One amongst the following is not a PCR application :

Options

A. Detection of syphlis
B. Study of cause of congenital disease
C. Detection of hepatitis
D. Treatment against SCID

Answer

**Step-by-Step Solution:**

1. **Understand the Question**: The question asks to identify which of the given options is NOT an application of Polymerase Chain Reaction (PCR).

2. **Recall PCR Applications**: PCR is a technique used to amplify DNA and has several applications in various fields, including:
- Diagnosis of pathogens (e.g., detecting diseases caused by specific pathogens).
- Diagnosis of specific mutations.
- DNA fingerprinting.
- Detection of specific microorganisms.
- Parental diagnosis (e.g., determining paternity).
- Diagnosis of plant pathogens.
- Applications in paleontology (e.g., studying ancient DNA).

3. **Analyze Each Option**:
- **Option 1: Detection of Syphilis**: This is a disease caused by a pathogen, and PCR can be used to detect it. Therefore, this is a PCR application.
- **Option 2: Study of Cause of Congenital Disease**: Congenital diseases can be diagnosed through genetic testing, which can involve PCR. Hence, this is also a PCR application.
- **Option 3: Detection of Hepatitis**: Hepatitis is a viral infection that can be detected using PCR. This is a valid application of PCR.
- **Option 4: Treatment Against SCID**: Severe Combined Immunodeficiency (SCID) is a genetic disorder. While PCR can be used to diagnose SCID, it is not used for treatment. PCR is primarily a diagnostic tool, not a treatment method.

4. **Conclusion**: Based on the analysis, the option that is NOT a PCR application is **Option 4: Treatment Against SCID**.

**Final Answer**: Option 4: Treatment Against SCID is not a PCR application.

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