Two of the screened individuals appeared to be carriers of both the familial variants in this family, four of six screened individuals carried the TNNT2-variant with or without development to DCM, showing the importance of a careful family history, structured family screening based on systematic pedigree analysis, clinical examination, and genetic testing in suspicion of an inherited cardiac disease, which can dramatically alter the future for the other affected family members or the individuals at risk for the disease. This evidence concerns the gene TNNT2 and familial dilated cardiomyopathy.