18 March 2009

Genetics: Breast cancer study - not only Ashkenazi

A New York University study investigating the genetic roots of breast cancer is detailed here, focusing only on Ashkenazi women and ignoring other populations who carry these genes, such as Hispanic women who descend from Converso ancestors who settled the US Southwest.

Despite the fact that some Hispanic women - found to be descendants of Converso families (those forced by the Inquisition to convert to Catholicism in Spain and Portugal) who were early settlers in Colorado, New Mexico and other Southwest states - present with the same gene, and also despite the DNA genetic evidence that a growing number of Ashkenazi families actually have Sephardic roots, I fail to understand why more Sephardic and Hispanic women are not included in these studies.

In fact, the Jewish history of Italy and Sicily might also provide new food for thought in this area.

According to a Smithsonian Magazine article on the San Luis Valley women:
By comparing DNA samples from Jews around the world, scientists have pieced together the origins of the 185delAG mutation. It is ancient. More than 2,000 years ago, among the Hebrew tribes of Palestine, someone's DNA dropped the AG letters at the 185 site. The glitch spread and multiplied in succeeding generations, even as Jews migrated from Palestine to Europe. Ethnic groups tend to have their own distinctive genetic disorders, such as harmful variations of the BRCA1 gene, but because Jews throughout history have often married within their religion, the 185delAG mutation gained a strong foothold in that population. Today, roughly one in 100 Jews carries the harmful form of the gene variant.
The 2001 Colorado cases in San Luis Valley showed that these genes are present in Sephardic populations and are not limited to Ashkenazi women.

New York University is asking only Ashkenazi (Eastern European) women to participate in this nationwide project and to provide a DNA sample. Scientists hope to find genetic mutations that cause women in that population to develop breast and ovarian cancer at a much higher rate than others.
The workshop, "Beyond BRCA1 and BRCA2: The Next Generation of Genetic Discovery" will be offered at other places in the region as researchers attempt to enroll 1,000 women in the study. Women who attend the talk given by the Jewish Women's Breast and Ovarian Cancer Genetics Study at NYU, will also have the opportunity to give a DNA sample.
In the newspaper story, genetic counselor Lauren Carpiniello, who helps run the study, said that the scientists are focusing on women of European Jewish ancestry because they are much more likely than other groups to carry two genetic mutations linked to breast and ovarian cancer, known as BRCA1 and BRCA2, than other populations.

For more information, read the newspaper story, the Smithsonian Magazine link and Tracing the Tribe's previous post.

3 comments:

  1. Anonymous12:23 PM

    Because of the Smithsonian article I've been wondering is there any data regarding prevalence of BRCA mutations in Spain? After all many Jews converted and stayed in Spain.

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  2. That's an excellent question. I will ask some medical friends in Spain for information on that data, if it exists. It should be very interesting in light of what we know about Jewish history in Spain.

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  3. Jessica8:40 PM

    Also, if the gene goes back 2000 years, why not test Palestinians too?

    And absolutely the Sicilians and southern Italians. Even today, they still carry names that indicate probable Jewish origins--Tedesco, Spagna, Ben...,Rubini,

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