CDKN2A and meningioma: Intrinsic risk factors for meningioma include age, sex, ethnic group, and family history; genetic polymorphisms of Turner syndrome, Werner syndrome, and neurofibromatosis type 2; and family cancer syndromes, including neurofibromatosis type I (NF1), patched mutations (PTCH), CREB-binding protein (CREBBP), Von Hippel-Lindau (VHL), Phosphatase and Tensin Homolog deletion (PTEN), and the cyclin-dependent kinase inhibitor 2A (CDKN2A) genes.