Question: How many people are affected by congenital myasthenic syndrome ?
Answer: The prevalence of congenital myasthenic syndrome is unknown. At least 600 families with affected individuals have been described in the scientific literature.
Source: GHR

Question: What are the genetic changes related to congenital myasthenic syndrome ?
Answer: Mutations in many genes can cause congenital myasthenic syndrome. Mutations in the CHRNE gene are responsible for more than half of all cases. A large number of cases are also caused by mutations in the RAPSN, CHAT, COLQ, and DOK7 genes. All of these genes provide instructions for producing proteins that are involved in the normal function of the neuromuscular junction. The neuromuscular junction is the area between the ends of nerve cells and muscle cells where signals are relayed to trigger muscle movement. Gene mutations lead to changes in proteins that play a role in the function of the neuromuscular junction and disrupt signaling between the ends of nerve cells and muscle cells. Disrupted signaling between these cells results in an impaired ability to move skeletal muscles, muscle weakness, and delayed development of motor skills. The respiratory problems in congenital myasthenic syndrome result from impaired movement of the muscles of the chest wall and the muscle that separates the abdomen from the chest cavity (the diaphragm). Mutations in other genes that provide instructions for proteins involved in neuromuscular signaling have been found to cause some cases of congenital myasthenic syndrome, although these mutations account for only a small number of cases. Some people with congenital myasthenic syndrome do not have an identified mutation in any of the genes known to be associated with this condition.
Source: GHR

Question: Is congenital myasthenic syndrome inherited ?
Answer: This condition is most commonly inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. Rarely, this condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In some cases, an affected person inherits the mutation from one affected parent. Other cases result from new mutations in the gene and occur in people with no history of the disorder in their family.
Source: GHR

Question: What are the treatments for congenital myasthenic syndrome ?
Answer: These resources address the diagnosis or management of congenital myasthenic syndrome: - Gene Review: Gene Review: Congenital Myasthenic Syndromes - Genetic Testing Registry: CHRNA1-Related Congenital Myasthenic Syndrome - Genetic Testing Registry: Congenital myasthenic syndrome - Genetic Testing Registry: Congenital myasthenic syndrome 1B, fast-channel - Genetic Testing Registry: Congenital myasthenic syndrome with tubular aggregates 1 - Genetic Testing Registry: Congenital myasthenic syndrome, acetazolamide-responsive - Genetic Testing Registry: Endplate acetylcholinesterase deficiency - Genetic Testing Registry: Familial infantile myasthenia - Genetic Testing Registry: Myasthenia, limb-girdle, familial - Genetic Testing Registry: Myasthenic syndrome, congenital, associated with acetylcholine receptor deficiency - Genetic Testing Registry: Myasthenic syndrome, slow-channel congenital These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care
Source: GHR