CHRNA4 and myasthenia gravis: MG is the first and, so far, only autoimmune disease with well-defined autoantigen target; the binding of nAChR by MG antibodies leads to complement-mediated lysis of the postsynaptic structure and internalization of the receptor, thereby disrupting neuromuscular transmission (Engel and Arahata, 1987; Drachman et al., 1978; Gomez et al., 2010).