DNA and genetic studies
In genetic genealogy studies, Negev Bedouins have the highest rates of Haplogroup J1 (Y-DNA) among all populations tested (62.5%) followed by the Palestinian Arab 38.4%, Ashkenazi Jew 14.6%, and Sephardi Jew 11.9% according to Semino and colleagues.[citation needed] Semitic populations, including Jews, usually possess an excess of J1 Y chromosomes compared to other populations harboring Y-haplogroup J.[98][99][100][101][102] The haplogroup J1, associated with marker M267, originates south of the Levant and was first disseminated from there into Ethiopia and Europe in Neolithic times. In Jewish populations J1 has a rate of around 15%, with haplogroup J2 (M172) (of eight sub-Haplogroups) being almost twice as common as J1 among Jews (<29%). J1 is most common in the southern Levant, as well as Syria, Iraq, Algeria, and Arabia, and drops sharply at the border of non-semitic areas like Turkey and Iran. A second diffusion of the J1 marker took place in the 7th century CE when Arabians brought it from Arabia to North Africa.[98]
Haplogroup J1 (Y-DNA) includes the modal haplotype of the Galilee Arabs[103] and of Moroccan Arabs[104] and the sister Modal Haplotype of the Cohanim, the “Cohan Modale Haplotype”, representing the descendents of the priestly caste Aaron.[105][106][107] J2 is known to be related to the ancient Greek movements and is found mainly in Europe and the central Mediterranean (Italy, the Balkans, Greece).
A study found that the Palestinians, like Jordanians, Syrians, Iraqis, and Bedouins have what appears to be substantial gene flow from sub-Saharan Africa, amounting to 10-15% of lineages within the past three millennia.[108]
According to a 2002 study by Nebel and colleagues[109] the highest frequency of Eu10 (i.e. J1) (30%–62.5%) has been observed so far in various Muslim Arab populations in the Middle East.[110][111] The term “Arab,” as well as the presence of Arabs in the Syrian desert and the Fertile Crescent, is first seen in the Assyrian sources from the 9th century BCE (Eph’al 1984).[112]
In recent years, many genetic surveys have suggested that, at least paternally, most of the various Jewish ethnic divisions and the Palestinians – and in some cases other Levantines – are genetically closer to each other than the Palestinians or European Jews to non-Jewish Europeans.[103]
One DNA study by Nebel found genetic evidence in support of historical records that “part, or perhaps the majority” of Muslim Palestinians descend from “local inhabitants, mainly Christians and Jews, who had converted after the Islamic conquest in the seventh century AD”.[103] They also found substantial genetic overlap between Muslim Palestinians and Ashkenazi and Sephardic Jews, though with some significant differences that might be explainable by the geographical isolation of the Jews or by immigration of Arab tribes in the first millennium.[103]