Genetic Variant May Reduce Risk of Breast Cancer in Latina Women

         There has been a genetic variant found in many Latina women that has the ability to significantly reduce the risk of breast cancer. This variant is especially common in Hispanic women with indigenous American ancestry.

        The function of the gene is not completely clear to researchers, but they have found that the genetic variant can be the reason for less dense breast tissue in indigenous Hispanic women. It is already known that Hispanics in the United States have a less that 10% risk of developing breast cancer, while non-hispanics have about a 13% chance (New York Times). While other factors are already known to reduce the risk of breast cancer in Hispanics, this genetic variant is suspected to play an important role in the reduced risk of breast cancer.

 
        In order to determine if this genetic variant really played a role in risk reduction, Dr. Ziv (a professor of medicine and UC San Franciso) and his colleagues scanned and compared the DNA of breast cancer patients (3,000 samples) with the DNA of control subjects (8,200) from various populations. Dr. Ziv and his colleagues paid special attention to chromosome 6 and found a single nucleotide polymorphism (SNP) that was a protective variant. This variant was very frequent in Hispanic woman that were indigenous to Mexico (15% frequency), Columbia (10%) and Puerto Rico (5%). However, this protective variant was less than 1% frequent among white and African American populations in the United States. It was determined that women who carried one copy of the genetic variant were about 40% less likely to develop breast cancer and if two copies were carried, the risk is reduced by about 80%. The risk was significantly lower when concerned with an estrogen-receptor-negative form of breast cancer, since the genetic variant is believed to lower the amount of estrogen receptors in breast tissue.

       While the researchers are extremely supportive of their research, they warn against those who have the protective variant assuming that they will not get breast cancer. There are other factors that need to be considered such as outside influences and the possibility of other genes that can cancel out the protective variant.

Original Article: Genetic Variant May Shield Latinas From Breast Cancer