Yemenite Jews - DNA Testing

DNA Testing

DNA testing between Yemenite Jews and various other of the world's Jewish communities shows a common link, with most communities sharing similar paternal genetic profiles. Furthermore, the Y-chromosome signatures of the Yemenite Jews are also similar to those of other Middle Eastern populations.

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. 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.

One point in which Yemenite Jews appear to differ from Ashkenazi Jews and most Near Eastern Jewish communities is in the proportion of sub-Saharan African maternally-transferred gene types (mitochondrial DNA, or mtDNA) which have entered their gene pools. One study found that some Arabic-speaking populations—Palestinians, Jordanians, Syrians, Iraqis, and Bedouins—have what appears to be substantial mtDNA gene flow from sub-Saharan Africa, amounting to 10-15% of lineages within the past three millennia. In the case of Yemenites, the average is actually higher at 35%. Of particular historic interest might be the finding that with almost no exceptions the sub-Saharan gene flow was exclusively female, as stated in this excerpt from the study:

We have analyzed and compared mitochondrial DNA variation of populations from the Near East and Africa and found a very high frequency of African lineages present in the Yemen Hadramawt: more than a third were of clear sub-Saharan origin. Other Arab populations carried ∼10% lineages of sub-Saharan origin, whereas non-Arab Near Eastern populations, by contrast, carried few or no such lineages, suggesting that gene flow has been preferentially into Arab populations. Several lines of evidence suggest that most of this gene flow probably occurred within the past ∼2,500 years. In contrast, there is little evidence for male-mediated gene flow from sub-Saharan Africa in Y-chromosome haplotypes in Arab populations, including the Hadramawt. Taken together, these results are consistent with substantial migration from eastern Africa into Arabia, at least in part as a result of the Arab slave trade, and mainly female assimilation into the Arabian population as a result of miscegenation and manumission.

Yemenite Jews, as a traditionally Arabic-speaking community of local Yemenite and Israelite ancestries, are included within the findings for Yemenites, though they average a quarter of the frequency of the non-Jewish Yemenite sample. In other Arabic-speaking populations not mentioned, the African gene types are rarely shared. Other Middle Eastern populations, particularly non-Arabic speakers—Turks, Persians, Kurds, Armenians, Azeris, and Georgians—have few or no such lineages.

A study performed by the Department of Biological Sciences at Stanford University found a possible genetic similarity between 11 Ethiopian Jews and 4 Yemenite Jews who took part in the testing. The differentiation statistic and genetic distances for the 11 Ethiopian Jews and 4 Yemenite Jews tested were quite low, among the smallest of comparisons that involved either of these populations. Ethiopian Jewish Y-Chromosomal haplotype are often present in Yemenite and other Jewish populations, but analysis of Y-Chromosomal haplotype frequencies does not indicate a close relationship between Ethiopian Jewish groups. It is possible that the 4 Yemenite Jews from this study may be descendants of reverse migrants of African origin, who crossed Ethiopia to Yemen. The result from this study suggests that gene flow between Ethiopia and Yemen as a possible explanation. The study also suggests that the gene flow between Ethiopian and Yemenite Jewish populations may not have been direct, but instead could have been between Jewish and non-Jewish populations of both regions.