Summary & Overview

CPT 0031U: Cytochrome P450 1A2 Genotype, Mayo Clinic

CPT code 0031U designates a Proprietary Laboratory Analyses (PLA) test: the Cytochrome P450 1A2 Genotype developed by the Mayo Clinic. As a PLA code, it identifies a single, manufacturer- or laboratory-specific genetic assay that provides genotype information about the CYP1A2 enzyme, which can influence drug metabolism. Nationally, PLA codes like 0031U matter because they standardize billing for novel and proprietary molecular diagnostics, enabling clearer claims processing and payer evaluation for precision medicine services.

Key payers covered in this analysis include Aetna, Blue Cross Blue Shield, Cigna, UnitedHealthcare, and Medicare. Readers will find an explanation of what the code represents, the clinical context for a CYP1A2 genotype test, typical service setting and service type, and an outline of payer coverage considerations. The publication also summarizes available benchmarks and policy-relevant updates where provided, and highlights implications for clinical laboratories and billing workflows.

This executive summary presents the code’s purpose, its role in genetic testing reimbursement, and what stakeholders can expect to learn about billing classification, payer engagement, and operational impacts of adopting a PLA-coded laboratory assay.

AetnaBlue Cross Blue ShieldCignaUnitedHealthcareMedicare0031UCPTProprietary Laboratory AnalysesGenetic TestingCYP1A2Molecular DiagnosticsLaboratory BillingPharmacogenomics

Billing Code Overview

CPT code 0031U is a Proprietary Laboratory Analyses (PLA) code that describes a single, manufacturer- or laboratory-specific test: the Cytochrome P450 1A2 Genotype performed by the Mayo Clinic. The service type is a genetic/genomic laboratory test that reports genotype information for the CYP1A2 enzyme. The typical site of service is a clinical laboratory or reference laboratory setting where specialized molecular diagnostics are performed.

Data not available in the input.

Clinical & Coding Specifications

Clinical Context

A 52-year-old patient with a history of variable response to caffeine and reports of adverse effects with certain antidepressants is referred by their primary care physician to precision medicine services at an academic medical center. The clinician orders the Cytochrome P450 1A2 genotyping test (0031U) to evaluate genetic variants affecting CYP1A2 enzyme activity. A phlebotomy appointment is scheduled at the hospital outpatient laboratory; a blood sample is collected using standard specimen handling and sent to the Mayo Clinic laboratory performing the proprietary test. Results reporting includes genotype (e.g., *1A/*1F) and inferred metabolizer status with a laboratory-provided interpretation. The ordering clinician integrates the genotype report into medication selection and dosing decisions for drugs metabolized primarily by CYP1A2 (for example certain antidepressants, antipsychotics, and stimulants) and documents the test result in the electronic health record.

Coding Specifications

Modifier	Description	When to Use
`26`	Professional component	Use when billing only the professional interpretation component separate from the technical laboratory processing, if applicable.
`TC`

Taxonomy Code	Specialty	Notes
207Q00000X	Clinical Geneticist	Specialists who may order and interpret pharmacogenomic testing.
207L00000X	Clinical Laboratory Geneticist	Laboratory directors or specialists overseeing genetic testing.
208D00000X	Family Medicine	Primary care clinicians who commonly order pharmacogenomic testing for medication management.
207P00000X	Clinical Pharmacology	Pharmacists or pharmacologists involved in medication selection and dosing informed by genotype.
208000000X	Internal Medicine	Internists who integrate genotype data into chronic disease medication management.

Related Diagnoses

ICD-10 Code	Description	Clinical Relevance
`G47.00`	Insomnia, unspecified	CYP1A2 variants can affect response to stimulant or sedating medications prescribed for sleep disorders.
`F32.9`	Major depressive disorder, single episode, unspecified	Antidepressant selection and dosing can be influenced by CYP1A2 genotype for agents metabolized by this enzyme.
`F32.8`	Other depressive episodes	Genetic testing can inform drug choice in depressive disorders when metabolism is a concern.
`F41.1`	Generalized anxiety disorder	Medications metabolized by CYP1A2 may be considered for anxiety management; genotype can guide therapy.
`G47.3`	Sleep apnea (obstructive and central)	Relevant when stimulant therapy or certain psychotropic medications are considered and metabolism impact is assessed.

Related CPT Codes

CPT Code	Description	Relationship to This Procedure
`80053`	Comprehensive metabolic panel	Common baseline laboratory testing performed at the same visit for overall clinical assessment before or concurrent with genetic testing.
`36415`	Collection of venous blood by venipuncture	Specimen collection code frequently billed when a blood sample is collected for CYP1A2 genotyping.
`81379`	Pharmacogenomic testing (eg, multiple gene variants)	Other pharmacogenomic panel codes that may be ordered alongside or instead of a single-gene PLA; used when broader testing is performed.
`88271`	Molecular cytogenetics; fluorescence in situ hybridization (FISH), probe specific - technical component	Example of a molecular diagnostic laboratory code that may appear on the same lab bill; not specific to CYP1A2 but related to molecular testing workflows.
`99000`	Handling and/or conveyance of specimen for transfer from the physician's office to a laboratory	Used when the office arranges specimen transport to the reference laboratory performing the proprietary test.