The main research interest of our laboratory group is to examine the genetic control of autoimmune disease to gain a better understanding of the mechanisms by which immune tolerance is broken. Recently, we generated a mouse model of a human autoimmune disease called APECED, which is classically manifested by an autoimmune attack directed at multiple endocrine organs. This disease is inherited in a monogenic autosomal recessive fashion and the causative gene was identified and is called Aire (for autoimmune regulator). We and others have shown that Aire appears to have the remarkable ability to help drive the expression of self-antigens within the thymus. Thus, the absence of Aire activity in the thymus predisposes to autoimmunity by allowing T cells to escape negative selection against self-antigens. Studies are ongoing to study the development of the specialized cells in the thymus that express Aire.