African-derived south American populations: A history of symmetrical and asymmetrical matings according to sex revealed by bi- and uni-parental genetic markers

Estimates of African, European, and Amerindian contributions to the gene po ol of 11 predominantly African-derived South American populations were obta ined using five autosomal and one Y chromosome hypervariable loci, as well as mitochondrial DNA (sequences of the first hypervariable segment of the c ontrol region, plus two restriction sites and the presence or absence of th e CoII/tRNA(Lys) intergenic 9-bp deletion). The three latter characteristic s are reported here for the first time for 42 individuals living in three B razilian populations. Thirty-eight sequences were identified in these perso ns; 17 (45%) could be classified as being of African, 4 (11%) of Amerindian , and 2 (5%) of European origin. Evidence for asymmetrical matings in relat ion to sex and ethnic group was obtained for nine of the 11 populations. Th e most consistent finding was the introduction of European genes through ma les, but the results differ in the several communities, indicating the impo rtance of local factors in such interactions. (C) 1999 Wiley-Liss, Inc.