Which kind of therapy was given in 1990 to a four year old girl with adenosine deaminase (ADA) deficiency?

Options

A. Gene therapy
B. Chemotherapy
C. Immunotherapy
D. Radiation therapy

Answer

**Step-by-Step Text Solution:**

1. **Understanding ADA Deficiency**: Adenosine deaminase (ADA) deficiency is a genetic disorder that affects the immune system. It is caused by the lack of the enzyme adenosine deaminase, which is crucial for the production of lymphocytes, particularly T-lymphocytes.

2. **Treatment Options**: In 1990, the treatment options for ADA deficiency included:
- Bone marrow transplant: This procedure involves replacing the defective bone marrow with healthy marrow from a donor.
- Enzyme replacement therapy: This involves administering the ADA enzyme directly through injections.

3. **Introduction of Gene Therapy**: In 1990, a significant advancement was made when a four-year-old girl became the first patient to receive gene therapy for ADA deficiency. This marked a pioneering step in the use of gene therapy for treating genetic disorders.

4. **Procedure of Gene Therapy**:
- **Isolation of Lymphocytes**: Lymphocytes were extracted from the patient's blood.
- **Culturing Cells**: These lymphocytes were then cultured in a laboratory to increase their numbers.
- **Introducing Functional ADA**: The cultured lymphocytes were introduced to a functional copy of the ADA gene (cDNA) using a retrovirus as a vector. This retrovirus helped deliver the functional gene into the lymphocytes.

5. **Reintroduction to the Patient**: After the lymphocytes were genetically modified to express the ADA enzyme, they were reintroduced into the patient's body.

6. **Need for Periodic Infusions**: Since the modified lymphocytes are not immortal, the patient required periodic infusions of these genetically modified cells to maintain adequate levels of the ADA enzyme.

7. **Potential for Permanent Cure**: The transcript also notes that for a permanent solution, introducing the ADA gene at an early embryonic stage would be ideal, as it would ensure that all cells in the body could produce the necessary enzyme.

**Final Answer**: The therapy given in 1990 to the four-year-old girl with ADA deficiency was **gene therapy**.

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