KCNJ11 and neonatal diabetes mellitus: Since Kir6.2 is expressed in skeletal muscle, peripheral nerves, and the brain (Hattersley and Ashcroft 2005), specific KCNJ11 variants are associated with developmental delay and epilepsy, collectively known as developmental delay, epilepsy, and NDM (DEND) syndrome (Flanagan et al. 2006).