|
|
May 19, 2000/14 Iyar 5760, Vol. 52, No.37
U of A researcher heads breakthrough genetic study
CHRIS GARIFO
Special to Jewish News
Genetically speaking, Jews aren't being assimilated to any significant degree, says a researcher at the University of Arizona.
Michael F. Hammer, an associate researcher in the Division of Biotechnology at the Arizona Research Labs, is the lead author of a new study, reported in the May 9 issue of the "Proceedings of the National Academy of Sciences," that suggests the Diaspora - the dispersion of Jews throughout the world - has not had a strong effect on the genetic link among Jewish men.
The study, conducted by an international team from the United States, Europe, South Africa and Israel, shows that Jews are closely related to their Arab neighbors.
"We saw such a strong signal of a Middle-Eastern origin, it was kind of surprising," Hammer says.
Hammer says other studies have been conducted on Jewish genetic links, but the results often have been contradictory, resulting in disputes over Jewish origins.
"Our work definitely refutes a lot of that discussion of alternate origins for Jewish populations," Hammer says. "It shows that we really are a single ethnic group coming from the Middle East. Even if you look like another European with blue eyes and light skin, your genes are telling that you're from the Middle East."
One of the study's goals was to determine just how much assimilation had occurred since the Diaspora, which took place during the sixth century C.E.
"People say Jews look like Europeans because clearly there's been hanky-panky through the generations," Hammer says. "But not that much, according to our study."
Hammer explains: "You might expect that, if there were a lot of Jewish women taking non-Jewish men as husbands, then their children would still be Jewish but their Y-chromosomes would be non-Jewish. But we didn't see that, which indicates that there's been isolation."
According to Halacha (Jewish religious law), a person's Jewishness is inherited from the mother. However, the Y-chromosome - the male chromosome - passes from father to son usually unchanged.
Hammer says that, because environmental changes can over time affect genes that control other features such as eye color, hair color and baldness, the Y-chromosome's stability makes it a more reliable marker than the classic genetic markers used in previous studies.
"(The Y-chromosome) has only got a couple of genes and they're most likely not going to be influenced by the environment," Hammer says. "Therefore, it may give us the strongest handle on the history of the (Jewish) population rather than on the history of the adaptation to a new climate."
Hammer says the study focused on the Jews of the Diaspora because they are "a great model for looking at more of a short-term disper- sal, something that happened within the last couple of thousand years, rather than the last 100,000 years."
The study focused on specific regions of the Y-chromosomes in 1,371 men from 29 populations around the world, according to New York University Medical Center and School of Medicine. The sampling included Jews and non-Jews from Europe, the Middle East and Africa.
Included in the study were Arab subjects from all five Middle-East groups: Druze, Lebanese, Syrians, Palestinians and Saudis. Hammer says the findings show that Jews' nearest cousins "are Arabs and we should be nice to each other."
Hammer, who has been a U of A researcher for nine years, plans to continue his work into the genetic origins of the Jews. He says one of his interests is in determining why Ashkenazic Jews have a high frequency of rare diseases.
Besides Hammer, the other authors of the study are Dr. Harry Ostrer of the New York University School of Medicine; Alan J. Redd, Elizabeth T. Wood, M. Roxane Bonner, Hamdi Jarjanazil and Tanya Karafet from U of A; Silvana Santachlara-Benerecetti, University of Pavia, Italy; Ariella Oppenheim, The Hebrew University of Jerusalem; Mark A. Jobling, University of Leicester, England; Trefor Jenkins, University of Witwatersrand, South Africa; and Batsheva Bonne-Tamar, Tel Aviv University, Israel.
Hammer says one reason he began the research was his curiosity about his own Jewish roots.
Hammer says he has only been "mildly observant" - he did not become a bar mitzvah - but he is becoming more observant because of his research and intends to raise his two children as Jews.
|
