The most frequent chromosomal aneuploidy in humans, trisomy 21 (T21), has only been reported twice in the common chimpanzee (Pan troglodytes). In both cases, phenotypical traits were comparable to human T21 traits and were formally diagnosed through conventional techniques like chromosomal staining. Here, we present the first application of sequencing data as a diagnostic tool to compare chromosomal dosage imbalances in chimpanzees. By calculating the ratio of mapped reads on each chromosome between a case and a control, we observe a trisomic dosage imbalance on chromosome 21 in the case individual. While case numbers remain too low to be conclusive, evidence suggests that prevalence of T21 in chimpanzees could be lower than in humans. In future genetic testing of captive ape populations, the genetic diagnostic methods presented here will allow for a reliable and time-efficient assessment of the global prevalence of chromosomal dose imbalances in chimpanzees and other great apes.

中文翻译：

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黑猩猩（Pan troglodytes）21三体的遗传诊断

人类中最常见的染色体非整倍性，即 21 三体 (T21)，在普通黑猩猩 (Pan troglodytes) 中仅报告过两次。在这两种情况下，表型特征与人类 T21 特征相当，并通过染色体染色等常规技术进行正式诊断。在这里，我们首次将测序数据用作比较黑猩猩染色体剂量失衡的诊断工具。通过计算病例和对照之间每条染色体上映射读数的比率，我们观察到病例个体 21 号染色体上的三体剂量不平衡。虽然病例数仍然太低而无法得出结论，但有证据表明黑猩猩中 T21 的流行率可能低于人类。在未来对圈养类人猿种群的基因检测中，