Risk of irritable bowel syndrome in first-degree, second-degree and thirddegree relatives of affected individuals: a nationwide family study in Sweden.
IBS aggregates in families, but the familial risk of IBS has only been determined in first-degree relatives and spouses. This nationwide study aimed to determine the familial risk of IBS in first-degree, second-degree, and third-degree relatives and spouses of affected individuals in order to estimate the relative influences of genes and shared family environment.
