These results indicate that MTAP expression can serves as a reliable surrogate marker of CDKN2A status in meningiomas at dilutions of 1:200 and 1:100 (antibody; Abnova Anti-MTAP Monoclonal (2G4)), but its sensitivity diminishes with a different antibody at a dilution of 1:1200 (antibody; Protein Tech Anti-MTAP Polyclonal). The gene discussed is MTAP; the disease is meningioma.