mtDNA affinities of the peoples of north-central Mexico

mtDNA haplotypes of representatives of the cosmopolitan peoples of north-ce ntral Mexico were studied. Two hundred twenty-three samples from individual s residing in vicinities of two localities in north-central Mexico were ana lyzed. A combination of strategies was employed to identify the origin of e ach haplotype, including length variation analysis of the COII and tRNA(LYS ) intergenic region, nucleotide sequence analysis of control region hyperva riable segment 1, and RFLP analysis of PCR products spanning diagnostic sit es. Analysis of these data revealed that the majority of the mtDNA haplotyp es were of Native American origin, belonging to one of four primary Native American haplogroups. Others were of European or African origin, and the fr equency of African haplotypes was equivalent to that of haplotypes of Europ ean derivation. These results provide diagnostic, discrete character, molec ular genetic evidence that, together with results of previous studies of cl assical genetic systems, is informative with regard to both the magnitude o f African admixture and the relative maternal contribution of African, Euro pean, and Native American peoples to the genetic heritage of Mexico. Phylog enetic analysis revealed that African sequences formed a basal, paraphyleti c group.