Crigler-Najjar syndrome testing (UGT1A1)
GTR Test Accession: Help GTR000328355.3
Last updated in GTR: 2020-08-10
Last annual review date for the lab: 2023-07-18 LinkOut
At a Glance
Diagnosis; Monitoring; Mutation Confirmation; ...
Crigler-Najjar syndrome
Genes (1): Help
UGT1A1 (2q37.1)
Molecular Genetics - Deletion/duplication analysis: Next-Generation (NGS)/Massively parallel sequencing (MPS); ...
The target population is patients suspected of having a diagnosis …
Mutations in the UDP-Glycosyltransferase 1 Family, Polypeptide A1 (UGT1A1) gene …
Not provided
Ordering Information
Offered by: Help
Specimen Source: Help
  • Amniocytes
  • Amniotic fluid
  • Buccal swab
  • Cell culture
  • Chorionic villi
  • Cord blood
  • Fetal blood
  • Fibroblasts
  • Frozen tissue
  • Isolated DNA
  • Peripheral (whole) blood
  • Product of conception (POC)
  • Saliva
  • View specimen requirements
Who can order: Help
  • Genetic Counselor
  • Health Care Provider
  • Licensed Physician
  • Nurse Practitioner
  • Physician Assistant
  • Registered Nurse
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
Clinical Testing/Confirmation of Mutations Identified Previously
Confirmation of research findings
Custom Sequence Analysis
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: 2
Method Category Help
Test method Help
Instrument *
Deletion/duplication analysis
Next-Generation (NGS)/Massively parallel sequencing (MPS)
Sequence analysis of the entire coding region
Next-Generation (NGS)/Massively parallel sequencing (MPS)
* Instrument: Not provided
Clinical Information
Test purpose: Help
Diagnosis; Monitoring; Mutation Confirmation; Pre-symptomatic; Risk Assessment; Screening
Clinical validity: Help
Mutations in the UDP-Glycosyltransferase 1 Family, Polypeptide A1 (UGT1A1) gene [OMIM #191740] have been identified in patients with CN. UGT1A1 encodes the bilirubin uridine diphospho-glucoronosyltransferase (B-UGT) which is the enzyme that catalyzes the glucuronidation of bilirubin .CN-1 is due to the total absence of hepatic B-UGT activity, and B-UGT activity … View more
View citations (1)
  • Petit, FM., et al. Large deletion in UGT1A1 gene encompassing the promoter and the exon 1 responsible for Crigler-Najjar type 1 syndrome. Haematologica. 2008 93(10): 1590-1 Zmetakova, I., et al. Identification of the deletions in the UGT1a1 gene of the patients with Crigler-Najjar syndrome type 1 from Slovakia. Gen. Physiol. Biophys. 2007. 26:306-310. Koiwai, O., et al., Crigler-Najjar syndrome type II is inherited both as a dominant and as a recessive trait. Human Molecular Genetics. 1996. 5(5):645-647. Kaplan, M, and C. Hammerman. Bilirubin and the Genome: The Hereditary Basis of Unconjugated Neonatal Hyperbilirubinemia. Current Pharmacogenomics. 2005. 3:21-42.
Target population: Help
The target population is patients suspected of having a diagnosis of Crigler-Najjer syndrome.
Variant Interpretation:
What is the protocol for interpreting a variation as a VUS? Help
Variants will be 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%
Assay limitations: Help
Only the coding and immediate flanking regions of the UGT1A1 gene and the immediate 5' untranslated region of the UGT1A1 gene were analyzed. Changes in other non-coding regions will not be detected by our assay. DNA sequencing detects 99-100% of nucleotide base alterations, small deletions and insertions. Our CNV detection … View more
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: FDA exercises enforcement discretion
Additional Information

IMPORTANT NOTE: NIH does not independently verify information submitted to GTR; it relies on submitters to provide information that is accurate and not misleading. NIH makes no endorsements of tests or laboratories listed in GTR. GTR is not a substitute for medical advice. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.