Institute of Swine Science, Nanjing Agricultural University, Nanjing 210095, China.
Key Laboratory in Nanjing for Evaluation and Utilization of Livestock and Poultry (Pigs) Resources, Ministry of Agriculture and Rural Areas, Nanjing Agricultural University, Nanjing 210095, China.
Genes (Basel). 2022 Jul 22;13(8):1294. doi: 10.3390/genes13081294.
Vulvar size and angle are meaningful traits in pig production. Sows with abnormal vulva generally show reproductive disorders. In order to excavate candidate loci and genes associated with pig's vulvar traits, 270 Suhuai pigs with vulvar phenotype were genotyped by a porcine single nucleotide polymorphisms (SNP) Chip. Then, Chip data were imputed using resequenced data of 30 Suhuai pigs as a reference panel. Next, we estimated the heritability and performed a genome-wide association study (GWAS) for vulvar traits. The heritabilities for the traits vulvar length (VL), vulvar width (VW) and vulvar angle (VA) in this pig population were 0.23, 0.32 and 0.22, respectively. GWAS based on Chip data identified nine significant SNPs on the chromosomes (SSC) 2, 7, 9 and 13 for VL or VW. GWAS based on imputed data identified 11 new quantitative trait loci (QTL) on SSC1, 2, 7, 8, 9, 11, 13, 16 and 17 for VL or VW. The most significant QTL for VL on SSC2 were refined to a 3.48-3.97 Mb region using linkage disequilibrium and linkage analysis (LDLA). In this refined region, and , involved in the development of the reproductive tract, cell growth and vulvar cancer, could be new candidate genes affecting VL. Our results provided potential genetic markers for the breeding of vulvar traits in pigs and deepened the understanding of the genetic mechanism of vulvar traits.
外阴大小和角度是猪生产中的有意义特征。外阴异常的母猪通常表现出生殖障碍。为了挖掘与猪外阴特征相关的候选基因座和基因，我们对 270 头具有外阴表型的苏淮猪进行了基因分型，使用了猪单核苷酸多态性（SNP）芯片。然后，我们使用 30 头苏淮猪的重测序数据作为参考面板对芯片数据进行了 imputation。接下来，我们估计了外阴特征的遗传力，并进行了全基因组关联研究（GWAS）。在这个猪群体中，外阴长度（VL）、外阴宽度（VW）和外阴角度（VA）的遗传力分别为 0.23、0.32 和 0.22。基于芯片数据的 GWAS 鉴定了 2、7、9 和 13 号染色体（SSC）上与 VL 或 VW 相关的 9 个显著 SNP。基于 imputed 数据的 GWAS 鉴定了 11 个与 VL 或 VW 相关的新的数量性状基因座（QTL），位于 SSC1、2、7、8、9、11、13、16 和 17 号染色体上。在 SSC2 上与 VL 相关的最显著 QTL 通过连锁不平衡和连锁分析（LDLA）被精细定位到 3.48-3.97 Mb 区域。在这个精细定位区域中，和 ，参与生殖道发育、细胞生长和外阴癌，可能是影响 VL 的新候选基因。我们的研究结果为猪外阴特征的选育提供了潜在的遗传标记，并加深了对外阴特征遗传机制的理解。
