EVOLUTIONARY AND ANTHROPOLOGICAL IMPLICATIONS OF MITOCHONDRIAL-DNA VARIATION IN AFRICAN BRAZILIAN POPULATIONS

The genetic diversity in three African Brazilian populations was analy zed using the 360-nucleotide sequences of the first hypervariable segm ent (HVS-I) of the mitochondrial DNA control region, Results from 42 i ndividuals revealed 39 distinct lineages defined by 54 variable positi ons. Some of the sequence types were clearly African derived, but appa rent Amerindian lineages also occurred. The lineage clusters did not s how any association with place of residence of the individuals or with their morphological classification. Nucleotide diversity, however, se emed to be associated with degree of admixture. The mismatch distribut ion suggests a major human population expansion 60,000 years ago.