HLA genes in Mexican Mazatecans, the peopling of the Americas and the uniqueness of Amerindians

The HLA allele frequency distribution of the Mexican Mazatecan Indians (Olm ec culture) has been studied and compared with those of other First America n Natives and worldwide populations (3 total of 12,100 chromosomes; 6,050 i ndividuals from 59 different populations). The main conclusions are: 1) An indirect evidence of Olmec and Mayan relatedness is suggested, further supp orting the notion that Olmecs may have been the precursors of Mayans; 2) La nguage and genetics do not completely correlate in microenvironmental studi es; and 3) Peopling of the Americas was probably more complex than postulat ed by Greenberg and others (three peopling waves). Significant genetic inpu t from outside is not noticed in Meso and South American Amerindians accord ing to the phylogenetic analyses; while all world populations (including Af ricans, Europeans, Asians, Australians, Polynesians, North American Na-Dene Indians and Eskimos) are genetically related. Meso and South American Amer indians tend to remain isolated in the Neighbor-Joining, correspondence and plane genetic distance analyses.