MODEL RELEASED. Myopathy genetic research. Myopathy researcher studying a cell culture under a light microscope. On the screen is the result of an electrophoresis gel experiment to sequence a section of DNA (deoxyribonucleic acid). Myopathies are a group of neuromuscular diseases in which the muscle fibres do not function properly, resulting in muscular weakness. Myopathies may be autoimmune, where the body's immune system attacks the muscles, due to metabolism defects, or congenital (present from birth). Photographed at the French Association for Combating Myopathy (AFM).