The Human Genome Project has facilitated the identification of various genetic regions associated with disease susceptibility. This identification step is important as it yields clues into the pathways implicated in defining disease susceptibility and may uncover important therapeutic targets. Indeed, by performing genome-wide scans, one can identify many genetic loci associated with auto-immune disease susceptibility. However, the odds ratio of each locus is relatively low. Therefore, the limitation of these studies is in the biological translation of the data. This raises the question of how one verifies the true biological impact that each of these genetic variations has on human disease. This book presents an alternative strategy for the identification of various genetic regions associated with disease susceptibility.