June 10, 2010

Jewish Origins Confirmed Through DNA

New studies have found that Jews share a genetic bond with Cypriots and Druze and verifies the Jewish Diaspora maintained a strong DNA continuity despite its long separation from the Middle East, according to scientists on Wednesday.

The work is part of a larger exploration into human migration based on groups of tiny differences in genetic codes.

"We found evidence that Jewish communities originated in the Near East," said molecular scientist Doron Behar of the Rambam Health Care Campus in Haifa, Israel.

Behar, who led the investigation that gathered experts in eight countries, said: "Our genetic findings are concordant with historical records."

The researchers analyzed genetic samples from 121 people living in 14 Jewish communities across the world and compared them with those from 1,166 people in 69 non-Jewish populations, including the "host" country where there was a Jewish community.

Throwing another dataset into the mix, the researchers added analyses of 16,000 samples of the Y chromosome -- which only males have -- and of mitochondrial DNA, which is handed down through the maternal line.

What the scientists were looking for were combinations of markers called single nucleotide polymorphisms (SNPs). SNPs are single changes in the genome that cluster in distinctive patterns among humans that live together in groups over thousands of years. The patterns are a useful pointer of how ethnicities developed through geographical isolation or social clustering.

The study, as expected, confirmed the Middle Eastern, or Levantine, origins of Jews as documented in ancient Hebrew scriptures. This lineage is clearly visible in communities today, ages after the Jews were expelled from Israel.

The study also revealed, however, that most Jews were "genetically closer" to each other than their non-Jewish neighbors. It also revealed genetic ties between globally dispersed Jews and non-Jewish populations in the Middle East.

Diaspora Jews, tightly bound by social, cultural and religious traditions, have generally maintained a strong genetic continuity, although there has also been an induction of DNA to greater or lesser degree from the host population, the research showed.

"Jewish communities seem to have a continuity with the Levantine gene pool, but even with the Jewish communities, you still see how they tend towards the host population," said Behar.

There were exceptions to this key finding, though, as Dr Behar explained.

He said that his research revealed that Ethiopian and Indian Jewish communities were genetically closer to their neighboring non-Jewish populations, which could be partly due to a greater degree of genetic, religious and cultural crossover that took place when the Jewish communities in these areas became established.

In non-Jewish populations, the SNP clusters confirmed a close relationship among Bedouins, Jordanians, Palestinians and Saudi Arabians. The patterns in Egyptians, Moroccan, Berber and Yemenite samples, though, were more similar to populations south of the Sahara.

Dr Behar says the data from this study could aid future research into the genetic basis of diseases that are more prevalent in the Jewish population.

Previous SNP research of this type has been done in the so-called HapMap Project.

It has helped to cast light on the "Out of Africa" scenario, which places that all anatomically modern humans descended from ancestors that ventured from an African homeland around 50,000 years ago and colonized the world.

To avoid being drawn into a debate over false concept of race, scientists say the SNP clusters are not a pointer to any differences in human health, intelligence or ability.

He added he would be troubled if his research became misused for genetic profiling, such as in the "who is a Jew?" debate which touches on who has automatic right of citizenship in Israel.

"It is very important for me to mention here that as a scientist, genetics has nothing to do with the definition of the Jewish identity," Behar told AFP.

"Judaism is a plural religion. Anyone in the world can decide one day that he wants to convert to Judaism and in that case of course genetics has no meaning... genetics would not be able to prove or disprove the Jewish identity of an individual," he noted.

The research is published in the British journal Nature.


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