Twenty single-nucleotide polymorphisms in four genes encoding cardiac ion channels.

We here report 20 novel single-nucleotide polymorphisms in four genes that are potentially involved in the excitement of cardiomyocytes: 1 in KCNA5 (encoding Kv1.5), 5 in KCNAB1 (encoding Kvbeta1.3), 5 in KCNIP2 (encoding KChIP2), and 9 in CACNA1C (encoding a cardiac L-type voltage-dependent calcium ion channel, dihydropyridine receptor). We also examined their allelic frequencies in Japanese individuals. These data will be useful for genetic association studies designed to investigate secondary long QT syndrome or other circulatory disorders.