April 30, 2008

mtDNA correlated with facial height in Chad Basin

More studies like this ought to be done. While a causal link between mtDNA and craniofacial features seems unlikely, it is expected that in admixed populations of relatively recent origin there will be correlation between phenotypical attributes and mtDNA or Y chromosomes.

See also: mtDNA of Chad Basin populations, Inferring the population of origin of DNA evidence within the UK by allele-specific hybridization of Y-SNPs

Am J Hum Biol. 2008 Apr 28 [Epub ahead of print]

Mitochondrial DNA and craniofacial covariability of Chad Basin females indicate past population events.

Hájek M, Cerný V, Brůžek J.

The Chad Basin lies in the middle of the Sudanic African belt between the Sahara and the tropical rain forests. Its present-day settlement is a result of Holocene climatic changes and human immigrations from different parts of Africa. This study presents a statistical analysis of the relationships of physical features (stature and five main craniofacial measurements) and mitochondrial (mtDNA) haplogroup classifications in a sample of 282 adult individuals belonging to seven populations of different ethno-linguistic groups living in the Chad Basin. Drawing on the analysis of variance, we identified a female-specific DNA association between mtDNA haplogroup assignment and facial height. More specifically, the mtDNA haplogroups of East-African origin occur more frequently in females with relatively longer faces and, conversely, the mtDNA of West-African origin are found more frequently in females with lower faces. Interestingly, this kind of association is not found in the males of the same populations. Our interpretation refers mainly to population history; we suggest that facial height and mtDNA haplogroup co-variance in Chad Basin females reflects a long-term east-west population distribution in the past that made the facial differentiation possible.


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