GJB6 (gap junction protein, beta 6, 30kDa, connexin 30) (eg, nonsyndromic hearing loss) gene analysis, common variants (eg, 309kb [del(GJB6-D13S1830)] and 232kb [del(GJB6-D13S1854)])
CPT4 code
Name of the Procedure:
GJB6 (Gap Junction Protein, Beta 6, 30kDa, Connexin 30) Gene Analysis, Common Variants (e.g., 309kb [del(GJB6-D13S1830)] and 232kb [del(GJB6-D13S1854)]).
Summary
The GJB6 gene analysis tests for specific common variations, particularly deletions in the gene, which are associated with nonsyndromic hearing loss. This procedure involves examining a sample of the patient's DNA to identify genetic changes that might contribute to hearing impairment.
Purpose
The gene analysis aims to:
- Diagnose nonsyndromic hearing loss.
- Identify carriers of genetic mutations associated with hearing loss.
- Provide information for genetic counseling and potential future treatments.
Indications
- Individuals with unexplained hearing loss, especially in cases of early onset.
- Family history of nonsyndromic hearing loss.
- Newborns who fail hearing screenings.
- Individuals seeking information about their genetic predisposition to hearing loss.
Preparation
- No special preparation is usually required.
- Patients may be asked to provide a blood sample or a cheek swab for DNA testing.
- It may be necessary to review family medical history with a genetic counselor before the test.
Procedure Description
- Sample Collection: A blood sample or cheek swab is collected from the patient.
- DNA Extraction: The DNA is extracted from the collected sample.
- Genetic Analysis: The DNA is analyzed using techniques such as PCR (Polymerase Chain Reaction) to detect common deletions in the GJB6 gene.
- Interpretation: A geneticist interprets the results to identify any significant deletions or mutations.
- Tools and Equipment: Blood collection kit, cheek swab, PCR machine, and genetic sequencing tools.
- Anesthesia: Not required for this procedure.
Duration
The sample collection takes about 10-15 minutes. The analysis and results interpretation may take from a few days to several weeks.
Setting
The sample collection can be done in a hospital, outpatient clinic, or a designated collection center. The genetic analysis is done in a specialized laboratory.
Personnel
- Phlebotomists or nurses for sample collection.
- Geneticists or molecular biologists for DNA analysis.
- Genetic counselors to help interpret the results and provide guidance.
Risks and Complications
- Sample Collection: Minor bruising or discomfort at the site of the blood draw.
- Analysis: No significant procedural risks.
- Potential for uncertain or inconclusive results, which may require further testing.
Benefits
- Accurate Diagnosis: Enables the identification of genetic causes of hearing loss.
- Informed Decisions: Assists in family planning and management of the condition.
- Early Intervention: Facilitates timely treatment and interventions for hearing loss.
Recovery
- No recovery time required as the procedure is non-invasive.
Alternatives
- Other Genetic Tests: Different genetic panels or whole exome sequencing may be used.
- Audiological Evaluations: Detailed hearing tests and assessments by audiologists.
- Imaging: MRI or CT scans to look for physical causes of hearing loss.
Pros and Cons of Alternatives:
- **Genetic Tests**: More comprehensive but may be more expensive.
- **Audiological Evaluations**: Non-genetic but essential for functional assessment.
- **Imaging**: Helpful for structural diagnosis but does not provide genetic information.
Patient Experience
- During Procedure: Mild discomfort during blood draw; cheek swabs are painless.
- After Procedure: No significant after-effects; patients can resume normal activities immediately.
- Pain Management: Generally not necessary; over-the-counter pain relief if needed for blood draw site tenderness.