We’ve known from earlier research that an increased risk of breast and ovarian cancers is linked to mutations in the BRCA-1 and BRCA-2 genes.

Now, a new U.S. study examining those genes may predict risks even more accurately.

Researchers studied more than 19,000 women with the BRCA-1 mutation and close to 12,000 women with the BRCA-2 mutation from 33 countries.

They discovered that different types of mutations led to different levels of risk in different organs.

For instance, one BRCA-2 mutation led to an increased risk of breast cancer, while another mutation of the same gene led to an increased risk of ovarian cancer.