INFINITI UGT1A1 Assay
Sample Type and Volume:
- UGT 1A1 is responsible for conjugating SN 38, the active metabolite of irinotecan HCl.
- UGT 1A1*28 genotype (heterozygous *1/*28 or wild type *28/*28) increases risk of irinotecan related toxicity due to a higher exposure to SN 38 in the liver.
- UGT 1A1*37 polymorphism also results in high levels of active metabolite SN 38, thus *37 also presents a risk for neutropenia.
- UGT 1A1*36 polymorphism enhances the metabolism of SN 38, thus *36 tolerate a higher irinotecan dosage
- Studies have shown that testing an individual for UGT1A1*28 polymorphism will allow the physician to determine the specific dosage of irinotecan per the individual
- This will reduce toxicity associated with the polymorphism, as well as the severity of the side effects of irinotecan HC1.
- Approximately 10% of the North American population inherits two copies of UGT1A1*28 and are at a much higher risk of having a toxic reaction to the drug interacation HC1.
How Long Will It Take For Oncologists To Embrace UGT1A1 Testing?” Diagnostic Testing and Technology Report. Feb. 2006. VI(6): 5-7
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- Kadakol A, Ghosh SS, Sappal BS, et al. (2000). "Genetic lesions of bilirubin uridine-diphosphoglucuronate glucuronosyltransferase (UGT1A1) causing Crigler-Najjar and Gilbert syndromes: correlation of genotype to phenotype.". Hum. Mutat. 16 (4): 297–306. doi:10.1002/1098-1004(200010)16:4<297::AID-HUMU2>3.0.CO;2-Z. PMID 11013440.