Summary & Overview
CPT 81231: CYP3A5 Genetic Variant Analysis
CPT code 81231 describes a laboratory molecular diagnostic assay for detection of common variants in the CYP3A5 gene (e.g., *2, *3, *4, *5, *6, *7). This pharmacogenetic test informs clinicians and pharmacists about CYP3A5 enzyme polymorphisms that can affect drug metabolism, dosing, and risk of adverse effects for multiple medications nationally. As precision medicine expands, standardized reporting and coverage policies for pharmacogenomic tests like CPT code 81231 are increasingly relevant to patient safety and medication management.
Key payers covered in this overview include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise review of what the code represents clinically, typical sites and service types, and the payer landscape addressed in the analysis. The publication presents benchmarks and coverage considerations, clinical context for pharmacogenetic testing, and operational notes for laboratories and billing teams. Policy updates and payer-specific coverage rules are summarized where available; if specific payer policy data are not provided, the text notes that input data are not available. The focus is national in scope and centers on the clinical and billing implications of performing CYP3A5 variant analysis under CPT code 81231.
Billing Code Overview
CPT code 81231 reports laboratory testing that analyzes common variants of the cytochrome P450 family 3 subfamily A member 5 gene (CYP3A5), including alleles such as *2, *3, *4, *5, *6, and *7. The procedure describes the technical laboratory analysis performed by a lab analyst to detect these genetic variants.
Service type: Genetic testing / molecular diagnostic assay
Typical site of service: Clinical laboratory or molecular diagnostics laboratory
Data not available in the input.
Clinical & Coding Specifications
Clinical Context
A 52-year-old patient with a history of hypertension and hyperlipidemia is being considered for initiation of tacrolimus for an autoimmune condition and for optimization of dosing for a calcineurin inhibitor following recent renal transplant. The ordering clinician requests pharmacogenetic testing for CYP3A5 common alleles to determine whether the patient is an expressor or non‑expressor of CYP3A5, which affects metabolism of tacrolimus and other drugs. A peripheral blood specimen or buccal swab is collected in clinic and sent to the molecular diagnostics laboratory. The laboratory performs CPT 81231 to detect common CYP3A5 variants (for example *2, *3, *4, *5, *6, *7). The lab analyst runs targeted genotyping assays, interprets variant calls, and reports metabolizer status to the ordering provider. Typical site of service is an outpatient clinic or hospital-affiliated molecular diagnostics laboratory that receives specimens from ambulatory clinics, transplant centers, or inpatient services. The clinical workflow includes: specimen collection and logging, DNA extraction, targeted variant analysis by PCR-based or sequencing methods, analytic validation and quality control, result interpretation, and issuance of a molecular genetics report incorporated into the electronic medical record for use in drug dosing decisions.
Coding Specifications
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