CYP2C9 Genotyping

Related Gene(s): CYP2C9

The human cytochrome P450 superfamily is responsible for metabolizing exogenous and endogenous substrates. The cytochrome P450-2C9 (CYP2C9) enzyme contributes to the metabolism of a large number of clinically relevant drug classes and drugs, including anticoagulants (eg, warfarin), sulfonylureas, NSAIDs, phenytoin, and angiotensin II blockers (eg, losartan). The CYP2C9 gene is located within a cluster of cytochrome P450 genes (centromere-CYP2C18-CYP2C19-CYP2C9-CYP2C8-telomere) on chromosome 10q23.33. The CYP2C9 gene has nine exons and is highly polymorphic, with over 60 variant star (*) alleles currently defined by the Human Cytochrome P450 Allele Nomenclature Committee.

This targeted genotyping test interrogates the following variants: Decreased function – *2, *3, *4, *5 ; no function – *6.

Specimen Requirements


  • Anticoagulated blood: Two 5-10 mL tubes with EDTA (lavender top) are preferred. ACD tubes (yellow top) are also accepted
  • Additionally, we can accept saliva specimens

Ordering Information


  • Ship at room temperature

Turnaround Time

  • 7-10 days


General Test Requisition