HLA-DR typing in identical twins with insulin-dependent diabetes: difference between concordant and discordant pairs.
A total of 106 pairs of identical twins, of whom 56 were concordant and 50 discordant for insulin-dependent diabetes, were typed for HLA-DR. In both the concordant and discordant groups there was a high prevalence of the antigens DR3 and DR4, a low prevalence of DR5 and DR7, and a virtual absence of DR2. The heterozygous phenotype DR3,DR4 was more prevalent in concordant than discordant pairs. This was therefore the first demonstration of a genetic difference between concordant and discordant identical twin pairs. These findings suggest that possession of both DR3 and DR4 antigens confers a greater genetic predisposition to insulin-dependent diabetes than does the possession of either antigen alone.
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D002648:Child; D002675:Child, Preschool; D003920:Diabetes Mellitus / Q000235:genetics / Q000276:immunology*; D004200:Diseases in Twins; D005260:Female; D005802:Genes, MHC Class II; D006684:HLA-DR Antigens; D015803:HLA-DR3 Antigen; D015804:HLA-DR4 Antigen; D000949:Histocompatibility Antigens Class II / Q000032:analysis*; D006801:Humans; D008875:Middle Aged; D010641:Phenotype; D011247:Pregnancy; D014427:Twins; D014430:Twins, Monozygotic
D006684:HLA-DR Antigens; D015803:HLA-DR3 Antigen; D015804:HLA-DR4 Antigen; D000949:Histocompatibility Antigens Class II