By contrast, MDS consists of severe classical lissencephaly associated with other symptoms, such as facial anomalies, and MDS patients have larger heterozygous deletions that include the PAFAH1B1 (LIS1) and YWHAE (14-3-3ε) genes, compared with patients with ILS. The gene discussed is PAFAH1B1; the disease is lissencephaly spectrum disorders.