Cookies on this website
We use cookies to ensure that we give you the best experience on our website. If you click 'Continue' we'll assume that you are happy to receive all cookies and you won't see this message again. Click 'Find out more' for information on how to change your cookie settings.

OBJECTIVE - A major feature of type 1 diabetes is the appearance of islet autoantibodies before diagnosis. However, although the genetics of type 1 diabetes is advanced, the genetics of islet autoantibodies needs further investigation. The primary susceptibility loci in type 1 diabetes, the HLA class I and II genes, are believed to determine the specificity and magnitude of the autoimmune response to islet antigens. We investigated the association of glutamic acid decarboxylase autoantibodies (GADA) and insulinoma-associated antigen-2 autoantibodies (IA-2A) with the HLA region. RESEARCH DESIGN AND METHODS - Associations of GADA and IA-2A with HLA-DRB1, HLA-DQB1, HLA-B, HLA-C, HLA-A, MICA, and 3,779 single nucleotide polymorphisms (SNPs) were analyzed in 2,531 childhood-onset case subjects (median time since diagnosis 5 years). All analyses were adjusted for age-at-diagnosis and duration of diabetes. RESULTS - GADA and IA-2A were associated with an older ageat- diagnosis (P < 10 -19). For GADA, the primary association was with HLA-DQB1 (P = 9.00 × 10 -18), with evidence of a second independent effect in the HLA class I region with SNP, rs9266722 (P = 2.84 3 1026). HLA-DRB1 had the strongest association with IA-2A (P = 1.94 × 10 -41), with HLA-A*24 adding to the association, albeit negatively (P = 1.21 × 10 -10). There was no evidence of association of either IA-2A or GADA with the highly type 1 diabetes predisposing genotype, HLA-DRB1*03/04. CONCLUSIONS - Despite genetic association of type 1 diabetes and the islet autoantibodies localizing to the same HLA class II genes, HLA-DRB1 and HLA-DQB1, the effects of the class II alleles and genotypes involved are quite different. Therefore, the presence of autoantibodies is unlikely to be causal, and their role in pathogenesis remains to be established. © 2011 by the American Diabetes Association.

Original publication

DOI

10.2337/db11-0131

Type

Journal article

Journal

Diabetes

Publication Date

01/10/2011

Volume

60

Pages

2635 - 2644