Although variants in over 50 genes have been linked to DCM, the evidence is most robust for a ‘core disease set’ encompassing the sarcomeric genes MYH7 (which encodes beta myosin heavy chain), TNNT2 (which encodes troponin T2), and TTN (encoding titin) and the gene LMNA encoding a nuclear envelope protein. This evidence concerns the gene TTN and familial dilated cardiomyopathy.