The Sephardic Jews make up the second largest division of the Jewish population; they have their historic roots in Spain, Portugal and North Africa, as well as due to migrations, in Mesopotamia and Arabia. Sephardic Jews comprise the second largest group in the Jewish population after Ashkenazic Jews that stem from Eastern Europe. Sephardim developed and shared common religious and cultural bonds with their fellow co-religionists from the Iberian/North African Atlantic seaboard to the eastern portion of the Fertile Crescent for at least the last 1,500 years. Sephardim have developed and possess a shared relationship based upon unique religious traditions, collective ideals, customs and ethnicity. Sephardic and Ashkenazic Jews were geographically and religiously separate populations. Because of this separation, these two populations often display significant differences in the incidence of genetic diseases and medical conditions.