Rabbi Judy Chessin

While Jews go to great lengths to avoid “racial” stereotypes, science confirms distinctive genetic markers which tie Jewish people to a common Middle Eastern ancestral population.

Studies of DNA sequences indicate that Jewish populations of various Diaspora communities have retained much of their genetic identity despite centuries of living in exile.

Our people’s history of isolation, insularity, in-marrying and inbreeding has created a unique genetic footprint for the Jews.

For instance, in the late 1990s, scientists Karl Skorecki, of the Israel Institute of Technology in Haifa, and Michael Hammer, a geneticist from the University of Arizona at Tucson, revealed that there was indeed a kohein gene — a genetic DNA marker which is found, to this day, in those families who claim to be descended from Aaron the high priest.

Our tradition relates that the Children of Israel were split into three groups: the kohanim (the priestly inner core of the tribe of Levi), then the remainder of the Levites, and then a third group encompassing the other 11 tribes whom we call Israelites.

At the Western Wall during the High Holy Days, researchers gathered DNA from 200 Jewish males, a third of whom identified themselves as kohanim.

Remarkably, no matter whether they were Sephardi (Spanish and Portuguese), Ashkenazi (Eastern European), or Oriental (Middle Eastern, North Africa, Central Asia) Jews, 98.5 percent of those who said they were kohanim shared a genetic marker for a common ancestor: a signature mutation pattern found in only 3 percent of the general Jewish population.

In other words, not just traditions and culture have been handed down along our 3,500-year-old history, but also some common genetic material!

Of course one must approach such scientific data with caution. First, ours has been a long history of mixing with the gene pools of the cultures among whom we found ourselves dispersed. Further, our long, painful history has taught us that grouping people by race, and making assumptions based on physical characteristics, is simplistic, falsely stereotypical, and politically incorrect.

Judaism has to be defined by far more than genetic commonality. It is a faith, a culture, and a people open to converts who thereby modify (and strengthen) the Jewish gene pool.

Judaism views all human beings as equally endowed by our Creator, and therefore shuns any biological predetermination.

Jon Entine spells out this tension in Abraham’s Children: Race, Identity and the DNA of the Chosen People (www.abrahamschildren.net).

He terms DNA a “time machine” that may help us understand how ancestry, along with faith, values, and homeland, have factored in to shape our identity and characteristics as a Jewish people.

The book explores controversial modern suppositions that the very genetic structures that lead to high I.Q. in so many Ashkenazi Jews might also predispose us to the many diseases common to the Jewish people of Eastern European descent.

There are breast or ovarian cancer mutations found only in Jews or descendants of Jews, and more than 19 “Jewish diseases” including Tay-Sachs, Crohn’s, Niemann-Pick, BRCA1 and BRCA2, as well as lactose intolerance and IBS.

It is surmised that, if gene mutations responsible for disease in Ashkenazi Jewry didn’t confer some evolutionary selective advantage, we wouldn’t have survived.

Thus geneticists ponder the possibility that our fabled “Jewish intelligence” might be inbred, that Jewish genetic make-up enhances intelligence so Ashkenazi Jews would survive their very cognitive-demanding occupations.

Since Jews in Europe were not allowed to own land, they were forced to be moneylenders and merchants. Add the Jewish cultural element that glorifies study and attracts intelligent newcomers to the community, and we see the Jewish “bio-cultural feedback loop” which may help explain the disproportionate number of Jews in higher academia.

Finding links between Judaism and DNA may help scientists develop our genetic strengths and mitigate our vulnerabilities.

But most of us will merely look at all of this as interesting information which further reminds us that Judaism is far more than a faith.

Judaism is a belief system, to some degree a blood ancestry, a people, a culture and way of life that is far more mysterious than we will ever grasp.

Whether we are here because of nature or nurture, or both, the fact that the Jewish people have survived and maintained a distinctive genetic identity for more than 100 generations adds nuance to the hopeful prophecy of Jeremiah: “This is the Covenant I will make with the house of Israel after those days, declares the Lord: I will put my Law within them, and I will write it on their hearts. And I will be their God, and they shall be my people (Jeremiah 31:33).”