Summary & Overview

CPT 0335U: IriSight™ Prenatal Whole Genome Analysis — Proband

CPT code 0335U designates the IriSight™ Prenatal Analysis – Proband, a proprietary whole genome sequencing test from Variantyx Inc. performed on fetal samples to detect genetic variants linked to fetal or pregnancy clinical findings and rare heritable disorders. As a PLA code, 0335U applies exclusively to this single manufacturer's test, which has implications for coding accuracy, laboratory billing, and payer recognition nationally.

Key payers included in the analysis are Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise explanation of the test’s clinical purpose and service setting, the implications of PLA designation for reimbursement and prior authorization workflows, and what to expect when billing this code to major national payers.

This publication provides national-level benchmarks and policy context relevant to proprietary laboratory tests, outlines common payer considerations for coverage and claims processing, and summarizes clinical context for prenatal whole genome sequencing. Data not available in the input is noted where applicable.

AetnaBlue Cross Blue ShieldCigna HealthUnitedHealthcareMedicare0335UCPTProprietary Laboratory Analysesprenatal whole genome sequencingfetal genetic testinglaboratory billingvariant interpretationclinical geneticsdiagnostic testing

Billing Code Overview

CPT code 0335U is a Proprietary Laboratory Analyses (PLA) code for the IriSight™ Prenatal Analysis – Proband offered by Variantyx Inc. The test is a whole genome sequencing analysis performed on a fetal sample to identify genetic variants that may be related to clinical fetal or pregnancy symptoms or that could indicate rare heritable disorders.

Service type: Whole genome sequence analysis for prenatal/fetal genetic evaluation
Typical site of service: Clinical diagnostic laboratory processing fetal specimens (prenatal diagnostic setting)

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

Clinical & Coding Specifications

Clinical Context

A pregnant patient at 18–24 weeks gestation, referred by a maternal-fetal medicine specialist after an ultrasound identifies fetal structural anomalies or when there is a family history suggestive of a rare heritable disorder. A fetal sample (amniotic fluid via amniocentesis or chorionic villus sampling) is collected and sent to Variantyx Inc. for IriSight™ Prenatal Analysis – Proband reported under 0335U. The laboratory performs whole genome sequencing of the fetal sample to identify single-nucleotide variants, insertions/deletions, copy-number variants, and other genomic findings that may explain observed fetal or pregnancy symptoms. Results are returned to the ordering clinician with a diagnostic report that may include pathogenic, likely pathogenic, and variants of uncertain significance relevant to fetal phenotype, guiding prenatal counseling and pregnancy management. Typical workflow steps: ordering by prenatal/genetics provider, informed consent and pre-test genetic counseling, invasive sample collection in an ambulatory surgical center or hospital, specimen transport to the performing lab, sequencing and bioinformatics analysis, post-test genetic counseling to review results with the patient and obstetric team.

Coding Specifications

Modifier	Description	When to Use
`26`	Professional component	When reporting only the physician interpretation of results separate from the laboratory technical component (rare for PLA tests billed by performing lab).
`52`	Reduced services	When the service is partially reduced or incomplete compared with the full test as ordered.
`53`	Discontinued procedure	When the specimen collection or sequencing is begun but discontinued for clinical reasons.
`62`	Two surgeons	When two qualified providers share responsibility for an invasive fetal sampling procedure (e.g., complex collection) and billing requires recognition of dual coverage.
`78`	Return to operating room for related procedure following surgery	When a subsequent procedure related to fetal sampling or maternal complication occurs in the immediate postoperative period.
`80`	Assistant surgeon	When an assistant surgeon participates in the invasive specimen collection and billing requires an assistant modifier.
`82`	Assistant not available	When an assistant surgeon is unavailable and an assistant is necessary for the invasive sampling.
`AS`	Physician assistant, nurse practitioner, or clinical nurse specialist services	When an advance practice clinician performs the specimen collection or directly supervises collection per payer rules.
`QK`	Medical direction of two, three, or four assistants	When the physician directs multiple assistants during the invasive sampling procedure.
`QX`	CRNA service: medically directed by anesthesiologist	When a CRNA provides anesthesia for the sampling procedure under medical direction.
`QY`	CRNA service: medical direction of one CRNA	When a physician provides medical direction for a single CRNA used during specimen collection.
`TC`	Technical component	When the performing laboratory bills only the technical component of testing separate from professional interpretation.
`FX`	Special handling (for specimen)	When the specimen requires special handling, processing, or transport beyond standard procedures.
`QY`	CRNA service: medical direction of one CRNA	When anesthesia is medically directed for the invasive procedure (repeat entry for emphasis when applicable).

Taxonomy Code	Specialty	Notes
207Q00000X	Maternal-Fetal Medicine (Perinatology)	Specialists who order and interpret prenatal genomic testing and manage high-risk pregnancies.
207L00000X	Obstetrics & Gynecology	Obstetricians who coordinate prenatal diagnosis and sample collection.
2084P0800X	Medical Genetics	Clinical geneticists who interpret genomic findings and provide counseling.
208D00000X	Genetic Counseling	Certified genetic counselors who provide pre- and post-test counseling and consent.
335E00000X	Clinical Laboratory Genetic Molecular Diagnostics	Laboratory specialty performing whole genome sequencing and report generation.

Related Diagnoses

ICD-10 Code	Description	Clinical Relevance
`O35.0XX0`	Maternal care for (suspected) fetal chromosomal abnormality, unspecified trimester, not applicable or not requested	Common indication when ultrasound or family history suggests chromosomal anomaly prompting genomic analysis.
`O35.0XX1`	Maternal care for (suspected) fetal chromosomal abnormality, first trimester	Used when concern arises in the first trimester and sequencing is performed on fetal sample.
`O35.1XX0`	Maternal care for (suspected) fetal genetic disease in fetus, unspecified trimester, not applicable or not requested	Applicable when a rare heritable disorder is suspected and whole genome sequencing is ordered.
`O36.5XX0`	Maternal care for known or suspected fetal abnormality, not elsewhere classified, unspecified trimester	General code for fetal structural anomalies leading to diagnostic testing.
`Z36`	Encounter for antenatal screening of mother	Used when prenatal screening leads to diagnostic sequencing testing decisions.

Related CPT Codes

CPT Code	Description	Relationship to This Procedure
`0335U`	IriSight™ Prenatal Analysis – Proband (whole genome sequence analysis of a fetal sample)	Primary PLA code reporting the proprietary whole genome sequencing assay performed by Variantyx Inc.
`59000`	Amniocentesis, diagnostic, including ultrasound guidance, when performed; with amniotic fluid sampling	Commonly performed to obtain fetal amniotic fluid for `0335U` testing.
`59812`	Induced abortion, by dilation and evacuation, after first trimester	Not typically routine; included for completeness when pregnancy termination follows diagnostic findings (coded only when clinically applicable).
`88182`	Consultation and interpretation of molecular diagnostic testing results, when reported separately	May be used when a pathologist or specialist provides a separate interpretation or consultative report related to sequencing findings.
`99000`	Handling and/or conveyance of specimen	Used by some facilities for special specimen handling or courier services associated with transporting a fetal specimen to the performing lab.