Genetic studies on Jews are part of the population genetics discipline and are used to analyze the chronology of Jewish migration accompanied by research in other fields, such as history, linguistics, archaeology, and paleontology. These studies investigate the origins of various Jewish ethnic divisions. In particular, they examine whether there is a common genetic heritage among them. The medical genetics of Jews are studied for population-specific diseases. Studies of autosomal DNA, which look at the entire DNA mixture, show that Jewish populations have tended to form relatively closely related groups in independent communities with most in a community sharing significant ancestry. For populations of the Jewish diaspora, the genetic composition of Ashkenazi, Sephardi, and Mizrahi Jewish populations shows significant amounts of shared Middle Eastern ancestry. According to geneticist Doron Behar and colleagues (2010), this is "consistent with a historical formulation of the Jewish people as descending from ancient Hebrew and Israelites of the Levant" and "the dispersion of the people of ancient Israel throughout the Old World". Several Jewish groups also show genetic proximity to Lebanese, Palestinians, Bedouins, and Druze in addition to Southern European populations, including Cypriots and Italians. Jews living in the North African, Italian, and Iberian regions show variable frequencies of admixture with the historical non-Jewish population along the maternal lines. In the case of Ashkenazi and Sephardi Jews (in particular Moroccan Jews), who are closely related, the source of non-Jewish admixture is mainly southern European. Behar and colleagues have remarked on an especially close relationship between Ashkenazi Jews and modern Italians. Some studies show that the Bene Israel and Cochin Jews of India, and the Beta Israel of Ethiopia, while very closely resembling the local populations of their native countries, may have some ancient Jewish descent.