Mutations of KCNJ2 gene associated with Andersen-Tawil syndrome in Korean families.

Mutations of the KCNJ2 gene are a major underlying cause of Andersen-Tawil syndrome (ATS), a rare autosomal dominant inherited disorder that is characterized by periodic paralysis, cardiac arrhythmias, and developmental dysmorphic features. The KCNJ2 gene encodes an inward rectifying K(+) channel protein, Kir2.1, which plays an important role in maintaining the homeostasis of channel current in various cell types. We have identified two missense mutations of KCNJ2 (R218Q and M307I) in two Korean families diagnosed with ATS. The M307I mutation is a novel mutation, located at the intracellular C-terminal domain, which is known to be concerned with putative phosphatidylinositol 4,5-bisphosphate (PIP(2)) binding and channel trafficking.