Centronuclear myopathy is a condition characterized by muscle weakness (myopathy) and wasting (atrophy) in the skeletal muscles, which are the muscles used for movement. The severity of centronuclear myopathy varies among affected individuals, even among members of the same family.
Centronuclear myopathy is most often caused by mutations in the DNM2, BIN1, or TTN gene. The proteins produced from the DNM2 and BIN1 genes are involved in endocytosis, a process that brings substances into the cell. The protein produced from the BIN1 gene plays an additional role in the formation of tube-like structures called transverse tubules (or T tubules), which are found within the membrane of muscle fibers. These tubules help transmit the electrical impulses necessary for normal muscle tensing (contraction) and relaxation. The protein produced from the DNM2 gene also regulates the actin cytoskeleton, which makes up the muscle fiber's structural framework. DNM2 and BIN1 gene mutations lead to abnormal muscle fibers that cannot contract and relax normally, resulting in muscle weakness.
Centronuclear myopathy is a rare condition; its exact prevalence is unknown.
When centronuclear myopathy is caused by mutations in the DNM2 gene, it is inherited in an autosomal dominant pattern, which means one copy of the altered DNM2 gene in each cell is sufficient to cause the disorder. Rarely, BIN1 gene mutations that are inherited in an autosomal dominant pattern can cause centronuclear myopathy.
Published Date: November 01, 2015Published By: National Institutes of Health