A skin grafting procedure involves transplant of skin and its underlying tissues to the affected part of the body for wound closure in conditions such as burns, decubitus ulcers, post-surgical wounds, and some types of malignancies. Types of skin graft depends on the source of the skin to be transplanted. An autologous graft came from the patient's non-affected body parts, such as legs. In isogeneic graft, the donor and patient are genetically identical such as a twin. Another human donor could be an allogeneic graft. A pig would be a xenograft (different species).