Human mitochondrial DNA variation and the origin of Basques

作者：Jaume Bertranpetit, J Sala, Francesc Calafell, P. A. Underhill, Pedro Moral, David Comas · 发表于：Annals of Human Genetics · 年份：1995 · DOI：10.1111/j.1469-1809.1995.tb01606.x · 被引用次数：204 · 研究领域：Forensic and Genetic Research、Forensic Anthropology and Bioarchaeology Studies、Genetic diversity and population structure

The hypervariable segment I of the control region of the mtDNA (positions 16024-16383) was PCR-amplified from mouth scrape and hairs and sequenced in 45 unrelated individuals of pure matrilineal Basque descent. Twenty-seven different sequences were found, of which 21 are unique to the Basques. The allelic partition observed, together with resampling experiments, suggested that much more variation remained to be discovered. The mean pairwise difference in number of nucleotides between individuals was 3-15, a very low value. Moreover, the number of steps for the most parsimonious tree is very low compared to the number of different sequences. Both findings suggest that the Basque population was founded by a few lineages that diverged in a short time span. The number of nucleotide differences between individuals was shown not to be influenced by the distance between their birthplaces, thus validating the sampling strategy used a posteriori. The pairwise difference distribution agreed well with the three-parameter model proposed by Rogers & Harpending (1992). The parameter estimates found for the Basques implied that a demographic expansion (or perhaps two, given the bimodal shape of the distribution) took place sometime between 14500 and 42000 BP which is in agreement with archaeological data. Our sample was compared to other populations for which D-loop sequences were available through the Nei & Miller (1990) distance. In a neighbour-joining tree, all the Caucasoid samples, inc...