Name of the Procedure:

GBA (glucosidase, beta, acid) gene analysis, common variants (e.g., N370S, 84GG, L444P, IVS2+1G>A)

Summary

The GBA gene analysis is a genetic test that identifies common mutations in the GBA gene, such as N370S, 84GG, L444P, and IVS2+1G>A. This test is primarily used to diagnose Gaucher disease, a genetic disorder that affects many of the body's organs and tissues.

Purpose

The GBA gene analysis is used to diagnose Gaucher disease, which results from a deficiency in the glucocerebrosidase enzyme. The primary goal of this test is to identify specific genetic mutations so that appropriate medical treatment can commence. It can also provide information for family planning and genetic counseling.

Indications

• Symptoms of Gaucher disease such as an enlarged spleen or liver, bone pain, fatigue, or easy bruising.
• A family history of Gaucher disease.
• Unexplained thrombocytopenia (low platelet count).
• Abnormal blood work that suggests storage disorders.

Preparation

• No special preparation is usually required.
• Patients may be asked about their family medical history.
• A routine blood sample will be collected; no fasting is needed.

Procedure Description

1. Collection of a blood sample or, occasionally, a saliva sample.
2. The sample is sent to a laboratory where DNA is extracted.
3. The GBA gene is sequenced to look for common mutations like N370S, 84GG, L444P, and IVS2+1G>A.
4. Results are analyzed and interpreted by a geneticist.

Tools used include:

• Blood collection kit
• DNA extraction and sequencing equipment

Anesthesia is not required for this genetic test.

Duration

Collecting the sample takes a few minutes. Laboratory analysis typically takes several weeks.

Setting

The sample collection can be done in a hospital, clinical laboratory, or outpatient clinic.

Personnel

• Phlebotomist or nurse for sample collection.
• Laboratory geneticist/technician for processing and analysis.
• Genetic counselor or physician for result interpretation and consultation.

Risks and Complications

• Minimal risk from blood draw, such as slight pain or bruising at the puncture site.
• Rarely, there may be complications like fainting or infection.

Benefits

• Accurate diagnosis of Gaucher disease.
• Early intervention and treatment planning.
• Informative for genetic counseling, personal, and family health awareness.

Recovery

• No recovery time needed post blood draw.
• Normal activities can be resumed immediately.
• Follow-up genetic counseling session to discuss test results.

Alternatives

• Enzyme assays to measure glucocerebrosidase activity.
• Bone marrow biopsy (invasive, less commonly used).
• Other genetic testing methods like whole exome or genome sequencing.

Pros and cons of alternatives include invasiveness, accuracy, and comprehensiveness of genetic information obtained.

Patient Experience

The blood draw might cause mild discomfort similar to any routine blood test. Results will take a few weeks to be available, during which anxiety might be experienced. Genetic counseling can provide support and detailed explanations during this period. Pain is managed through standard blood draw procedures, ensuring minimal discomfort.