Novel de novo mutation in the KCNJ2 gene in a patient with Andersen-Tawil syndrome.
Andersen-Tawil syndrome is a rare autosomal-dominant disease characterized by episodic muscle weakness, cardiac arrhythmias, and dysmorphic features. Mutations in the KCNJ2 gene (which encodes an inward-rectifying potassium channel protein, Kir2.1) have been reported to be responsible for this disorder. Reported here is a novel de novo mutation in the KCNJ2 gene in a patient with Andersen-Tawil syndrome. This mutation predicts the substitution of alanine for glycine at position 146 (Gly146Ala, c.437G > C) of Kir2.1 and is located at the extracellular pore loop region that serves as a principal ion-selective filter. The patient did not respond to acetazolamide, but experienced an improvement of the paralytic symptoms on treatment with a combination of spironolactone, amiloride, and potassium supplements.
Kim
June-Bum
JB
Department of Pediatrics, College of Medicine, Konyang University, 685 Gasoowon-dong, Su-goo, Daejun; Choongnam 302-718, South Korea. hoppdoctor@hanmail.net
Chung
Ki-Wha
KW
D000293:Adolescent; D000595:Amino Acid Sequence; D050030:Andersen Syndrome / Q000188:drug therapy / Q000235:genetics*; D001483:Base Sequence; D004252:DNA Mutational Analysis; D006801:Humans; D008297:Male; D020125:Mutation, Missense; D017354:Point Mutation; D024661:Potassium Channels, Inwardly Rectifying / Q000235:genetics*; D017386:Sequence Homology, Amino Acid; D016896:Treatment Outcome
C489457:KCNJ2 protein, human; D024661:Potassium Channels, Inwardly Rectifying