Genetics

There are conflicting opinions on whether IBS has a genetic component. Some argue that IBS does not truly run in families, as IBS in relatives may be more due to learned behaviors and environmental exposure than to genetics. Twin studies have shown that having a parent with IBS is a stronger predictor of having the condition than having a twin with IBS (29). But, some genetic susceptibility may be present with a connection to mood disorders, such as anxiety (30), and genetic components have also been found for constipation (28).