TTN and familial dilated cardiomyopathy: To give a sense of scale of this problem, titin, the largest human protein has over 7,000 VUS alone, which are linked to at least four cardiac diseases including familial cardiomyopathies DCM (Dilated Cardiomyopathy, most common), RCM (Restrictive Cardiomyopathy) and HCM (Hypertrophic Cardiomyopathy) as well as ACM (Arrhythmogenic Cardiomyopathy) (18).