Select incorrect statement w.r.t. RNAi

Options

A. dsDNA binds target mRNA and initiate RNAi
B. Agrobacterium vector is used to introduce nematode specific gene into host plant
C. ssRNA binds target mRNA and initiate RNAi
D. Both (2) & (3)

Answer

### Step-by-Step Solution:

1. **Understanding RNA Interference (RNAi)**:
- RNA interference is a biological process where RNA molecules inhibit gene expression or translation, by neutralizing targeted mRNA molecules.

2. **Identifying the Statements**:
- We need to evaluate the given statements regarding RNAi to find the incorrect one.

3. **Evaluating the First Statement**:
- The first statement claims: "A double-stranded DNA binds to target mRNA and initiates RNA interference."
- This statement is incorrect because RNA interference is initiated by double-stranded RNA (not DNA) that binds to the target mRNA.

4. **Evaluating the Second Statement**:
- The second statement claims: "Agrobacterium vector is used to introduce nematode-specific gene into host plant."
- This statement is correct. Agrobacterium is commonly used in genetic engineering to introduce specific genes into plants.

5. **Evaluating the Third Statement**:
- The third statement claims: "Single-stranded RNA binds to target mRNA and initiates RNA interference."
- This statement is also correct. Single-stranded RNA can indeed bind to target mRNA and lead to its degradation.

6. **Conclusion**:
- After evaluating all statements, the first statement is the only incorrect one regarding RNA interference.

### Final Answer:
The incorrect statement with respect to RNAi is: "A double-stranded DNA binds to target mRNA and initiates RNA interference."

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