Family segregation analysis of inheritance of human minor histocompatibility antigen

Disparities in minor histocompatibility antigens (mHAs) between HLA-identical donor and recipient pairs often cause graft-versus-host disease (GVHD) or graft rejection. Minor HAs are thought to be peptides that are associated with specific major histocompatibility complex (MHC) molecules and are presented to specific T cells. Despite the importance of mHAs in constructing a strong immunological barrier following tissue transplantation, little information on mHAs in humans is available. We have already reported establishment of the DR9-restricted mHA-specific CD4+ cytotoxic T cell (CTL) clone "A-6." To investigate the chromosomal localization of the gene encoding the mHA peptide recognized by clone A-6 in context with DR9, we performed a family segregation analysis. We concluded that the mHA-encoding gene was transmitted from parent(s) to some offspring.