Clinical and molecular genetic study of a patient with nemaline myopathy
DOI:
https://doi.org/10.67667/NEU.v27i2.240Keywords:
nemaline myopathy, NEB gene, Z-line filamentsAbstract
The term congenital myopathy refers to a group of clinically, genetically and histologically heterogeneous disorders that primarily affect muscle tissue. The presence of specific histopathological changes in muscle biopsy distinguishes these conditions from other neuromuscular diseases. Congenital myopathy is caused by genetic mutations responsible for the formation of defective structural proteins localized in skeletal muscle. (8) Nemaline myopathy is characterized by the presence of small rod-like inclusions within muscle fibers.
These structures are mainly composed of alpha-actinin, actin, and other Z-line filaments. (3) It is considered the most common form of congenital myopathy (9), with an estimated incidence of approximately 1:50,000 live births. (15) To date, six genes associated with the development of Nemaline myopathy have been identified, with the NEB and ACTA1 genes being the most significant. Mutations in the NEB gene are considered the most common cause of the disease. (6) We present an 15-year-old Bulgarian patient with a genetically confirmed diagnosis of Nemaline myopathy caused by a mutation in the NEB gene.
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