Genetic testing is often recommended for patients with certain health conditions like cardiovascular diseases, cancer, and autoimmune disorders. Whether you’re testing on the recommendation of your doctor or you opt to undertake it on your own, your approach to genetic testing matters.
Genetic counsellors, like Carol Cremin, MSc, CCGC are specialized healthcare providers trained to provide guidance to individuals or families about genetic disorders.
“Genetics play a huge role in our health,” says Cremin. “It’s really important throughout all stages: from prenatal, newborn, and pediatric conditions to adult-onset conditions, like cancer susceptibility.”
Genetic testing’s preventive role
There is a complex interaction between genes, environmental factors, and lifestyle. “Genetics can be the main cause of a condition, or a small piece of the puzzle for others,” says Cremin.
With single-gene hereditary conditions, where a variant in one gene can be pinpointed as a cause of a disease, a very proactive approach can be taken. For example, hereditary breast and ovarian cancer can be driven by a problem in the BRCA1 or BRCA2 genes. There are clear guidelines, says Cremin, that patients can follow for enhanced cancer screening and risk-reduction options if they have one of these genetic risk factors.
In other cases, the results of genetic testing are not as clear-cut. Often, the causes may be influenced by multiple genes, along with a mixture of lifestyle and environmental factors.
Genomic variation―the DNA sequence differences among individuals or populations―is often misunderstood, says Cremin. “We all carry variants in our DNA code, and many of these variants are harmless. Then there are variants that may have a very small impact on risk for certain conditions, whereas others can either cause a condition or a very strong risk for a condition.” she says.
Getting to know genomic medicine
All genetic tests are not created equal.
Genomic diagnostic test
A diagnostic test is designed to pinpoint the exact genetic basis of a condition you may have been diagnosed with. This can help guide your choices about how you treat or manage your health.
Predictive/pre-symptomatic genetic test
This type of test will examine if you have inherited a genetic variant that is known to be the cause of a specific hereditary condition in your family. This testing can clarify if you are or are not at risk, which may reduce uncertainty and assist in your lifestyle and healthcare decisions.
Pharmacogenomic test
This test illuminates how medicines are processed by your body, and it helps your doctor prescribe the medicine that works best with your genetic makeup.
To learn more, genomics rookies may want to start by brushing up on their genomic and genetic vocabulary. Cremin suggests checking out medlineplus.gov/genetics as a reliable source of information.
Taking your health into your own hands
Keeping on top of your nutritional needs is also key to healthy aging.
Omega-3 or fish oil capsules can boost your heart health. Research is also accumulating to support the finding that fish oil supplementation might lessen inflammation in people with autoimmune disease (as well as those without).
Further, greens powders can help you tend to your health as you age, as they can contain minerals like calcium and potassium, which are associated with good blood pressure management, and a high vitamin C content, which has been associated with healthy immune system function and heart disease prevention.
Genetics―just one building block
Genetic information can form one piece of a larger puzzle. For example, the study of gene-environment interactions has revealed that early experiences may dictate how genes are turned on and off and also whether or not they are expressed.
The interplay of lifestyle and genes has also been the subject of research, while nutrigenomics is the study of how genes interact with nutrition.
How genetic testing works
Typically, genetic testing starts with the collection of a blood sample or a small amount of saliva. However, many patients of Andrew Krahn, MD, founder of the Hearts in Rhythm Organization, are happy that the majority of testing is now performed through saliva.
Once a sample has been extracted, the genetic information from the cells is examined with an eye for changes in the genes that may cause illness or disease.
Asking the right questions
Krahn suggests asking how the test results will change your care. He also encourages individuals to inquire about how it will help members in their family. For instance, grandparents may undergo genetic testing because it may help their grandkids.
According to Cremin, it’s also important to ask what type of support is going to be available, whether or not they offer genetic counselling, and whether that counsellor is certified by the American Board of Genetic Counselling.
It’s also very important to understand how your genetic testing is being interpreted. You should ask if the testing facility is a qualified, accredited lab and whether they follow standards and guidelines for best practices in interpreting genetic variation.
Labs that have accreditation by the College of American Pathologists and Clinical Laboratory Improvement Amendments certification must meet high quality standards, says Cremin.
“Without that, there’s the possibility of false positives and false negatives. There is a potential for harm if best practices aren’t followed in interpreting variants in the DNA sequence,” says Cremin.
In the complex world of genetic medicine, ensuring you get the highest quality of information, provided by experts, is essential.
Private vs public testing
Individuals can access genetic testing in three main ways, explains Carol Cremin, MSc.
A doctor may refer the patient to a medical genetics clinic due to a concern in their personal health or family health history. This can lead to diagnostic genetic testing.
There has also been a huge global uptake in direct-to-consumer (DTC) testing, says Cremin. Here, the results typically go straight back to the consumer. These tests look at a limited number of common genetic variants that have been associated with a broad range of wellness or personal traits (like hair type) or ancestry. Some DTC tests may also test for moderate genetic health risks and can include―with limitations―higher-risk conditions as well.
DTC testing is not medical grade and would still need to be clinically confirmed. The results of a DTC test cannot be used to rule out the risk for a condition, warns Cremin. “If it’s normal, it doesn’t replace the need to look deeply at your family’s history to decide whether more comprehensive genetic testing should be considered.”
With a DTC company, it’s also important to research their privacy policy, which should be readily available through their website.
A middle ground, called consumer initiated-provider mediated testing has emerged within the past few years. Here, the testing company offers a genetics provider to help explain the results to the patient or place the test―which may be medical grade―and can provide medically actionable results for patients who want to be proactive with their health.
Taking your health into your own hands
Keeping on top of your nutritional needs is also key to healthy aging.
Omega-3 or fish oil capsules can boost your heart health. Research is also accumulating to support the finding that fish oil supplementation might lessen inflammation in people with autoimmune disease (as well as those without).
Further, greens powders can help you tend to your health as you age, as they can contain minerals like calcium and potassium, which are associated with good blood pressure management, and a high vitamin C content, which has been associated with healthy immune system function and heart disease prevention.
