Baldan Sergelen, Sölkner Johann, Gebre Kahsa Tadel, Mészáros Gábor, Crooijmans Richard, Periasamy Kathiravan, Pichler Rudolf, Manaljav Bayarjargal, Baatar Narantuya, Purevdorj Myagmarsuren
Department for Animal Science, Mongolian University of Life Sciences, Ulaanbaatar, Mongolia.
Department of Sustainable Agricultural Systems, University of Natural Resources and Life Sciences, Vienna, Vienna, Austria.
Front Genet. 2024 Sep 17;15:1421529. doi: 10.3389/fgene.2024.1421529. eCollection 2024.
Characterization studies of the phenotypic and genetic diversity of Mongolian goats are limited, despite several goat breeds being registered in the country. This study aimed to evaluate the phenotypic and genetic diversity of 14 cashmere goat populations in Mongolia, consisting largely of identified goat breeds.
Body weight, cashmere quality, and coat color were the phenotypic traits considered in this study. A linear model was used to fit body weight and cashmere traits, and least squares means () were estimated for the region and location classes. Genetic diversity and structure were assessed using a goat 50K SNP array.
The studied populations exhibited greater phenotypic diversity at the regional level. A very small overall differentiation index (: 0.017) was revealed by Wright's and a very small overall inbreeding index ( :0.019) was revealed based on runs of homozygosity. Genetic clustering of populations by principal components showed large variances for the two goat populations of the Russian admixture (Gobi Gurvan Saikhan and Uuliin Bor), and smaller but differentiated clusters for the remaining populations. Similar results were observed in the admixture analysis, which identified populations with the highest (Govi Gurvan Saikhan and Uuliin Bor) and lowest (Tsagaan Ovoo Khar) exotic admixtures. A genomewide association study (GWAS) of body weight and cashmere traits identified a few significant variants on chromosomes 2, 4, 5, 9, and 15, with the strongest variant for cashmere yield on chromosome 4. The GWAS on coat color yielded nine significant variants, with the strongest variants located on chromosomes 6, 13, and 18 and potential associations with , , and genes. These signals were also found in other studies on coat color and patterns in goats.
Mongolian cashmere goats showed relatively low genetic differentiation and low inbreeding levels, possibly caused by the traditional pastoral livestock management system and the practice of trading breeding bucks across provinces, along with a recent increase in the goat population. Further investigation of cashmere traits using larger samples and alternative methods may help identify the genes or genomic regions underlying cashmere quality in goats.
尽管蒙古国已登记了多个山羊品种，但对蒙古山羊的表型和遗传多样性的特征研究仍然有限。本研究旨在评估蒙古国14个绒山羊群体的表型和遗传多样性，这些群体主要由已鉴定的山羊品种组成。
本研究考虑的表型性状包括体重、羊绒品质和毛色。使用线性模型拟合体重和羊绒性状，并估计区域和地点类别的最小二乘均值（ ）。使用山羊50K SNP芯片评估遗传多样性和结构。
研究群体在区域水平上表现出更大的表型多样性。赖特氏 揭示的总体分化指数非常小（ ：0.017），基于纯合子连续片段揭示的总体近亲繁殖指数也非常小（ ：0.019）。主成分分析对群体进行的遗传聚类显示，俄罗斯混合血统的两个山羊群体（戈壁古尔班赛汗和乌利因布尔）差异很大，其余群体的聚类较小但有差异。在混合分析中也观察到了类似结果，该分析确定了外来混合比例最高（戈壁古尔班赛汗和乌利因布尔）和最低（察干奥沃哈尔）的群体。体重和羊绒性状的全基因组关联研究（GWAS）在2号、4号、5号、9号和15号染色体上鉴定出了一些显著变异，4号染色体上与羊绒产量相关的变异最强。毛色的GWAS产生了9个显著变异，最强的变异位于6号、13号和18号染色体上，并且与 、 和 基因存在潜在关联。这些信号在其他关于山羊毛色和图案的研究中也有发现。
蒙古绒山羊显示出相对较低的遗传分化和近亲繁殖水平，这可能是由于传统的游牧畜牧业管理系统、跨省份交易种公羊的做法以及近期山羊数量的增加所致。使用更大样本和替代方法对羊绒性状进行进一步研究，可能有助于识别山羊羊绒品质背后的基因或基因组区域。
