ABCC8 encodes a high affinity sulphonylurea receptor SUR1 that is coupled to the Kir6.2 subunit, which is encoded by KCNJ11. Both genes are part of the ATP-sensitive  potassium channel, which plays a key role in regulating the release of hormones such as insulin and glucagon in the beta cell.  Mutations in either gene can affect the potassium channel’s activity and insulin secretion, ultimately leading to the development of T2D.  Interestingly, ABCC8 and KCNJ11 are only 4.5 kb apart, and not far from the INS gene. Variant forms of KCNJ11 (Lys) and ABCC9 (Ala) genes have been associated with T2D, as well as other diabetes-related traits.  Because of the close proximity of these genes, current studies are evaluating whether they work in concert with each other, or rather have an independent effect on T2D susceptibility.