ABCB1 and epilepsy: Unfortunately, the initial progress in the genetic studies of pharmacoresistance in epilepsy was hampered by the controversy involving the putative association of a specific polymorphism in the ABCB1 gene with pharmacologic response in patients with epilepsy,30, 32, 33, 34, 35, 36, 37, 38, 167 which recent larger studies and meta‐analyses have refuted.39, 168, 169, 170, 171