HLA GENE AND HAPLOTYPE FREQUENCIES IN THE NORTH-AMERICAN POPULATION -THE NATIONAL MARROW DONOR PROGRAM DONOR REGISTRY

Background. As of May 1, 1995, the National Marrow Donor Program had a donor registry consisting of over 1.35 million HLA-typed volunteers r ecruited from most major cities and states in the United States. This registry represents the largest single HLA-typed pool of normal indivi duals in the world, Methods. We analyzed the HLA-A, -B, -DR locus phen otypes of the National Marrow Donor Program donors in order to estimat e gene and haplotype frequencies for major racial groups of the United States: Caucasian American, Asian American, African American, Latin A merican, and Native American. The large size of the database allowed u s to calculate the frequencies of relatively rare antigens and haploty pes with more accuracy than previous studies, Results. We observed 89, 522 distinguishable HLA-A, -B phenotypes in 1,351,260 HLA-A, -B-typed donors and 302,867 distinguishable HLA-A, -B, -DR phenotypes in 406,50 3 HLA-A, -B, -DR-typed donors. Gene and haplotype frequencies differed remarkably among the five racial groups, with African Americans and A sian Americans having a large number of haplotypes that were specific to their racial groups, whereas Caucasian Americans, Latin Americans, and Native Americans shared a number of common haplotypes. Conclusions . These data represent an important resource for investigators in the fields of transplantation and population genetics. The gene and haplot ype frequencies can be used to aid clinicians in advising patients abo ut the probability of finding a match within a specific ethnic group, or to determine donor recruitment goals and strategies, The informatio n is also a valuable resource for individuals who are interested in po pulation genetics, selection and evolution of polymorphic human genes, and HLA-disease association.