In addition to a clear genetic disposition, environmental factors and viral infections are
thought to play a role in the pathogenesis of autoimmune diseases such as type I diabetes
or multiple sclerosis (MS). This article will explore, by use of paradigms developed in a
transgenic mouse model, why it has been so difficult to prove a causative association
between viral infections and autoimmunity. Potential pathogenetic mechanisms and their
impact on devising the best strategy to prove such an association will be discussed. These …