👉 Myotosis is a genetic disorder that affects muscle development and function. It typically starts in childhood or adolescence, causing abnormal growth of muscles and bones. The symptoms can vary greatly from person to person, with some people experiencing severe muscle weakness, spasms, and pain, while others may have normal muscle strength but no noticeable deformities. Myotosis is caused by a mutation in the myogenin gene that leads to an inability of muscle cells to make their own growth factors, which are essential