Your browser does not support javascript:   Search for gard hereSearch for news-and-events here.


Genetic and Rare Diseases Information Center (GARD)

Print friendly version

Dihydropyrimidine dehydrogenase deficiency

Other Names for this Disease
  • DPD deficiency
  • Familial pyrimidinemia
  • Hereditary thymine-uraciluria
See Disclaimer regarding information on this site. Some links on this page may take you to organizations outside of the National Institutes of Health.


Newline Maker

What causes dihydropyrimidine dehydrogenase (DPD) deficiency?

DPD deficiency is caused by mutations in the DPYD gene. This gene provides instructions for making an enzyme called dihydropyrimidine dehydrogenase (DPD), which is involved in the breakdown of molecules called uracil and thymine. Uracil and thymine are building blocks of DNA, RNA, and molecules that serve as energy sources in cells.

Mutations in the DPYD gene result in deficiencies (to various degrees) of functional DPD, interfering with the breakdown of uracil and thymine in cells. This results in excessive amounts of uracil and thymine in the blood, urine, and the fluid that surrounds the brain and spinal cord. It is currently poorly understood exactly how this cascade of events causes the signs and symptoms of the condition.[1]
Last updated: 8/20/2012

  1. Dihydropyrimidine dehydrogenase deficiency. Genetics Home Reference. November 2011; Accessed 11/28/2012.