Name of the Procedure:

Whole mitochondrial genome sequencing (Whole mitochondrial genome test, mtDNA sequencing)

Summary

Whole mitochondrial genome sequencing is a specialized genetic test that examines the entire DNA sequence of mitochondria, the energy-producing structures within cells. This test helps identify genetic mutations that may cause various mitochondrial disorders.

Purpose

This procedure addresses conditions associated with mitochondrial dysfunction, such as Leigh syndrome, MELAS, MERFF, NARP, and Leber hereditary optic neuropathy. The primary goal is to diagnose these conditions accurately, allowing for appropriate management and treatment.

Indications

• Patients with symptoms of mitochondrial disorders (muscle weakness, neurodegenerative issues, metabolic abnormalities).
• Individuals with a family history of mitochondrial diseases.
• Suspected cases of mitochondrial encephalomyopathy or unexplained neurodegenerative diseases.

Preparation

• Genetic counseling is recommended to discuss the procedure's implications.
• No specific dietary restrictions, fasting, or medication adjustments are typically required.
• Blood or tissue samples, such as muscle biopsies, may be necessary for the test.

Procedure Description

1. Blood is drawn or a tissue sample is collected.
2. DNA is extracted from the sample.
3. Next-generation sequencing technology is used to read the mitochondrial DNA.
4. The sequence data is analyzed for mutations associated with mitochondrial disorders.
5. A geneticist interprets the results and provides a detailed report.

Duration

The sample collection process takes a few minutes, but the sequencing and analysis can take several weeks.

Setting

The sample collection can be done in an outpatient clinic or hospital. The sequencing and analysis are performed in a specialized laboratory.

Personnel

• Phlebotomists or medical technicians for sample collection.
• Laboratory technicians and geneticists for DNA sequencing and analysis.

Risks and Complications

• Minimal risks associated with blood draws (e.g., slight bruising, infection at the puncture site).
• Rare possibility of muscle pain if a biopsy is performed.

Benefits

• Accurate diagnosis of mitochondrial disorders.
• Informs treatment plans and patient management.
• Provides important genetic information that may benefit family members.

Recovery

• Minimal recovery required after sample collection.
• If a muscle biopsy is performed, follow the care instructions to avoid infection and promote healing.

Alternatives

• Targeted genetic testing for specific mitochondrial mutations.
• Clinical diagnosis based on symptoms and physical examination.
• Less comprehensive tests may miss some genetic mutations compared to whole genome sequencing.

Patient Experience

• Blood draw or tissue sample collection may cause brief discomfort.
• Anesthesia options, if any, for a biopsy can manage pain.
• Patient may feel anxious while awaiting results; genetic counseling can provide support.