Study: Gene Mutation Boosts Colon Cancer Risk for Some Jews

A common genetic mutation found in Jews of Eastern European descent appears to double or triple the risk of colon cancer, according to U.S. and Israeli researchers reporting in the journal Science.

The mutation in a gene called BLM is found in about 1 percent of Ashkenazi Jews, according to researchers. There are an estimated 10 million Ashkenazi Jews worldwide, with about 2.5 million in Israel and 1 million in the New York City area.

"When this mutation is inherited from both parents, it causes a serious disorder called Bloom syndrome, which greatly increases an individual's predisposition to cancer," said Dr. Stephen Gruber, director of clinical cancer genetics at the University of Michigan.

"Our data show that people who inherit the mutation from just one parent face a two to three times greater risk for colorectal cancer," Gruber said.

Two studies of the BLM gene -- one involving mice, the other involving humans--were published in Science.

In one study, researchers compared the DNA of 1,244 Ashkenazi Jews with colorectal cancer to 1,839 Ashkenazi Jews who did not have the disease, and found that 2 percent of those with cancer had the gene mutation compared to less than 1 percent of the healthy participants.

In the other study, researchers found that one mutant copy of the BLM gene was linked to an increased risk of cancer in mice.

Other Sources: Science