Shrinkage of T cell receptor repertoire;Loss of immunological space;Less responsive to immune stimulation/infection and vaccination;Less efficient responses to stress;Decrease ability to cope with environmental challenges, such as reactivation of chronic and new infections;Accumulation of senescent cells in tissue and organs;Reduced proliferative capacity of T cells;Autoimmunity;Immune dysfunctions. The gene discussed is TBXT; the disease is infection.