Association of HLA-DR with progressive systemic sclerosis in Japanese.

Objective. To clarify the contribution of HLA-DR genes to the susceptibility to progressive systemic sclerosis (PSS). Methods. HLA-DR typing was carried out in 36 Japanese patients with PSS, 42 with systemic lupus erythematosus and 104 healthy subjects by polymerase chain reaction (PCR) method using specific primers and by PCR-SSCP (single-standard DNA conformation polymorphism) method. Results. A haplotype DRB1 * 1502-DRB5 * 0102 was significantly increased in PSS (50.0%, p<0.00004, pc<0.001), especially in antitopoisomerase I antibody (a-Scl-70) positive patients (62.5%, p<0.000033, pc<0.001) and PSS with diffuse scleroderma (75.0%, p<0.000001, pc<0.0001)