As a fluoropyrimidine, several genes (notably the DPYD and TPMT genes) are known to harbor nonfunctional alleles that predispose individuals administered tegafur to potentially severe or even fatal toxicity.
|Genotype/Genoset||Diplotype||Gene||Drug Use/Category/Class||Medical Field||Summary||Descriptive Sentence|
|gs313||Normal metabolizer||DPYD||Chemotherapeutic||Oncology||Normal Response Expected||You do not appear to carry any DPYD mutations linked to adverse side effects from tegafur use.|
|gs312||Intermediate Metabolizer||DPYD||Chemotherapeutic||Oncology||Consider Half-Dose and/or Pharmacokinetic Studies||You carry a nonfunctional DPYD allele that increases your risk for a toxicity upon tegafur administration; consider starting at half-dose and/or doing pharmacokinetic studies.|
|gs306||Poor Metabolizer||DPYD||Chemotherapeutic||Oncology||Avoid 5-FU; use an alternative drug||You may be at very high risk for severe toxicity from tegafur administration; all major drug regulatory agencies recommend you select a non-fluoropyrimidine alternative chemotherapeutic.|