October is Breast Cancer Awareness Month, and we want to share stories from customers like Kristy who’ve taken action after learning she carried a variant in the BRCA1 gene associated with a higher likelihood of developing breast and ovarian cancer.
Kristy never got to know her dad. He died when she was just two. Her mom, who was busy raising Kristy and her three brothers and three sisters, never shared a lot about him.
And then, in 2016, about 50 years after her father’s death, Kristy learned something surprising about her dad after using 23andMe.
“I found out I was half Jewish, specifically Ashkenazi Jewish,” she said. “It was fun to get my (23andMe) ancestry results and share them with my six siblings.”
Ashkenazi Ancestry
Raised in a busy midwest Catholic family, Kristy had no idea her dad was 100 percent Jewish. He had left the faith and became a Catholic when he married her mom. The news was interesting; it also reoriented some of what she knew about her family. But at the time, Kristy didn’t recognize the significance of that family history for her health, and the health of her brothers and sisters and their children.
“I knew that he was part Jewish, but nothing near 100 percent Jewish,” she said recently.
It wasn’t until two years later that she found out just how important knowing her ancestry was. Still, before explaining what happened, it helps to know a little about the uniqueness of Ashkenazi ancestry.
Ancestry and Health
The word “Ashkenazi” comes from Ashkenaz, a descendant of Noah in the Hebrew bible. People with Ashkenazi ancestry have roots in Jewish communities in Central and Eastern Europe, who had migrated there via Southern Europe. As with many groups, members married and raised families within their faith in these small, close-knit communities. Ashkenazi people were also were more isolated because of violent persecution directed against them from surrounding communities. Over centuries this isolation helped establish a distinct religious, linguistic, and cultural Jewish identity.
And similar to other culturally or geographically isolated populations, this isolation (and a resulting “founder bottleneck”) has created distinct genetic heritage over generations, which can also have implications for health.
So, for example, people with Ashkenazi ancestry are more likely to carry genetic variants that cause single-gene recessive inherited conditions. These include conditions such as Gaucher disease, Canavan disease, and Tay-Sachs disease. People of Ashkenazi ancestry also have a higher prevalence of genetic variants in the BRCA1 and BRCA2 genes associated with increased risk for breast, ovarian, prostate, and certain other cancers.
Kristy knew none of this.
A New Genetic Health Risk Report
Then in 2018, 23andMe released its BRCA1/BRCA2 (Selected Variants) Genetic Health Risk* Report, the first direct to consumer genetic test for inherited cancer authorized by the FDA. The report looks at three of the BRCA variants most common in people of Ashkenazi ancestry. Women with one of these variants have a 45-85 percent risk of developing breast cancer by age 70, compared to about 13 percent in the general population. In addition, having one of these variants increases the risk for ovarian cancer. After opting to receive the information and going through a tutorial about the report, Kristy opened up her results.
She had one of the variants in the BRCA1 gene.
“And so began an almost two-year journey of discovering what this all meant,” she said.
Kristy’s Health Journey
For Kristy, it meant consulting five different doctors and talking to a genetic counselor to best understand her risk. Initially, her doctor did a confirmatory test. She did indeed carry the variant. Then, working with her doctors, they looked at her family medical history. An aunt had died of ovarian cancer, and a grandmother had survived ovarian cancer. They used all this information to give their best estimate for her risks.
“I think I had a 50 percent risk for ovarian cancer and up to an 80 percent risk for breast cancer,” Kristy said.
Her aunt had died of ovarian cancer at 52, and Kristy, nearing that age herself, didn’t want to wait. She decided to have preventative surgeries, a double mastectomy, and an oophorectomy (removal of her ovaries). Later Kristy had reconstructive surgery. It was an emotional and at times frightening period. But what she hadn’t expected was how hard it was to talk to her family about it.
Not only did the knowledge about her own risk also have implications for her sisters, but also her brothers. Like Kristy, they all could have inherited the same risk variant. And it wasn’t just about her siblings but their children as well.
“My family, in particular my sisters, were having a tough time understanding why I was going through this, and then why they may have to go through it too,” she said.
Talking to Family
At first, they thought she might be overreacting. So because of that response, Kristy went back to her genetic counselor to once again review all the findings. She wanted to make sure she understood the risk, and reconfirm her decision.
“I went through all the numbers and the family health history and everything to make sure I was doing the right thing,” she said.
It took a while for them to grasp the importance of it all. But eventually, all of her sisters and two of her three brothers tested. All three of her sisters had the variant, as well as one of her brothers. Eventually, they were able to share information to help each other work through what to expect. For her siblings with children, it’s information they could share with them as well.
A Gift
But if it weren’t for Kristy’s 23andMe reports, they may have never known.
Indeed, many people who carry a BRCA genetic variant associated with an increased risk for breast, ovarian, prostate, and certain other cancers only find out that they have one of those variants after they’ve been diagnosed with cancer. They often don’t have a family history of cancer or don’t know their family medical history or ancestry. These are all used to evaluate whether a patient should get BRCA testing. A study by 23andMe researchers published last year in the journal Scientific Reports found that many of those individuals who carry one of the BRCA risk variants that 23andMe tests for are likely to be missed under current clinical testing criteria.
For Kristy, the knowledge gave her and her family potentially lifesaving information.
“I was given the gift of knowing,” she said. “Some people never get that chance.”
Learn more about the BRCA gene and its role in some cancers here.
*The 23andMe PGS test uses qualitative genotyping to detect select clinically relevant variants in the genomic DNA of adults from saliva for the purpose of reporting and interpreting genetic health risks and reporting carrier status. It is not intended to diagnose any disease. Your ethnicity may affect the relevance of each report and how your genetic health risk results are interpreted. Each genetic health risk report describes if a person has variants associated with a higher risk of developing a disease, but does not describe a person’s overall risk of developing the disease. The test is not intended to tell you anything about your current state of health, or to be used to make medical decisions, including whether or not you should take a medication, how much of a medication you should take, or determine any treatment. Our carrier status reports can be used to determine carrier status, but cannot determine if you have two copies of any genetic variant. These carrier reports are not intended to tell you anything about your risk for developing a disease in the future, the health of your fetus, or your newborn child’s risk of developing a particular disease later in life. For certain conditions, we provide a single report that includes information on both carrier status and genetic health risk. Warnings & Limitations: The 23andMe PGS Genetic Health Risk Report for BRCA1/BRCA2 (Selected Variants) is indicated for reporting of the 185delAG and 5382insC variants in the BRCA1 gene and the 6174delT variant in the BRCA2 gene. The report describes if a woman is at increased risk of developing breast and ovarian cancer, and if a man is at increased risk of developing breast cancer or may be at increased risk of developing prostate cancer. The three variants included in this report are most common in people of Ashkenazi Jewish descent and do not represent the majority of BRCA1/BRCA2 variants in the general population. This report does not include variants in other genes linked to hereditary cancers and the absence of variants included in this report does not rule out the presence of other genetic variants that may impact cancer risk. The PGS test is not a substitute for visits to a healthcare professional for recommended screenings or appropriate follow-up. Results should be confirmed in a clinical setting before taking any medical action. For important information and limitations regarding other genetic health risk reports and carrier status reports, [visit https://www.23andme.com/test-info/].
