PAFAH1B1 and Epileptic spasm: Classical lissencephaly is most often related to pathogenic variants in PAFAH1B1/LIS1 and DCX, and in affected cohorts epileptic spasms have been reported in up to 80% of children with these genetic forms, which confirms that disruption of the microtubule and migration machinery has a strong epileptogenic effect in early life.