A patient (S100) with a 115-kb microdeletion at 17p13.3 that disrupts the PAFAH1B1 ( LIS1 ) gene. A) A local view of the 17p13.3 deletion. The proximal breakpoint is within intron 2 of METTL16, a gene that encodes methyltransferase-like 16 protein whose exact function has not been characterized. The distal breakpoint is within intron 1 of PAFAH1B1 (LIS1), a known causative gene for lissencephaly. The black arrows are the direction of transcription. B) The clinical features of a patient with a prominent forehead and micrognathia. C) Structural MRI analysis showed grade III lissencephaly. D) Analyses by qPCR confirmed that the copy number loss in this patient was de novo using three different primers (P1-P3) within the PAFAH1B1 and analyses of both parents. *p < 0.01, proband vs parents and control.