The most striking example of point mutation is found in a disease called

Options

A. Sickle cell anaemia
B. Colour blindness
C. Laesh-Nyhn Syndrome
D. Thallesemia

Answer

**Step-by-Step Solution:**

1. **Understanding Point Mutation**: A point mutation refers to a change in a single nucleotide base in the DNA sequence. This can lead to changes in the amino acid sequence of proteins, which can affect their function.

2. **Identifying the Disease**: The question asks for a disease that is a striking example of point mutation. Among the options provided (sickle cell anemia, colorblindness, Leishnian syndrome, and thalassemia), we need to identify which one is primarily caused by a point mutation.

3. **Analyzing Sickle Cell Anemia**: Sickle cell anemia is caused by a specific point mutation in the beta-globin gene located on chromosome 11. At the 6th position of the beta chain, the nucleotide adenine (A) is replaced by thymine (T), leading to the substitution of the amino acid glutamic acid (Glu) with valine (Val).

4. **Effects of the Mutation**: This mutation causes the red blood cells (RBCs) to change from a normal round shape to a sickle shape. The sickle-shaped RBCs are less efficient at carrying oxygen and can lead to various health complications.

5. **Conclusion**: Based on the information provided, the most striking example of point mutation is found in sickle cell anemia.

**Final Answer**: The most striking example of point mutation is found in a disease called **sickle cell anemia**.

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