- The H4b minor histocompatibility antigen is caused by a combination of genetically determined and posttranslational modifications. Yadav, R., Yoshimura, Y., Boesteanu, A., Christianson, G.J., Ajayi, W.U., Shashidharamurthy, R., Stanic, A.K., Roopenian, D.C., Joyce, S. J. Immunol. (2003)