The flaw leading to DMD prevents the formation of any dystrophin, while that of BMD allows some protein to be made, accounting for the differences in severity and onset between the two diseases.
The goal is to allow the existing muscle cells to use the new gene to produce the dystrophin it cannot make with its flawed gene.
The muscle tissue can also be stained to detect the presence or absence of particular proteins, including dystrophin.
Both DMD and BMD are caused by flaws in the gene for the protein called dystrophin.
Gene therapy introduces good copies of the dystrophin gene into muscle cells.