Comparison of MYOM3 fragments with three other assays (biopsy, restoration of physical force and CK) in models of two different muscular dystrophies, mdx (dystrophin deficient) and KO-Sgca (α-sarcoglycan deficient), demonstrated the superiority of MYOM3 fragments for the follow-up of gene therapy treatments relative to other assays. The gene discussed is MYOM3; the disease is muscular dystrophy.