GCK and type 2 diabetes mellitus: Additionally, two patients initially diagnosed as T2D were found to carry missense variants: a likely pathogenic variant, c.613G>T (p.Asp205Tyr) in the GCK gene (MODY2) and pathogenic variant, c.4135C>T (p.Arg1379Cys) in the ABCC8 gene (MODY12), respectively.