Congenital myasthenic syndromes (CMS) are neuromuscular transmission disorders caused by mutations in genes encoding neuromuscular junction proteins. CMS due to choline acetyltransferase (CHAT) gene is characterized by episodic apnea. The CHAT gene encodes choline acetyltransferase, which is an enzyme responsible for the biosynthesis of the neurotransmitter acetylcholine in the brain. The choline O-acetyltransferase (CHAT) gene has been associated with various human disorders that involve cognitive impairment or deficiency. Choline acetyltransferase (CHAT) gene mutations cause a rare presynaptic congenital myasthenic syndrome due to impaired acetylcholine resynthesis.