Novel KCNJ2 mutation in familial periodic paralysis with ventricular dysrhythmia.

Background: Mutations in the KCNJ2 gene, which codes cardiac and skeletal inward rectifying K+ channels (Kir2.1), produce Andersen's syndrome, which is characterized by periodic paralysis, cardiac arrhythmia, and dysmorphic features.

Methods And Results: In 3 Japanese family members with periodic paralysis, ventricular arrhythmias, and marked QT prolongation, polymerase chain reaction/single-strand conformation polymorphism/DNA sequencing identified a novel, heterozygous, missense mutation in KCNJ2, Thr192Ala (T192A), which was located in the putative cytoplasmic chain after the second transmembrane region M2.