HLA CLASS-II IMMUNOGENETICS OF IDDM IN YEMENITE JEWS

The association between HLA-DR and DQ and insulin dependent diabetes m ellitus (IDDM) mas analyzed in 47 patients and 76 controls of Yemenite Jewish origin. The IDDM susceptibility alleles DRB103011, DQA1*0501, DQB102 and DRB1*0402, DQA1*0301, DQB1*0302 found in Caucasians had a very strong predisposing effect also in the Yemenite IDDM group. The DRB107, DQA1*0201 and DQB1*02 alleles were found to have a strong neg ative association with IDDM. None of the patients carried DRB107 and DQA10201 compared with healthy controls (43.7%). Our analysis reveale d that the DRB103011 DQA1*0501 DQB1*02/DRB1*4 DQA1*03 DQB1*0302 heter ozygous genotype confers the highest susceptibility (59.6% in patients vs. 0% in controls). The homozygous DRB103 and DRB1*04 genotypes wer e also found to be positively associated with the disease. 81% of the patients compared to 1.3% of controls carried the susceptibility allel es on both haplotypes. In conclusion, the development of IDDM in Yemen ite Jews is strongly dependent on the presence of the susceptibility H LA alleles and on the absence of the DRB107 haplotype. The Yemenite J ewish group is uniquely homogenous with regard to genetic susceptibili ty factors involved in the process of IDDM, and may thus be an ideal m odel for further genetic studies. (C) American Society for Histocompat ibility and Immunogenetics, 1998. Published by Elsevier Science Inc.