In this subtype, MYC expression may also be elevated through additional non-coding mechanisms: (1) PVT1-MYC fusions exist in 60% of MYC-amplified cases, and the long non-coding RNA PVT1 creates a positive feedback loop to maintain high MYC expression [37]; (2) the MYC amplicon contains a medulloblastoma-specific enhancer (high histone H3K27 acetylation clusters) to enforce high MYC expression (see also Section 3.2) [64]. The gene discussed is PVT1; the disease is medulloblastoma.