HLA-DR3 in dermatitis herpetiformis.

Twenty-one patients with dermatitis herpetiformis were typed for HLA-ABC and -DR determinants. The incidence of HLA-AI, -B8 and -DR3 antigens was found to be significantly higher (P: = 10(-3), less than 10(-6) and less than 10(-6), respectively) among patients with dermatitis herpetiformis than among the normal population. HLA-DR3 was found in 85.7% of patients, HLA-B8 in 66.7% and HLA-AI in 61.9% only. These results indicate that HLA-DR3 is the antigen primarily associated in dermatitis herpetiformis and the latter antigens (HLA-AI and -B8) are present in increased incidence, probably due to the known linkage disequilibrium of these antigens with HLA-DR3.