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A Case for Genetic Jewishness

In the book Legacy, geneticist Harry Ostrer argues that Jewishness is biological, not just cultural

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For a Jewish genetics researcher, being told in print that “Hitler would certainly have been very pleased” by your work can’t be pleasant. But that’s what happened in 2010 to Harry Ostrer, a geneticist at the Albert Einstein College of Medicine, when he and his colleagues published a study showing that Jews in three different geographical areas had certain collections of genes that made them more biologically similar to one another than they were to non-Jews in the same regions. The work also showed that Jews around the world could trace their ancestry to a group of people who lived in the Middle East 2,000 years ago; that meant, however, that certain genetic signatures could be used to identify Jews, indicating that Jews share a common biological identity beyond their religious affiliation—which is what inspired the Hitler crack.

Jews, the work of Ostrer’s group and another team found, are as closely related genetically as would be expected for typical fourth or fifth cousins. “I would hope that these observations would put the idea that Jewishness is just a cultural construct to rest,” Ostrer told Science magazine at the time.

Ostrer’s new book, Legacy: A Genetic History of the Jewish People, goes further, making a convincing case that there is, in fact, a biological basis for Jewishness: “[Jews] can be said to be a people with a shared genetic legacy,” he writes, “although not all Jews share the same genes, nor is having part of that legacy a requirement for being Jewish.” Although Ostrer gathers the evidence succinctly, the book is unlikely to sway his most ardent critics, scientists such as Tel Aviv University’s Shlomo Sand, the historian who invoked Hitler’s memory to describe Ostrer’s research. But that may not be Ostrer’s main goal. For non-scientists who are curious about their genetic heritage, the book will open up rich avenues of exploration, along with a history lesson about the development of modern genetics—as well as provocative discussion about how the choices Jews are making today about their mates and their children will affect the future of Jewish genetics: Even as Ostrer argues for Jews’ common biological history, he sees the future of Jewish genetics going in a very different direction.

Over the past century, the sometimes-arcane debate within the scientific community over whether Jewishness is biological or cultural has been almost Talmudic, with various groups interpreting the data in different ways. Jews have higher IQs than others, some research has found, suggesting a genetic link among Jews; or maybe, other research has countered, that’s only because Jews have learned to take IQ tests better. Jews have a higher incidence of mental illness, or maybe only certain kinds of mental illness, depending on the study. In many cases, when researchers thought they had found some real biological trait more common among Jews, they realized later that they had “keys under the streetlight syndrome”—“ascertainment bias,” in scientist speak: If you’re only looking under the streetlight for your keys, that seems to be the only place you ever find them. In other words, when scientists start their research by looking for more evidence to confirm something they already think is true, they can be less likely to take other explanations into account, making their conclusions misleading.

The ability to sequence genomes quickly and more and more cheaply has accelerated the field in recent years, leading to new theories. Sand, for example, argues that today’s Jews are all descended from Khazars, an idea Ostrer finds unsupported by the evidence, as he explains in the book. And for some researchers, the question of “who is a genetic Jew” is less important than “who has Jewish genetic diseases,” since a major part of what Jews think about in terms of their genes involves Canavan, Gaucher, and Tay-Sachs diseases, and risk factors such as BRCA, a genetic mutation linked to breast cancer. (It’s not just Jews who are wondering what’s in their genes, of course, as books such as Robert Klitzman’s Am I My Genes? make clear.)

In Legacy, Ostrer traces a century of physical anthropology and genetic research, with all of its twists and turns, and sometimes heated political battles. Ostrer’s book is very much focused on the science and scientists. He explains that he abandoned his plans to write about patients and genealogists in favor of telling the stories of “scientists and physicians who made the discoveries.” The approach allows him to follow the science more closely, although it sacrifices some of the narratives that may connect with readers. Ostrer clearly knows his subject inside and out, and it shows, but readers may find themselves wishing he had replaced some of the details about experiments and genetic theories with stories of some of the people with these genetic traits.

