Genes that are expressed as RNA are called

Options

A. ESTs
B. Micro-satellites
C. VNTRs
D. SNPs

Answer

To answer the question "Genes that are expressed as RNA are called," we need to analyze the options provided and identify which one corresponds to genes expressed as RNA.

### Step-by-Step Solution:

1. **Understanding the Question**: The question is asking for a specific term that describes genes which are expressed as RNA. This means we are looking for a type of genetic marker or term that directly relates to RNA expression.

2. **Evaluating the Options**:
- **Option A: EST (Expressed Sequence Tag)**: This term refers to short sequences of DNA that are derived from expressed genes. ESTs are used to identify gene transcripts and are indeed related to RNA expression.
- **Option B: Microsatellites**: These are repeating sequences in the genome, known as Variable Number Tandem Repeats (VNTRs). They do not specifically refer to RNA expression.
- **Option C: SNP (Single Nucleotide Polymorphism)**: This refers to variations at a single nucleotide position in the DNA sequence. While SNPs can be associated with gene expression, they do not specifically refer to genes expressed as RNA.

3. **Conclusion**: After evaluating the options, it is clear that the correct answer is **Option A: EST (Expressed Sequence Tag)**, as it directly relates to genes that are expressed as RNA.

### Final Answer:
Genes that are expressed as RNA are called **EST (Expressed Sequence Tag)**.

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