An example of disease of molecular muttion is

Options

A. Sickle cell anaemia
B. Erythroblastosis foetalis
C. Haemophilia
D. Anaemia

Answer

**Step-by-Step Solution:**

1. **Understanding Molecular Mutation**:
- Molecular mutations refer to changes in the DNA sequence that can lead to alterations in the structure and function of proteins. These mutations can result in various diseases.

2. **Identifying the Options**:
- The question provides several options: sickle cell anemia, erythroblastosis, phytolysis, hemophilia, and anemia. We need to determine which of these is caused by a molecular mutation.

3. **Analyzing Sickle Cell Anemia**:
- Sickle cell anemia is a well-known genetic disorder caused by a mutation in the beta-globin gene of hemoglobin. This mutation leads to the production of abnormal hemoglobin (hemoglobin S), which causes red blood cells to assume a sickle shape.

4. **Understanding the Mechanism**:
- The mutation in sickle cell anemia involves a single nucleotide change in the DNA sequence, which alters the amino acid sequence of the beta chain of hemoglobin. This results in the sickling of red blood cells, leading to various health complications.

5. **Conclusion**:
- Based on the analysis, sickle cell anemia is indeed an example of a disease caused by molecular mutation due to the specific changes in the beta chain of hemoglobin.

**Final Answer**: Sickle cell anemia is an example of a disease of molecular mutation.

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