Koop B F, Goodman M, Xu P, Chan K, Slightom J L
Nature. 1986;319(6050):234-8. doi: 10.1038/319234a0.
Molecular studies indicate that chimpanzee and gorilla are the closest relatives of man (refs 1-7 and refs therein). The small molecular distances found point to late ancestral separations, with the most recent being between chimpanzee and man, as judged by DNA hybridization. Kluge and Schwartz contest these conclusions: morphological characters group a chimpanzee-gorilla clade with the Asian ape orang-utan in Kluge's cladistic study and with an orang-utan-human clade in Schwartz's study. Clearly, extensive sequencing of nuclear DNA is needed to resolve by cladistic analysis the branching order within Hominoidea. Towards this goal, we are sequencing orthologues of the primate psi eta-globin locus. Here, we compare the newly completed sequences of orang-utan and rhesus monkey with human, chimpanzee, gorilla, owl monkey, lemur and goat orthologues. Our findings substantially increase the evidence indicative of a human-chimpanzee-gorilla clade with ancestral separations around 8 to 6 Myr ago. We also verify that neutral hominoid DNA evolved at markedly retarded rates.
分子研究表明，黑猩猩和大猩猩是人类最亲近的亲属（参考文献1 - 7及其中引用文献）。通过DNA杂交判断，所发现的小分子距离表明祖先的分化时间较晚，其中最近的分化发生在黑猩猩和人类之间。克鲁格（Kluge）和施瓦茨（Schwartz）对这些结论提出质疑：在克鲁格的分支系统学研究中，形态特征将黑猩猩 - 大猩猩进化枝与亚洲猩猩归为一类；而在施瓦茨的研究中，则将其与猩猩 - 人类进化枝归为一类。显然，需要对核DNA进行广泛测序，以便通过分支系统分析来确定人猿总科内的分支顺序。为实现这一目标，我们正在对灵长类ψη - 珠蛋白基因座的直系同源基因进行测序。在此，我们将新完成测序的猩猩和恒河猴序列与人类、黑猩猩、大猩猩、夜猴、狐猴和山羊的直系同源基因进行比较。我们的研究结果大大增加了表明人类 - 黑猩猩 - 大猩猩进化枝在约800万至600万年前发生祖先分化的证据。我们还证实，中性人猿DNA的进化速率明显减缓。
