Genes associated with channelopathies (SCN4A, CACNA1S, KCNJ2, CLCN1) or congenital myasthenic syndrome and related disorders (CHRNA1, CHRNB1, CHRND, CHRNE, RAPSN, CHAT, MUSK, COLQ, DOK7, AGRN, GFPT1, DPAGT1, LAMB2, CHRNG, PLEC) were specifically checked. The gene discussed is CHRND; the disease is congenital myasthenic syndrome.