hello. Maybe you can detect mRNA or protein expression firstly.
The following article: https://www.nature.com/articles/gt2009120#Sec8 ( Dose-dependent restoration of dystrophin expression in cardiac muscle of dystrophic mice by systemically delivered morpholino), Fig 2: "normal dystrophin mRNA containing exon 23" is detected in C2C12 myoblasts (C2C12 ) and mouse cardiomyoblasts.