Which transgenic animal has been given human genes for organ transplantation into humans without risk of rejection ?

Options

A. (a) Cow
B. (b) Sheep
C. (c) Goat
D. (d) Pig

Answer

**Step-by-Step Solution:**

1. **Understand the Concept of Transgenic Animals**: Transgenic animals are those that have had foreign genes inserted into their genome. This process is often used to study gene function and to produce proteins for pharmaceuticals, but it can also be applied in organ transplantation.

2. **Identify the Purpose of the Transgenic Animal**: The question specifically asks about a transgenic animal that has been modified to have human genes for the purpose of organ transplantation into humans. This is a process known as xenotransplantation.

3. **Recognize the Challenges of Xenotransplantation**: One of the major challenges in xenotransplantation is the risk of organ rejection by the human immune system. To minimize this risk, scientists look for animals whose genetic makeup is similar to that of humans.

4. **Determine the Most Suitable Animal**: Among various animals, pigs have been identified as suitable candidates for xenotransplantation. Research shows that the pig genome shares about 84% similarity with the human genome, making them a prime candidate for organ transplantation.

5. **Conclude with the Correct Answer**: Given the information about the similarity between human and pig genomes, the transgenic animal that has been modified with human genes for organ transplantation is the pig. Therefore, the correct answer is the "transgenic pig."

**Final Answer**: The transgenic animal that has been given human genes for organ transplantation into humans without risk of rejection is the **transgenic pig**.

---