Manifesting carriers are described by the Muscular Dystrophy Campaign as being carriers of a condition, who may exhibit symptoms such as muscle weakness. Generally though, female carriers only carry one faulty copy of a gene and do not develop the full-blown disease. Most female carriers of x-linked myotubular myopathy are reported to be free from symptoms.
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X-inactivation patterns in carriers of X-linked myotubular myopathy.