Crohn's disease and the Jews.

Several epidemiologic studies of Crohn's Disease (CD) from the northern hemisphere show high rates of the disease among Jews. Israel has absorbed many Jews from those countries and the rates of CD in Israel are lower than in their place of birth. Important, too, among immigrants from the middle east Mediterranean countries, the rates appear to be higher than those in their countries of origin, where the disease is rare. CD has a genetic predisposition, but we physicians cannot ignore the environmental factors.