The loss of activity of gene located at cloning site is knouwn as

Options

A. Elution
B. Transformation
C. Insertional inactivation
D. Down stream processing

Answer

To solve the question regarding the loss of activity of a gene located at a cloning site, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question asks about the term used to describe the loss of activity of a gene when a foreign DNA is inserted into a cloning site.

2. **Analyze the Options**: We have four options to consider:
- **Illusion**: This term refers to the isolation of DNA fragments from agarose gel, which is not related to gene activity.
- **Transformation**: This process involves the uptake of foreign DNA by a cell, but it does not specifically refer to the loss of gene activity.
- **Insertional Inactivation**: This is the process where the insertion of foreign DNA into a gene disrupts its function, leading to the loss of activity of that gene. This seems to be the correct option.
- **Downstream Processing**: This term refers to the purification of products after fermentation and is unrelated to gene activity.

3. **Identify the Correct Answer**: Based on the analysis, the correct answer is **Insertional Inactivation**. This term specifically describes the phenomenon where the insertion of foreign DNA into a gene results in the gene losing its functional activity.

### Final Answer:
The loss of activity of a gene located at a cloning site is known as **Insertional Inactivation**.