CYP2A7 and neoplasm: Sequencing of the tumor DNA revealed mutations clustered in the mucin (MUC4, MUC6, MUC17, and MUC20), HLA (HLA-A, HLA-B, HLA-C, HLA-DQA, HLA-DQB, and HLA-DBR), zinc finger (ZNF221, ZNF417, ZNF517, ZNF595, ZNF774, and ZNF831), cytochrome p450 (CYP2A7, CYP27C1), DNA repair (GADD45B, MSH4, and TDG), and cell cycle regulating gene families (MCM4, RBBP8NL, PER3, CDK11B, CDC27, CCNE1, and TP53).