Also known as:DHP, DPD, DHPDHASE, dihydropyrimidine dehydrogenase, 5-FU, capecitabine, tegafur
Pharmacogenomic - Toxicity
Use of test
The protein dihydropyrimidine dehydrogenase is involved in the breakdown of various drugs. Variants in the protein's gene, DPYD, can slow the rate at which certain drugs are broken down. The drugs involved are 5-fluorouracil (5FU), capecitabine and tegafur. A patient with such a variant may be at risk of bone marrow toxicity from the medication.
The laboratory report describes the gene variants detected in a patient, and the implications regarding drug choice or dose according to current evidence-based guidelines.
This test has a role in identifying patients who may benefit from avoiding a specific drug or dose, but it provides little useful information for people (including relatives) who are not taking the medications of concern. Testing of relatives is generally not recommended.
Analysis of the DPYD gene to detect the following variants: *13 (c.1679T>G), *2A (c.1905+1G>A), c.2846A>T, HapB3 (c.[483+18G>A;1129-5923C>G;1236G>A]).
Requesting the test
This test can be requested by any medical practitioner.
4 mL blood in EDTA. Specimens may be collected by the requesting practitioner or at any Sonic Healthcare collection centre (see link below).
To help ensure the quality of the test, a genetic test should be done with a dedicated sample whenever possible i.e. a sample collected specifically for that test rather than a sample that is used for multiple tests.
We recommend that the patient or another adult check the labelling of request forms and sample tubes.