A: Production of hirudin from transgenic Brassica required use of synthetic gene.
R : Eukaryotic genes have intron sequences that need to be spliced out.

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 but 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 Hirudin**: Hirudin is a natural protein produced by leeches, specifically known for its anticoagulant properties. It prevents blood from clotting, making it useful in medical treatments for heart patients.

2. **Transgenic Brassica**: The production of hirudin can be achieved through genetic engineering in plants, specifically using a transgenic variety of Brassica napus (rapeseed). This involves inserting the gene responsible for producing hirudin into the plant's genome.

3. **Synthetic Gene Requirement**: The reason for using a synthetic gene in this process is that eukaryotic genes, such as those from leeches, contain introns. Introns are non-coding sequences that interrupt the coding sequences (exons) of a gene.

4. **Intron Splicing**: In eukaryotic cells, introns must be removed through a process called splicing to produce mature mRNA that can be translated into a functional protein. However, when creating a synthetic gene for use in transgenic plants, it is beneficial to eliminate these introns, as they are not necessary for the expression of the gene in the plant system.

5. **Conclusion**: Therefore, the statement that the production of hirudin from transgenic Brassica requires the use of a synthetic gene is true. The reason given, that eukaryotic genes have intron sequences that need to be spliced out, is also true. Thus, both the statement and the reason are correct and related.

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