Widespread interest in the first successful Out of Africa dispersal of modern humans ∼60-80 thousand years ago via a southern migration route has overshadowed the study of later periods of South Arabian prehistory. In this work, we show that the post-Last Glacial Maximum period of the past 20,000 years, during which climatic conditions were becoming more hospitable, has been a significant time in the formation of the extant genetic composition and population structure of this region. This conclusion is supported by the internal diversification displayed in the highly resolved phylogenetic tree of 89 whole mitochondrial genomes (71 being newly presented here) for haplogroup R0a-the most frequent and widespread haplogroup in Arabia. Additionally, two geographically specific clades (R0a1a1a and R0a2f1) have been identified in non-Arabic speaking peoples such as the Soqotri and Mahri living in the southern part of the Arabian Peninsula where a past refugium was identified by independent archaeological studies. Estimates of time to the most recent common ancestor of these lineages match the earliest archaeological evidence for seafaring activity in the peninsula in the sixth millennium BC.
- MeSH
- demografie MeSH
- fylogeneze MeSH
- haplotypy MeSH
- lidé MeSH
- mitochondriální DNA genetika MeSH
- molekulární evoluce MeSH
- podnebí MeSH
- populační genetika MeSH
- sekvenční analýza DNA MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, U.S. Gov't, Non-P.H.S. MeSH
- Geografické názvy
- Afrika MeSH
In the present study, we have investigated the polymorphism of the mitochondrial microsatellite, situated between 303 and 315 bp positions, in a Tunisian population. The haplotype frequencies of this microsatellite were compared to those of other populations (Berbers from Sejnene and Takrouna, Bedouins, Portuguese, Italians, French, British, Spanish and Turkish). The obtained results reveal this mitochondrial microsatellite as a frequent hot spot of mononucleotide insertions. In fact, his polymorphic rate is superior to 93% in all analysed populations. The results showed that the two haplotypes 309.1 315.1 and 315.1 are the most frequent in all studied populations. The haplotype corresponding to the Cambridge Reference Sequence (CRS) is only detected in the Tunisian population, the Berbers from Sejnene and the British people.
- MeSH
- interpretace statistických dat MeSH
- lidé MeSH
- mitochondriální DNA analýza diagnostické užití genetika MeSH
- polymorfismus genetický genetika MeSH
- Check Tag
- lidé MeSH
- Geografické názvy
- Tunisko MeSH
To shed light on the study of the genetic structure of an isolated Berber community – Takrouna, seven polymorphic Alu insertions (ACE, APO-A1, F13B, TPA-25, PV92, B65 and D1) have been studied in a sample of 33 Berbers. The results show that genetic diversity, measured by heterozygosity, is relatively high in this community. It varied from 0.1896 concerning ACE to 0.4981 for TPAA-25. All loci are polymorphic. Thus, despite its small size, its antiquity and the endogamy realised, one would await a derived effect which reduces, even eliminates this diversity. However, it is not the case. Moreover, to better understand the genetic structure of this population, a multidimensional scaling analysis (MDS) and an AMOVA have been effected with other populations from the world. Results present that in spite of the isolation of Takrouna, this later conserved a North-African structure.
