I'm fortunate to be part of an international consortium that studies data from 400,000 women in more than 35 countries on six continents. Thanks to these participants, we have been able to develop new tools to evaluate something called polygenic risk, which has been validated in more than a dozen prospective studies.
It should be noted that approximately one woman in 200 or 300 carries a mutation of a rare predisposition gene. So it's quite rare. We also studied the frequency of mutations in the BRCA1 and BRCA2 genes, which I was involved in discovering, in certain ethnic groups.
What we're proposing is the use of about 300 markers that are very frequent. By combining this signature with other risk factors, such as breast density, certain lifestyle patterns, and hormone factors, we could assess personal risk and stratify it into three groups.
For example, we followed 4,000 women in our study. Of these, 80% were at or near the same risk as the general population, 15% were at intermediate risk, meaning that they would have to start doing an annual mammogram at age 40, and 5% were at high risk. In their case, they should start doing an annual mammogram immediately, in addition to using magnetic resonance imaging, because there is indeed more than just mammograms. You know the statistics better than I do, but we know that 17% of all breast cancer diagnoses are made before the age of 50, so it's very important to take action.
Internationally, we are also working on risk prediction models or tools, such as genomic signatures, that are specific to various ethnic groups, such as Asians and Hispanics. It's very important.