OPA1 and familial dilated cardiomyopathy: In the DCM-dnPI3K model, there was also evidence of atrial dysfunction and gene expression changes at 8 weeks versus Ntg, but the increase in BNP was smaller (∼4-fold at 8 weeks vs. 8-fold at 20 weeks) and there was no significant fall in TFAM (Supplementary Figure S3B).