Summary & Overview
CPT 0231U: Genomic Unity® CACNA1A Analysis
CPT code 0231U designates the Genomic Unity® CACNA1A Analysis, a proprietary laboratory assay using PCR-free whole genome sequencing to evaluate the CACNA1A gene for disease-associated variants. As a PLA code tied to a single manufacturer, this code identifies a specific, high-complexity molecular diagnostic service for neurologic indications such as ataxia, familial hemiplegic migraine, and infantile epileptic encephalopathy. Nationally, PLA codes like 0231U matter because they standardize billing for unique commercial tests and influence access, coding transparency, and payer coverage practices across commercial and public programs.
Key payers covered in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise briefing on clinical context and intended use, typical sites of service, and the role of PLA coding in lab test identification. The publication also summarizes what to expect in payer engagement and benchmarking discussions, highlights policy considerations relevant to proprietary genetic tests, and provides the clinical framing necessary for coding, claims submission, and utilization review. Data not available in the input is noted where applicable.
Billing Code Overview
CPT code 0231U is a Proprietary Laboratory Analyses (PLA) code for the Genomic Unity® CACNA1A Analysis produced by Variantyx Inc. The test evaluates the CACNA1A gene (calcium voltage–gated channel subunit alpha1 A) for variants associated with conditions such as certain ataxias, familial hemiplegic migraine, and infantile epileptic encephalopathy. The assay is performed on a blood or saliva specimen and uses a PCR-free whole genome sequencing (WGS) platform with algorithmic data analysis to detect sequence variants in the target gene.
Service type: Laboratory — genetic sequencing / molecular diagnostic test
Typical site of service: Clinical laboratory or reference genetic testing laboratory
Clinical & Coding Specifications
Clinical Context
A 7-year-old child with episodes of progressive gait instability, episodic ataxia, and brief hemiplegic migraine presents to a pediatric neurology clinic. The neurologist documents a family history of similar episodic neurological events and progressive coordination decline. After neurologic examination and brain MRI that are nondiagnostic, the clinician orders a targeted genetic test to evaluate the CACNA1A gene. A blood or saliva specimen is collected in clinic or at a phlebotomy lab and sent to Variantyx Inc. for the Genomic Unity® CACNA1A Analysis reported with 0231U. The laboratory performs PCR-free whole genome sequencing and algorithmic analysis focused on the CACNA1A gene, interprets pathogenic and likely pathogenic variants, and issues a clinical report. The final report is reviewed by the ordering neurologist to confirm diagnosis such as episodic ataxia type 2, familial hemiplegic migraine, or CACNA1A-related epileptic encephalopathy, and to guide genetic counseling and family testing. Typical sites of service include outpatient neurology clinics, pediatric specialty clinics, and outpatient specimen collection centers. The service type is a proprietary laboratory genomic analysis (Proprietary Laboratory Analysis, PLA) performed by a specialized reference laboratory.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
26 | Professional component | Use when billing only the laboratory professional interpretation separate from the technical test if applicable and payer requires split billing. |