History and Genetics: Commonality of origin

Bene Israel, India, 1901-1906

Part II

The issue of the common origin of the Jews has been greatly illuminated by genetic study.  Jews from the ancient Land of Israel were dispersed into the wider Diaspora communities, through a whole series of events including emigration, exile and long-term business travel that resulted in the founding of far-flung Jewish communities. Genetic evidence has tended to provide a number of indications of elements common to the main population groups of the Jewish people, Ashkenazim, Sephardim (by which we refer to the Spanish Portuguese Jews and their descendents) and Middle Eastern Jews.  The method of coalescence has been used to determine that the particular mutations causing certain diseases occurred some 2000 years ago, when the main body of the Jewish population was still in the Land of Israel. This is the case with Familial Mediterranean fever and with the BRCA1 and 2 genes that give rise to breast and ovarian cancer.  One of these mutations has been found among Jews from all over the world, including Bene Israel and some Hispanics who may be descendents of Conversos.  Again, such features indicate the common genetic origin of the Jews.  All this is in confidence with our understanding of the common historical origin of the Jewish people.[1] Investigation of the Y chromosome has shown that most Diaspora Jews are descended from a small group of men who at some time lived in the Middle East.  In this case, the resemblance of these men to other Middle Eastern males indicates the likelihood that the Jewish community did for the most part in fact emanate from Middle East antiquity.[2]

The Jewish HapMap Project has found that Ashkenazic, Sephardic and Syrian Jews were more similar to one another than to Middle Eastern, Iranian and Iraqi Jews.  This genetic split seems to have occurred approximately 2500 years ago.  Over the last 2000 years the European and Syrian populations were formed by people expelled from or who voluntarily left Palestine as well as by non-Jews who joined the Jewish people, a phenomenon well-known to have occurred during Greco-Roman antiquity.