Which of the mutagen causes frame shift mutation

Options

A. 2 Aminopurine
B. Proflavine
C. 5 Bromouracil
D. Methane sulphonates

Answer

### Step-by-Step Solution:

1. **Understand Frameshift Mutation**:
- A frameshift mutation occurs when there is an addition or deletion of nucleotides in a DNA sequence that is not in multiples of three. This alters the reading frame of the genetic code.

2. **Identify Causes of Frameshift Mutations**:
- Frameshift mutations can be caused by the loss (deletion) or gain (insertion) of nucleotides. This change results in a completely different translation from the original sequence.

3. **Examples of Frameshift Mutations**:
- For instance, if the original sequence is "GAC TAG GT", and a nucleotide is lost, the sequence may change to "GAC TAG", resulting in a shift in the reading frame. Similarly, if a nucleotide is added, such as changing "GAT" to "GAAT", it also causes a shift in the reading frame.

4. **Identify Mutagens**:
- Certain chemicals can induce frameshift mutations. The video mentions proflavin and acridine as key mutagens that cause frameshift mutations.

5. **Differentiate Between Types of Mutagens**:
- Other mutagens like 2-Aminopurine, 5-Bromouracil, and Methane Sulphonates are classified as base analogues and typically cause transition mutations rather than frameshift mutations.

6. **Conclusion**:
- Based on the information, the correct answer to the question regarding which mutagen causes frameshift mutations is **proflavin**.