Select the incorrect statement.

Options

A. Insertional inactivation technique helps in identification of the recombinant transformants with non - transformants by forming colourless colonies.
B. Insertional inactivation of `beta` - galactosidase leads to the formation of colourless colonies.
C. Insertional inactivation of `beta` - galactosidase leads to the formation of blue colour colonies.
D. In insertional inactivation , the rDNA is inserted within the coding sequence of an enzyme `beta` galactosidase.

Answer

To solve the question of selecting the incorrect statement related to biotechnology techniques, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Insertional Inactivation**:
- Insertional inactivation refers to the process where the insertion of a foreign DNA sequence into a gene disrupts its function. This is often used in molecular biology to identify whether a gene of interest has been successfully inserted into a vector.

**Hint**: Recall that insertional inactivation is used to determine if the desired gene has been successfully integrated into the host organism.

2. **Identify the Role of Selectable Markers**:
- Selectable markers are genes that confer a trait suitable for artificial selection. They help in identifying transformants (cells that have taken up the foreign DNA) from non-transformants (cells that have not).

**Hint**: Think about how selectable markers help differentiate between successful and unsuccessful transformations in genetic engineering.

3. **Analyze the Statements**:
- We need to evaluate the statements provided in the question to determine which one is incorrect. The statements relate to the outcomes of using beta-galactosidase as a selectable marker.

**Hint**: Carefully read each statement and compare it to the principles of insertional inactivation and the behavior of beta-galactosidase.

4. **Evaluate the Specific Statements**:
- **Statement 1**: "Insertional inactivation allows for identification of transformants and non-transformants." - This is correct.
- **Statement 2**: "Colorless colonies are formed due to insertional inactivation of beta-galactosidase." - This is correct.
- **Statement 3**: "Blue color colony is formed due to insertional inactivation." - This is incorrect because blue colonies indicate non-transformants where insertional inactivation has not occurred.
- **Statement 4**: "Transformants appear colorless due to the inactivation of beta-galactosidase." - This is correct.

**Hint**: Focus on the color outcomes of colonies based on the presence or absence of the beta-galactosidase enzyme.

5. **Select the Incorrect Statement**:
- Based on the analysis, the incorrect statement is that "Blue color colony is formed due to insertional inactivation." This is false because blue colonies indicate that the insertional inactivation did not occur.

**Hint**: Remember that the color of the colonies directly relates to whether the gene of interest has been successfully inserted or not.

### Final Answer:
The incorrect statement is: "Blue color colony is formed due to insertional inactivation."