HL-A Antigens as Markers for Disease Susceptibility and Autoimmunity in Graves' Disease

Abstract
Evidence for genetic control of susceptibility to Graves disease was sought using the human major histocompatibility (HL-A) antigens as genetic markers. HL-A typing and assays for antithyroglobulin (anti-Tg) and anti-(thyroid)-microsomal (anti-M) autoantibodies were performed on 62 unrelated Caucasian patients with Graves' disease and 113 normal unrelated Caucasian controls. The frequency of the HL-A8 antigen in the patient population was increased to 47% compared to 21% in controls (p < 0.0009) and 0% in a previously reported group of patients with post irradiation Graves' disease. The findings demonstrate that the HL-A antigens may be useful genetic markers of disease susceptibility and, in fact, may represent markers of different pathogenetic processes. It is proposed that histocompatibility linked immune response genes may provide a common explanation for the reported associations observed between thyroidal disease susceptibility and the species major histocompatibility locus in both the present human study and in previous murine studies.