Evaluation of ethnogeographic structuring of uniparental lineages in Zimbabwean populations

As for most African countries, Zimbabwe is underrepresented in human genetic studies, with little information available on the uniparental lineages' composition of its populations. Therefore, with the aim of investigating the maternal and paternal inheritance of Zimbabwe, 479 samples from the most representative ethnolinguistic groups were analyzed in this study, using mtDNA and Y-chromosomal specific markers. Population substructure was investigated by mean of F_ST genetic distances and AMOVA, after grouping the samples based on Guthrie's Bantu Zone Classification and geography. Based on the results, it was possible to conclude that the Zimbabwean populations do not maintain a high stratification, except for the Kalanga group that shows evidence of ethnic and geographic isolation. To further investigate the composition of Zimbabwean male lineages, Y-STR haplotypes were used to predict the haplogroups of all samples using the NEVGEN software. A total of 64 samples below the prediction confidence threshold, as well as 73 random samples above it, were typed for Y-SNPs. For samples below the confidence threshold, there was a coincidence between the NEVGEN and Y-SNP results in only 67 % of cases. For samples with predicted haplogroups above the confidence threshold, Y-SNP genotyping showed two misclassifications. This result demonstrates that Y-SNP typing is still essential for defining haplogroups in populations that are underrepresented in genetic studies.