In addition, proteins from the mitochondrial membrane and matrix (e.g., glutaryl-CoA dehydrogenase [GCDH], cytochrome b5 type B [CYB5B], and sirtuin 3) were also less abundant, further indicating mitochondrial impairment in the myocardium of the DMD animals. The gene discussed is CYB5B; the disease is Duchenne muscular dystrophy.