Summary & Overview
CPT 81209: BLM (Bloom Syndrome) Gene Testing, Molecular Diagnostic
CPT code 81209 represents a molecular diagnostic laboratory test for detecting common variants in the BLM (Bloom syndrome) gene. This genetic test is used in clinical evaluation for individuals with features suggestive of Bloom syndrome or for targeted variant analysis when a familial pathogenic variant is known. Nationally, precision genetic testing codes such as 81209 are important for access to diagnostic genetics, carrier screening, and guiding clinical management in rare hereditary disorders.
Key payers considered in this publication include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise overview of the clinical context for BLM testing, typical sites of service and service type, and guidance on where to locate payer coverage policies and coding resources. The piece outlines common billing modifiers associated with molecular laboratory services where available and notes when input data is not provided.
The publication also summarizes benchmarks and policy-relevant considerations for laboratory claims processing, reimbursement drivers for single-gene tests versus broader panels, and coding practice points for accurate claim submission. Data not available in the input is identified clearly so readers can locate supplementary payer or clinical documentation as needed.
Billing Code Overview
CPT code 81209 describes a laboratory molecular diagnostic test that detects common changes in the BLM (Bloom syndrome, RecQ helicase–like) gene. The procedure covers the technical laboratory processes required to analyze patient DNA for variants associated with Bloom syndrome.
Service Type: Molecular genetic testing / Clinical laboratory service
Typical Site of Service: Clinical laboratory or reference molecular diagnostics laboratory
Clinical & Coding Specifications
Clinical Context
A typical patient is a young adult or child with features of growth deficiency, photosensitivity, short stature, recurrent infections, or a family history of Bloom syndrome seeking genetic evaluation. A genetics clinic visit includes review of clinical findings and family history, counseling about testing implications, informed consent, and specimen collection (usually blood). The laboratory performs molecular analysis of the BLM (RecQ helicase–like) gene to detect common pathogenic variants. Results return to the ordering geneticist or pediatrician who incorporates findings into diagnosis and management, including referral to oncology surveillance if a pathogenic BLM variant is identified. Insurance preauthorization may be obtained prior to testing; the specimen is processed in a CLIA-certified molecular diagnostics lab with result reporting to the ordering provider.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
26 | Professional component | Use when billing only the professional interpretation component separate from the technical lab work (rare for molecular labs). |
TC | Technical component | Use when billing the technical component of the test (laboratory processing) when professional interpretation billed separately. |