Probes used in DNA finger-printing initially

Options

A. Single stranded RNA
B. Mini satellite
C. 19 base long oligonucleotide
D. All of the above

Answer

To solve the question regarding the probes used in DNA fingerprinting, we can follow these steps:

### Step 1: Understand the Concept of DNA Fingerprinting
DNA fingerprinting is a technique used to identify individuals based on their unique DNA profiles. It relies on the analysis of specific regions of the DNA that are highly variable among individuals.

### Step 2: Identify the Types of Probes Used
In DNA fingerprinting, probes are short sequences of DNA or RNA that are complementary to the target DNA sequences. The question asks about the types of probes used initially in DNA fingerprinting.

### Step 3: Analyze the Given Options
The options provided are:
1. Single-stranded RNA
2. Mini-satellite
3. 19 base long oligonucleotide
4. Oligonucleotide
5. All of the above

### Step 4: Evaluate Each Option
- **Single-stranded RNA**: This can be used as a probe in some DNA fingerprinting techniques.
- **Mini-satellite**: This refers to regions of DNA that consist of repeating sequences and are commonly used in DNA profiling.
- **19 base long oligonucleotide**: Oligonucleotides of this length can serve as specific probes for identifying unique sequences in DNA.
- **Oligonucleotide**: This is a general term for short DNA or RNA molecules, which are indeed used in DNA fingerprinting.

### Step 5: Conclusion
Since all the options listed can be considered as probes used in DNA fingerprinting, the correct answer is "All of the above."

### Final Answer
**All of the above.**

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