Family history matters, especially for your future cancer risk
January 20, 2021
This time of year, personal health is at the forefront of our minds. Generally, people tend to make resolutions about diet and exercise, but an important factor often gets overlooked in our "new year, new you" planning: gathering information about your family history.
Knowing specifics about your family’s health history can change the trajectory of your future. We know that many traits are inherited. These genetic markers are handed down through our DNA. Also inherited are genetic mutations – altered DNA segments that can predispose families to increased risk of conditions such as heart disease, sickle cell anemia, or breast, ovarian, and colon cancer.
Approximately half of all people in the U.S. have at least one heart disease risk factor, as well as modifiable cancer risk factors such as obesity and inflammation. The most common form of inherited cardiovascular disease is familial hypercholesterolemia (FH) which increases cholesterol levels. FH is estimated to affect 1 in 200 to 1 in 250 individuals.
However, 5% to 10% of cancers are associated with inherited genetic mutations. So, just because a close family member had a certain health condition does not mean that will also be your destiny.
By collecting your family's health history – and pairing it with personalized genetic counseling and genetic testing – you can learn which cancers truly run in the family, and which may be avoided with earlier or increased colonoscopy, mammography, or other screenings, as well as lifestyle modifications such as diet, exercise, or preventive medication.
The new year is a good time to connect with loved ones by phone or Zoom and start having those conversations. Start by gathering the basics of your family's health, and that will help you get better context into your personal risks for certain cancers.
UT Southwestern's genetic counseling team in the Simmons Comprehensive Cancer Center also meets with patients to address a range of hereditary cancer-related needs, from strategies to mitigate known cancer risks to allaying fears raised by direct-to-consumer tests such as 23AndMe. Your family health history, paired with data analysis from our proprietary CancerGene Connect tool, can zero in on risk areas and any necessary prevention strategies.
We've compiled a list of ways to get started and ask the important questions about your family’s medical history.
First thing's first: Get buy-in
Having personal conversations about health history can be a delicate matter. Some relatives may not want to recount painful memories or discuss their health due to cultural traditions. Conversely, some relatives may share more that you ever cared to know!
Don't pressure anyone; set a positive and transparent tone and you’ll be more likely to get a positive response. At the beginning of your research, put together a short list of reasons why the project is important to you. You might also offer to share your findings with family members when you're done, since you all could benefit.
Create a family tree
1. List your known relatives
Start with your immediate family: your siblings, children, and parents. Then, branch out to aunts and uncles, nieces and nephews, first cousins, and grandparents. If you know the next generation (great aunts, second cousins, etc.), include them, too. You can find family tree templates or printable genealogy forms online.
For each relative, record their date of birth, date and cause of death, which side of your family they are from (paternal or maternal), country of origin, and ethnicity. If you're unsure, write down your best guess and verify the information when you can. Resources such as baby books, a family Bible or other religious tome, and existing family trees from genealogy enthusiasts can be a great starting point.
Feeling stuck? Reach out to an older relative to help fill in the gaps.
2. Create a checklist of medical questions
Consider making a paper or electronic form that includes general health questions for family members on your list. It should include their personal history of conditions such as:
- Alzheimer's disease or dementia
- Birth defects (such as spina bifida, cystic fibrosis, or Down syndrome)
- Cancer (which primary sites/types and stages, if possible)
- Cognitive disability
- Hearing loss
- Heart disease
- High blood pressure
- Kidney disease
- Mental illness
- Substance use (alcohol, tobacco, controlled substances)
- Vision loss
Include other conditions you may be concerned about, such as gynecologic, liver, or pancreatic diseases. Record the relative's age when they were diagnosed, as well as treatments used and their outcomes. You'll also want to ask about lifestyle, such as tobacco use, diet, and exercise habits.
Related reading: Do I Need Genetic Testing for Breast Cancer?
Considerations for estranged or adopted patients
We recognize that sometimes genetic information can be tough, if not impossible, to come by. In these cases, you might start with the adoption agency office or a public information office, such as the county clerk or recorder's offices. These entities may have records of dates of birth, death, and marriage certificates that help you track down and piece together parts of your family history.
