Thereafter, the 29 NF2-altered WHO grade I meningiomas were individually compared by performing unsupervised hierarchical clustering of the tumours based on significant immunological signature gene sets with GSVA analysis, revealing two molecular clusters that mostly matched meningiomas in patients with NF2 and sporadic NF2-altered meningiomas (Additional file 1: Figure S2D, Additional file 2: Table S5). This evidence concerns the gene NF2 and meningioma.