SMO and meningioma: While inactivating mutations in NF2 have been described in 30 to 60% of sporadic meningiomas, recent studies have shown that non-NF2 meningiomas harbor activating mutations in SMO (L412F and W535L), AKT1 (E17K), and KLF4 (K409Q), as well as inactivating mutations of TRAF7 [6, 7].