对山地大猩猩的全基因组测序揭示了一个数量不断减少的种群和同系繁殖会如何影响这些大猩猩的基因多元性及如何对其生存造成影响;现在的估计认为，全世界山地大猩猩数目不超过800只。作为一个濒危大型类人猿亚种，山地大猩猩是全球性的动物保护标志，然而，研究人员对其基因组多元性所知甚少。为了对其做进一步的研究，Yali Xue及同事对采自13只东部大猩猩(7只为中部非洲维龙加地区的山地大猩猩，6只为东部低地大猩猩)的血样本进行了测序。在将这些大猩猩的基因组与所有4个大猩猩亚种的基因组(包括那些西部低地大猩猩种群的基因组)进行比较之后，研究人员发现，在东部大猩猩亚种(山地大猩猩和东部低地大猩猩)中的基因多元性要少得多，尤其是那些对免疫系统功能重要的基因多元性。此外，基于他们的结果，研究人员得出结论，这些山地大猩猩与其他东部大猩猩亚种至少在基因上部分隔离，并且其基因变异率极端低下，后者可能反映了同系繁殖。在通常情况下，同系繁殖会增加来自疾病和环境变化的威胁，但Xue等人显示，对山地大猩猩而言，同系繁殖还引起了有问题基因突变的消除。这种现象可能代表了在一个持续萎缩种群中的为生存而出现的适应性改变。作者们说，他们所观察到的基因多样性低下似乎在2万多年前就已经开始(这大约和东部与西部大猩猩亚种间停止交配的时间相同)，它也许与气候改变和人类活动有关。这些发现给未来的保护和研究提供了一个基因组资源。

    Mountain gorilla genomes reveal the impact of long-term population decline and inbreeding

    Mountain gorillas are an endangered great ape subspecies and a prominent focus for conservation, yet we know little about their genomic diversity and evolutionary past. We sequenced whole genomes from multiple wild individuals and compared the genomes of all four Gorilla subspecies. We found that the two eastern subspecies have experienced a prolonged population decline over the past 100,000 years, resulting in very low genetic diversity and an increased overall burden of deleterious variation. A further recent decline in themountain gorilla population has led to extensive inbreeding, such that individuals are typically homozygous at 34% of their sequence, leading to the purging of severely deleterious recessive mutations from the population. We discuss the causes of their decline and the consequences for their future survival.