GCK and diabetes mellitus: In the HNF1A–MODY group, ghrelin level significantly correlated with age at examination (ρ = −0.39, p = 0.008), diabetes duration (ρ = −0.30, p = 0.05), and was marginally correlated with BMI (ρ = −0.25, p = 0.1), whereas in GCK–MODY, there was a significant correlation with age (ρ = −0.41, p = 0.02).