That difference is actually a survival benefit: The combination of two individuals' different MHC (major histocompatibility locus) genes gives their offspring an advantage in beating back disease ...

Although elegant, this model was not verified. Hybrid resistance was mapped to several putative Hh loci located close to MHC class I genes, but no corresponding genes or antigens were ever found.

By offering exquisite antigen specificity and sensitivity, it is suitable for basic and clinical study in a number of applications including cancer prevention, cancer therapy, cell and gene therapy, ...