Yan Jibing, Song Chunmei, Liang Jiaqi, La Yanni, Lai Jiandong, Pan Ruliang, Huang Zhipang, Li Baoguo, Zhang Pei
Shaanxi Key Laboratory of Animal Conservation, College of Life Sciences, Northwest University, Xi'an 710069, China.
Baima Snow Mountain National Nature Reserve Administrative Bureau, Diqing 674500, China.
Animals (Basel). 2024 Aug 5;14(15):2276. doi: 10.3390/ani14152276.
Genetic diversity is an essential indicator that echoes the natural selection and environmental adaptation of a species. Isolated small populations are vulnerable to genetic drift, inbreeding, and limited gene flow; thus, assessing their genetic diversity is critical in conservation. In this study, we studied the genetic diversity of black-and-white snub-nosed monkeys () using neutral microsatellites and five adaptive major histocompatibility complex (MHC) genes. Two alleles, two alleles, two alleles, two alleles, and three alleles were isolated from a population. The results indicate that neutral microsatellites demonstrate a high degree of heterozygosity and polymorphism, while adaptive MHC genes display a high degree of heterozygosity and moderate polymorphism. The results also show that balancing selection has prominently influenced the MHC diversity of the species during evolution: (1) significant positive selection is identified at several amino acid sites (primarily at and near antigen-binding sites) of the , , and genes; (2) phylogenetic analyses display the patterns of trans-species evolution for all MHC loci. This study provides valuable genetic diversity insights into black-and-white snub-nosed monkeys, which dwell at the highest altitude and have experienced the harshest environmental selection of all primates globally since the Pleistocene. Such results provide valuable scientific evidence and a reference for making or amending conservation strategies for this endangered primate species.
遗传多样性是反映一个物种自然选择和环境适应的重要指标。孤立的小种群易受遗传漂变、近亲繁殖和有限基因流的影响；因此，评估它们的遗传多样性对保护工作至关重要。在本研究中，我们使用中性微卫星和五个适应性主要组织相容性复合体（MHC）基因研究了黑白仰鼻猴（ ）的遗传多样性。从一个种群中分离出两个 等位基因、两个 等位基因、两个 等位基因、两个 等位基因和三个 等位基因。结果表明，中性微卫星表现出高度的杂合性和多态性，而适应性MHC基因表现出高度的杂合性和中等程度的多态性。结果还表明，平衡选择在进化过程中对该物种的MHC多样性产生了显著影响：（1）在 、 和 基因的几个氨基酸位点（主要是抗原结合位点及其附近）发现了显著的正选择；（2）系统发育分析显示了所有MHC位点的跨物种进化模式。本研究为黑白仰鼻猴提供了有价值的遗传多样性见解，黑白仰鼻猴栖息在最高海拔地区，自更新世以来经历了全球所有灵长类动物中最严酷的环境选择。这些结果为制定或修订这种濒危灵长类物种的保护策略提供了有价值的科学证据和参考。
