POLR2A and meningioma: In particular, AKT1, KLF4, SMO, or POLR2A mutations were significantly more frequent in meningiomas of paraxial mesodermal origin than in those of neural crest (p = 1.7 × 10–10) and dorsal mesodermal origin (p = 3.0 × 10–4) (Fig. 3F).