TPMT Genotype

Test Code

TPMT

Alias/See Also

TPMT Genotype

Quest Code
377428

CPT Codes
81401

Preferred Specimen

5 mL whole blood collected in an EDTA (lavender-top) tube

Minimum Volume

3 mL

Other Acceptable Specimens

5 mL whole blood collected in a sodium heparin (green-top) tube
5 mL whole blood collected in an ACD-A or ACD-B (yellow-top) tube

Transport Temperature

Room temperature

Specimen Stability

Room temperature: 8 days
Refrigerated: 8 days
Frozen: unacceptable

Methodology
Polymerase Chain Reaction (PCR), Single Nucleotide Primer Extension

This test was developed and its performance characteristics have been determined by Quest Diagnostics. Performance characteristics refer to the analytical performance of the test

Setup Schedule

Tuesday, Friday a.m.

Report Available

8 days

Limitations

This test detects 95% of the mutations in the TPMT gene and thus not all intermediate or slow metabolizers will be identified.

Clinical Significance

This test detects common deficiency variants in the TPMT gene and therefore identifies individuals who are at risk of developing serious adverse effects when administered thiopurine drugs.

Performing Laboratory
Quest Diagnostics Nichols Institute
San Juan Capistrano, CA

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.