Both groups of mice developed a comparable degree of cardiac hypertrophy in response to TAC, as shown by similarly enhanced HW/TL ratio, embryonic gene expression (decrease in Myh6 and Atp2a2, increase in Myh7 and Acta1 mRNA) and cardiomyocyte size (Fig. 3e, Supplementary Fig. 3a–f). Here, ACTA1 is linked to cardiac hypertrophy.