The majority of DCM patients carry titin-truncated variants located in the A-band (Herman et al. 2012; Roberts et al. 2015; Akinrinade et al. 2016; Schafer et al. 2017), but in general, truncations occurring in constitutive (highly expressed) exons of titin lead to DCM (Roberts et al. 2015). The gene discussed is TTN; the disease is familial dilated cardiomyopathy.