Studies on malignant glioma have shown that deletion mutations of CDKN2A can be seen in 40.3% of cases, of which homozygous deletion accounts for 74%, and homozygous deletion is more common in patients with primary malignant glioma (Cen et al., 2012; Hu et al., 2021a). The gene discussed is CDKN2A; the disease is malignant glioma.