NF2 and meningioma: Furthermore, Bayley et al. combined DNA methylation analysis, RNA expression, NF2 status and degree of chromosomal instability to develop a system with three methylation groups of meningiomas, where the subtype MenG C meningioma was linked to a higher ratio of copy number alterations and, similarly to the MG3 and MG4 as well as HM groups of meningiomas, was associated with the worst clinical outcomes [106].