HLA study in Mexico Nahua/Aztec Amerindians: Close relatedness to the ancient Central America ethnic groups.

Nahua population (also named Aztec or Mexica) was studied for HLA class II genes in a Mexican rural city (Santo Domingo Ocotitlan, Morelos State) belonging to the nowadays Náhuatl speaking areas in Mexico. The most frequent HLA class II alleles were typical Amerindian (HLA-DRB1*04:07, DQB1*03:01 DRB1*04:03 or DRB1*04:04) and also were some calculated extended haplotypes (HLA-DRB1*04:07-DQB1*03:02,DRB1*08:02-DQB1*04:02, or DRB1*10:01-DQB1*05:01 among others). When using HLA-DRB1 Neís genetic distances, our isolated Nahua population was found to be close to other Central America Amerindians like the ancient-established Mayans or Mixe. This may suggest that Nahuas origin was also from Central America. It contrasts to legend that assumes they came from the North, and they built the Aztec Empire after submitting Central America neighbouring ethnic groups before 1519 CE when Spaniards led by Hernán Cortés arrived to Mexico.

HLA genes in Amerindians from Mexico San Vicente Tancuayalab Teenek/Huastecos.

Huastecos or Teenek Amerindians are presently living at North East Mexico (San Luis Potosi State). They have probably one of the most ancient culture of Mexico and Central America together with Mayas and Olmec groups with which also show close relationships. Proximity to Atlantic Ocean/Mexican Gulf originated that Spaniards had very early contact with them at about 1519 CE or before. In the present paper we have aimed to study HLA gene profile which may be useful for HLA and disease epidemiology and transplant programs in Teeneks. HLA-DRB1*04:07, -DRB1*14:06 and -DRB1*04:11 have been found in high frequency like in other Amerindian groups. High frequency typical Amerindians HLA extended haplotypes have been found, such as A*02-B*35-DRB1*04:07-DQB1*03:02; A*68-B*39-DRB1*04:07-DQB1*03:02 and A*02-B*39-DRB1*04:07-DQB1*03:02; also new haplotypes have been described, like A*02-B*52-DRB1*04:11-DQB1*03:02, A*68-B*35-DRB1*14:02-DQB1*03:01 and A*68-B*40-DRB1*16:02-DQB1*03:01. Genetic proximity is observed not only to linguistically close Mayans, but also to Mazatecans, Mixtecans and Zapotecans, who speak an altogether different languages; it shows once more that genes and languages do not correlate. This population was greatly diminished after European contact between 1500 and 1600 years CE; in fact, North and South America First Inhabitants population was brought from 80 down to 8 million people because of diseases (i.e.: measles, smallpox or influenza), slavery and war.