de Knijff P, Kayser M, Caglià A, Corach D, Fretwell N, Gehrig C, Graziosi G, Heidorn F, Herrmann S, Herzog B, Hidding M, Honda K, Jobling M, Krawczak M, Leim K, Meuser S, Meyer E, Oesterreich W, Pandya A, Parson W, Penacino G, Perez-Lezaun A, Piccinini A, Prinz M, Roewer L
MGC-Department of Human Genetics, Leiden University, The Netherlands.
Int J Legal Med. 1997;110(3):134-49. doi: 10.1007/s004140050052.
By means of a multicenter study, a large number of males have been characterized for Y-chromosome specific short tandem repeats (STRs) or microsatellites. A complete summary of the allele frequency distributions for these Y-STRs is presented in the Appendix. This manuscript describes in more detail some of the population genetic and evolutionary aspects for a restricted set of seven chromosome Y STRs in a selected number of population samples. For all the chromosome Y STRs markedly different region-specific allele frequency distributions were observed, also when closely related populations were compared. Haplotype analyses using AMOVA showed that when four different European male groups (Germans, Dutch, Swiss, Italians) were compared, less than 10% of the total genetic variability was due to differences between these populations. Nevertheless, these pairwise comparisons revealed significant differences between most population pairs. Assuming a step-wise mutation model and a mutation frequency of 0.21%, it was estimated that chromosome Y STR-based evolutionary lines of descent can be reliably inferred over a time-span of only 1950 generations (or about 49,000 years). This reduces the reliability of the inference of population affinities to a historical, rather than evolutionary time scale. This is best illustrated by the construction of a human evolutionary tree based on chromosome Y STRs in which most of the branches connect in a markedly different way compared with trees based on classical protein polymorphisms and/or mtDNA sequence variation. Thus, the chromosome Y STRs seem to be very useful in comparing closely related populations which cannot probably be separated by e.g. autosomal STRs. However, in order to be used in an evolutionary context they need to be combined with more stable Y-polymorphisms e.g. base-substitutions.
通过一项多中心研究，大量男性已被鉴定出Y染色体特异性短串联重复序列（STRs）或微卫星。这些Y-STRs的等位基因频率分布的完整总结见附录。本手稿更详细地描述了在选定数量的人群样本中，一组受限的七个Y染色体STRs的一些群体遗传学和进化方面。对于所有Y染色体STRs，即使比较密切相关的群体，也观察到明显不同的区域特异性等位基因频率分布。使用分子变异分析（AMOVA）的单倍型分析表明，当比较四个不同的欧洲男性群体（德国人、荷兰人、瑞士人、意大利人）时，总遗传变异中不到10%是由于这些群体之间的差异。然而，这些成对比较揭示了大多数群体对之间的显著差异。假设逐步突变模型和突变频率为0.21%，据估计，基于Y染色体STRs的进化世系只能在仅1950代（或约49000年）的时间跨度内可靠推断。这将群体亲缘关系推断的可靠性降低到历史而非进化时间尺度。基于Y染色体STRs构建的人类进化树能最好地说明这一点，其中大多数分支的连接方式与基于经典蛋白质多态性和/或线粒体DNA序列变异构建的树明显不同。因此，Y染色体STRs在比较可能无法通过常染色体STRs等区分的密切相关群体时似乎非常有用。然而，为了在进化背景下使用，它们需要与更稳定的Y多态性（如碱基替换）相结合。
