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GTR Home > Conditions/Phenotypes > Dihydropyrimidine dehydrogenase deficiency


Dihyropyrimidine dehydrogenase deficiency shows large phenotypic variability, ranging from no symptoms to a convulsive disorder with motor and mental retardation in homozygous patients. In addition, homozygous and heterozygous mutation carriers can develop severe toxicity after the administration of the antineoplastic drug 5-fluorouracil (5FU), which is also catabolized by the DPYD enzyme. This is an example of a pharmacogenetic disorder (Van Kuilenburg et al., 1999). Since there is no correlation between genotype and phenotype in DPD deficiency, it appears that the deficiency is a necessary, but not sufficient, prerequisite for the development of clinical abnormalities (Van Kuilenburg et al., 1999; Enns et al., 2004). [from OMIM]

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  • Also known as: DHP, DHPDHASE, DPD, DYPD, DPYD
    Summary: dihydropyrimidine dehydrogenase

Clinical features


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