DNA probe is used for

Options

A. DNA fingerprinting
B. Detectction of pathogeni bacteria
C. Medical geneticss to find whether a preson carries a particular gene or not
D. All of the above

Answer

### Step-by-Step Solution:

1. **Understanding DNA Probes**:
- A DNA probe is a short, single-stranded segment of DNA that is complementary to a specific nucleic acid sequence. It is used to detect the presence of that sequence in a sample.

2. **Application in DNA Fingerprinting**:
- DNA probes are essential in the process of DNA fingerprinting, which involves identifying unique DNA fragments. This is typically done using techniques like electrophoresis and Southern blotting, where DNA probes help in detecting specific nucleic acid sequences within those fragments.

3. **Detection of Pathogenic Bacteria**:
- DNA probes can also be used to detect pathogenic bacteria. By identifying specific nucleic acid sequences associated with these bacteria, scientists can determine their presence in a sample, whether from a fetus or other organisms.

4. **Medical Genetics**:
- In the field of medical genetics, DNA probes are used to determine if an individual carries a particular gene. This is crucial for genetic testing and understanding inherited conditions.

5. **Conclusion**:
- Since DNA probes are utilized in all the mentioned applications—DNA fingerprinting, detection of pathogenic bacteria, and medical genetics—the correct answer to the question is option 4: all of the above.