Frequencies of HLA-A2 alleles in five U.S. population groups. Predominance Of A*02011 and identification of HLA-A*0231.

Direct DNA sequencing was used to determine the frequency of alleles within the HLA-A2 family in five US population groups. The most frequently detected HLA-A2 allele in all groups was HLA-A*02011. Caucasian and Native American populations appear to be the most homogeneous exhibiting 95.7% and 94.3% A*02011, respectively. Hispanic and Asian/Pacific Islander populations were the most allelicly diverse populations with 9 and 7 different HLA-A2 alleles present, respectively, but the majority of the populations were HLA-A*02011. African-Americans were also diverse, not in the number of alleles seen, but in the percentage of non-A*02011 alleles in the population. HLA-A*0202 (25.8%) and A*0205 (12.9%) were present in a large percentage of African-Americans. Only 13 of the 31 known HLA-A2 alleles were observed in the study. The allelic distributions reflected statistically significant differences among population groups.