Characterization of an induced pluripotent stem cell line from a long QT syndrome type 1 patient possessing the KCNQ1 c.691C > T (p.Arg231Cys) variant.

Long QT syndrome type 1 (LQT1), the most prevalent subtype, is attributed to variants in KCNQ1, and is characterized at the cell level by diminished slow delayed rectifier potassium current and disrupted cardiomyocyte repolarization. At the patient level, impaired ventricular repolarization prolongs the QT interval on the electrocardiogram and is associated with life-threatening arrhythmias, often precipitated by physical exertion. Here, an induced pluripotent stem cell line was reprogrammed from an individual carrying the KCNQ1 c.691C > T (p.Arg231Cys) variant with a family history of sudden death; the line demonstrates normal stem cell morphology and karyotype, differentiation capacity, and pluripotency, enabling disease modeling.