When studying the genetic structure of human populations, the role of cultural factors may be difficult to ascertain due to a lack of formal models. Linguistic diversity is a typical example of such a situation. Patrilocality, on the other hand, can be integrated into a biological framework, allowing the formulation of explicit working hypotheses. The present study is based on the assumption that patrilocal traditions make the hypervariable region I of the mtDNA a valuable tool for the exploration of migratory dynamics, offering the opportunity to explore the relationships between genetic and linguistic diversity. We studied 85 Niger-Congo-speaking patrilocal populations that cover regions from Senegal to Central African Republic. A total of 4175 individuals were included in the study.
By combining a multivariate analysis aimed at investigating the population genetic structure, with a Bayesian approach used to test models and extent of migration, we were able to detect a stepping-stone migration model as the best descriptor of gene flow across the region, with the main discontinuities corresponding to forested areas.
Our analyses highlight an aspect of the influence of habitat variation on human genetic diversity that has yet to be understood. Rather than depending simply on geographic linear distances, patterns of female genetic variation vary substantially between savannah and rainforest environments. Our findings may be explained by the effects of recent gene flow constrained by environmental factors, which superimposes on a background shaped by pre-agricultural peopling.
Statistical analysis of HVS-I (mtDNA) in Niger-Congo populations
Not sure that the paper has much interest but it affects a region with not too many studies and is open access so a brief mention may be appropriate.
Valeria Montano et al. The influence of habitats on female mobility in Central and Western Africa inferred from human mitochondrial variation. BMC Evolutionary Biology 2013. Open access → LINK [doi:10.1186/1471-2148-13-24]
One of the problems I find to their approach is the use of only the deprecated HVS-I (control region) of the mtDNA, along with absolutely no list of inferred haplogroups (not even in the supplemental materials apparently). Based on just HVS-I data, then they proceed to make statistical analysis of all sorts, which may have some interest but is not my cup of tea, really. Maybe someone else may find use for this stuff however.