For years it has been conventional wisdom that Ashkenazi women alone have an increased risk for certain forms of breast cancer. But a new study is challenging that claim of genetic researchers.
The study, published in this month’s issue of The American Journal of Public Health, found that although three recognized breast cancer mutations are present in 2 to 3 percent of Ashkenazi Jewish women, the mutations are not unique to Ashkenazi Jewish women.
Sheila Rothman, one of five Columbia University College of Physicians & Surgeons researchers who conducted the study, said other studies have found that the same mutations are "widely distributed in some other populations … that don’t identify as Ashkenazi Jews."
Rothman stressed that the prevalence of these genetic mutations in Ashkenazi Jewish women "is not something you want to dismiss, and it is important that women go for testing and understand their risk." But she noted that a large study of Spanish women who had breast cancer found that one of the three mutations accounted for 16.7 percent of all mutations.
Rothman and the other researchers also found that a study of Moroccan Jewish women "selected without regard to family history of cancer" revealed a 1.1 percent incidence of one of the three mutations: "approximately equal to that in Ashkenazi Jews."
"Researchers have also discovered the [mutation] in numerous women who do not identify as Jewish or appear to have Jewish ancestry," the study said. It cited studies in which one of the mutations constituted 10.1 percent of all the mutations on the BRCA1 gene in Dutch women, 6.5 percent of mutations in German women, and 3.4 percent of mutations in Czech women. In the United States, this mutation was identified as the most common BRCA1 mutation in the sample of Hispanic women in Los Angeles. It has also been found in Hispanic women in Colorado, in Spanish Gypsies and among South Indian women.
"Overall prevalence data remain unknown because population-based studies have not been conducted in these groups," the study said.
Elana Silber, director of operations for Sharsheret, a national not-for-profit organization that supports young Jewish women facing breast cancer, said this study does nothing to "minimize the interest or concern in the Jewish community" about breast cancer.
"Regardless of whether other groups of women have it," she said, "this is one of the hottest topics for Jewish women who have breast cancer in their family. … People should know that genetic counseling and testing can help determine if a woman carries an altered gene that increases her risk for developing breast or ovarian cancer."
Asked about the importance of the Columbia study, Silber said: "The good thing is that they are still doing research, and the more information we have the better the chance of screening for it and catching it early. If detected in its early stages, breast cancer can be cured."