Cerný V, Salas A, Hájek M, Zaloudková M, Brdicka R
Department of Anthropology and Environment, Institute of Archaeology, Czech Academy of Sciences, 118 01 Prague 1, Czech Republic.
Ann Hum Genet. 2007 Jul;71(Pt 4):433-52. doi: 10.1111/j.1469-1809.2006.00339.x. Epub 2007 Jan 18.
The Chad Basin was sparsely inhabited during the Stone Age, and its continual settlement began with the Holocene. The role played by Lake Chad in the history and migration patterns of Africa is still unclear. We studied the mitochondrial DNA (mtDNA) variability in 448 individuals from 12 ethnically and/or economically (agricultural/pastoral) different populations from Cameroon, Chad, Niger and Nigeria. The data indicate the importance of this region as a corridor connecting East and West Africa; however, this bidirectional flow of people in the Sahel-Sudan Belt did not erase features peculiar to the original Chad Basin populations. A new sub-clade, L3f2, is described, which together with L3e5 is most probably autochthonous in the Chad Basin. The phylogeography of these two sub-haplogroups seems to indicate prehistoric expansion events in the Chad Basin around 28,950 and 11,400 Y.B.P., respectively. The distribution of L3f2 is virtually restricted to the Chad Basin alone, and in particular to Chadic speaking populations, while L3e5 shows evidence for diffusion into North Africa at about 7,100 Y.B.P. The absence of L3f2 and L3e5 in African-Americans, and the limited number of L-haplotypes shared between the Chad Basin populations and African-Americans, indicate the low contribution of the Chad region to the Atlantic slave trade.
乍得盆地在石器时代人口稀少，其持续有人居住始于全新世。乍得湖在非洲历史和迁徙模式中所起的作用仍不明确。我们研究了来自喀麦隆、乍得、尼日尔和尼日利亚12个种族和/或经济（农业/游牧）不同群体的448个人的线粒体DNA（mtDNA）变异性。数据表明该地区作为连接东非和西非的走廊的重要性；然而，萨赫勒 - 苏丹地带的这种双向人口流动并未消除乍得盆地原始居民特有的特征。描述了一个新的亚分支L3f2，它与L3e5一起很可能是乍得盆地的本土分支。这两个亚单倍群的系统地理学似乎分别表明了在约28,950年和11,400年前的全新世晚期乍得盆地的史前扩张事件。L3f2的分布实际上仅局限于乍得盆地，特别是讲乍得语的人群，而L3e5显示出在约7,100年前扩散到北非的证据。非裔美国人中不存在L3f2和L3e5，且乍得盆地人群与非裔美国人之间共享的L单倍型数量有限，这表明乍得地区对大西洋奴隶贸易的贡献较低。
