NF2 and meningioma: While low-grade NF2 mutant meningiomas generally only exhibit loss of chromosome 22 (harboring the NF2 gene) and do not harbor any other recurrent mutations or chromosomal aberrations, high-grade NF2 mutant meningiomas generally harbor a more aberrant genome with several recurrent chromosomal gains and losses (including the loss of chr 4p, 6q, 7p, 9p, 10q, 11p, 14q, and 18q, and gain of chr 17q and 20q) in addition to functional NF2 inactivation/chromosome 22 loss.