KCNJ11 and neonatal diabetes mellitus: However, three genetic alterations are more frequent in NDM cases: abnormalities of the 6q24 locus methylation, and activating variants in the ABCC8 and KCNJ11 genes, which encode the SUR1 and Kir6.2 subunits, respectively, of the ATP-dependent potassium channel (KATP channel) (10).