CYP2E1 and nasopharyngeal carcinoma: Genes linked to NPC include HLA-A (Human leukocyte antigen A) [8, 9], HLA-B (Human leukocyte antigen B) [10], GABBR1 (Gamma-aminobutyric acid (GABA) B receptor 1) [11], CYP2E1 (cytochrome P450 2E1) and hOGG1 (human 8-oxoguanine DNA N-glycosylase 1) [12].