Barbieri Chiara, Vicente Mário, Oliveira Sandra, Bostoen Koen, Rocha Jorge, Stoneking Mark, Pakendorf Brigitte
Department of Evolutionary Genetics, MPI for Evolutionary Anthropology, Leipzig, Germany; Department of Biological, Geological and Environmental Sciences, Laboratory of Molecular Anthropology, University of Bologna, Bologna, Italy.
CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos da Universidade do Porto, Vairão, Portugal; STAB VIDA, Investigação e Serviços em Ciências Biológicas, Lda, Oeiras, Portugal.
PLoS One. 2014 Jun 5;9(6):e99117. doi: 10.1371/journal.pone.0099117. eCollection 2014.
Bantu speech communities expanded over large parts of sub-Saharan Africa within the last 4000-5000 years, reaching different parts of southern Africa 1200-2000 years ago. The Bantu languages subdivide in several major branches, with languages belonging to the Eastern and Western Bantu branches spreading over large parts of Central, Eastern, and Southern Africa. There is still debate whether this linguistic divide is correlated with a genetic distinction between Eastern and Western Bantu speakers. During their expansion, Bantu speakers would have come into contact with diverse local populations, such as the Khoisan hunter-gatherers and pastoralists of southern Africa, with whom they may have intermarried. In this study, we analyze complete mtDNA genome sequences from over 900 Bantu-speaking individuals from Angola, Zambia, Namibia, and Botswana to investigate the demographic processes at play during the last stages of the Bantu expansion. Our results show that most of these Bantu-speaking populations are genetically very homogenous, with no genetic division between speakers of Eastern and Western Bantu languages. Most of the mtDNA diversity in our dataset is due to different degrees of admixture with autochthonous populations. Only the pastoralist Himba and Herero stand out due to high frequencies of particular L3f and L3d lineages; the latter are also found in the neighboring Damara, who speak a Khoisan language and were foragers and small-stock herders. In contrast, the close cultural and linguistic relatives of the Herero and Himba, the Kuvale, are genetically similar to other Bantu-speakers. Nevertheless, as demonstrated by resampling tests, the genetic divergence of Herero, Himba, and Kuvale is compatible with a common shared ancestry with high levels of drift, while the similarity of the Herero, Himba, and Damara probably reflects admixture, as also suggested by linguistic analyses.
班图语族群在过去4000至5000年间扩展到撒哈拉以南非洲的大部分地区，于1200至2000年前抵达南部非洲的不同地区。班图语分为几个主要分支，属于东部和西部班图语分支的语言分布在中非、东非和南非的大部分地区。关于这种语言划分是否与东部和西部班图语使用者之间的基因差异相关，目前仍存在争议。在扩张过程中，班图语使用者会与当地的不同人群接触，比如南部非洲的科伊桑狩猎采集者和牧民，他们之间可能有通婚现象。在本研究中，我们分析了来自安哥拉、赞比亚、纳米比亚和博茨瓦纳的900多名说班图语个体的完整线粒体DNA基因组序列，以调查班图语扩张最后阶段所涉及的人口过程。我们的结果表明，这些说班图语的人群在基因上大多非常同质化，东部和西部班图语使用者之间没有基因划分。我们数据集中的大部分线粒体DNA多样性是由于与当地人群不同程度的混合。只有牧民希姆巴族和赫雷罗族因特定L3f和L3d谱系的高频率而突出；后者在讲科伊桑语、以狩猎和小规模畜牧为生的邻近达马拉族中也有发现。相比之下，赫雷罗族和希姆巴族在文化和语言上的近亲库瓦勒族，在基因上与其他说班图语的人相似。然而，重抽样测试表明，赫雷罗族、希姆巴族和库瓦勒族的基因差异与具有高度漂变的共同祖先相符，而赫雷罗族、希姆巴族和达马拉族的相似性可能反映了混合现象，语言分析也表明了这一点。
