Common susceptibility and transmission pattern of human leukocyte antigen DRB1-DQB1 haplotypes to Korean and Caucasian patients with type 1 diabetes

The incidence of type 1 diabetes in Korea is less than 1/10th of that in th e United States, and it has been suggested that human leukocyte antigen (HL A) alleles of Asian patients associated with diabetes differ from those of Caucasians. In this study we analyzed the common susceptibility and transmi ssion pattern of a series of KLA DRB1-DQB1 haplotypes to Korean and Caucasi an patients with type 1 diabetes. We performed HLA DR and DQ typing of 158 type 1 diabetic patients in a case control study, 140 nondiabetic subjects from the same geographical area, 49 simplex families from Seoul, and 283 fa milies from the Human Biological Data Interchange. Although the haplotype f requencies in the two populations are quite different, when identical haplo types are compared, their odds ratios are nearly the same. For all parental haplotypes, the transmission to diabetic offspring was similar for Korean and Caucasian families (r = 0.8; P < 10(-4)). Allowing for ethnic differenc es in allelic associations due to different frequencies of DRB1 and DQB1 ha plotypes (linkage disequilibrium), these data show, not only by case-contro l comparison but also by transmission analyses of the haplotypes, that the susceptibility effects of DRB1-DQB1 haplotypes are consistent in Koreans an d Caucasians. Thus, the influence of class II susceptibility and resistance alleles appears to transcend ethnic and geographic diversity of type 1 dia betes.