In the neuromuscular junction there is a vital pathway that maintains synaptic structure and results in the aggregation and localization of AChR on the postsynaptic folds. This pathway consists of agrin, muscle-specific tyrosine kinase (MuSK), acetylcholine receptors (AChRs) and the AChR-clustering protein rapsyn, encoded by the RAPSN gene. The vast majority of mutations causing CMS are found in the AChR subunits and rapsyn genes.Out of all mutations associated with CMS, more than half are mutations in one of the four genes encoding the adult acetylcholine receptor (AChR) subunits. Mutations of the AChR often result in endplate deficiency. Most of the mutations of the AChR are mutations of the CHRNE gene. The CHRNE gene codes for the epsilon subunit of the AChR. Most mutations are autosomal recessive loss-of-function mutations and as a result there is endplate AChR deficiency. CHRNE is associated with changing the kinetic properties of the AChR. One type of mutation of the epsilon subunit of the AChR introduces an Arginine into the binding site at the α/ε subunit interface of the receptor. The addition of a cationic Arg into the anionic environment of the AChR binding site greatly reduces the kinetic properties of the receptor. The result of the newly introduced Arg is a 30-fold reduction of agonist affinity, 75-fold reduction of gating efficiency, and an extremely weakened channel opening probability. This type of mutation results in an extremely fatal form of CMS.Another common underlying mechanism of CMS is the mutation of the rapsyn protein, coded by the RAPSN gene.
The effect of ephedrine is delayed and the improvement occurs over a period of months.Salbutamol, a selective β(2)-adrenergic receptor agonist, has been found, in adults, to have fewer side effects than Ephedrine and to be more easily obtained in some countries. It has been trialed in children with positive resultsAs of 2022, the standard of care for DOK7  CMS is either ephedrine or salbutamol. People
Two brothers with apparent myasthenic syndrome with a seemingly circadian off/on cycle, living near Quetta, Pakistan were nicknamed the solar kids, because their condition resulted in an inability to move from approximately sunset to sunrise, while their daytime motor abilities were seemingly normal. Doctors observed that some "factor" seemed to become exhausted in the course of normal diurnal activities, and was "recharged" over the period of inertia and sleep. The father first sought help from spiritual healers, then turned to Western medicine. A younger brother of the two had also begun to manifest the same symptoms. The family had other children, two daughters and one son, who were unaffected. The "solar kids" condition, despite extensive testing, was said to be undiagnosed as of 2016, and assumed to be genetic, as their parents were cousins. Samples of their genetic material were to be sent to the UK for analysis. See also
Congenital disorder
Myasthenia gravis
Lambert-Eaton syndrome

References
External links
Congenital Myasthenic Syndromes
About Congenital Myasthenic Syndrome From the Mayo Clinic
Treatment for Congenital Myasthenic Syndromes From the Mayo Clinic