AGRN and congenital myasthenic syndrome: Identification of specific genetic aetiologies within a condition can also have important implications for treatment, as illustrated by this patient for whom treatment with acetazolamide led to significant reduction in episodic symptoms and by our findings in three patients with congenital myasthenic syndrome involving COLQ and AGRN (Additional file 1: Table S2) which contraindicate classic treatment using cholinesterase inhibitors [26, 27].