5-Fluorouracil 5-FU Toxicity and Chemotherapeutic Response DPYD Variants Test
Understanding 5-FU Chemotherapy and Genetic Testing
5-Fluorouracil (5-FU) is one of the most widely used chemotherapy drugs for treating various cancers, including colorectal, breast, head and neck, and gastrointestinal cancers. However, approximately 3-5% of patients carry genetic variations in the DPYD gene that significantly impact their ability to metabolize this medication safely. The DPYD gene encodes the enzyme dihydropyrimidine dehydrogenase, which is responsible for breaking down 5-FU in the body. When this enzyme doesn’t function properly due to genetic variations, patients can experience severe, potentially life-threatening toxicity from standard chemotherapy doses.
What This Test Measures and Detects
Our comprehensive genetic test specifically analyzes key variations in the DPYD gene using advanced Sanger Sequencing technology. The test identifies:
- DPYD*2A (c.1905+1G>A) – The most common and clinically significant variant
- DPYD*13 (c.1679T>G) – Associated with reduced enzyme activity
- c.2846A>T – Another important variant affecting drug metabolism
- c.1129-5923C>G – HapB3 variant impacting enzyme function
These genetic markers help predict how effectively your body can process 5-FU chemotherapy, allowing for personalized dosing strategies that maximize treatment effectiveness while minimizing dangerous side effects.
Who Should Consider This Genetic Test
This test is particularly important for:
- Patients scheduled to receive 5-FU or capecitabine-based chemotherapy
- Individuals with a family history of severe reactions to chemotherapy
- Patients experiencing unexpected toxicity during 5-FU treatment
- Oncologists seeking to personalize chemotherapy regimens
- Individuals of European descent, where DPYD variants are more common
Early genetic screening can prevent severe complications including mucositis, diarrhea, neutropenia, neurotoxicity, and hand-foot syndrome.
Benefits of DPYD Genetic Testing
Undergoing DPYD variant testing provides numerous advantages:
- Personalized Treatment: Enables dose adjustments based on your genetic profile
- Reduced Toxicity Risk: Prevents severe and potentially fatal side effects
- Improved Treatment Outcomes: Maintains chemotherapy efficacy while enhancing safety
- Cost-Effective Care: Reduces hospitalizations and supportive care costs
- Informed Decision Making: Empowers patients and providers with crucial genetic information
Understanding Your Test Results
Your test results will fall into one of three categories:
- Normal Metabolizer: No significant DPYD variants detected – standard 5-FU dosing is typically appropriate
- Intermediate Metabolizer: One variant detected – may require 50-75% dose reduction and careful monitoring
- Poor Metabolizer: Two variants or high-risk single variants detected – requires significant dose reduction (25-50%) or alternative treatment options
Your oncologist will interpret these results in the context of your overall health and cancer treatment plan to determine the safest and most effective chemotherapy approach.
Test Pricing and Details
| Test Component | Details |
|---|---|
| Test Name | 5-Fluorouracil 5-FU Toxicity and Chemotherapeutic Response DPYD Variants |
| Discount Price | $132 USD |
| Regular Price | $176 USD |
| Turnaround Time | 3-4 days |
| Sample Type | Peripheral Blood |
| Test Components | EDTA Vacutainer (2ml) |
| Testing Method | Sanger Sequencing |
Nationwide Availability and Booking
We have testing facilities conveniently located across the United States, including major metropolitan areas such as New York, Los Angeles, Chicago, Houston, Phoenix, Philadelphia, San Antonio, San Diego, Dallas, and San Jose. Our state-of-the-art laboratories ensure accurate and timely results to support your cancer treatment journey.
Important Pre-Test Information: This test requires a doctor’s prescription for chemotherapy planning. Prescription requirements do not apply for surgical planning, pregnancy-related testing, or international travel purposes.
Take Control of Your Chemotherapy Safety
Don’t leave your chemotherapy safety to chance. Our DPYD genetic testing provides the critical information needed to personalize your cancer treatment and minimize risks. With rapid 3-4 day turnaround and comprehensive analysis, you can make informed decisions about your care with confidence.
Book your test today or call our genetic counseling team at +1(267) 388-9828 to discuss how DPYD testing can optimize your chemotherapy experience and protect your health during cancer treatment.

