In 6 of 10 cases of sporadic DCM and in single cases of RCM and HCM, we found de novo mutations in genes previously associated with cardiomyopathy (CRYAB, DSP, MYH7, SCN5A, TNNC1, and TTN). This evidence concerns the gene TNNC1 and cardiomyopathy, familial restrictive, 1.