CYP2C19
Also known as: 2C19GENO
Use
This test assesses genetic risk of abnormal drug metabolism for CYP2C19 substrates. It may aid in drug selection and dose planning for drugs metabolized by CYP2C19 by identifying variations in the CYP2C19 gene that affect enzyme function. These variations can predict or explain non-standard dose requirements, therapeutic failure, or adverse reactions. The CYP2C19 gene is involved in the metabolism of many drugs.
Special Instructions
Counseling and informed consent are recommended for genetic testing, especially required for New York patients. The test cannot be ordered without informed consent due to the nature of genetic testing.
Limitations
The test detects only targeted CYP2C19 gene variants; it does not detect other genetic or non-genetic factors that may influence drug metabolism. Publicly available resources such as PharmVar or PharmGKB provide phenotype prediction and allele frequency guidance. The test's results should not replace therapeutic drug or clinical monitoring. Diagnostic errors may occur due to rare sequence variations, and assumptions about allele phase content are made for results assignment.
New York Approved
Methodology
PCR-based (PCR)
Biomarkers
LOINC Codes
- 79714-2
- 31208-2
- 57132-3
- 50398-7
- 11526-1
Result Turnaround Time
5-10 days
Related Documents
For more information, please review the documents below
Specimen
Whole Blood
Volume
3 mL
Minimum Volume
1 mL
Container
Lavender (EDTA), pink (K2EDTA), or yellow (ACD solution A or B)
Storage Instructions
Preferred transport temp: Refrigerated.
Causes for Rejection
Plasma or serum. Specimens collected in sodium heparin or lithium heparin. Frozen specimens in glass collection tubes.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 3 days |
| Refrigerated | 1 week |
| Frozen | 1 month |
Other tests from different labs that may be relevant