Sign in →

Test ID: DPYDV Dihydropyrimidine Dehydrogenase (DPYD) Genotype

Advisory Information

This test does not detect or report variants other than the *2A, *7, *8, *9B, *10, *11, *13, rs67376798, rs75017182, and rs115232898 alleles. Sequencing of the full gene is also available for detection of additional variants as well as the alleles listed: order DPYDG / Dihydropyrimidine Dehydrogenase (DPYD) Full Gene Sequencing.

Specimen Required

Multiple genotype tests can be performed on a single specimen after a single extraction. See Multiple Genotype Test List in Special Instructions for a list of tests that can be ordered together.


Submit only 1 of the following specimens:


Specimen Type: Whole blood

Container/Tube: Lavender top (EDTA)

Specimen Volume: 3 mL

Collection Instructions:

1. Invert several times to mix blood.

2. Send specimen in original tube.

Specimen Stability Information: Ambient (preferred)/Refrigerated


Specimen Type: Saliva

Patient Preparation: Patient should not eat, drink, smoke, or chew gum 30 minutes prior to collection.

Supplies: DNA Saliva Collection Kit (T786)

Container/Tube: Saliva Swab Collection Kit (T786: fees apply)

Specimen Volume: 1 swab

Collection Instructions: Collect and send specimen per kit instructions.

Specimen Stability Information: Ambient


Specimen Type: DNA

Container/Tube: 2 mL screw top tube

Specimen Volume: 100 mcL (microliters)

Collection Instructions:

1. The preferred volume is 100 mcL at a concentration of 50 ng/mcL.

2. Include concentration and volume on tube.

Specimen Stability Information: Frozen (preferred)/Ambient/Refrigerated


New York Clients-Informed consent is required. Please document on the request form or electronic order that a copy is on file. An Informed Consent for Genetic Testing (T576) is available in Special Instructions.

Useful For

Identifying individuals with genetic variants in DPYD who are at increased risk of toxicity when prescribed 5-fluorouracil (5-FU) or capecitabine chemotherapy treatment

Method Name

Real-Time Polymerase Chain Reaction (PCR) with Allelic Discrimination Analysis

Reporting Name

DPYD Genotype

Specimen Type


Specimen Minimum Volume

Blood: 0.4 mL
Saliva: 1 swab

Specimen Stability Information

Specimen Type Temperature Time
Varies Varies

Clinical Information

5-Fluorouracil (5-FU) and its orally administered prodrug, capecitabine, are fluoropyrimidine-based chemotherapeutic agents that are widely used for the treatment of colorectal cancer and other solid tumors.


The dihydropyrimidine dehydrogenase (DPYD) gene encodes the rate-limiting enzyme for fluoropyrimidine catabolism and eliminates over 80% of administered 5-FU. Dihydropyrimidine dehydrogenase (DPYD) activity is subject to wide variability, mainly due to genetic variation. This results in a broad range of enzymatic deficiency from partial (3%-5% of population) to complete loss (0.2% of population) of enzyme activity.(2,3) Patients who are deficient in DPYD are at an increased risk for side effects and toxicity when undergoing 5-FU treatment.(4) In addition, pathogenic homozygous or compound heterozygous variants within DPYD are associated with dihydropyrimidine dehydrogenase (DPD) deficiency. DPD deficiency shows large phenotypic variability, ranging from no symptoms to a convulsive disorder with motor and mental retardation.


The following table displays the DPYD variants detected by this assay, the corresponding star allele, and the effect on DPYD enzyme activity. Other or novel variations, besides those listed here, may also impact fluoropyrimidine-related side effects and tumor response.


 DPYD Allele

cDNA Nucleotide Change

Effect on Enzyme Activity


None (wild type)

Normal activity



No activity



No activity



Probable reduced activity



Variant of unknown significance



Probable reduced  activity



Probable reduced activity



No activity



Reduced activity



Reduced activity



Probable reduced activity

Reference Values

An interpretive report will be provided.


An interpretive report will be provided. 


For additional information regarding pharmacogenomic genes and their associated drugs, see Pharmacogenomics Associations Tables in Special Instructions. This resource also includes information regarding enzyme inhibitors and inducers, as well as potential alternate drug choices.

Clinical Reference

1. Online Mendelian Inheritance in Man: Dihydropyrimidine dehydrogenase deficiency. #274270. Updated 4/18/2012. Available at

2. Caudle KE, Thorn CF, Klein TE, et al: Clinical Pharmacogenetics Implementation Consortium guidelines for dihydropyrimidine dehydrogenase genotype and fluoropyrimidine dosing. Clin Pharmacol Ther 2013;94(6):640-645

3. Morel A, Boisdron-Celle M, Fey L, et al: Clinical relevance of different dihyropyrimidine dehydrogenase gene single nucleotide polymorphisms on 5-fluorouracil tolerance. Mol Cancer Ther 2006 Nov;5(11):2895-2904

4. FDA Table of Pharmacogenomic Biomarkers in Drug Labeling. Accessed June 2017. Available at

5. Offer SM, Fossum CC, Wegner NJ, et al: Comparative functional analysis of DPYD variants of potential clinical relevance to dihydropyrimidine dehydrogenase activity. Cancer Res 2014;74(9):2545-2554

Day(s) and Time(s) Performed

Monday through Friday; 8 a.m.

Analytic Time

3 days (Not reported on Saturday or Sunday)

Test Classification

This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.

CPT Code Information


LOINC Code Information

Test ID Test Order Name Order LOINC Value
DPYDV DPYD Genotype In Process


Result ID Test Result Name Result LOINC Value
BA0148 DPYD Predicted Toxicity Risk In Process
BA0149 DPYD Result Details In Process
BA0153 Interpretation In Process
BA0154 Additional Information 48767-8
BA0209 Method 49549-9
BA0210 Disclaimer 62364-5
BA0155 Reviewed by In Process
Mayo Medical Laboratories | Genetics and Pharmacogenomics Catalog Additional Information: