Analysis of the distribution of HLA-A alleles in populations from five continents.

The variation and frequency of HLA-A genotypes were established by PCR-SSOP typing in diverse geographically distributed populations: Brazilian, Colombian Kogui, Cuban, Mexican, Omani, Singapore Chinese, and South African Zulu. HLA-A allelic families with only one allele were identified for HLA-A01, -A23, -A25, -A31, -A32, -A36, -A43, -A69, -A80; and with two alleles for HLA-A03, -A11, -A26, -A29, -A33, -A34, and -A66. Greater variation was detected for HLA-A02, -A24, and -A*68 allele families. Colombian Kogui and Mexican Seris showed the least diversity with respect to HLA-A alleles, albeit with small numbers tested, with only four and five HLA-A alleles identified, respectively. It would appear by their presence in all populations studied, either rural or indigenous, that certain alleles are very important in pathogen peptide presentation.