Alpha thalassemia is controlled by

Options

A. one gene located on chromosome 11
B. one gene located on chromosome 16
C. two gene located on chromosome 11
D. two gene located on chromosome 16

Answer

To answer the question "Alpha thalassemia is controlled by," we need to analyze the options provided and understand the genetic basis of alpha thalassemia.

### Step-by-Step Solution:

1. **Understanding Alpha Thalassemia**:
- Alpha thalassemia is a blood disorder characterized by reduced production of alpha globin chains, which are essential components of hemoglobin.

2. **Identifying the Genes Involved**:
- The condition is caused by mutations in genes responsible for producing alpha globin chains. Specifically, these are the HbA1 and HbA2 genes.

3. **Chromosomal Location**:
- The genes for alpha globin (HbA1 and HbA2) are located on chromosome 16. This is crucial for determining the correct answer.

4. **Evaluating the Options**:
- Option 1: 1 gene located on chromosome 11 - Incorrect.
- Option 2: 1 gene located on chromosome 16 - Incorrect.
- Option 3: 2 genes located on chromosome 11 - Incorrect.
- Option 4: 2 genes located on chromosome 16 - Correct.

5. **Conclusion**:
- Alpha thalassemia is controlled by 2 genes located on chromosome 16 (HbA1 and HbA2).

### Final Answer:
Alpha thalassemia is controlled by **2 genes located on chromosome 16**.

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