Identification and functional characterization of the human ether-a-go-go-related gene Q738X mutant associated with hereditary long QT syndrome type 2.

QT interval prolongation, a risk factor for arrhythmias, may be associated with genetic variants in genes governing cardiac repolarization. Long QT syndrome type 2 (LQT2) is caused by mutations in the human ether-a-go‑go-related gene (hERG). This gene encodes a voltage-gated potassium channel comprised of 4 subunits, and the formation of functional channels requires the proper assembly of these 4 subunits.

Blockage of hERG current and the disruption of trafficking as induced by roxithromycin.

Roxithromycin is an oral macrolide antibiotic agent that has been repeatedly reported to provoke excessive prolongation of the Q-T interval and torsades de pointes in clinical settings. To investigate the mechanisms underlying the arrhythmogenic side effects of roxithromycin, we studied the molecular mechanisms of roxithromycin on human ether-à-go-go-related gene (hERG) K(+) channels expressed in human embryonic kidney (HEK293) cells. Roxithromycin was found to inhibit wild-type (WT) hERG currents in a concentration-dependent manner with a half-maximum block concentration (IC50) of 55.

CYP3AP1*3 allele is associated with lipid-lowering efficacy of simvastatin and atorvastatin in Chinese women.

Response to statin therapy for cardiovascular disease is variable among different individuals. The authors aimed to investigate the effect of the CYP3AP1*3 polymorphism on the lipid-lowering efficacy of statins. They recruited 379 unrelated hyperlipidemic patients: 202 (103 men) treated with simvastatin and 177 (87 men) with atorvastatin as single-agent therapy (20 mg day(-1) orally) for 4 weeks.