In a sensitivity analysis restricted to those individuals with complete relevant data (n = 10,893), the HR for incident diabetes in those positive for GAD65 antibodies compared with those individuals who were negative was 2.22 (95% CI 1.49, 3.31) without adjustment and 2.13 (95% CI 1.46, 3.11) with adjustment for a five HLA haplotype risk score. This evidence concerns the gene GAD2 and diabetes mellitus.