The HLA antigens of two Negrito populations in the Philippines.

HLA antigens were determined for the A, B and C loci among 86 Aetas of west-central Luzon and 87 Mamanwas of north-eastern Mindanao, Philippines. The overall antigenic profiles of these two groups were essentially similar to those of other Asian-Pacific populations with some peculiarities in common with Papua New Guineans. However, the results of heterogeneity tests and the comparison of statistically significant phenotypic associations showed a highly significant difference between the Aeta and the Mamanwa groups. It was postulated that the two “Negrito” groups represent different migrations to the Philippines.