A de novo missense mutation (R1623Q) of the SCN5A gene in a Japanese girl with sporadic long QT syndrome

✍ Scribed by Hiroyuki Yamagishi; Michiko Furutani; Mitsuhiro Kamisago; Yoshiyuki Morikawa; Yoshifumi Kojima; Yoshiaki Hino; Yoshiyuki Furutani; Misa Kimura; Shin-ichiro Imamura; Atsuyoshi Takao; Kazuo Momma; Rumiko Matsuoka

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 50 KB
• Volume: 11
• Category: Article
• ISSN: 1059-7794
• DOI: 10.1002/(sici)1098-1004(1998)11:6<481::aid-humu12>3.0.co;2-q

✦ Synopsis

Two missense mutations and a nine-nucleotide deletion of the cardiac sodium channel (SCN5A) gene have been shown to cause long QT syndrome (LQTS) in sev eral familial cases. We identified a novel missense mutation (R1623Q) of the SCN5A gene in a Japanese girl with sporadic LQTS. We used polymerase chain r eaction, single-strand conformation polymorphism analysis and DNA sequence a nalysis to identify a mutation of the SCN5A gene in the patient. A single nu cleotide substitution of guanine to adenine, in codon 1623, changed the codi ng sense of the SCN5A from arginine to glutamine (R1623Q) in the S4 segment of domain IV which is a highly conserved region of the SCN5A. This mutation was not identified in the unaffected biological parents and brother of the p atient, and 100 normal, unrelated individuals. This finding is the first evi dence of a de novo mutation in SCN5A associated with LQTS.