AAV9 efficiently infected CMs as demonstrated by real-time PCR amplification of the RFP reporter gene (Figure 4b) and by epifluorescence (Figure 4d; Supplementary Figure 6A); infection of mutated HO-CMs induced overexpression of CASQ2 gene (Figure 4b) and restoration of expression of the protein (Figures 4c and d), as in CMs differentiated from control iPSCs. The gene discussed is CASQ2; the disease is infection.