Patients in the GCK (n = 7) and HNF1A (n = 27) groups had similar age at onset (16.1 ± 7.8 vs 20.8 ± 9.0 years; p = 0.286), diabetes duration (9.88.8 vs 15.4 ± 10.1 years; p = 0.82) or BMI (20.6 ± 4.0 vs 23.3 ± 2.8; p = 0.143). This evidence concerns the gene GCK and diabetes mellitus.