Baltimore Sun
July 9, 1998

CHROMOSOME TIES MODERN JEWS TO AARON
Priestly caste shares a genetic marker, researchers say

By John Rivera
Sun Staff

A team of scientists say they've used modern genetics to prove a biblical tradition -- that today's members of the Jewish priestly class who consider themselves descendants of the brother of Moses can indeed trace their origins back thousands of years.

The researchers from England and Israel say they found that members of the kohanim, who call themselves descendants of Aaron, the biblical high priest and brother of Moses, share a Y chromosome with similar genetic markers that distinguishes them from the general Jewish population.

The results of the study will be published today in the journal Nature.

The kohanim include most, but not all, Jews with the surname Cohen, as well as Kaplan, Katz, Kahn or Rappaport. They trace their lineage to the very origins of the Israelites.

"In the Book of Numbers, you have a division of the Israelite population in the desert, wandering in the Sinai wilderness," said Barry M. Gittlen, an archaeologist and professor at Baltimore Hebrew University. One of these tribes is the Levites, who are singled out for service to the sanctuary, which contained the Ark of the Covenant. Each Levite was given a specific role, and those roles had a hierarchy.

"At the pinnacle of the hierarchy are the Aaronites, the descendants of Aaron, the priest who offer sacrifice," Gittlen said. Their descendants are the kohanim.
But Gittlen was skeptical that the tradition could be "proven" through science.

"I remain extremely dubious that genetic links can be traced all the way down to today," he said. "However, my mind can be changed by facts. "The kohanim still retain privileges in User.Event 7 was not expected here! Orthodox synagogues, as well as some other congregations. They are the first to be called up to read from the Torah. They bless the rest of the community on holidays and preside over a ceremony for first-born males. They must adhere to strict laws prohibiting contact with the dead and are not allowed to marry divorcees, widows or converts.

David B. Goldstein, an American who teaches at the University of Oxford, in England, was one of the researchers.


Genetics and tradition

He said the team used genetics to test the biblical oral tradition that priest status has been passed from father to son in a unbroken line that begins with Aaron. And the best way to do that was to compare the Y chromosome, which is passed from father to son, of the kohanim with that of the general Jewish population to see if there was any difference, Goldstein said.

"If it's in fact true that father-to-son inheritance of priestly status has been fairly strictly adhered to, that would make the prediction that the Y chromosome carried by priests should be in some sense distinguishable from the general population of Y chromosomes," Goldstein said.

The study of 306 Jewish men from Israel, Canada and England did find that the 106 self-identified kohanim for the most part shared a Y chromosome with unique genetic markers, while members of the general Jewish population had a multiplicity of types of Y chromosomes. It built on the results of a study released last year that first established kohanim passed on a similar Y chromosome.

Average: 3,000 years

Equally important, Goldstein said, was that researchers in the latest study found that while kohanim had a dominant type of Y chromosome, there wa some variation. If they were all identical, that would indicate th genetic link was very recent. Researchers, using statistical methods that they admitted could mot be precise, were able to estimate that the kohani line began no later than 700 years ago and could stretch as far back as 10,000 years. The average came out to about 3,000 years, a period which could date to the Exodus from Egypt.

The findings show "that oral tradition is actually right. That it has been followed over some period of time," Goldstein said. "This line of priestly Y chromosomes did not get started very recently. We can say that with statistical confidence."

For Morris Cohen, a retired court reporter who attends Beth Jacob Congregation in Park Heights, the study just confirms what he knows to be true.

"I think it would prove the Jewish theory that parents who hand down their lineage would be a true one," he said. "I think it will prove right dow the line that tradition that's gone from parent to parent to parent, that we are true kohanim."