ABSTRACT
Antigens present on the cell membranes perceive all kinds of environmental information necessary for the proper physiology of the cell. Deletion or blocking of one group of these receptors leads to the disturbance of the corresponding biological process which may lead to manifest clinical disease. Imperfect synthesis of a small amount of an antigen leads to inevitable production of auto-antibodies that may-cross react with the proper perfectly synthesized antigen resulting in the occurrence of auto-immune disease. Complete deletion or blocking of a group of antigens responsible for perceiving the information required for the proper proliferation, of certain cells [by viruses or chemicals or specific antibodies leads to uncontrolled proliferation of these cells. The active genes and their antigens determine the cell responses. Thus, the responses of each individual are decisive. Abnormalities in the genes and/or their antigens lead to morbid physiology that may result in inevitable clinical diseases