Gene mutaion identification of a Chinese family with inherited Jervell and LangeNielsen syndrome

Objective To investigate the gene mutation in a Chinese family with inherited Jervel and LangeNielsen syndrome (JLNS) of the long QT syndrome (LQTS), in the hope to identify the specific JLNS mutation in Chinese. Method Polymerase chain reaction and DNA sequencing were used to screen for KCNQ1 and KCNE1 mutation. Results Novel heterozygous mutation G643S in the exon 15 of KCNQ1 was identified in proband and her sister, and the other mutation was found in their KCNQ1 exon 2a: 227th nucleotide C was replaced by T, which led to change of amino acid. Both asymptomatic parents each carried only one of the mutant alleles. Conclusions Novel compound heterozygous nonsense mutation of KCNQ1 can cause JLNS. Two new nonsense mutations were found in a Chinese LQTS patients with JLNS.