NPPB and cardiac hypertrophy: Further evidence of the development of cardiac hypertrophy and cardiomyopathy in Mrps5cKO mice includes the upregulation of the hypertrophy and disease marker genes (Nppa, Nppb, and Myh7) and fibrosis marker genes (Col1a1, Col1a2, and Col1a3) in Mrps5cKO hearts (Fig. 1p).