Common variants at ten loci modulate the QT interval duration in the QTSCD Study. Nat Genet. 2009;41:407-414. [PMID: 19305409 DOI: 10.1038/ng.362]

A genome-wide association scan of RR and QT interval duration in 3 European genetically isolated populations: the EUROSPAN project

BACKGROUND

We set out to identify common genetic determinants of the length of the RR and QT intervals in 2325 individuals from isolated European populations.

METHODS AND RESULTS

We analyzed the heart rate at rest, measured as the RR interval, and the length of the corrected QT interval for association with 318 237 single-nucleotide polymorphisms. The RR interval was associated with common variants within GPR133, a G-protein-coupled receptor (rs885389, P=3.9 x 10(-8)). The QT interval was associated with the earlier reported NOS1AP gene (rs2880058, P=2.00 x 10(-10)) and with a region on chromosome 13 (rs2478333, P=4.34 x 10(-8)), which is 100 kb from the closest known transcript LOC730174 and has previously not been associated with the length of the QT interval.

CONCLUSIONS

Our results suggested an association between the RR interval and GPR133 and confirmed an association between the QT interval and NOS1AP.

Genetics of cardiac repolarization

Prolongation of the electrocardiographic QT interval, a measure of cardiac repolarization, is associated with arrhythmogenic disorders and is a risk factor for sudden cardiac death. Two genome-wide association studies (GWAS) of variation in the QT interval in population-based cohorts now report association with variants in a subset of ion channel genes and other new associations.

Common variants at ten loci influence QT interval duration in the QTGEN Study

QT interval duration, reflecting myocardial repolarization on the electrocardiogram, is a heritable risk factor for sudden cardiac death and drug-induced arrhythmias. We conducted a meta-analysis of three genome-wide association studies in 13,685 individuals of European ancestry from the Framingham Heart Study, the Rotterdam Study and the Cardiovascular Health Study, as part of the QTGEN consortium. We observed associations at P < 5 x 10(-8) with variants in NOS1AP, KCNQ1, KCNE1, KCNH2 and SCN5A, known to be involved in myocardial repolarization and mendelian long-QT syndromes. Associations were found at five newly identified loci, including 16q21 near NDRG4 and GINS3, 6q22 near PLN, 1p36 near RNF207, 16p13 near LITAF and 17q12 near LIG3 and RFFL. Collectively, the 14 independent variants at these 10 loci explain 5.4-6.5% of the variation in QT interval. These results, together with an accompanying paper, offer insights into myocardial repolarization and suggest candidate genes that could predispose to sudden cardiac death and drug-induced arrhythmias.