Importance of HLA-DRB1 and DQA1 genes and of the amino acid polymorphisms in the functional domain of DR beta 1 chain in multiple sclerosis.

The association of some HLA class II alleles with multiple sclerosis (MS) has been amply documented. In the present study the role of HLA class II haplotypes and genotypes and of polymorphic amino acids at the DR beta 1 locus, located in the antigen binding groove and the CD4 binding domain of the DR beta 1 chain, were studied in 78 unrelated Caucasian chronic progressive MS (CP MS) patients and 204 controls. The results confirmed the positive association of the DRB1*1501 allele and through linkage also of the DRB1*1501-DQA1*0102 haplotype with MS.

Increased and decreased relative risk for non-insulin-dependent diabetes mellitus conferred by HLA class II and by CD4 alleles.

Non-insulin-dependent diabetes mellitus has been recognized to be heterogeneous in etiology, with multiple subgroups. Several genes or chromosomal regions have been implicated in the development of the disease. In this study the association of HLA class II alleles and genotypes and the association of CD4 and CD3 polymorphisms were assessed in a large number of Belgian non-insulin-dependent diabetes mellitus patients.

Possible association of CD3 and CD4 polymorphisms with insulin-dependent diabetes mellitus (IDDM).

Population and family studies show that predisposition to type I diabetes (IDDM) is multifactorial, and that polymorphisms in the MHC region contribute substantially to the susceptibility to IDDM. In the present study the association of polymorphisms in the CD4 and the delta subunit of CD3 with IDDM were examined in a Belgian population. We observed that the frequency of the CD A4/A4 genotype and of the CD3 91 allele were significantly increased P = 0.