NF1 and glioma: However, all 18 of these NF1-associated gliomas belonging to the molecular low-grade group formed a distinct cluster separate from other recognized reference entities including sporadic pilocytic astrocytomas belonging to the supratentorial, midline, and posterior fossa subclasses based on t-distributed stochastic neighbor embedding (tSNE) and unsupervised hierarchical clustering analyses (Fig. 5, Supplementary Figs. 4–5 [Online Resource 2]).