ANTIBODIES TO GAD IN JAPANESE DIABETIC-PATIENTS - A MULTICENTER STUDY

We determined the prevalence of antibodies to glutamic acid decarboxyl ase (anti-GAD) in Japanese diabetic patients, Anti-GAD were detected b y RIP Anti-GAD Hoechst, which is a new sensitive radioimmunoassay (RIA ) kit using purified pig brain GAD as the antigen. One thousand nine h undred Japanese patients were collected by the Study Group for Antibod ies to GAD. The prevalence of anti-GAD in the subjects of this study w as: 35.4% (326/921) in all patients with IDDM, 50.3% (96/191) in patie nts with IDDM less than 1-year duration, 4.3% (29/680) in NIDDM, 37.9% (39/103) in slowly progressive IDDM, 10.5% (4/38) in gestational diab etes mellitus, 0% (0/27) in impaired glucose tolerance, 4.8% (6/124) i n the school children with glycosuria, 2.1% (1/47) in the relatives of IDDM and 5.0% (1/20) in neurological diseases without diabetes. The p revalence in normal subjects was 2.2% (7/323). Anti-GAD are frequently detected by the RIA kit in patients with IDDM of short duration and t his assay may be useful for population screening for IDDM and for bett er understanding of its pathogenesis.