Summary & Overview

CPT 0232U: Genomic Unity CSTB Analysis, PCR‑free Whole Genome Sequencing

CPT code 0232U designates the Genomic Unity® CSTB Analysis, a Proprietary Laboratory Analyses (PLA) test by Variantyx Inc. that uses PCR-free whole genome sequencing of blood or saliva to evaluate the cystatin B (CSTB) gene for variants linked to progressive myoclonic epilepsy type 1A (Unverricht–Lundborg syndrome). As a PLA code, 0232U maps to a single manufacturer-specific assay, which matters for coverage determination, billing consistency, and laboratory reimbursement nationally.

Key payers in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find national-level context about the code's clinical purpose, typical site of service, and implications for laboratory and payer interactions. The publication outlines benchmark considerations for PLA-coded tests, summarizes clinical context for CSTB sequencing, and highlights policy-relevant elements such as PLA coding implications for unique proprietary assays and the expected settings for specimen collection and laboratory processing.

Data not available in the input for associated taxonomies, ICD-10 diagnoses, related codes, and detailed payer coverage policies.

AetnaBlue Cross Blue ShieldCigna HealthUnitedHealthcareMedicare0232UCPTProprietary Laboratory Analyseswhole genome sequencingCSTBgenetic testingmolecular diagnosticslaboratory coding

Billing Code Overview

CPT code 0232U is a Proprietary Laboratory Analyses (PLA) code assigned to the Genomic Unity® CSTB Analysis manufactured by Variantyx Inc. The test evaluates the cystatin B (CSTB) gene for genetic variants associated with conditions such as progressive myoclonic epilepsy type 1A (Unverricht–Lundborg syndrome). The assay uses a blood or saliva specimen and is performed on a PCR-free whole genome sequencing (WGS) platform with algorithmic data analysis.

Service type: Genetic sequencing / molecular diagnostic testing

Typical site of service: Clinical laboratory (blood or saliva specimen collection in outpatient clinic, physician office, or specimen collection center; laboratory processing in a specialized molecular diagnostics lab)

Clinical & Coding Specifications

Clinical Context

A patient (adult or pediatric) with progressive myoclonic seizures or a family history of Unverricht–Lundborg syndrome presents to a neurologist or geneticist for diagnostic evaluation. The clinician documents refractory myoclonic epilepsy, action- and stimulus-sensitive myoclonus, cognitive decline, and/or early-onset generalized tonic–clonic seizures and orders a targeted genomic test. A blood or saliva specimen is collected in the outpatient clinic or infusion center and sent to Variantyx for the proprietary Genomic Unity® CSTB Analysis. The laboratory performs PCR-free whole genome sequencing (WGS) with algorithmic analysis focused on the CSTB gene to identify pathogenic variants, repeat expansions, or other alterations relevant to progressive myoclonic epilepsy type 1A. Results are returned to the ordering clinician for integration into clinical diagnosis, genetic counseling, family cascade testing, and treatment planning. Typical sites of service include outpatient physician offices, specialty neurology clinics, and commercial genetic testing laboratories; specimen collection may occur in-clinic or at a certified phlebotomy site.

Coding Specifications

Modifier	Description	When to Use
`00`	Default/Standard - no modifier	Used when no other modifier applies and the service is billed normally.
`22`	Increased procedural services	Rarely used; if laboratory documents substantially increased analytical complexity documented by the lab and payer allows modifier for PLA codes.
`26`	Professional component	Used when billing only the professional component for interpretation if separated from technical component.
`52`	Reduced services	Use if the test was partially performed or limited by specimen issues and payer accepts modifier on laboratory services.
`53`	Discontinued procedure	Applied if testing was started but discontinued for documented clinical reasons.
`62`	Two surgeons (or dual qualified providers)	Not typically used for laboratory PLA testing; included when two qualified providers share responsibility for interpretation in rare institutional workflows.
`78`	Unplanned return to operating/procedure room	Not applicable in most genetic testing workflows; reserved for completeness for cases involving procedure-related sequelae.
`80`	Assistant surgeon	Not applicable for laboratory testing; may apply to associated procedural services when an assistant is involved.
`AS`	Physician assistant, nurse practitioner, clinical nurse specialist services	Use when these providers order/interpret under permitted payer rules and their taxonomy is reported.

Taxonomy Code	Specialty	Notes
207RG0300X	Neurology	Neurologists commonly order and interpret results for epilepsy and myoclonus evaluation.
207K00000X	Medical Genetics	Clinical geneticists evaluate hereditary epilepsy syndromes and coordinate genetic counseling.
208D00000X	Clinical Pathology/Clinical Laboratory	Laboratory directors and molecular pathologists oversee testing quality and interpretation.
363L00000X	Clinical Molecular Genetics	Specialists in molecular diagnostics who perform or consult on WGS-based analyses.
207LP2900X	Pediatric Neurology	Pediatric neurologists manage early-onset progressive myoclonic epilepsy and order targeted genetic testing.

Related Diagnoses

ICD-10 Code	Description	Clinical Relevance
`G40.409`	Epilepsy, intractable, with status epilepticus, unspecified, not stated as refractory	Progressive myoclonic epilepsy may present with intractable seizures prompting targeted genetic testing.
`G40.309`	Generalized idiopathic epilepsy and epileptic syndromes with seizures, intractable	Genetic evaluation for syndromic causes such as Unverricht–Lundborg syndrome.
`G25.3`	Myoclonus	Myoclonus is a cardinal feature of progressive myoclonic epilepsy and is an indication for `CSTB` testing.
`R56.9`	Unspecified convulsions	Initial presentations with convulsions often lead to genetic investigation when etiology is unclear.
`F07.81`	Postconcussional syndrome (include cognitive decline codes as relevant)	Cognitive decline or neurocognitive symptoms accompanying myoclonus may prompt genomic testing.
`Z13.79`	Encounter for screening for other genetic and chromosomal anomalies	Used when ordered as part of a genetic evaluation or family screening for known familial variants.
`Z14.8`	Genetic carrier screening and counseling related codes	Used when ordering carrier or family cascade testing following identification of a pathogenic `CSTB` variant.

Related CPT Codes

CPT Code	Description	Relationship to This Procedure
`0232U`	Genomic Unity® CSTB Analysis (proprietary PLA)	Primary PLA code for the PCR-free WGS-based analysis of the `CSTB` gene; used to report the test performed by Variantyx.
`81479`	Unlisted molecular pathology procedure	May be used by other laboratories for non-proprietary or custom molecular analyses when no specific PLA code exists.
`0004U`	Whole genome sequencing, interpretive report (example PLA)	Other PLA-level WGS or genomic interpretation services may be ordered alongside or for broader genomic analysis beyond `CSTB`.
`81002`	Urinalysis, non-automated, without microscopy	Example ancillary specimen tests (billing depends on clinical context); not routinely paired but may appear in complex evaluations.
`36415`	Collection of venous blood by venipuncture	Performed at specimen collection for blood-based genomic testing; billed by the facility or phlebotomist as applicable.
`99000`	Handling and/or conveyance of specimen to a laboratory	Facility-specific or courier-related charges associated with transporting the blood or saliva specimen to the reference laboratory.