Loci, Minor Histocompatibility

Medical Condition:
Loci, Minor Histocompatibility

Genetic loci responsible for the encoding of histocompatibility antigens other than those encoded by the major histocompatibility complex. The antigens encoded by these genes are often responsible for graft rejection in cases where histocompatibility has been established by standard tests. The location of some of these loci on the X and Y chromosomes explains why grafts from males to females may be rejected while grafts from females to males are accepted. In the mouse roughly 30 minor histocompatibility loci have been recognized, comprising more than 500 genes.