Consistent with a previous report,13 we found that SRF Ser-103 phosphorylation was decreased in mice as young as 4 weeks of age (24% less for TM54-GFP vs. NTG-GFP cohorts, p = 0.02, Figure 6), an age at which the DCM phenotype was already apparent (left ventricular ejection fraction for AAV9sc.GFP cohorts [%]: NTG - 58 ± 2, TM54 - 35 ± 5, n = 10, 5; p < 0.001 by t test). The gene discussed is SRF; the disease is familial dilated cardiomyopathy.