A family tree should go back three generations.
(JOSE LUIS PELAEZ/BLEND/GETTY IMAGES)
"I draw out a family tree for three generations," says M. William Audeh, MD, a medical oncologist who works in cancer risk assessment at Cedars-Sinai Medical Center in Los Angeles. And that means both branches: "Many women assume they should only be concerned about their mother's side of the family, but breast cancer risk can be inherited from either parent," says Dr. Audeh.
The breast cancer gene
Whatever you learn from your own family tree, you may decide to be tested for the BRCA-1 or BRCA-2 gene mutations. Far from every woman who gets breast cancer carries BRCA gene mutations, but those who do have one of the mutations (they’re more common to women of Ashkenazi Jewish descent, for instance, and a recent study suggested that U.S. Hispanic women are also at higher than normal risk) are three to seven times more likely to get the disease than women without alterations in those genes.
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More about genes
Even testing negative for the BRCA mutations may not provide the kind of closure you were looking for. Women with a family history of breast cancer will still need to be extra vigilant.
