CDKN2B and central nervous system cancer: Currently, genetic studies have identified a large amount of potential oncogenes or tumor suppressors in glioma, such as cyclin dependent kinase inhibitor 2B (CDKN2B) and regulator of telomere elongation helicase 1 (RTEL1) [3], isocitarte dehydrogenase (NADP+) 1 cytosolic (IDH1) [4], telomerase reverse transcriptase (TERT) and telomerase RNA component (TERC) [5].