PAFAH1B1 and classic lissencephaly: About 60% of ILS cases are associated with the haploinsufficiency of PAFAH1B1 [5], while patients with MDS have larger deletions between PAFAH1B1 and YWHAE, resulting in additional symptoms including short stature, facial deformities and variable congenital malformations depending on the size of the deletion [6].