on physical mobility aids such as wheelchairs and stand aids, but this latter variety is so rare that only two cases are known to the CNM "community". Approximately 80% of males with a diagnosis of myotubular myopathy by muscle biopsy will have a mutation in MTM1 identifiable by genetic sequence analysis. Many patients with myotubular myopathy die in infancy prior to receiving a formal diagnosis. When possible, muscle biopsy and genetic testing may still be helpful even after a neonatal death, since the diagnostic information can assist with family planning and genetic counseling as well as aiding in the accurate diagnosis of any relatives who might also have the same genetic abnormality. History In 1966, Dr. Spiro (a New York City neurologist) published a medical report of a boy with myopathy, which upon muscle biopsy, showed that the nuclei of the muscle cells were located in the center of the muscle cells, instead of their normal location of the periphery. The nuclear appearance reminded him of the nucleus-in-the-center appearance during the "myotubular" stage of embryonic development. Thus, he coined the term "myotubular myopathy". Spiro speculated that the embryonic muscle development he had seen in the boy was due to growth arrest during the myotubular phase, causing the myopathy. More than three decades later, it is not fully understood whether this theory regarding halted (or delayed) embryonic muscle development is correct. Some research suggests that this theory may be acceptable for infant-onset myotubular myopathy (mutations at the MTM1 gene on the X chromosome) but may not be acceptable for the autosomal forms of centronuclear myopathy, while other research suggests that the growth arrest mechanism may be responsible for all forms of MTM and CNM. Regardless of whether the myopathy is caused by arrest at the "myotubular" stage, for historical reasons the name myotubular myopathy persists and is widely accepted. As a reference to the term myotubular myopathy (MTM), when a genetic abnormality on the X chromosome was determined to be involved in a substantial percentage of individuals with the myotubular/centronuclear appearance on muscle biopsy, researchers named the gene segment MTM1. Similarly, the protein typically produced by that gene is called "myotubularin". Advocacy There are several global advocacy groups working closely to educate newly affected families on care guidelines. The Joshua Frase Foundation is a comprehensive resource for care guidelines for Centronuclear myopathies. In the United States, children with congenital myopathies often