Mondo Description Dihydropyrimidine dehydrogenase (DPD) deficiency isaconditionin which the body cannot break down the nucleotides thymine and uracil. DPD deficiency can have a wide range of severity; some individuals may have various neurological problems, while others have no signsand symptoms. Signs and symptoms in severely affected individuals begin in infancy and may include seizures, intellectual disability, microcephaly, increased muscle tone (hypertonia), delayed motor skills, and autistic behavior. All individuals with the condition, regardless of the presence or severity of symptoms, are at risk for severe, toxic reactions to drugs called fluoropyrimidines which are used to treat cancer. Individuals with no symptoms may be diagnosed only by laboratory testing or after exposure to fluoropyrimidines. DPD deficiency is caused by mutations in the DPYD gene and is inherited in an autosomal recessive manner.

Uniprot Description A metabolic disorder with large phenotypic variability, ranging from no symptoms to a convulsive disorder with motor and mental retardation. It is characterized by persistent urinary excretion of excessive amounts of uracil, thymine and 5-hydroxymethyluracil. Patients suffering from this disease show a severe reaction to the anticancer drug 5-fluorouracil.

Disease Ontology Description A purine-pyrimidine metabolic disorder that is an autosomal recessive metabolic disorder in which there is absent or significantly decreased activity of dihydropyrimidine dehydrogenase, an enzyme involved in the metabolism of uracil and thymine.