N-Acetyltransferase 2 (NAT2) Genotype, Varies
Use
This assay identifies patients at risk for altered metabolism of drugs metabolized by arylamine N‑acetyltransferase type 2—such as isoniazid—by assigning NAT2 genotype and predicting acetylator phenotype (slow, intermediate, or rapid) based on haplotype combinations. Genotypes guide metabolizer phenotype inference to support dosing decisions and reduce risk of adverse reactions.
Special Instructions
Required informed consent documentation for New York clients; forms available include ‘Informed Consent for Genetic Testing’ (English and Spanish). Additional requisition forms required include Neurology Specialty Testing or Therapeutics Test Request. Multiple genotype tests can be performed on a single specimen after extraction; specimens in the ‘Multiple Genotype Test List’ including NAT2Q can be submitted together.
Limitations
Some rare NAT2 variants may not be detected by this method. Cis/trans status of multiple variants may not be resolved, potentially yielding ambiguous diplotypes. Post-transplant or transfusion samples (blood or liver transplant, or recent transfusion) may contain donor DNA and not reflect recipient genotype. Absence of detected variants does not rule out other undetected variants.
New York Approved
Methodology
PCR-based (PCR)
Biomarkers
LOINC Codes
- 101141-0
- 101142-8
- 101143-6
- 69047-9
- 48767-8
- 85069-3
- 62364-5
- 18771-6
Result Turnaround Time
3-8 days
Related Documents
For more information, please review the documents below
Specimen
Whole Blood
Volume
3 mL
Minimum Volume
0.4 mL
Container
Lavender top (EDTA)
Collection Instructions
Invert several times to mix blood; send in original tube without aliquoting.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 9 days |
| Refrigerated | 30 days |