Mitochondrial DNA polymorphisms in the Amerindian: Tarahumara, Huichol, and Purépecha, and in one Mestizo Mexican population. L. SANDOVAL-RAMÍREZ1,2, M.T. MAGAÑA-TORRES1,2, M. CASAS-CASTAÑEDA2, J.M. OLIVA-ORTIZ1,2, G. VACA1,2, F. RIVAS1,2, J.M. CANTÚ2. 1) División de Genética, CIBO, IMSS, Guadalajara, MÉXICO; 2) Doctorado en Genética Humana, CUCS Universidad de Guadalajara, Guadalajara, MÉXICO.
OBJETIVE: To describe and compare mtDNA haplotypes among Mexican populations: Mestizo of the West, Tarahumara, Huichol and Purépecha. METHODS: mtDNA of 200 unrelated individuals was analyzed; 50 Mestizos from Western Mexico and 150 native of the three American ethnic groups: 50 Southeastern of Chihuahua Tarahumaras, 50 North of Jalisco and East of Nayarit Huicholes and 50 lake region of Michoacan state Purépechas. Twenty-one polymorphic sites were analyzed using the PCR-RFLP technique. First, the haplogroups A, B, C, D and M were identified. The samples that the origin of their mitocondrial haplotype could not be identified, 12 additional polymorphic sites and the sequenciation of the HVI region were analyzed with the purpose to assign them to some of the following haplogroups: X (European-American); H, I, J, K and U (European), L (African) and F (Asian). RESULTS: In 200 samples, 15 different haplotypes were identified by the analysis of nine ethnic-specific polymorphic sites. This allowed the assignation of the haplogroups A, B, C and D in 188 samples. The distribution in the mestizo population was: A(34%),B(24%),C(10%),D(10%)and A/B (4%),in Tarahumara: A(12%),B(30%),C(54%) and D(2%),in Huichol: A(46%),B(26%),C(26%)and D(0%)and in Purépecha: A(44%),B(24%),C(18%),D(0%),A/D(6%)and C/D(6%). Twelve samples did not pertained to the haplogroups A,B,C and D(nine Mestizos, one Tarahumara, one Huichol and one Purépecha). Eight Mestizos were assigned to European haplogroups H, K and U. Haplogroup X was not observed among these four populations, and a high number of compound haplotypes (12%) was present in the Purépecha population. CONCLUSIONS: mtDNA was of Amerindian origin in its majority (82% Mestizos and 98% Tarahumaras, Huicholes and Purépechas). The genes flow of European origin that conform the cluster of Mexican pool genes came through males. There was no evidence of maternal African component in this population sample.