Kuang Weimin, Hu Jingyang, Wu Hong, Fen Xiaotian, Dai Qingyan, Fu Qiaomei, Xiao Wen, Frantz Laurent, Roos Christian, Nadler Tilo, Irwin David M, Zhou Linchun, Yang Xu, Yu Li
State Key Laboratory for Conservation and Utilization of Bio-Resource in Yunnan, School of Life Sciences, Yunnan University, Kunming, China.
Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, IVPP, CAS, Beijing, China.
Front Genet. 2020 Dec 15;11:615926. doi: 10.3389/fgene.2020.615926. eCollection 2020.
The snub-nosed monkey genus () comprises five closely related species (, and ). All are among the world's rarest and most endangered primates. However, the genomic impact associated with their population decline remains unknown. We analyzed population genomic data of all five snub-nosed monkey species to assess their genetic diversity, inbreeding level, and genetic load. For , and , population size is positively correlated with genetic diversity and negatively correlated with levels of inbreeding. Other species, however, which possess small population sizes, such as and , show high levels of genetic diversity and low levels of genomic inbreeding. Similarly, in the three populations of , the Shennongjia population, which possesses the lowest population size, displays a higher level of genetic diversity and lower level of genomic inbreeding. These findings suggest that although and and the Shennongjia population might be at risk, it possess significant genetic diversity and could thus help strengthen their long-term survival potential. Intriguingly, with large population size possess high genetic diversity and low level of genetic load, but they show the highest recent inbreeding level compared with the other snub-nosed monkeys. This suggests that, despite its large population size, has likely been experiencing recent inbreeding, which has not yet affected its mutational load and fitness. Analyses of homozygous-derived deleterious mutations identified in all snub-nosed monkey species indicate that these mutations are affecting immune, especially in smaller population sizes, indicating that the long-term consequences of inbreeding may be resulting in an overall reduction of immune capability in the snub-nosed monkeys, which could provide a dramatic effect on their long-term survival prospects. Altogether, our study provides valuable information concerning the genomic impact of population decline of the snub-nosed monkeys. We revealed multiple counterintuitive and unexpected patterns of genetic diversity in small and large population, which will be essential for conservation management of these endangered species.
仰鼻猴属（）包括五个亲缘关系密切的物种（、和）。它们均属于世界上最珍稀、最濒危的灵长类动物。然而，与其种群数量下降相关的基因组影响仍不为人知。我们分析了所有五个仰鼻猴物种的种群基因组数据，以评估它们的遗传多样性、近亲繁殖水平和遗传负荷。对于、和，种群大小与遗传多样性呈正相关，与近亲繁殖水平呈负相关。然而，其他种群数量较小的物种，如和，却表现出高遗传多样性和低基因组近亲繁殖水平。同样，在的三个种群中，种群数量最少的神农架种群表现出较高的遗传多样性和较低的基因组近亲繁殖水平。这些发现表明，尽管和以及神农架种群可能面临风险，但它们拥有显著的遗传多样性，因此有助于增强其长期生存潜力。有趣的是，种群数量大的拥有高遗传多样性和低遗传负荷水平，但与其他仰鼻猴相比，它们显示出最近最高的近亲繁殖水平。这表明，尽管种群数量大，但可能最近一直在经历近亲繁殖，这尚未影响其突变负荷和适应性。对所有仰鼻猴物种中鉴定出的纯合衍生有害突变的分析表明，这些突变正在影响免疫系统，尤其是在种群数量较小的情况下，这表明近亲繁殖的长期后果可能导致仰鼻猴的免疫能力整体下降，这可能对它们的长期生存前景产生巨大影响。总之，我们的研究提供了有关仰鼻猴种群数量下降的基因组影响的宝贵信息。我们揭示了大小种群中遗传多样性的多种违反直觉和意想不到的模式，这对于这些濒危物种的保护管理至关重要。
