Genes set Jews apart, study findsGlad to see a news report finally implying what I've been saying since the late 1990s: a racial group is aÂ partly inbred extended family.
Those of European descent are more closely related with one another than with their fellow countrymen, say researchers who were primarily studying genetic diseases.
By Thomas H. Maugh II, Los Angeles Times
Jews of European descent living on opposite sides of the globe are more closely related to one another than they are to their fellow countrymen, according to the largest study ever conducted of what it means genetically to be Jewish. Ashkenazis, the primary group descended from European Jews, are all as closely related as fourth or fifth cousins would be, the study found.
Frank Salter may have invented this way of thinking about racial relatedness in terms of cousins back in the 1990s. It's very useful, but it has to be understood, not surprisingly, relativistically.
"Jews really are different from their non-Jewish neighbors," said Dr. Harry Ostrer, a geneticist at the New York University Langone Medical Center, coauthor of the study appearing Thursday in the American Journal of Human Genetics.Does anybody actually know what are unarguable criteria for defining a "separate race" from a "distinct population?" It seems to me that biologists have a hard enough time deciding whether dogs, wolves, and coyotes are separate species or not to pronounce authoritatively on the differences between separate races and distinct populations. It would be simpler and clearer to adopt my terminology: Jews are a partly inbred extended family.
They are not different enough to be considered a separate race, as some experts have argued, he added, but definitely are a "distinct population" – the result, presumably, of cultural separation down through thousands of years.
The study, which was conducted primarily to further medical knowledge of genetic diseases, rejected a highly controversial idea that Ashkenazi Jews are descended from Khazars in Eastern Europe who converted to Judaism – an idea that has recently been used in an attempt to discredit the idea that Jews belong in Israel because it is their historic homeland.So, this study leaves out individuals who are only part-Jewish. It would be interesting to know what percentage of today's self-identified Jews have fewer than four self-identified Jewish grandparents. Conversely, what percentage of Americans who don't identify as Jews had at least one Jewish grandparent?
The study shows that there is "clearly a shared genetic common ancestry among geographically diverse populations consistent with oral tradition and culture …and that traces back to the Middle East," said geneticist Sarah A. Tishkoff of the University of Pennsylvania, who was not involved in the study. "Jews have assimilated to some extent, but they clearly retain their common ancestry." ...
Although the study sheds light on Jewish history – providing new information about the separation between North African and European Jews 2,500 years ago and the near extinction of European Jews in the Middle Ages – its major goal is to identify genes for many diseases that are more common in Jewish groups, such as breast cancer, Gaucher's disease and Tay-Sachs.
The higher incidence of those diseases among "Abraham's children" will allow scientists to more readily find genes that causes the illnesses and then extend that knowledge to the general population, said geneticist Gil Atzmon of Yeshiva University's Albert Einstein College of Medicine in New York, coauthor of the paper.
The study examined 237 Jewish individuals from seven regions of the world, comparing them with 418 non-Jewish people from the same regions. Each of the Jewish subjects had all four grandparents from the same population.
The researchers studied about 160,000 sites across the entire genome, providing a great deal more information about the population than has ever been available. ...The theory is that the hothouse Babylonian Captivity of intellectuals led to the emergence of Hebrews as a self-aware nation.
The Jewish people, according to archaeologists, originated in Babylon and Persia between the 4th and 6th centuries BC.
The modern-day Jews most closely related to that original population are those in Iran, Iraq and Syria, whose closest non-Jewish relatives are the Druze, Bedouins and Palestinians, the study found.It could well be that, on average, today's Arab-speaking Palestinians are more closely related to the Jewish inhabitants of Palestine in, say, 1 AD than are the current Jewish inhabitants of Israel. (In James Michener's novel about an archaeological dig in Israel,Â The Source, one character is a sardonic Palestinian archaeologist who points out that his ancestors have, so far as anybody can tell, been living in the same grove of olive trees since Biblical times.) But, politically, so what? To my mind, possession is nine-tenths of the law.
Sometime in that period, the Middle Eastern and European Jews diverged and the European branch began actively proselytizing for converts.The Jewish population in Europe grew so much that a lot of Jews in early modern times had to move down the economic ladder into lousier jobs. The constant kvetching about being poor in, say,Â Fiddler on the Roof, is inspired in part by the characters' knowledge that their ancestors hadn't been as poor — an awareness largely lost on today's Jews.
At the height of the Roman Empire, about 10% of the empire's population was Jewish, although the bulk of them were converts. Some Khazars were also incorporated during this period.
"That explains why so many European and Syrian Jews have blue eyes and blond hair," Ostrer says. It also explains another of the team's findings – that the population most closely related genetically to European Jews are Italians.
The data also show what the researchers call a "bottleneck" in the Jewish population during the Middle Ages. The population of European Jews shrunk below 50,000 during that period because of disease, prejudice, anti-Semitic edicts and the Crusades, Atzmon said.
Afterward, however, an easing of restrictions led to what is known as the "demographic miracle," in which the Jewish population rose twice as fast as that of other Europeans, reaching more than 5 million by the 19th century.