Jewish Ancestry and Cancer Risk

Review of Cancer and Genetics

Genes are pieces of information that are present in most of our body’s cells and are instructions for how the cell works. A pathogenic variant (mutation) is a change in a gene that causes it to stop working properly. If a person is born with a mutation in a gene that typically helps to prevent the formation of cancer, this can increase the chance for cancer to develop.

Mutations in genes can be passed down in families through the generations and increase the chance for cancer to develop in people that inherit these mutations. This is called “hereditary cancer”. There is a 50 percent chance that a person with a mutation will pass it to each of their children.

Hereditary Cancer Risk

Some groups of people share variants in genes that have been passed on through families for generations.  These are called “founder” mutations. For example, there are three founder mutations in the BRCA1 and BRCA2 genes in people with Ashkenazi (eastern European) Jewish ancestry. One in 40 people of Ashkenazi Jewish ancestry has of one of these BRCA gene founder mutations compared to 1 in 400 people of non-Ashkenazi Jewish background who may have any BRCA mutation. 

The BRCA1 and BRCA2 genes account for the majority of hereditary breast and ovarian cancer (HBOC). A  person who has a BRCA1 or BRCA2 mutation has “Hereditary Breast and Ovarian Cancer” syndrome with an increased risk for breast, ovarian, prostate, male breast, pancreatic, skin (melanoma) and possibly other cancers.

Genetic Counseling and Testing for Hereditary Cancer Risk

Genetic testing for hereditary cancer risk looks at the structure and “spelling” of the DNA in genes associated with cancer risk.

There are three possible results of testing:

  • Positive - A specific change (mutation) was detected that is known or highly likely to increase the risk of developing certain cancers.
  • Negative - A change was not detected.
  • Variant of Uncertain Significance (VUS) - A change was detected but there is not enough information at this time to determine whether this change increases cancer risk. 

Genetic counseling is recommended before moving ahead with genetic testing for hereditary cancer risk so a person can make an informed decision.

During the initial genetic counseling visit, you can expect to discuss:

  • Personal medical history including cancer history
  • Family history of cancer (if known)
  • Past genetic test results (if applicable)
  • An in-depth conversation of the benefits, risks, and limitations of testing 

If you decide to proceed with testing:

  • A sample (usually blood or saliva) is collected.
  • The sample is sent to a genetic testing laboratory and the results are returned to the genetic counseling team for review and discussion with the patient.
  • Please note that health insurance companies may cover most, if not all, of the cost of genetic testing. Coverage is determined on a case-by-case basis.

What happens when results become available?

Results may help guide cancer screening recommendations, options to lower risk for cancer, and treatment for any cancers that are diagnosed. They may also provide information for other family members. 

Where can I go for more information?

Anyone who is concerned about the possibility of hereditary cancer is encouraged to discuss their personal and/or family history of cancer with their health care provider. 

To schedule an appointment in the William G. Rohrer Cancer Genetics Program of MD Anderson Cancer Center at Cooper, call 855.MDA.COOPER (855.632.2667). 

This educational material was supported through a generous grant from the Jewish Women’s Foundation – a committee of the Jewish Federation of South Jersey.