HLA in the Azores Archipelago: possible presence of Mongoloid genes

Abstract

The HLA profile of the Azoreans has been compared with those of other world populations in order to provide additional information regarding the history of their origins. The allele frequencies, genetic distances between populations, correspondence analyses and most frequent haplotypes were calculated. Our results indicate that the Azorean population most likely contains an admixture of high‐frequency Caucasoid, Mongoloid and, to a lesser degree, Negroid HLA genes. The middle Atlantic Azores Archipelago was officially colonized by the Portuguese after 1439 and historical records are concordant with the existence of Caucasoid and Negroid population. However, Mongoloid genes were not suspected, but the Oriental HLA haplotypes A24‐B44‐DR6‐DQ1, A29‐B21‐DR7‐DQ2 and A2‐B50‐DR7‐DQ2 are the fourth, fifth and sixth most frequent ones in Azores. A correspondence analysis shows that the Azorean population is equidistant from Asian and European populations and genetic distances are in some cases closer to the Asian than to European ethnic groups, and never are significantly different; also, B*2707 subtype is found in Asians and Azoreans (but not in Europeans) and the same Machado‐Joseph Disease founder haplotypes (Chr 14) are found in both Japanese and Azoreans. It is proposed that a Mongoloid population exists in Azores; whether, the arrival occurred prior to discovery is undetermined.