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Scientific discovery shows genetic link to biblical Aaron

NEW YORK, Jan. 13 (JTA) — A scientific discovery of what could be called the “Kohen chromosome” has sparked interest among Jewish religious leaders of all persuasions and could have religious implications that the scientists themselves never anticipated. After about four years of work, Dr. Michael Hammer, a geneticist who works at the University of Arizona at Tucson, and Dr. Karl Skorecki, a professor affiliated with Haifa’s Rambam Medical Center and the Technion-Israel Institute of Technology, found that Jewish priestly lineage could be genetically traced back to the progenitor of all Kohanim, the biblical Aaron. In a sample of 188 men, they found that the lineage is visible in two markers on the Y chromosome that is transmitted from father to son. Hammer warned in a telephone interview, however, that the research is not complete and that only 20 percent of the men who might be descendants of Aaron had those particular markers. The findings have prompted questions whether genetic testing could be used as the basis for Jewish legal decision-making. Skorecki said, “This research is not currently applicable to testing of individuals with regard to their status in the Jewish priesthood.” “Persons should be valued on their own individual merits, without regard to their ancestry,” he wrote in an electronically mailed response to questions from a reporter. But after the findings were published in the London-based scientific journal Nature and were picked up in The Jerusalem Post, Skorecki received many requests from Orthodox Jews in Israel who want to be tested to prove scientifically that they are descendants of Aaron. In the time of Israel’s First and Second temples, the Kohanim performed holy rites at the site where God was believed to be made manifest. Jews were traditionally divided into three classes: Kohanim, Levites and Israelites. Since the destruction of the Second Temple, in 70 C.E., the priests’ role has changed. The honor of the first blessing over the Torah is given to a Kohen in Orthodox and some Conservative congregations. Kohanim also recite special blessings during worship on some Jewish holidays. The ritual, called duchening, is a mystical and spiritually powerful act in which a Kohen takes off his shoes, has his feet washed and then, standing before the congregation, raises his tallit over his head and with outstretched arms acts as a conduit for God’s blessing over the congregation. “It’s one of those things that is numinous,” said Rabbi David Wolpe, who teaches Jewish philosophy at the Conservative movement’s Jewish Theological Seminary. “It gives you a sort of awe-struck sense of something beyond us.” The ritual is being reclaimed by some liberal Jews who did away with it in the move toward egalitarianism in years past. But in the last two or three years, the Conservative movement has officially begun to encourage its practice. The Reconstructionist movement’s founder, Rabbi Mordecai Kaplan, discarded all references in prayer to the Jews as God’s chosen people, and his followers are not likely to reintroduce a custom that represents “the chosen of the chosen,” said Rabbi Michael Cohen. Cohen is a Reconstructionist rabbi who in another denomination would be considered a Kohen. Reconstructionists “don’t deny that Kohanim existed at a certain point in time, but we understand now that the notion of someone having a right purely by birth doesn’t sit well with many of the principles that we hold dear,” he said in a telephone interview. For those who observe the Orthodox interpretation of Jewish law, Kohanim are bound by certain restrictions. They are not permitted to marry divorced women, to go near corpses or into cemeteries. Some rabbis have expressed concern that the genetic testing could be used to define who is a Kohen when the man in question may not care. In Israel, for example where the Orthodox rabbinate controls marriage, a secular man who is also a Kohen could potentially be prohibited from marrying a divorced woman. Most rabbis of all denominations, though, dismissed that as highly unlikely. While not inconceivable, “that is a far-out possibility,” said Orthodox Rabbi Irving Greenberg, who is himself a Kohen. “Though with the Israeli rabbinate, you never know.” Rabbi Avi Shafran, a spokesman for Agudath Israel of America, which represents fervently Orthodox interests, said he “severely doubts” whether genetic testing could ever be used to make a Jewish legal, or halachic, determination of whether a man is a Kohen. Jewish law permits as evidence only those “things that are discernible to the five unaided senses,” Shafran said. “If it’s too small to be seen by the unaided eye,” then it could not be used in making a halachic determination. Of the men who want to be tested for the markers, “I think it’s more a matter of their curiosity than for any down-to-earth purpose,” Shafran said. “No one will ever be forced to take the test.” Rabbi Ammiel Hirsch, executive director of the Association of Reform Zionists in America, said he did not expect that the Israeli Orthodox rabbinate would soon, if ever, be able to use the findings in any way that would hurt non-Orthodox Jews. “I don’t really understand why people would be overly concerned. One small study wouldn’t do it” to establish these findings as widely accepted fact, he said. Hammer, an unaffiliated Jew whose most recent religious connection has been to the Indian guru Sri Chinmoy, said he was motivated to locate the Kohen chromosome by historical and scientific impulses rather than piety. As a result of the unanticipated potential religious implications, the scientists are uncertain how far to take their research. “We’re in a dilemma,” Hammer said. “We can’t prove or disprove very easily if someone is a Kohen from this data. Do we want to?” “If we don’t, will somebody else come along, a genetic-testing company, and do it, or would the Orthodox rabbinate hire some company to do it for them?” he said. “Are we in a situation where someone could patent this as a genetic test?” “This is very troublesome and worrisome,” he said. “It’s up to the scientists to say what can and cannot be determined at this point,” but “the ethical issues are up to the rabbinate, or whoever’s in charge of those rules and laws and things.”