The first clinical gene therapy was done for the treatment of

Options

A. AIDS
B. Cancer
C. Cystic fibrosis
D. SCIO (Severe Combined :mmuno Defi- ciency resulting from deficiency of AD(A)

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 correcting defective genes responsible for disease development.

2. **Identifying the First Clinical Gene Therapy**: The first successful clinical gene therapy was performed on a patient with a specific genetic disorder.

3. **Recognizing the Disease**: The disease in question is Severe Combined Immunodeficiency (SCID). This condition is characterized by a severely compromised immune system, making individuals highly susceptible to infections.

4. **Cause of SCID**: SCID can be caused by various genetic mutations, but one common cause is the deficiency of the enzyme adenosine deaminase (ADA). This enzyme is crucial for the immune system's functioning.

5. **Treatment Through Gene Therapy**: In the first clinical gene therapy, the treatment involved correcting the genetic defect that led to the deficiency of the ADA enzyme. This was done to restore the immune function of the patient.

6. **Patient Details**: The first patient to receive this gene therapy was a 4-year-old girl suffering from SCID. The successful treatment improved her immune system, allowing her to fight infections more effectively.

7. **Conclusion**: Therefore, the first clinical gene therapy was conducted for the treatment of Severe Combined Immunodeficiency Disease (SCID), resulting from the deficiency of the enzyme adenosine deaminase.

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