The serotype is determined by the antibody recognition of α36 subset of HLA-A α-chains.

A36 is more common in Africa (North and East) and Central Asia.

A36 is rare HLA-A allele group.

Outside Africa, more than half of the populations have no A36 and the majority that do, have only trace levels.

HLA DR3-DQ2 linkage and frequency indicates a strong possibility of a recent migration from either North or West Africa in which the DR3-DQ2 (notably DRB1*0302) and A*33-B*58 haplotypes were carried into and redistributed from Central Asia into the surrounding populations.