NF2 and meningioma: Of the widespread genomic disruption observed in high-grade meningioma, the single most frequent event is arm-level loss of chromosome 22, which is postulated to drive bi-allelic inactivation of NF2. In line with this hypothesis, we found that mutations in NF2 occur in 75% of meningiomas with loss of chromosome 22, but in less than 1% of samples without such loss.