Summary & Overview
CPT 81250: G6PC Gene Molecular Diagnostic Test
CPT code 81250 represents a technical molecular diagnostic test for detecting specific changes in the G6PC gene (glucose–6‑phosphatase, catalytic subunit). This test supports diagnosis of genetic conditions such as glycogen storage disease type I and informs clinical management and genetic counseling. Molecular testing codes like 81250 are increasingly important nationally as precision medicine and genetic diagnostics expand across care settings. Key payers in the national landscape include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare and Medicare.
Readers will find a concise overview of clinical context and why G6PC testing matters, plus what to expect from payer coverage and common billing practices for the technical component. The report provides benchmarks and policy context relevant to laboratory billing, highlights typical sites of service (clinical and hospital laboratories), and outlines areas where coverage rules and prior authorization practices commonly affect access and reimbursement. Data not available in the input is noted where applicable.
Billing Code Overview
CPT code 81250 describes a technical laboratory test to detect specific changes in the gene for glucose–6‑phosphatase, catalytic subunit (G6PC). The procedure involves molecular genetic analysis by a lab analyst to identify pathogenic variants in the G6PC gene associated with glycogen storage disease type I.
Service type: Molecular diagnostic / genetic testing (technical component)
Typical site of service: Clinical laboratory or hospital laboratory
Clinical & Coding Specifications
Clinical Context
A typical patient is an infant or child with suspected glycogen storage disease type I or recurrent fasting hypoglycemia, referred by a pediatric metabolic specialist for molecular testing of the G6PC gene to confirm pathogenic variants. Clinical workflow: a clinician orders 81250 after biochemical evaluation (elevated lactate, hypoglycemia, hepatomegaly) and genetic counseling. A blood sample or buccal swab is collected, sent to a molecular diagnostics laboratory. The lab technician performs the technical assay to detect sequence changes in G6PC; results are reported to the ordering clinician and genetic counselor who integrate findings with clinical and biochemical data for diagnosis, family counseling, and cascade testing.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
26 | Professional component | Use when reporting the MD pathologist/geneticist interpretation separate from the laboratory technical component (rare for single lab CPT 81250 if billed separately). |
TC | Technical component |