TNNT2 and familial dilated cardiomyopathy: When this transgene was introduced into heterozygous null Tnnt2+/− mice lacking one endogenous allele of Tnnt2 (Tnnt2+/−/TGK210Δ), they displayed findings typical of severe DCM, including significant left ventricular dilation, poor contractility, conduction delays, repolarization abnormalities, and inducible ventricular tachyarrhythmias.