COL1A1 and heart failure: The heart weight/body weight ratio was significantly higher in Bmx/CA mice (Supplementary Fig. S2a), and expression levels of genes related to heart failure such as Nppa and Nppb as well as fibrosis marker gene Col1a1 were also higher in the heart of Bmx/CA mice compared with Ctrl mice (Fig. 2e, Supplementary Fig. S2b).