3. Reach out to relatives
Your older relatives might be able to provide a foundation of long-term family history trends. Verify your data against medical records, if possible. Sometimes diseases that appear to "run in the family" are not inherited but are actually attributed to environment, lifestyle, or diet. Though medical records are sometimes tough to obtain, the documents can give you accurate and well-rounded information.
Once your research is complete, keep your family history in a safe place and update it every few years with births, deaths, and diagnoses.
If you have concerns about your family history, a genetic counselor can help you determine what conditions in your family’s history can truly be traced to genetics, what is modifiable, and how to reduce your risks of certain conditions, including cancer.
Related reading: Genetic testing for prostate cancer
Preparing for genetic testing and counseling
Before meeting with a UT Southwestern cancer genetic counselor, we'll ask you to complete an electronic questionnaire called CancerGene Connect, which essentially translates your family history document into our risk-ratio algorithm.
Using this tool – along with a blood or saliva sample you provide – we can identify inherited genetic mutations and adjust your potential risk for cancers, such as BRCA1 and BRCA2 mutations associated with breast, ovarian, pancreatic, and prostate cancers, or MLH1, MSH2, MSH6, and PMS2 mutations associated with Lynch syndrome which primarily increases lifetime colorectal and endometrial/uterine cancer risks.
Gathering your family history and populating CancerGene Connect prior to your appointment allows your genetic counselor to focus on your results, concerns, and potential next steps during your visit. Watch this video to learn more.
Based on your results, the genetic counselor can help you plan appropriate next steps. Your plan may include connecting with a cancer prevention expert. We can also help you schedule earlier or more frequent mammograms, colonoscopies, or other health screenings.
Your counselor or healthcare provider may also suggest that other family members receive genetic testing or see their doctors for advanced screenings, depending on your family's specific risks.
Reminder about direct-to-consumer testing
Genetic counseling with clinical testing is not the same as direct-to-consumer genetic testing:
- Genetic counseling is an expert review of your genetics to determine your risk for certain conditions, such as cancer, and determine appropriate testing. This can involve a blood or saliva test and an appointment with an expert to discuss your results and next steps.
- Direct-to-consumer tests are commonly designed to answer some popular genetic questions about your ancestry, customized exercise routines, or even which wine you may prefer. These tests can sometimes pick up on clinically relevant genetic changes specific to certain ethnicities. At-home tests involve mailing a cheek swab or saliva sample collection kit to a consumer lab. The lab may send your results with varying availability of expert support.
The results from direct-to-consumer tests are not structured to clinically support your health goals, but they do have the potential to create and uncover family drama. Connections made through the organization's database may reveal previously unknown half siblings or that a parent isn't biologically related to their child. When you work with a genetic counselor, we can help you navigate your results, including next steps in the health system.
Read the fine print. With many direct-to-consumer testing options, data gleaned from your cheek or saliva sample becomes property of the company to which you send it. Unfortunately, many consumer sites may include verbiage to automatically waive privacy rights when you order the test kit. In other words, they can sell or share your genetic and health data however they choose.
Genetic testing information at UT Southwestern is protected by HIPAA privacy laws. In the United States, patients are also protected from genetic discrimination through a series of laws called the Genetic Information Nondiscrimination Act of 2008.
Under these laws, a positive test for a genetic condition is not considered a pre-existing condition. The goal is to protect individuals from discrimination in forms such as denying employment, medical insurance coverage, or increasing premiums.
Family history matters
If you find out that you have a genetic risk factor, that does not mean you or your family members will definitely get that condition. Remember that just 10% of cancers are inherited. That means that the risks for more than 90% of cancers may be modifiable by adjusting diet, exercise, or other variables in any person’s lifestyle.
The more people in your family who know about genetic risks, the more people can benefit from additional screenings, earlier screenings, or simply peace of mind that their risk is less than expected.