congenital myasthenic syndrome 2C

Congenital myasthenic syndrome 2C is a neuromuscular junction disorder characterized by early-onset muscle weakness. It is caused by compound heterozygous mutations in the CHRNB1 gene, which plays a critical role in acetylcholine receptor function at the postsynaptic membrane. The condition typically presents in infancy with difficulties such as feeding challenges and respiratory insufficiency. It is inherited in an autosomal recessive manner, and precise prevalence estimates are not well established.

The clinical presentation of congenital myasthenic syndrome 2C is dominated by feeding difficulties and respiratory insufficiency, features that are reported in all affected individuals. Electromyography consistently demonstrates a decremental response of the compound muscle action potential following repetitive nerve stimulation. Not all individuals experience every symptom to the same extent, and severity varies considerably.

Congenital myasthenic syndrome 2C is linked to mutations in the CHRNB1 gene, which is essential for proper acetylcholine receptor assembly and function at the neuromuscular junction. The disruption in this gene leads to impaired synaptic transmission and subsequent muscle weakness. The condition is inherited in an autosomal recessive pattern, meaning that both parents must carry a mutation for a child to be affected. Genetic counseling is recommended to help families understand the recurrence risk and implications for family planning.

Currently, management focuses on supportive care and symptom management because there are no specific foundational therapies or FDA-approved treatments for congenital myasthenic syndrome 2C. Treatment is individualized and typically involves a multidisciplinary care team to provide regular surveillance and monitoring of respiratory function, feeding, and overall muscle strength. Families are encouraged to discuss available supportive options with their healthcare providers, and genetic counseling is advised to further assist in understanding treatment strategies and family planning.

The outlook for congenital myasthenic syndrome 2C varies widely among individuals, with outcomes depending on symptom severity and the effectiveness of supportive interventions. Many affected individuals experience improvements in quality of life with tailored management, though some may require ongoing respiratory support or other interventions. Outcomes described in medical literature continue to evolve as standards of care improve, and regular surveillance can help detect emerging issues before they become severe. Families often find it helpful to connect with specialists experienced in managing this condition and to seek genetic counseling for additional guidance.