，利用全基因组关联分析（genome-wideassociationstudy, GWAS）和群体分化指数（fixationindex, Fst）的方法挖掘与目的性状强关联位点，并对位置功能候选基因开展GO和KEGG分析，确定最有可能的主效基因。本研究共鉴别到4个候选位点，分布在13、14和X染色体上，其中与初生体尺性状显著关联位点有2个，与乳头数性状显著关联位点有2个。本研究筛选出1个与体长性状相关的候选基因ACTA2；1个与胸围性状相关的候选基因COL4A6；3个与乳头数性状相关的候选基因ACTA2、CRTAP和SEPTIN6，为苏山猪体尺性状和乳头数性状的遗传改良提供了重要的分子标记。