The ADA gene is crucial for:

Options

A. erythropoiesis
B. functioning of immune system
C. embryonic development
D. early dectection of SCID

Answer

To solve the question regarding the importance of the ADA gene, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the ADA Gene**: The ADA gene is responsible for producing the ADA enzyme, which is essential for certain biological functions in the body.

2. **Function of the ADA Enzyme**: The ADA enzyme plays a critical role in the immune system. It helps in the breakdown of toxic metabolites that can accumulate in immune cells.

3. **Consequences of ADA Deficiency**: If the ADA enzyme is absent or deficient, it leads to a condition known as Severe Combined Immunodeficiency (SCID). This is a serious immunodeficiency disease where the immune system is severely compromised.

4. **Evaluate the Options**:
- **Erythropoiesis**: This refers to the formation of red blood cells, which is not directly related to the ADA gene.
- **Functioning of Immune System**: This is directly related to the ADA gene, as the enzyme produced by this gene is crucial for the immune response.
- **Embryonic Development**: While important, this is not the primary function of the ADA gene.
- **Early Detection of SCID**: The ADA gene is not primarily responsible for the early detection of SCID; it is more about the functioning of the immune system.

5. **Conclusion**: Based on the analysis, the ADA gene is crucial for the functioning of the immune system.

### Final Answer:
The ADA gene is crucial for the functioning of the immune system.

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