UGT1A1 genotyping for irinotecan dosing
GTR Test Accession: Help GTR000500148.3
Last updated in GTR: 2020-08-13
Last annual review date for the lab: 2023-07-18 LinkOut
At a Glance
Risk Assessment; Mutation Confirmation; Diagnosis; ...
Irinotecan response
Genes (1): Help
UGT1A1 (2q37.1)
Molecular Genetics - Targeted variant analysis: PCR electrophoresis, capillary gel
The target population is patients wishing to be screened for …
Irinotecan metabolism – Irinotecan is converted in the liver to …
Not provided
Ordering Information
Offered by: Help
Specimen Source: Help
  • Product of conception (POC)
  • Chorionic villi
  • Saliva
  • Peripheral (whole) blood
  • Fetal blood
  • Frozen tissue
  • Amniocytes
  • Amniotic fluid
  • Cell culture
  • Fibroblasts
  • Cord blood
  • Fresh tissue
  • Buccal swab
  • View specimen requirements
Who can order: Help
  • Genetic Counselor
  • Health Care Provider
  • Registered Nurse
  • Licensed Physician
  • Physician Assistant
  • Nurse Practitioner
CPT codes: Help
**AMA CPT codes notice
Contact Policy: Help
Laboratory can only accept contact from health care providers. Patients/families are encouraged to discuss genetic testing options with their health care provider.
How to Order: Help
All samples should be shipped via overnight delivery at room temperature.

No weekend or holiday deliveries.

Label each specimen with the patient’s name, date of birth and date sample collected.

Send specimens with complete requisition and consent form, otherwise, specimen processing may be delayed.
Order URL
Test service: Help
Confirmation of research findings
Custom Sequence Analysis
Clinical Testing/Confirmation of Mutations Identified Previously
Test additional service: Help
Custom Prenatal Testing
Custom mutation-specific/Carrier testing
Test development: Help
Test developed by laboratory (no manufacturer test name)
Informed consent required: Help
Pre-test genetic counseling required: Help
Decline to answer
Post-test genetic counseling required: Help
Decline to answer
Recommended fields not provided:
Conditions Help
Total conditions: 1
Condition/Phenotype Identifier
Test Targets
Genes Help
Total genes: 1
Gene Associated Condition Germline or Somatic Allele (Lab-provided) Variant in NCBI
Total methods: 1
Method Category Help
Test method Help
Instrument *
Targeted variant analysis
PCR electrophoresis, capillary gel
* Instrument: Not provided
Clinical Information
Test purpose: Help
Risk Assessment; Mutation Confirmation; Diagnosis; Monitoring; Screening; Pre-symptomatic
Clinical validity: Help
Irinotecan metabolism – Irinotecan is converted in the liver to its active metabolite, SN-38, which subsequently gets conjugated to its glucuronide, SN-38G that is excreted from the body. Decreased levels of glucuronidation results in elevated amounts of SN-38 that is responsible for the severe diarrhea and neutropenia phenotypes in patients. … View more
Target population: Help
The target population is patients wishing to be screened for irinotecan response.
Variant Interpretation:
What is the protocol for interpreting a variation as a VUS? Help
Variants are identified and evaluated using a custom collection of bioinformatic tools and comprehensively interpreted by our team of directors and genetic counselors.

Will the lab re-contact the ordering physician if variant interpretation changes? Help
Is research allowed on the sample after clinical testing is complete? Help
Recommended fields not provided:
Technical Information
Availability: Help
Tests performed
Entire test performed in-house
Analytical Validity: Help
Analytical Sensitivity 99-100% Accuracy 100% Precision 100%
Proficiency testing (PT):
Is proficiency testing performed for this test? Help

Method used for proficiency testing: Help
Formal PT program

PT Provider: Help
American College of Medical Genetics / College of American Pathologists, ACMG/CAP
Software used to interpret novel variations Help
A custom collection of bioinformatics tools

Laboratory's policy on reporting novel variations Help
The laboratory reports novel variations.
Recommended fields not provided:
Regulatory Approval
FDA Review: Help
Category: Not Applicable
Additional Information

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