Genetic testing is frequently advised for individuals suffering from specific health issues, including cardiovascular diseases, cancer, and autoimmune disorders. Whether it’s conducted at your doctor’s suggestion or on your own initiative, how you approach genetic testing is crucial.
Genetic counselors, like Carol Cremin, MSc, CCGC, a clinical assistant professor at the University of British Columbia (UBC) in Vancouver, specialize in advising individuals and families about genetic disorders.
“Genetics plays a significant role in our health,” states Cremin. “Its importance spans all life stages—from prenatal and newborn phases to pediatric and adult-onset conditions, such as susceptibility to cancer.”
Preventive Functions of Genetic Testing
There exists a complex relationship among genes, environmental elements, and lifestyle choices. “Genetics can either be the primary cause of a condition or just a small factor contributing to it,” explains Cremin.
In cases of single-gene hereditary conditions, where a variant in one gene can be identified as the cause of a disease, a proactive approach is viable. For instance, hereditary breast and ovarian cancer may stem from mutations in the BRCA1 or BRCA2 genes. According to Cremin, established guidelines allow patients with these genetic risk factors to follow enhanced cancer screening protocols and risk-reduction strategies.
Conversely, some genetic testing results are more ambiguous. Often, conditions may arise from multiple genes, influenced by a combination of lifestyle and environmental elements.
Genomic variation—differences in DNA sequences among individuals or populations—can be misunderstood, says Cremin. “Every one of us carries variants in our DNA, many of which are benign. Some variants may slightly affect the risk of certain conditions, while others can lead to serious conditions or significantly raise the risk,” she adds.
Private versus Public Testing
Carol Cremin, MSc, CCGC, explains that there are three primary ways individuals can access genetic testing.
A doctor may refer a patient to a medical genetics clinic based on concerns regarding their personal or family health history, leading to diagnostic genetic testing.
The growing trend of direct-to-consumer (DTC) testing allows consumers to receive results directly. These tests typically examine a limited number of common genetic variants associated with wellness traits (such as hair type) or ancestry, and may also assess moderate genetic health risks, possibly including higher-risk conditions.
However, DTC testing is not considered medical-grade and must be confirmed clinically. Cremin cautions that a normal result from a DTC test does not negate the necessity to investigate family health history for more comprehensive genetic testing options. It’s also vital to research the DTC company’s privacy policy, which should be easily accessible on their website.
A new category termed consumer-initiated provider-mediated testing has emerged recently, where genetic testing companies offer a genetics provider to explain results or oversee the testing process, potentially offering medically actionable results for proactive health management.
Understanding Genomic Medicine
Not all genetic tests are the same.
Genomic Diagnostic Test
This test aims to identify the precise genetic cause of a diagnosed condition, guiding treatment or management decisions.
Predictive/Pre-symptomatic Genetic Test
This test checks for inherited genetic variants that are known to cause specific hereditary conditions within a family. It can clarify whether you are at risk, helping reduce anxiety and inform lifestyle and healthcare choices.
Pharmacogenomic Test
This test reveals how your body processes medications, assisting your doctor in prescribing drugs that align best with your genetic profile.
For those new to genomics, familiarizing yourself with genetic terminology is beneficial. Cremin recommends visiting medlineplus.gov/genetics for reliable information.
Genetics—A Single Piece of the Puzzle
Genetic information represents just one component of a larger picture. Studies on gene-environment interactions have indicated that early experiences can influence gene expression and activation.
Research into the relationship between lifestyle and genetics has also expanded, with nutrigenomics focusing on how genes and nutrition interact.
How Genetic Testing Works
Typically, genetic testing begins with collecting a blood sample or a small saliva sample. Many patients, including those of Andrew Krahn, MD, UBC’s former chief of cardiology and founder of the Hearts in Rhythm Organization, appreciate that most tests are now done using saliva.
After the sample is taken, the genetic material is analyzed for changes that may indicate illness or disease.
Asking the Right Questions
Krahn suggests asking how the outcomes will impact your care and how they may benefit family members. For instance, knowledge gained from grandparents’ genetic testing may help their grandchildren.
Cremin emphasizes the importance of understanding the available support, including genetic counseling, and whether the counselor is certified by respected organizations like the Canadian Board of Genetic Counselling (CBGC) or the American Board of Genetic Counselling (ABGC).
It’s crucial to verify how the testing results will be interpreted. Inquire whether the laboratory conducting the tests is accredited and adheres to established standards and practices for interpreting genetic variations. Laboratories recognized by the College of American Pathologists (CAP) and certified under the Clinical Laboratory Improvement Amendments (CLIA) maintain high-quality standards, says Cremin.
“Without proper accreditation, there can be risks of false positives or negatives, leading to potential harm if best practices aren’t used in interpreting DNA variants,” warns Cremin.
Taking Charge of Your Health
Staying on top of your nutritional needs is essential for healthy aging.
Omega-3 or fish oil supplements can enhance heart health. Research suggests that fish oil may also reduce inflammation in individuals with autoimmune conditions and others.
Additionally, greens powders can support health as you age, offering minerals like calcium and potassium for effective blood pressure management, alongside high levels of vitamin C, known for promoting immune function and preventing heart disease.
This article was originally published in the March 2025 issue of alive magazine.
