CYP2A13（cytochrome P450 family 2 subfamily A member 13），癌症关联基因，基因ID：1553，该基因编码细胞色素P450酶超家族的一个成员细胞色素p450蛋白是一种单加氧酶，催化药物代谢和胆固醇、类固醇等脂类的合成。这种蛋白质定位于内质网尽管其内源底物尚未确定，但已知其代谢4-（甲基亚硝胺）-1-（3-吡啶基）-1-丁酮，这是烟草特有的一种主要亚硝胺。该基因是来自染色体19q上cyp2a、cyp2b和cyp2f亚家族的一大簇细胞色素p450基因的一部分。This gene encodes a member of the cytochrome P450 superfamily of enzymes. The cytochrome P450 proteins are monooxygenases which catalyze many reactions involved in drug metabolism and synthesis of cholesterol， steroids and other lipids. This protein localizes to the endoplasmic reticulum. Although its endogenous substrate has not been determined， it is known to metabolize 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone， a major nitrosamine specific to tobacco. This gene is part of a large cluster of cytochrome P450 genes from the CYP2A， CYP2B and CYP2F subfamilies on chromosome 19q. [provided by RefSeq， Jul 2008]。