Ostrer takes plenty of opportunities to tie history and culture to science, however. English majors may remember Daniel Deronda, George Eliot’s last completed novel, whose protagonist becomes Jewish after rescuing a Jewish singer from suicide. Reading Eliot’s book was a life-changing event for one of the main subjects in Ostrer’s book, physical anthropologist Joseph Jacobs. In the 1880s, Jacobs, who became editor of The Jewish Encyclopedia, used knowledge gleaned from an apprenticeship with Charles Darwin’s cousin, Francis Galton, to study physical characteristics of Jews and conclude that they were, in fact, a race. Based on Jews’ physical characteristics, Jacobs wrote in The Jewish Encyclopedia: “The remarkable unity of resemblance among Jews, even in different climes, seems to imply a common descent.” And yet Jacobs’ claims were opposed to those of Maurice Fishberg, his contemporary. Somehow, despite saying that “one can pick out a Jew from among a thousand non-Jews without difficulty,” Fishberg rejected the concept of a Jewish race. There had been too much intermingling with gentiles, he said.

Neither Jacobs nor Fishberg, however, had the genetic tools necessary to dive deep into the molecular underpinnings of genealogy. (In fact, they both died decades before the discovery of DNA.) In the last two decades, scientists have used the male-only Y chromosome to speculate about the origins of Cohanim, at one point excitedly announcing that they had found evidence that the founder of this genetic line had lived during Temple days. But Ostrer notes that this enthusiasm “has been tempered by other observations,” just as the work of other scientists has been woven into a tapestry that none of them could have imagined in their time.

Ostrer’s careful and understated analysis of the evidence makes his arguments convincing. He is nuanced and doesn’t pretend that science has all of the answers about how Jews should feel about their identity. “The stakes in genetical analysis are high,” he writes, noting that they touch “on the heart of Zionist claims for a Jewish homeland in Israel.” Admixture with non-Semitic groups, in fact, “may absolve Jews from Christ-killing,” he writes. And he rejects the idea that his and others’ work would have pleased Hitler: “We were not seeking to develop a hierarchy of human groups nor attempting to eliminate individuals on the basis of their having ‘undesirable’ genes or traits, as the Nazis had.”

So, if Jews have common genetic markers, can a gene test (like the ones already being marketed) really tell you if you’re Jewish? “[T]here is no rigorous genetic test for Jewishness, nor would the geneticists who have conducted studies in recent generations propose that one should be created,” Ostrer writes. “Moreover, such a test would not replace the religious definition of who is a Jew.” The Israeli Law of Return, for example, doesn’t have a genetic requirement.

And even if such a test existed, it would need constant updating. Because even though Jews have maintained certain common genetic traits for millennia, those traits are likely to change at a rapid pace in the coming years. Jews are intermarrying at increasing rates. One of the genetic studies Ostrer quotes found that about 30 to 50 percent of couples that include Jews are now interfaith, compared to one in 200 couples per generation, on average, over much of human history. And people with a predilection for diseases that might have killed them before they passed on their genes are living longer, thus keeping certain traits in the Jewish gene pool at higher rates than would be expected from natural selection over time. Today’s Jews “are making spousal choices and using genetic information for disease treatment, disease prevention, and embryo selection to determine who future Jews will be,” Ostrer writes.

Jewish genetics, in other words, will change over time just as Judaism’s spirituality, social values, and culture have changed over the centuries. All of those characteristics help answer the question of what makes someone Jewish, but what made someone Jewish a thousand or even a hundred years ago is likely not how someone asking that question in a hundred years will answer it. Ostrer quotes Albert Einstein, who said in 1955 that his “relationship to the Jewish people has become my strongest human tie.” He also wrote: “In the philosophical sense there is, in my opinion, no specific Jewish outlook.”


