Hemoglobin B occurs due to

Options

A. Deficiency of factor IX
B. Deficiency of factor VII
C. Deficiency of platelets only
D. Deficiency of structures or factor VII

Answer

To answer the question "Hemoglobin B occurs due to," we need to clarify that the question seems to be confused with "Hemophilia B," which is a different condition. However, if we focus on "Hemoglobin B," we can provide a step-by-step solution based on general knowledge about hemoglobin variants.

### Step-by-Step Solution:

1. **Understanding Hemoglobin Variants**:
- Hemoglobin is a protein in red blood cells responsible for transporting oxygen. Variants of hemoglobin can occur due to genetic mutations.

**Hint**: Remember that hemoglobin has different types, and mutations can lead to variants.

2. **Identifying Hemoglobin B**:
- Hemoglobin B is a variant of hemoglobin that can occur due to specific genetic changes. It is important to distinguish it from hemoglobin A, which is the normal adult hemoglobin.

**Hint**: Think about how genetic mutations can lead to different forms of hemoglobin.

3. **Genetic Basis**:
- The occurrence of Hemoglobin B is primarily due to a mutation in the beta-globin gene. This gene is located on chromosome 11 and is responsible for producing the beta chains of hemoglobin.

**Hint**: Focus on the role of genes and mutations in the formation of hemoglobin variants.

4. **Types of Hemoglobin B**:
- There are different types of Hemoglobin B, such as Hemoglobin B (S) which is associated with sickle cell disease. The specific type of mutation will determine the characteristics of the hemoglobin variant.

**Hint**: Consider how different mutations can lead to various forms of hemoglobin and their associated conditions.

5. **Conclusion**:
- Therefore, Hemoglobin B occurs due to mutations in the beta-globin gene, leading to the production of abnormal hemoglobin.

**Hint**: Summarize the key points about genetic mutations and their impact on hemoglobin structure.

### Final Answer:
Hemoglobin B occurs due to mutations in the beta-globin gene, which leads to the production of an abnormal variant of hemoglobin.