In a study published in the journal Science 24 October 2003, the New York Breast Cancer Study Group (New York Group for the study of breast cancer) not only confirms that every woman carries a mutation in the genes BRCA1 and BRCA2 is at a high risk of breast cancer but, against what had been held so far of this risk involving women from families with low breast cancer or those who have inherited the mutant gene from his father.

For this reason is very important that women try to get as much information as possible about whether there had been breast cancers in young women not only in the maternal family, but his father’s family (which can inherit a BRCA gene mutation).

In practice only under investigation are those women who develop breast cancer at an early age or relatives who developed breast cancer or ovarian cancer when they were young.

The women included in the study were Jewish “Ashkenazi”, an ethnic group that includes 90% of the six million Jews living in the U.S. The researchers chose this population because mutations that occur more often in this group have been identified, making genetic testing have been more easily done. However, in view of the Dr. Mari-Claire King, Director of the study, the findings apply to all women with BRCA gene mutations.

The study shows that at the age of 80 years, a woman with a mutation in one of the two BRCA genes has endured a 82% risk of developing breast cancer, whereas in women without this mutation the average risk of developing breast cancer at age 80 is around 13%.

Broken down by decades of his life is a risk that a woman with BRCA1 or BRCA2 breast cancer development is as follows:

At the age of 40 years ——– 20%
At the age of 60 years ——– 55%
At the age of 80 years ——– 82%

Although similar numbers of risk had been already published in previous studies, those figures were merely estimates, while the results of the study published in Science are based on diagnoses of breast cancer and genetic determinations performed in 104 women carrying mutations in BRCA genes and more than 800 relatives of these women.