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marjorie ingall says:

Terrific, lucid piece. It’s so hard to write clearly and fluidly about science for a lay audience! I’m adding Retraction Watch to my RSS feed and looking forward to reading more of Oransky’s work. 

littlebadwolf says:

nature seems to have its ways of compensating and balancing.  could it be that the current wave of ‘intermarriage’ is purposed to to amplify the gene pool which was narrowed dangerously by the loses of the holocaust, and will ease back when people rejoin us with knowledge of their parital jewish roots?

Zainab632 says:

I am so pleased for Shlomo Sand. Thank you, Prof. Ostrer.

    Jacob Arnon says:

    Are you?  you must not know much about historiography, then.  

      Zainab632 says:

      Don’t patronize me, I’ve been researching  Jewish history for the last 35 years. The one who doesn’t know much but has a lot of chuzpah is Shlomo Sand.

      Natan79 says:

      Sand is a crook. Would you like to have brain surgery done by a man of Sand’s outlook?

This: “scientists such as Tel Aviv University’s Shlomo Sand, the historian” is misleading as it mixes up the reader. Sand is not a scientist in the sense that a biologist or geneticist is.  Sand has no professional or academic qualification to deal with the science in this book, unless you consider him a scientific Communist, which he mahy be.

    Rebecca Klempner says:

    I enjoyed the piece, however, the summary of Daniel Deronda’s plot is inaccurate (to accurately describe it would probably involve a spoiler).
    The biggest difference between Dr. Ostrer and Dr. Sand is that Dr. Ostrer bases his claims on actual evidence, whereas Dr. Sand’s arguments have more holes than a matzah and lack substantial evidence.

LazerBeam007 says:

This is the most useless, uninformative article of its kind ever written on the subject.  Don’t waste your space or my time on such dreck!  Let this “scientist” sell his book on his own time.  If the topic is over the head of the author, find a another author better suited to the task.  The most interesting question posed by the Zion Deniers is whether European Jews are descendants of the Kazars, and therefore, have no historical claim on or right of return to Eretz Yisroael.  The Zion Deniers are probably an unholy alliance of ultra-right fascists and ultra-left loonies whose anti-Semitic passions are stirred up and disinformation campaigns paid for by Saudi Arabia’s Wahhabi Lobby.  This article could have taken on this issue directly, but instead discovered and concluded the obvious. Thanks for bupkis.

    xmontrealer says:

    Oy! First the “Wahhabi Lobby” sounds like a great title for a country Western song.
     Second, even though DN study after DNA study, and Ostrer work is no exception, all show that most Jews have genetic ties to the Middle East, this won’t stop writers like Sand and Koestler from continuing to have avid fans among those who are bound and determined to find any basis with which to discredit Jews in general, and especially Jewish ties to Israel.

    Preaching to the choir hear won’t really change much.

      marjorie ingall says:

      I think “Wahabi Lobby” sounds like a deck on the Love Boat. 

      Jacob Arnon says:

      “Preaching to the choir hear won’t really change much.”

      All true science “preaches to the choir” that is to those who accept the scientific method.

      Shlomo Sand from what I have read by him doesn’t seem to accept the scientific method. His book is more the product of post structuralist ideology than of historiographical methodology.  

        xmontrealer says:

        Thank you for your interest in mu post. I agree that Sand’s “theories” as well as the approval of his supporters, fly in the face of scientific method. The author of the article does touch on this. I simply obejected to the view of the poster who seemed to want to article to dwell on this, which would be misplaced. Ostrer’s whole study demolishes the theory, so if that won’t convince the Sands of denial, nothing will.

        But I do have to object to your introductory statement in that revolutionary scientific finds such those of Galileo, Copernicus, and Darwin flew in the face of the existing “science” which, at the time, was awash with religious chazerai.

    paul delano says:

    The Khazar ‘theory’ has been discredited decades ago by DNA and genetic testing.  Only certified morons and/or Nazi retards continue to parrot this fiction.

Jacob Arnon says:

I liked the article very much. Jews are a people and there always is a genetic component to peoplehood, though it need not be central. (The American people have a common heritage though not a common genetic pool.)

