AChRAbs are present in the 40–90% of patients with MG and allow, together with other antibodies (against MuSK, Lrp4, agrin, etc.), the subclassification of different 9 types of MG, particularly the first 4 types (early onset MG, late onset MG, thymoma-associated MG, and ocular MG) [39]. The gene discussed is MUSK; the disease is myasthenia gravis.