Fluorouracil (5-FU) is a commonly used anticancer drug. It functions by irreversibly inhibiting thymidylate synthase.

• 5-FU is widely used in a number of cancers worldwide and is in the WHO list of Essential Medicines.
• Detoxification of 5-FU is mediated by the dihydropyrimidine dehydrogenase (DPD) gene. 
• Apart from 5-FU, the gene also is involved in detoxification of Capecitabine, and Tegafur.
• Genetic variations in the gene can cause a partial or complete deficiency of function, which may lead to drug toxicity, which are severe.

Pharmacogenetic testing is recommended on the FDA Drug label
The USFDA-approved drug label for fluorouracil states that the drug is contraindicated in patients with known DPD deficiency.

CPIC Dosing Guidelines for fluoropyrimidines recommends an alternative drug for patients who are homozygous for DPYD non-functional variants as these patients are typically DPD deficient and a 50% reduction for heterozygous patients.

Genomic test request
Please write a referral on your letterhead regarding the referral and the test you would be requesting. Pack the documents with the box you would be sending across

Consent forms (one each for each patient)
The consent forms for genomic analysis needs to be signed individually by each member (or parent/guardian in case the person is a minor). Each consent needs to be counter-signed by the investigator.

• Printable Consent Form (English) 
• Printable Consent Form (Hindi)  
• Consignment information/declaration (required for the courier/postage department). Since you would be posting out blood samples, you would require to attach a declaration which should be signed/stamped and given to the courier/postage department for processing your courier. Printable consignment information form/declaration