Identify the incorrect statement

Options

A. Insertional inactivation of `beta` - galactosidase leads to blue colour colonies.
B. In insertional inactivation , the rDNA is inserted within the coding sequence of an enzyme `beta` galactosidas.
C. Selection of recombinants due to inactivation of antiotic is a cumbersome procedure.
D. Insertional inactivation of `beta` - galactosidase leads to colourless colonies.

Answer

To solve the question "Identify the incorrect statement," we will analyze each statement provided in the context of molecular biology, specifically focusing on the process of insertional inactivation of beta-galactosidase.

### Step-by-Step Solution:

1. **Understand Insertional Inactivation**:
- Insertional inactivation refers to the process where a piece of DNA (recombinant DNA or rDNA) is inserted into the coding sequence of a gene, disrupting its function. In this case, we are focusing on the beta-galactosidase gene (lacZ).

2. **Analyze Statement 1**:
- **Statement**: "Insertional inactivation of beta-galactosidase leads to the blue color colonies."
- **Analysis**: This statement is incorrect. Insertional inactivation of the beta-galactosidase gene results in the loss of function of the enzyme, leading to colorless colonies. Blue colonies indicate that the enzyme is active, which is not the case here.

3. **Analyze Statement 2**:
- **Statement**: "In insertional inactivation, the rDNA is inserted within the coding sequence of an enzyme beta-galactosidase."
- **Analysis**: This statement is correct. The process of insertional inactivation involves inserting rDNA into the coding sequence of beta-galactosidase, which disrupts its function.

4. **Analyze Statement 3**:
- **Statement**: "Selection of recombinants due to inactivation of antibiotic is a cumbersome process."
- **Analysis**: This statement is also correct. The process of selecting recombinant organisms can be complex and involves multiple steps, including the use of antibiotic resistance markers.

5. **Conclusion**:
- After analyzing all three statements, we conclude that the first statement is the incorrect one. The correct answer to the question is **Option 1**.

### Final Answer:
The incorrect statement is: **"Insertional inactivation of beta-galactosidase leads to the blue color colonies."**

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