Kidney transplant from a mother to son is known as
**Core Concept**
The question is testing the understanding of the specific type of kidney transplant that occurs between a mother and her child. This is a classic example of a living-related organ transplant, where a donor organ is obtained from a living person, usually a family member.
**Why the Correct Answer is Right**
The correct answer is based on the concept of consanguineous relationship in transplantation. In this context, the mother is the donor, and the son is the recipient. This type of transplant is often referred to as a "mother-to-child" or "parent-to-child" transplant. The immune system of the recipient (son) is less likely to reject the donated kidney from his mother due to the sharing of human leukocyte antigens (HLA).
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not specify the relationship between the donor and the recipient. While it is a type of living-related transplant, it does not accurately describe the mother-son relationship.
**Option B:** This option is incorrect because it refers to a transplant between genetically unrelated individuals, which is not relevant to this question.
**Option C:** This option is incorrect because it refers to a transplant between a donor and a recipient who are not related by blood, which is not the case in this scenario.
**Clinical Pearl / High-Yield Fact**
It's essential to remember that living-related transplants are often preferred over cadaveric transplants due to the reduced risk of rejection and improved graft survival. Additionally, the sharing of HLA between family members can significantly reduce the risk of graft rejection.
**Correct Answer:** A. **Isograft**