Allograft

An allograft, also known as an allogenic transplant, refers to a medical situation when cells, tissues, and organs used in operations have been sourced from a genetically nonidentical member of the same species. This is common with transplants when tissue and organ are taken from a donor and transferred to a recipient, most often someone unrelated to the donor, although obviously of a compatible blood type. This is common practice with skin transplants and also transplants of corneas, hearts, livers, kidneys, and bone and bone marrow, although transplants for the last often come from relatives.

Isografts are when tissue or organs are transplanted from a genetically identical donor, such as an identical twin, with autograft being when tissue is transplanted from one site on a patient to another, such as for skin grafts after melanomas and so forth caused by skin cancer. There can also be xenografts, where transplants are made from another species.