Defects in DPYD are the cause of dihydropyrimidine dehydrogenase deficiency (DPYD deficiency) [MIM:274270]; also known as hereditary thymine-uraciluria or familial pyrimidinemia. DPYD deficiency is a disease 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. This reaction includes stomatitis, Leukopenia, thrombocytopenia, hair loss, diarrhea, fever, marked weight loss, cerebellar ataxia, and neurologic symptoms, progressing to semicoma.
Belongs to the dihydropyrimidine dehydrogenase family. Contains 3 4Fe-4S ferredoxin-type domains.