The research was based on samples from 29 populations, 7 Jewish, categorized into five major divisions: Jews, Middle-Eastern non-Jews, Europeans, North Africans, and sub-Saharan Africans.
Despite large geographic distances between the communities and the passage of thousands of years, far removed Jewish communities share a similar genetic profile.
This research confirms the common ancestry and common geographical origin of world Jewry.
Jewish men from communities which developed in the Near East –- Iran, Iraq, Kurdistan, Yemen -- and European Jews have very similar, almost identical genetic profiles.
These studies showed a very high genetic affinity among present-day Cohanim, indicating that they do have a common paternal ancestor, estimated to have lived some 3,000 years ago.
(See The Cohanim/DNA Connection) The most recent genetic research consists of obtaining DNA samples, and doing laboratory analysis and comparison of the DNA markers on the Y-chromosome –- which is passed from father to son, and on the mt DNA (mitrocondrial DNA) –- which is passed intact from mother to son and daughter.
This genetic anthropology promises to be particularly informative for tracking the history of Jewish populations, and helping to resolve the debate on the origins and migrations of Jewish communities in the Diaspora.
The researchers proposed to answer the question whether the scattered groups of modern Jews can be identified as the descendants of the ancient Hebrews of the Bible, or whether their common ancestry has been diluted through influx of converts and through intermarriage so that little remains of their "Jewish genes." The complex recorded history of dispersal from the Land of Israel and subsequent residence in and movements between various countries in Europe, North Africa and the Middle East is expected to produce a complex pattern of genetic relationships among Jewish populations as well as between them and the non-Jewish peoples among whom they lived.
"Despite their long-term residence in different countries and isolation from one another, most Jewish populations were not significantly different from one another at the genetic level. Nat'l Academy of Science, May 9, 2000) The basis of this new field of population research is the study of the Y-chromosome, which is passed virtually unchanged from father to son.
The results support the hypothesis that the paternal gene pools of Jewish communities from Europe, North Africa and the Middle East descended from a common Middle Eastern ancestral population, and suggest that most Jewish communities have remained relatively isolated from neighboring non-Jewish communities during and after the Diaspora." (M. The rare mutations -– which are changes in the non-coding portion of its DNA –- can serve as markers, which can distinguish peoples.
By studying the genetic signatures of various groups, comparisons can be made to determine the genetic relationships between the groups.
Y-chromosome research of the Jewish people began as an outgrowth of the study of Cohanim –- the Jewish priestly family.