Which was first diease treated by the method of gene therapy ?

Options

A. SCID
B. AIDS
C. T.B.
D. Leukaemia

Answer

**Step-by-Step Solution:**

1. **Understanding Gene Therapy**: Gene therapy is a technique that modifies a person's genes to treat or prevent disease. It involves introducing, removing, or altering genetic material within a person's cells.

2. **Identifying the First Clinical Application**: The first clinical application of gene therapy occurred in 1990. This is a significant historical milestone in the field of biotechnology.

3. **Patient Case**: The first patient to receive gene therapy was a 4-year-old girl. This highlights the real-world application and impact of gene therapy on patients.

4. **Condition Treated**: The girl was treated for ADA deficiency. ADA stands for Adenosine Deaminase, an enzyme that is crucial for the immune system's proper functioning.

5. **Consequences of ADA Deficiency**: The absence of the ADA enzyme leads to Severe Combined Immunodeficiency Disorder (SCID). This condition is characterized by a severely compromised immune system, making patients highly susceptible to infections.

6. **Mechanism of Gene Therapy for SCID**: In gene therapy for SCID, a functional copy of the ADA gene is introduced into the patient's lymphocytes using a retroviral vector. This allows the patient's body to produce the ADA enzyme, thereby restoring immune function.

7. **Conclusion**: Therefore, the first disease treated by gene therapy is Severe Combined Immunodeficiency Disorder (SCID).

**Final Answer**: The first disease treated by the method of gene therapy is SCID (Severe Combined Immunodeficiency Disorder).

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