Many gastrointestinal disorders are hereditary or have a genetic predisposition that plays a role in their manifestation. Many of these diseases have been linked to genes discovered recently. Genetic testing is now accessible for several diseases to diagnose them and to detect asymptomatic family members. Although certain genes have been linked to various disorders, the cause of the ailment is yet unknown. These advancements will continue to alter the way doctors diagnose and treat gastrointestinal disorders.
In human physiology, the gastrointestinal tract (GI tract) has two roles: digestion and nutrient absorption, as well as the more difficult work of immunological homeostasis (protecting the body from potentially harmful microbes, while inducing tolerogenic responses to innocuous food, commensals and self-antigens). Because many pathogens enter the body through the intestinal mucosa, it is critical that the lymphoid tissues associated with the gut can deliver efficient immune responses when needed.