Dihydropyrimidine dehydrogenase deficiency

Dihydropyrimidine dehydrogenase deficiency is an autosomal recessivemetabolic disorder in which there is absent or significantly decreased activity of dihydropyrimidine dehydrogenase, an enzyme involved in the metabolism of uracil and thymine. Dihydropyrimidine dehydrogenase deficiency is an autosomal recessivemetabolic disorder in which there is absent or significantly decreased activity of dihydropyrimidine dehydrogenase, an enzyme involved in the metabolism of uracil and thymine. Individuals with this condition may develop life-threatening toxicity following exposure to 5-fluorouracil (5-FU), a chemotherapy drug that is used in the treatment of cancer. Beside 5-FU, widely prescribed oral fluoropyrimidine capecitabine (Xeloda) could put DPD-deficient patients at risk of experiencing severe or lethal toxicities as well. DPD deficiency is inherited in an autosomal recessive manner. This means the defective gene responsible for the disorder is located on an autosome, and two copies of the defective gene (one inherited from each parent) are required in order to be born with the disorder. The parents of an individual with an autosomal recessive disorder both carry one copy of the defective gene, but usually do not experience any signs or symptoms of the disorder.