Problem: A diverse body of evidence indicates that there is an association among reproductive failure, development, cancer, and autoimmunity. The evidence for the relationship of genes linked to the major histocompatibility complex to these diseases will be evaluated.
Methods: The published results of both experimental studies in animals and of clinical observations in humans will be summarized and analyzed.
Results: Experimental studies in the rat have demonstrated a relationship between the MHC-linked region and growth, development, and susceptibility to chemical carcinogens. Data from other species support these observations. Clinical studies in humans have demonstrated an association between the MHC region and recurrent spontaneous abortions and a variety of other diseases; between recurrent spontaneous abortion and several autoimmune diseases; and between isolated populations and deficiencies of HLA homozygotes.
Conclusions: Genes in the MHC-linked region play an important role in the control of reproduction, growth and development, and susceptibility to a variety of diseases.