DPD deficiency

We offer two pharmacogenomic tests to identify genetic variants associated with the metabolism of chemotherapy drugs in the fluoropyrimidine drug class, such as 5-fluorouracil and capecitabine. This testing specifically targets the DPYD gene, which plays a crucial role in the breakdown of these medications in the body. By analyzing specific variants within the DPYD gene, physicians and other healthcare professionals can assess a patient's risk of adverse reactions to these chemotherapy drugs, including severe fluoropyrimidine-induced toxicity and potentially life-threatening outcomes. In addition, pathogenic homozygous or compound heterozygous variants within DPYD are associated with dihydropyrimidine dehydrogenase (DPD) deficiency, a rare condition in which patients may experience no symptoms at all or something as severe as a convulsive disorder with motor and intellectual disabilities.

Genotype testing (Mayo ID: DPYDQ) is used for the assessment of common variants associated with DPYD deficiency. Full sequencing (Mayo ID: DPYDZ) is used based on patient or physician preference or when there is suspicion of rare or novel variants. Full sequencing also can be used when the patient's phenotype does not align with expected genotype results or for patients from ancestral populations that have not been genetically well-characterized.

Key testing

• DPYDQ | Dihydropyrimidine Dehydrogenase Genotype, Varies
  • Identifies individuals with common genetic variants in DPYD to anticipate increased risk of toxicity when prescribed 5-fluorouracil or capecitabine chemotherapy treatment.
• DPYDZ | Dihydropyrimidine Dehydrogenase, DPYD Full Gene Sequencing, Varies
  • Identifies individuals with any genetic variant in DPYD to anticipate increased risk of toxicity when considering 5-fluorouracil and capecitabine chemotherapy treatment.
  • Finds common and rare variants not included in the targeted genotyping assay associated with decreased or absent dihydropyrimidine dehydrogenase (DPD) enzyme activity in individuals with suspected DPD deficiency.