Jews and Arabs are 'genetic brothers'

Jewish heritage has been maintained

They may have their differences but Jews and Arabs share a common genetic heritage that stretches back thousands of years.

The striking similarities in their biology have just been revealed in a study of over 1,300 men in almost 30 countries worldwide.

Scientists compared the men's Y chromosomes, the tiny structures within cells that carry the genetic instructions that tell a developing foetus to become a boy.

The comparison also showed that Jews have successfully resisted having their gene pool diluted, despite having lived among non-Jews for thousands of years in what is commonly known as the Diaspora - the time since 556 BC when Jews migrated out of Palestine.

Genetic signatures

Throughout human history, alterations have occurred in the sequence of chemical bases that make up the DNA in the Y chromosome, leaving variations that can be pinpointed with modern genetic techniques.

Related populations carry the same specific variations. In this way, scientists can track descendants of large populations and determine their common ancestors.

The study, published in the Proceedings of the National Academy of Sciences, found that Jewish men shared a common set of genetic signatures with non-Jews from the Middle East, including Palestinians, Syrians, and Lebanese.

These signatures were significantly different from non-Jewish men outside of the Middle East. This means Jews and Arabs have more in common with each other, genetically speaking, than they do with any of the wider communities in which they might live.

Good opportunity

Dr Mark Jobling of Leicester University, UK, one of the authors of the new study, told the BBC: "The kind of DNA we have used to analyse this question is the human Y chromosome. This represents only 2% of our genetic material and it is passed down from father to son.

"This makes it particularly interesting to use in a study of Jewish populations because Jewishness is passed down from the mother to children - it is maternally inherited. So using a paternally inherited piece of DNA gives us a good opportunity to see the signal of mixture with other populations if this has occurred.

"The fact that we don't see it suggests that after the Diaspora these populations really have managed to maintain their Jewish heritage.

Dr Jobling dismissed the idea that the study could have any political implications. "It seems that in many of these situations where groups are in conflict with each other they are likely to be pretty much genetically indistinguishable, and this factor, to the peoples involved in these conflicts, clearly isn't the point and isn't likely to change their behaviour very much."