P450 CYP2C9

Test Description:

The cytochrome P450 2C family is responsible for metabolizing a variety of exogenous and endogenous substrates. The human cytochrome P450-2C9 gene spans a region of approximately 55 kilobases and is composed of nine exons. The gene resides on chromosome 10 (q24) and is clustered among other closely related 2C genes in the order: Cen-2C18-2C19-2C9-2C8-Tel. The 2C9 variant nomenclature adopted follows that outlined by the Human Cytochrome P450 (CYP) Allele Nomenclature Committee. Variants are accordingly classified as *2 to *12. The test screens for the five most common variants seen across various ethnic groups (2C9*2 – 2C9*6).


1. De Morais SM, Schweikl H, Blaisdell J, Goldstein JA. 1993. Gene structure and upstream regulatory regions of human CYP2C9 and CYP2C18. Biochem Biophys Res Commun. 194:194-201.
2. Gray IC, Nobile C, Muresu R, Ford S, Spurr NK. 1995. A 2.4-megabase physical map spanning the CYP2C gene cluster on chromosome 10q24. Genomics. 28:328-332.
3. http://www.imm.ki.se/CYPalleles/
4. Haining R. L., Hunter, A. P.,Veronese, M. E., Trager, W. F and Rettie, A. E. 1996. Allelic variants of human cytochrome P450 2C9: Baculovirusmediated expression, purification, structural characterization, substrate stereoselectivity and prochiral selectivity of the wild-type and I359L mutant forms. Arch Biochem Biophys. 333:447-58.
5. Lee, C. R., Goldstein, J. A. and Pieper, J. A. 2002. Cytochrome P450-2C9 polymorphisms: a comprehensive review of the in-vitro and human data. Pharmacogenetics 12:251-263.
6. Kirchheiner J and Brockmoller J. 2005. Clinical consequences of cytochrome P450 2C9 polymorphisms. Clin Pharmacol Ther. 77:1-16.

Specimen Requirements:

Two 5-10 ml tubes of anticoagulated blood. The preferred anticoagulant is EDTA (lavendar top tubes), ACD (yellow top) tubes are also accepted.

Shipping: Send at room temperature.

Turnaround Time: 7-10 days

CPT Codes: 83891, 83900, 83901x3, 83914x3, 83912

Consent Form: Pharmacogenic Testing Consent [PDF]

Requisition Form: General Test Requisition [PDF]