An association between HLA DR1 and lichen planus

Abstract
Serological typing for HLA Class II antigens in 72 patients with lichen planus (LP) revealed a highly significant association with HLA DR1 and MT1 (DQw1). DR1 was present in 80% of patients with generalized LP, 54% with localized LP, 56% of patients with drug‐induced LP and in 31% of patients with mucosal LP, compared with 25% of normal controls. MT1 (DQw1) was found in 83% of the LP group and 62% of the normal controls. These findings strongly suggest a genetic predisposition or susceptibility to the development of generalized LP and perhaps also to drug‐induced LP.