NUDT15 Genotyping

Casandra

Casandra Test Code AR45097Version 1 (DRAFT)

Performing Lab

Lab ARUP LaboratoriesLab Test ID 3017373CPT Code 81306

Also known as: NUDT15GENO

Clinical Use

Order Test

Use

The NUDT15 Genotyping test is utilized to assess the genetic risk for severe myelosuppression with standard dosing of thiopurine drugs in individuals who are considered for such therapy or have experienced adverse reactions to thiopurine drugs. This is critical as variants in the NUDT15 gene can lead to the accumulation of cytotoxic metabolites, increasing the risk of drug-related toxicity. Understanding a patient's genotype can guide the initiation and dosing of thiopurine therapy, potentially necessitating dose adjustments based on the predicted metabolizer status.

Special Instructions

Counseling and informed consent are recommended for genetic testing. New York patients are required to submit an Informed Consent for Genetic Testing. Use of this test is guided by the CPIC guidelines, and it involves assessing risks associated with thiopurine drugs. The result interpretation should be done in consultation with clinical guidelines and physician recommendations.

Limitations

This test will only detect targeted NUDT15 variants and may not predict actual enzyme activity fully. Factors such as additional genetic and non-genetic variables might affect thiopurine metabolism, which are not evaluated by this test. Genotyping may show donor status in patients with recent stem cell or bone marrow transplants. Only the specified NUDT15 variants are detected, and testing does not replace clinical monitoring. Diagnostic inaccuracies can arise from rare genetic variations. This test is not a substitute for therapeutic drug monitoring or clinical oversight.

Test Details

New York Approved

Methodology

PCR-based (PCR)

Biomarkers

NUDT15

Gene

Variant Detection • Mutation • Categorical (e.g., Positive / Negative / Indeterminate)

LOINC Codes

Result Codes

93194-9

Result Turnaround Time

5-10 days

Specimen

Whole Blood

Volume

3 mL

Minimum Volume

1 mL

Container

Lavender (EDTA), pink (K2EDTA), or yellow (ACD solution A or B)

Storage Instructions

Refrigerated

Causes for Rejection

Plasma or serum; specimens collected in sodium heparin or lithium heparin; frozen specimens in glass collection tubes; frozen yellow (ACD solution A or B)