Mutations in the MTM1 gene lead to congenital myopathy called X-linked myotubular myopathy (XLMTM, MIM # 310400, ORPHA: 596) as a subtype of centronuclear myopathies group, first described in 1966 by Spiro et al. [5]. The gene discussed is MTM1; the disease is X-linked myotubular myopathy.