Which is not true about PCR (Polymerase Chain Reaction) ?

Options

A. PCR can amplify very small amount of DNA
B. It can be used to detect HIV in suspects
C. Only RNA can be used as primer
D. Used to detect mutation in genes

Answer

To determine which statement about PCR (Polymerase Chain Reaction) is not true, we will analyze each of the provided statements one by one.

### Step-by-Step Solution:

1. **Statement Analysis**:
- **Statement 1**: "Can amplify very small amount of DNA."
- This statement is true. PCR is designed to amplify small quantities of DNA, making it a powerful tool in molecular biology.

- **Statement 2**: "Can be used to detect HIV patients suspects."
- This statement is also true. PCR can be used to detect the presence of HIV by amplifying viral RNA or DNA from the patient's sample.

- **Statement 3**: "Only RNA can be used as a primer."
- This statement is false. In PCR, both DNA and RNA primers can be used, but typically DNA primers are more common. Therefore, this statement is incorrect.

- **Statement 4**: "Used to detect mutations in genes."
- This statement is true. PCR can be used to amplify specific regions of DNA where mutations are suspected, allowing for further analysis.

2. **Conclusion**:
- The statement that is not true about PCR is: "Only RNA can be used as a primer." This is incorrect because DNA primers are also commonly used in PCR.

### Final Answer:
The statement that is not true about PCR is: **"Only RNA can be used as a primer."**

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