In any case, I wouldn’t letter Hitler define Jewishness any more than I would let him define vegetarianism even though he was a vegetarian.  (All you vegetarians out there take note.)

    Jacob Arnon says:

    “In any case, I wouldn’t letter Hitler define Jewishness any more than I would let him define vegetarianism even though he was a vegetarian.”
    Should read:  “In any case, I wouldn’t let Hitler define Jewishness any more than I would let him define vegetarianism even though he was a vegetarian.”

Brothers and sisters! The global economy IS GOING TO COLLAPSE IN 5 DAYS! THIS IS THE WARNING CALL! 

paul delano says:

Leftists like Sand have to deny the genetic proof of Jewish homogeneity because it destroys everything their academic ‘credentials’ rely upon.

    Jacob Arnon says:

    Not only that Sand seems afraid to own up to the fact that Jews are a people with a similar genetic core.

    He is one of those Jews who has been made afraid by Nazism to be a Jew.  Koestler had already said when he wrote The Thirteenth Tribe that his aim was to counter Nazi anti-Semitic ideology. 

    He really believed (wrongly) that when antisemites said “Semitic” they meant that they hated  all Semites including Arabs. This has been shown to be false. Hitler had no  problem eating with the Mufti of Jerusalem. He even made him an “honorary Aryan.”

      xmontrealer says:

      Jacob, that’s a bad analogy, I’m afraid. Amazingly, Hitler put Arabs below Jews on his racial “totem pole”. While his meeting with the Mufti is real enough, his refusal to put our a public announcement in support of Arab nationalism had a certain degree of political pragmatism. in that he didn’t want to further aggaravate tensions with Britain in the region, but he also had grave misgivings about the quality of Arabs as serious military allies. While there can be no doubt that Hitler held the Mufti in high regard, calling him his “Middle Eastern Fuhrer”, and his propagandizing was worthy of praise by the master Goebbels himself, it would be unfair to paint Hitler as an admirer of Arabs, as many Britons were.

      While it is more than a little uncomfortable to sound as if I am defending Hitler, it is important to note that his maniacal Jew hatred was not based on the method Jews used to worship specifically. It was based on, first, racial inferiority, but more practically, on the alledged economic and political significance of the Jews. In  these facets, it was easy to find common cause with Islam. These theme still run rampant today in Moslem countries, and it is no coincidence that the word “Iran” is the Farsi word for “aryan”.

        genelevit says:

        Nazi’s racial “theory” had many “holes” in it. For example they defined Croats as “Aryans” while Serbs as “subhumans”.  Genetically, however,  they are the same people.   

Uzi_86 says:

A review of Sand’s newest creation: “The invention of Israel”
It’s quite positive (no surprise coming from Gurvitz). The book hasn’t been translated into English yet, but would still be curious to hear Tablet’s take on the Hebrew version, so I don’t only have Gurvitz’s take to go on.

And as for the article, I agree that genetics are nice to know (from both a medical and personal perspective), but they should not be used as the core of defining the Jewish people. 

This article is no news for me. I really knew that we were a race when I realized that one uncle of mine looked like Paul Muni and another was identical to Tony Curtis.

MMikaell says:

The Jewish people are a biological people based on our Y-DNA. I wrote a book in 2010 on this very subject. SEED COVENANT: Abraham’s SEED, DNA and Patrilineal Descent ISBN # 978-0-557-78623-7. (Lulu Publishing). The book is about how the ancient religion of Israel based on the Temple was always by “patrilineal” descent according to the father only, regarding who was of Israel or one’s tribe. It was only after the destruction of the Temple, and what had been a secular Jewish, non-priestly synagogue system developed by rabbis was the non-biblical idea of  “matrilineal” descent introduced.  It was my Y-DNA analysis and reports by people like Dr. Ostrer which convinced me that such a book was needed.  

Howard Metzenberg says:

Our reaction as Jews to Harry Ostrer’s book should be, “So what! We already knew that! Who cares?” 

