Which of the following DNA segments have 1-6 bp length?

Options

A. Dystrophin
B. STRs
C. Minisatellites
D. Both (1) & (3)

Answer

To solve the question regarding which DNA segments have a length of 1 to 6 base pairs, we can follow these steps:

### Step 1: Understand the Options
Identify the DNA segments mentioned in the question. The options include Dystrophin and Short Tandem Repeats (STRs).

### Step 2: Analyze Dystrophin
Dystrophin is a large protein coding gene found in muscle cells. It has a very long DNA sequence, exceeding 2200 kilobases (kb). Therefore, it does not fall within the 1 to 6 base pair length range.

### Step 3: Analyze Short Tandem Repeats (STRs)
Short Tandem Repeats (STRs) are sequences of DNA that consist of repeating units of 1 to 6 base pairs. These are known for their variability and are often used in genetic profiling and forensic analysis. STRs are indeed within the specified range of 1 to 6 base pairs.

### Step 4: Compare with Other Options
If there were other options provided (like mini-satellites), we would analyze them as well. Mini-satellites consist of longer repeat units, typically ranging from 10 to 60 base pairs, which does not fit the criteria of 1 to 6 base pairs.

### Conclusion
Based on the analysis, the correct answer is Short Tandem Repeats (STRs), as they are the only DNA segments that fit the criteria of having a length of 1 to 6 base pairs.

### Final Answer
The DNA segment that has a length of 1 to 6 base pairs is **Short Tandem Repeats (STRs)**.

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