Two thirds of the Arabs in Israel and the territories and a similar proportion of Jews - are descendants of at least three ancestors who lived in the Middle East during the Late Stone Age, about 8,000 years ago. This is according to a new study carried out by an international team of researchers led by Prof. Ariela Oppenheim from the Hebrew and Hadassah University.
About two-thirds of the Arabs in Israel and the territories and a similar proportion of Jews - are descendants of at least three ancient ancestors who lived in the Middle East during the Late Stone Age, about 8,000 years ago. This is according to a new study carried out by an international team of researchers led by Prof. Ariela Oppenheim from the Hebrew and Hadassah University.
In the study, published in the scientific journal "Human Genetics", the researchers traced the history of the Jewish and Arab men by analyzing genetic changes in the Y chromosome - the chromosome that determines the male sex and is inherited from father to son. In principle, all men should have the same sequence of DNA units on the Y chromosome. However, in practice, throughout human history, consistent changes have accumulated in it, due to errors that occurred during its replication.
Since such mutations in DNA occur more or less at a known rate, the Y chromosome can be seen as a kind of clock indicating the time when events occurred in the past. If you compare the Y chromosomes of any two ethnic groups, by the differences you can tell when the common ancestors of both lived.
Unlike DNA tests that aim to identify specific people, DNA analysis of ethnic groups allows researchers to go back in time and trace the genetic history of these groups. "From such tests it is impossible to draw conclusions about the belonging of individual people to one or another ethnic group," says Prof. Oppenheim.
Dr. Marina Fireman and Dr. Deborah also participated in the research, which was carried out by doctoral student Almot Navel.
Filon from the Hebrew University and Hadassah and Dr. Mark Thomas and his colleagues from University College London.
The results of the research, says Prof. Oppenheim, "support the historical record that the Arabs are descendants of the ancient population of the land, and that a significant number of them are Jews who converted to Islam." The great genetic closeness between the Jews and the Arabs was also reflected in a recently published study, in which Prof. Michael Hamer from the University of Arizona, Prof. Batsheva Buna-Tamir from Tel Aviv University, Prof. Oppenheim and others examined DNA changes that occur extremely rarely. They discovered that the Y chromosome of the Palestinians from Israel and the territories is so similar to that of the Jews that it is almost impossible to distinguish between the two.
In the current study, Oppenheim and her colleagues focused on the Arabs. They examined 143 Palestinians from Israel and the Palestinian Authority, and 119 Ashkenazi and Sephardic Jews, and unlike the previous study, they also tracked DNA changes that occur more frequently, approximately one in a thousand births. This is how they discovered that Jews and Arabs have common ancestors who lived right up to the last thousands of years.
The picture of the family tree emerging in the research shows that the origin of the Arabs and Jews is at least in three main ancient races. The Y chromosome of the Jewish and Palestinian men today is therefore imprinted with signs from the ancient ancestors who lived tens of thousands of years ago, and whose descendants inhabit the land today.
The research also alludes to the migration routes of modern man, who developed in Africa about 150 thousand years ago and migrated from there to the whole world through the Middle East. About two-thirds of the Arabs and Jews examined, it turns out, are descendants of one ancestor, who originated in sub-Saharan Africa about 100 years ago. Another 20% of the subjects are descendants of another, younger ancestor, who also originated in Africa. The origin of about 15% of the subjects is in a lineage that apparently developed in Central Asia (after splitting from the main branch in Africa) and reached the Middle East region.
Considering the limited geographical area of Israel and the territories, the researchers were surprised to discover that some of the Palestinians in the West Bank have a genetic uniqueness that is expressed in a relatively high frequency of certain genetic signs, which indicates that they are descendants of people who have lived there for at least hundreds of years. The genetic uniqueness of the Palestinians from the West Bank was further sharpened when the researchers tested genetic defects that could cause a blood disease called thalassemia. 50% of the mountain dwellers tested carried the same defect, compared to, for example, 15% of Gaza residents.
Many branches branch off from the evolutionary tree trunks drawn by the researchers - each branch represents a different Arab or Jewish individual. The branches intertwine as an inseparable mosaic, with the exception of one branch, which the researchers called the "Arab branch". About a third of the Arabs examined in the study were found to belong to him. The researchers do not know the origin of the Arab branch, but since the genetic diversity in it is small, they assume that it probably split from the main race only in the last few thousand years.
The first clue to the origin of the Arab branch was given in a study published this year, in which it was discovered that the genetic markers present in the branch are also found in Arab Yemenis from the city of Daramaut, which raises the possibility that the founding ancestors of the branch are Arab tribes that migrated to the region in the first millennium AD. The research on the matter is still ongoing, and Oppenheim and her colleagues are now examining additional non-Jewish populations from the area and hope to discover the origin of the Arab branch.
