A : Myotonic dystrophy is is caused by recessive mutant pleiotropic gene.
R : Gene mutation leads to more synthesis of fibrillin proteins.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1)
B. If both Assertion & Reason are true and the reason is not the correct explanation of the assertion , then mark (2)
C. If Assertion is true statement but Reason is false, then mark (3)
D. If both Assertion and Reason are false statements, then mark (4)

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**: The assertion states that myotonic dystrophy is caused by a recessive mutant pleiotropic gene.
- **Analysis**: Pleiotropic genes are those that influence multiple traits. Myotonic dystrophy is actually caused by a mutation in a gene that is not recessive but is associated with an autosomal dominant inheritance pattern. Therefore, the assertion is incorrect.

2. **Understanding the Reason (R)**: The reason states that gene mutation leads to more synthesis of fibrillin proteins.
- **Analysis**: In the case of myotonic dystrophy, the mutation affects a gene that codes for a kinase enzyme, not fibrillin. This mutation results in a decrease in the synthesis of kinases, which are crucial for muscle contraction. Hence, this statement is also false.

3. **Conclusion**: Since both the assertion and the reason are false, the correct answer to the question is that both A and R are false statements.

### Final Answer:
Both assertion and reason are false statements.

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