Donated Hair for Transplantation?

why can’t someone use another person’s hair if the blood types match and he is willing to donate his or her hair for you

Good question. When you think about hair you think of that stuff that grows on top of your head. Hair on the top of your head is dead as it exits the skin. The frozen Eskimos and ancient Egyptians in the tombs still had hair after thousands of years. Of course, it is dead. Now when I think about hair, I think of an organ. Each follicular unit of hair has blood vessels, glands, nerves, skin, and fat. It takes all of this plus a growth center and the right genes and nutrition to make hair grow. Since by definition hair is an organ, transplanting the hair from someone else is like transplanting a heart, kidney, lung, etc. These organs are rejected by a person unless the recipient is given drugs to suppress rejection. If you had a twin, then hair from that twin with the exact same genetic blueprint would give you a successful transplant. We did that exact process on identical twins and it worked wonderfully. The usual problem is that when one twin has balding, so does the other.