A transgenic mice that carries a desired gene replaced by other gene is called

Options

A. knock out mice
B. clone
C. chimera
D. surrogate

Answer

**Step-by-Step Solution:**

1. **Understanding Transgenic Mice**: Transgenic mice are genetically modified organisms that have had a foreign gene inserted into their genome. This is done to study the effects of the gene or to produce certain proteins.

2. **Gene Replacement**: In the context of this question, we are focusing on a situation where a desired gene is replaced by another gene. The process of replacing a gene in a transgenic organism is significant in genetic research and therapy.

3. **Definition of Knockout Mice**: When a specific gene is removed or "knocked out" and replaced with another gene, the resulting organism is referred to as "knockout mice." This term specifically describes mice that have had a gene of interest inactivated or replaced.

4. **Evaluating Options**:
- **Option A: Knockout Mice** - This is the correct answer as it describes mice that have had a gene replaced or removed.
- **Option B: Clone** - Incorrect, as clones are genetically identical copies of an organism, not necessarily involving gene replacement.
- **Option C: Chimera** - Incorrect, as chimeras are organisms containing cells from two different zygotes, not specifically related to gene replacement.
- **Option D: Surrogate** - Incorrect, as surrogates refer to organisms that carry and give birth to offspring for another organism, not related to gene modification.

5. **Conclusion**: The correct answer to the question is **knockout mice**, as they are specifically defined by the replacement of a desired gene with another gene.

**Final Answer**: Knockout Mice

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