Mutations in cardiac muscle myosin and its associated proteins (e.g. C-protein; myosin binding protein C (MyBP-C)) are known to be associated with a number of myopathies (e.g. familial hypertrophic cardiomyopathy and dilated cardiomyopathy) (Watkins et al., 1992, 1995; Seidman and Seidman, 2001; Tajsharghi et al., 2003). The gene discussed is MYBPC3; the disease is dilated cardiomyopathy.