This book contains nothing at all that is news. It has been possible for more than a decade to say that major Jewish ethnic communities (Ashkenazi, Yemmenite, and so forth) share distinct genetic markers and likely origins in the Middle East. For more than a decade, such genetic studies have been coming forth about the origins of both Jewish ethnic communities and the priestly groups (Cohanim, Levites). 

Although these studies generally support the claim that Jewish communities have ancient roots in the Middle East, none of them confirm literally the stories of origin from Jewish texts. For example, they clearly show that the Jewish people is not descended from a single male lineage (Abraham, Isaac, and Jacob). And while a high percentage of Cohanim (about 50%) do come from one genetic clade, others come from different and distinct lineages that have a common origin in historical time. Thus, it is impossible that all Cohanim are descendants of Aaron. 

What the public reaction to this book is missing is (1) a counterfactual hypothesis and (2) a control group for comparison. If Ashkenazi Jews are in fact on average 4th to 5th cousins, then using population geneticist Sewall Wright’s coefficient of relatedness, they share a common origin for between 1/512 and 1/2048 of their autosomal genes (those not inherited through the X-Y sex chromosomes). In actuality, in any two homo sapiens chosen at random from the entire human population are identical to every other human at well over 99.9% of genetic loci. 

Similar genetic studies have identified other ethnic and religious minorities that are descended from small founder populations (for example, the Finns, the Japanese, and the Druze). Other founder populations also have distinct genetic markers and genetic diseases that reflect their founding populations many centuries ago. 

If we were to choose a group of ethnic Jews and compare them to a random group of the same size from the general population, or from another distinct ethnic group that has isolated for geographic, linguistic, or religious reasons (Finns, Japanese, Druze) we would get the same result, which is that most human genetic variation is between individuals and only a small portion can be accounted for by they fact that they have been chosen from distinct ethnic groups. 

The genetic markers that link Jews and Jewish ethnic groups are a tiny portion of our genome, and contain only a small proportion of our genetic load. We share the vast majority of our humane genome with every other individual group and ethnic community on Earth. 

Recent discoveries in genetics demonstrate that our phenotype is not determined by our genes; rather, it is the expression of our genes in our environment. As Jews we are biologically as much like other human beings as we are like each other as Jews. We share with other human beings the entire panoply of behaviors found in Shakespeare’s plays: envy, jealousy, rage, passion, love, fear, righteousness. 

What is remarkable about the Jewish people is not that we share a few genetic markers, but rather that we share a tradition of studying the same texts and following the same mitzvot for thousands of years. This tradition is so strong that we have preserved several ancient languages. By following these traditions we have distinguished ourselves as a people throughout the world. And our own tradition tells us to welcome strangers who want to join us! 

Chag Sameach!

So the  mental  bipolar illness, for what I studied, written by eminent Professors and Reserchers, seems to be more common among people of Scandinavian ancestry , northen Germany near Denmark ancestry,, Irish ancestry and among people of Jewish ancestry. May be more genes are involved, some say a gene on the X-chromosome is involved;  there is a delation on the non-coding genes that control the production of the enzymes tyrosine-hydroxylases and tryptophane-hydroxylases.
 I also noticed by mere chance, that the tri-methyl-psoralen, used for the cure of the Psoryasis,
helped a little to ameliorate the humor and the sexuality probably acting on the tyrosinase produced in the nucleus caeruleus and substantia nigra of the hypotalamus, so the Psoralene could also help a little in the early stages of Parkinson disease. But those last are only my suppositions.  
I hope that better drugs can be found  by Sciencistst, that can  activate the genes involved in the bipolar illness.

jbob187a says:

Dr. Paul S. Appelbaum, the Dollard
Professor of Psychiatry, Medicine & Law at Columbia, and author and
historian Diana Muir Appelbaum strongly dispute Ostrer’s “discovery” of
a biological basis for “Jewishness” in the latest issue of GeneWatch


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A Case for Genetic Jewishness

In the book Legacy, geneticist Harry Ostrer argues that Jewishness is biological, not just cultural