Early detection of a disease is possible by

Options

A. PCR
B. gene therapy
C. recombinant DNA technology and ELISA
D. both (a) and (c)

Answer

**Step-by-Step Solution:**

1. **Understanding the Importance of Early Detection:**
- Early detection of a disease is crucial for effective treatment. It allows for timely intervention, which can significantly improve patient outcomes.

2. **Identifying Conventional Methods:**
- Traditional methods for disease detection include urine analysis and blood tests. However, these methods may not always be effective for early diagnosis.

3. **Recognizing Advanced Techniques:**
- Advanced techniques that have proven to be more effective for early disease detection include:
- **Polymerase Chain Reaction (PCR):** This technique amplifies small amounts of DNA, allowing for the detection of genetic material from pathogens even in the early stages of infection.
- **Recombinant DNA Technology:** This method involves manipulating DNA to identify genetic changes associated with diseases.
- **Enzyme-Linked Immunosorbent Assay (ELISA):** This is a test that detects and quantifies proteins, such as antibodies, which may indicate the presence of a disease.

4. **Conclusion:**
- The combination of these advanced techniques (PCR, recombinant DNA technology, and ELISA) enables early detection of diseases by identifying small changes in DNA or the presence of specific proteins.

5. **Final Answer:**
- Therefore, the correct answer to the question "Early detection of a disease is possible by" is option D, which includes both PCR and ELISA.

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