Several loci influencing traits like fasting plasma glucose (FPG), fasting insulin, 2h glucose and HbA1c were identified and many of them like ADCY5, PROX1, GCK, GCKR, and DGKB-TMEM195 also influenced risk of T2D (Dupuis et al., 2010; Soranzo et al., 2010; Strawbridge et al., 2010; Manning et al., 2012; Scott et al., 2012). Here, GCK is linked to type 2 diabetes mellitus.