CYP17A1（cytochrome P450 family 17 subfamily A member 1），癌症关联基因，基因ID：1586，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。它具有17α-羟化酶和17，20-裂解酶活性，是类固醇生成途径中的关键酶，产生孕激素、盐皮质激素、糖皮质激素、雄激素和雌激素。该基因突变与类固醇-17α羟化酶缺乏症、17α羟化酶/17、20-裂合酶缺乏症、假两性畸形和肾上腺增生有关。[由RefSeq提供，2008年7月]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. It has both 17alpha-hydroxylase and 17，20-lyase activities and is a key enzyme in the steroidogenic pathway that produces progestins， mineralocorticoids， glucocorticoids， androgens， and estrogens. Mutations in this gene are associated with isolated steroid-17 alpha-hydroxylase deficiency， 17-alpha-hydroxylase/17，20-lyase deficiency， pseudohermaphroditism， and adrenal hyperp。