MTNR1B and type 2 diabetes mellitus: Although this is an elderly population in which no cross-sectional association was observed between the MTNR1B-rs10830963 polymorphism and fasting glucose at that moment, the increased type-2 diabetes risk may be due to this polymorphism producing the harmful effect on fasting glucose at a young age (not detectable in the elderly) and that over time, that dysfunction was increasing the risk of type-2 diabetes.