PMP22 (peripheral myelin protein 22) (eg, Charcot-Marie-Tooth, hereditary neuropathy with liability to pressure palsies) gene analysis; full sequence analysis
CPT4 code
Name of the Procedure:
Peripheral Myelin Protein 22 (PMP22) Gene Analysis; Full Sequence Analysis
Summary
Peripheral Myelin Protein 22 (PMP22) gene analysis is a genetic test that examines the full sequence of the PMP22 gene. This test is used to identify mutations or abnormalities that may be linked to certain inherited neuropathies, such as Charcot-Marie-Tooth disease and hereditary neuropathy with liability to pressure palsies.
Purpose
This procedure addresses inherited neuropathies by identifying specific genetic mutations within the PMP22 gene. The main goal is to diagnose conditions like Charcot-Marie-Tooth disease and hereditary neuropathy with liability to pressure palsies. Early and accurate diagnosis can lead to better management and treatment plans.
Indications
- Patients showing symptoms of peripheral neuropathy such as muscle weakness, decreased muscle size, or reduced sensation.
- Family history of Charcot-Marie-Tooth disease or similar hereditary neuropathies.
- Individuals experiencing frequent pressure palsies or related symptoms.
Preparation
- No specific fasting or medication adjustments are generally required.
- A detailed family medical history is often reviewed.
- Informed consent must be obtained after explaining the procedure and associated risks.
Procedure Description
- Sample Collection: A blood sample is drawn from the patient, typically from a vein in the arm.
- DNA Extraction: Laboratory technicians extract DNA from the blood sample.
- Gene Sequencing: The PMP22 gene is sequenced using advanced genetic sequencing technologies to identify any mutations.
- Analysis: Geneticists analyze the sequencing data to detect variations or abnormalities in the PMP22 gene.
Tools and technologies used include blood collection kits, DNA extraction kits, and genetic sequencers. No anesthesia or sedation is required for this procedure.
Duration
The blood draw takes about 10-15 minutes. The entire process, including sequencing and analysis, can take several weeks (typically 2-4 weeks).
Setting
The blood sample is usually collected in an outpatient clinic or laboratory setting. The gene sequencing and analysis are performed in a specialized laboratory.
Personnel
- Phlebotomist or nurse for blood draw.
- Laboratory technicians for DNA extraction.
- Geneticists or molecular biologists for gene sequencing and analysis.
Risks and Complications
- Minimal risks include slight bleeding, bruising, or infection at the blood draw site.
- Rare risks are related to the psychological impact of genetic testing results, which should be managed with proper counseling.
Benefits
- Accurate diagnosis of hereditary neuropathies.
- Better management and treatment planning.
- Informed family planning for patients with inherited conditions.
Recovery
- There is no recovery time needed for the blood draw itself.
- Psychological support may be provided based on the testing results.
Alternatives
- Comparative genetic tests for other genes linked to neuropathies.
- Electromyography (EMG) and nerve conduction studies.
- Pros include a broader analysis of causative factors; cons may include less specificity for PMP22-related conditions.
Patient Experience
- The patient will feel a small prick during the blood draw and may experience slight discomfort or bruising.
- Emotional experiences may vary based on the outcome of the test. Counseling is recommended to help patients understand the results and implications.