Test Code MISC2MAYOU1A1V UDP-Glucuronosyl Transferase 1A1 TA Repeat Genotype, UGT1A1, Varies
Advisory Information
This test does not detect or report variants other than the *1 (TA6), *28 (TA7), *36 (TA5), and *6 (c.211G->A) alleles. Individuals with a *37 (TA8) allele cannot be distinguished from *28 (TA7) will be assigned *28 (TA7) by this methodology. Numerous variants outside of the TA repeat region have been described that impair UGT1A1 activity. Sequencing of the full gene is also available for detection of variants outside of the TA repeat region.
-Order UGTFG / UDP-Glucuronosyl Transferase 1A1 (UGT1A1), Full Gene Sequencing.
Specimen Required
Multiple genotype tests can be performed on a single specimen after a single extraction. See Multiple Genotype Test List in Special Instructions for a list of tests that can be ordered together.
Submit only 1 of the following specimens:
Specimen Type: Whole blood
Container/Tube: Lavender top (EDTA)
Specimen Volume: 3 mL
Collection Instructions:
1. Invert several times to mix blood.
2. Send specimen in original tube.
Specimen Stability Information: Ambient (preferred)/Refrigerated
Specimen Type: Saliva
Patient Preparation: Patient should not eat, drink, smoke, or chew gum 30 minutes prior to collection.
Supplies: DNA Saliva Collection Kit (T786)
Container/Tube: Saliva Swab Collection Kit
Specimen Volume: 1 swab
Collection Instructions: Collect and send specimen per kit instructions.
Specimen Stability Information: Ambient
Specimen Type: DNA
Container/Tube: 2 mL screw top tube
Specimen Volume: 100 mcL (microliters)
Collection Instructions:
1. The preferred volume is 100 mcL at a concentration of 50 ng/mcL.
2. Include concentration and volume on tube.
Specimen Stability Information: Frozen (preferred)/Ambient/Refrigerated
Forms
1. New York Clients-Informed consent is required. Document on the request form or electronic order that a copy is on file. The following documents are available in Special Instructions:
-Informed Consent for Genetic Testing (T576)
-Informed Consent for Genetic Testing-Spanish (T826)
2. If not ordering electronically, complete, print, and send a Therapeutics Test Request (T831) form with the specimen.
Secondary ID
97400Useful For
Identifying individuals who are at increased risk of adverse drug reactions with drugs that are metabolized by UGT1A1; especially irinotecan, but also including atazanavir, nilotinib, pazopanib, and belinostat
Identifying individuals with Gilbert syndrome due to the presence of homozygous UGT1A1*6 (c.211G->A) allele, TA7, homozygous TA8, or compound heterozygous *6, TA7 or TA8
Identifying individuals who are carriers of Gilbert syndrome due to the presence of heterozygous TA7 or TA8
Testing Algorithm
See UGT1A1 Test-Ordering Algorithm in Special Instructions.
Special Instructions
Method Name
Real-Time Polymerase Chain Reaction (PCR) with Allelic Discrimination Analysis
Reporting Name
UGT1A1 GenotypeSpecimen Type
VariesSpecimen Minimum Volume
Blood: 0.4 mL
Saliva: 1 swab
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Varies | Varies |
Reject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability. |
Reference Values
An interpretive report will be provided.
Day(s) and Time(s) Performed
Monday through Friday; 8 a.m.
Performing Laboratory

Test Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.CPT Code Information
81350-UGT1A1 (UDP glucuronosyltransferase 1 family, polypeptide AI) (eg, irinotecan metabolism), gene analysis, common variants (eg, *28, *36, *37)
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
U1A1V | UGT1A1 Genotype | 34509-0 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
BA0143 | UGT1A1 Genotype | 93845-6 |
BA0144 | UGT1A1 Phenotype | 79718-3 |
BA0145 | Interpretation | 69047-9 |
BA0146 | Additional Information | 48767-8 |
BA0207 | Method | 49549-9 |
BA0208 | Disclaimer | 62364-5 |
BA0147 | Reviewed by | 18771-6 |