PDF(Pubmed)
Abstract：
Hu sheep (HS), a breed of sheep carrying the FecB mutation gene, is known for its \"year-round estrus and multiple births\" and is an ideal model for studying the high fecundity mechanisms of livestock. Through analyzing and comparing the genomic selection features of Hu sheep and other sheep breeds, we identified a series of candidate genes that may play a role in Hu sheep\'s high fecundity mechanisms. In this study, we conducted whole-genome resequencing on six breeds and screened key mutations significantly correlated with high reproductive traits in sheep. Notably, the CC2D1B gene was selected by the fixation index (FST) and the cross-population composite likelihood ratio (XP-CLR) methods in HS and other five breeds. It was worth noting that the CC2D1B gene in HS was different from that in other sheep breeds, and seven missense mutations have been identified. Furthermore, the linkage disequilibrium (LD) analysis revealed a strong linkage disequilibrium in this specific gene region. Subsequently, by performing different grouping based on FecB genotypes in Hu sheep, genome-wide selective signal analysis screened several genes related to reproduction, such as BMPR1B and PPM1K. Besides, FST analysis identified functional genes related to reproductive traits, including RHEB, HSPA2, PPP1CC, HVCN1, and CCDC63. Additionally, a missense mutation was found in the CCDC63 gene and the haplotype was different between the high reproduction (HR) group and low reproduction (LR) group in HS. In summary, we discovered genetic differentiation among six distinct breeding sheep breeds at the whole genome level. Additionally, we identified a set of genes which were associated with reproductive performance in Hu sheep and visualized how these genes differed in different breeds. These findings laid a theoretical foundation for understanding genetic mechanisms behind high prolific traits in sheep.
摘要：
湖羊（HS），一种带有FecB突变基因的绵羊，以其“全年发情期和多胎”而闻名，是研究牲畜高繁殖力机制的理想模型。通过分析和比较湖羊和其他绵羊品种的基因组选择特征，我们确定了一系列可能在湖羊高繁殖力机制中起作用的候选基因。在这项研究中,我们对6个绵羊品种进行了全基因组重测序，筛选出与高繁殖性状显著相关的关键突变。值得注意的是,在HS和其他5个品种中,通过固定指数(FST)和交叉群体复合似然比(XP-CLR)方法选择CC2D1B基因.值得注意的是，HS中的CC2D1B基因与其他绵羊品种不同，并鉴定出7个错义突变.此外，连锁不平衡（LD）分析显示该特定基因区域存在强烈的连锁不平衡。随后，通过对湖羊的FecB基因型进行不同的分组，全基因组选择性信号分析筛选了几个与繁殖相关的基因，例如BMPR1B和PPM1K。此外,FST分析确定了与生殖性状相关的功能基因，包括RHEB,HSPA2,PPP1CC,HVCN1和CCDC63。此外,在CCDC63基因中发现了一个错义突变，HS的高繁殖（HR）组和低繁殖（LR）组的单倍型不同。总之,我们在全基因组水平上发现了六个不同种绵羊的遗传分化。此外,我们确定了一组与湖羊繁殖性能相关的基因，并观察了这些基因在不同品种中的差异。这些发现为理解绵羊高产量性状背后的遗传机制奠定了理论基础。
