HLA-DR2-associated DRB1 and DRB5 alleles and haplotypes in Koreans

There are considerable racial differences in the distribution of HLA-DR2-as sociated DRB1 and DRB5 alleles and the characteristics of linkage disequili brium between these alleles. In this study, the frequencies of DR2-associat ed DRB1 and DRB5 alleles and related haplotypes were analyzed in 186 DR2-po sitive individuals out of 800 normal Koreans registered for unrelated bone marrow donors. HLA class I antigen typing was performed by the serological method and DRB1 and DRB5 genotyping by the PCR-single strand conformational polymorphism method. Only 3 alleles were detected for DR2-associated DRB1 and DRB5 genes, respectively: DRB1*1501 (gene frequency 8.0%), *1502 (3.2%) , *1602 (0.9%); DRB5*0101 (8.0%), *0102 (3.2%), and *0202 (0.9%). DRB1-DRB5 haplotype analysis showed an exclusive association between these alleles: DRB1*1501-DRB5*0101 (haplotype frequency 8.0%), DRB1*1502-DRB5*0102 (3.2%), and DRB1*1602-DRB5*0202 (0.9%). The 5 most common DR2-associated A-B-DRB1 haplotypes occurring at frequencies of greater than or equal to0.5% were A2 4-B52-DRB1*1502 (1.8%), A2-B62-DRB1*1501, A2-B54-DRB1*1501, A26-B61-DRB1*15 01, and A24-B51-DRB1*1501, The remarkable homogeneity in the haplotypic ass ociations between DR2-associated DRB1 and DRB5 alleles in Koreans would be advantageous for organ transplantation compared with other ethnic groups sh owing considerable heterogeneity in the distribution of DRB1-DRB5 haplotype s. Human Immunology 61, 937-941 (2000). (C) American Society for Histocompa tibility and Immunogenetics, 2000. Published by Elsevier Science Inc.