A Mhc transgene carrying an amino acid substitution equivalent to the K146N (dominant) mutation in human beta-cardiac myosin heavy chain that causes hypertrophic cardiomyopathy. (FlyBase curator comment: the mutation in the Mhc gene is given as R146N in FBrf0240086, however analysis of the release 6.32 annotated gene model indicates the change to be R147N).