Perioral skin biopsy to study skeletal muscle protein expression

Clinical trials for muscular dystrophy molecular treatment require multiple sampling of skeletal muscle to monitor protein rescue. This practice is invasive and could raise ethical problems. A less invasive tool to obtain sequential muscle sampling is necessary. Using indirect immunofluorescence, we evaluated muscle protein expression in myofiber bundles included in 2-2.5-mm punch skin biopsies from the perioral region from 6 healthy subjects and 6 patients with genetically defined forms of muscular dystrophy. Large intradermal bundles of orbicularis oris muscle were constantly present in skin biopsies. They showed a typical muscular antigenic pattern in controls and the expected protein defect in muscular dystrophy patients. These results demonstrate the feasibility of muscular protein expression analysis using skin biopsy. We propose this minimally invasive technique to follow-up the response to genetic or conventional therapies in muscular dystrophies and to confirm the diagnosis in some special clinical conditions.