Minor Histocompatibility Complex

In addition to the (MHC), there are other genes that encode antigens that may be responsible for rejection. This is shown by several observations;

• Rejection of skin grafts between MHC identical mice
• Development of severe graft versus host disease in bone marrow transplantation between MHC identical siblings.

Obviously structures other than MHC can be recognised by T cells to activate the immune response. Many of theses genes have been identified and are lumped together as the minor histocaompatibility complex (MiHC).