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The world of genetic testing has opened the door to possibilities previously thought impossible. DNA tests can reveal unknown diseases and help doctors find more effective treatments.
The benefits of knowing how sickness affects your life can be significant, but it’s not always for the best. It’s essential to know the pros and cons of genome testing before making what could be one of the most crucial decisions for you and your family.
A genetic test is a medical procedure that identifies changes and mutations in the chromosome, genes, or protein of your DNA which might indicate a potential for future disease, illness, or abnormality.
DNA tests can find diseases such as certain cancers, heart disease, Alzheimer’s, and diabetes, to name a few. Genome testing can also trace the ancestral history of a person’s family.
There are several benefits to genetic testing when focused on your health, the health of a family member or unborn child, or looking for answers into your past.
If you want to know more about your future health risks, especially if certain diseases are common in your family, a health DNA test may provide the right answers for you. These tests are for patients with a history of a particular illness or already suffering symptoms from a disease.
Genome testing can identify DNA changes resulting in a higher risk of developing certain medical conditions like breast cancer or sickle cell. Knowing you have a positive test allows for preventative treatment or even early detection of disease.
Doctors can also use genetic testing for patients with mysterious and unknown symptoms. A mutation in the gene along with a patient’s health history allows physicians to identify specific illnesses. Medical personnel’s ability to use genome testing and data technology such as healthcare informatics improves patient care and health care outcomes.
Studies show that about 20% of the population have some genetic deformity and are at risk for certain diseases [1]. Knowledge of your DNA structure will allow you to make medical decisions for yourself and your family.
Adults with the genetic mutation for early-onset Alzheimers have a 50% chance of passing the mutation on to their children. If the child has inherited a variant, they have a much higher risk of developing the disease [2].
Ovarian cancer and breast cancer are both linked to the BRCA 1 and BRCA 2 gene. 5-10% of people diagnosed with these cancers have inherited the genetic mutation of one of these genes [3].
BRCA mutations significantly increase the risk of breast and ovarian cancer
Knowing that you don’t have a particular gene mutation can alleviate stress and anxiety. Testing negative for BRCA mutation will allow you to let go of fear, especially if you have a history of cancer in your family.
If you have symptoms similar to a particular illness doesn’t necessarily mean you have that disease or will contract it in the future. Seeing a negative test result will help you and your doctor look deeper for answers regarding your health.
Whenever changes within the gene occur, you’ll be able to take early action to prevent illness. For example, both Type 1 and type 2 diabetes are inherited conditions, but environmental factors trigger the disease [4].
Once you know that you have a predisposition for diabetes, you can prevent the onset by changing your lifestyle, adding more exercise in your daily routine, or incorporating more fruits and vegetables into your diet. Doctors may also prescribe preventative medications, vitamins, and nutrients.
All family members share DNA, and results from your genetic testing can give greater insight into your entire family’s health.
Parents, children, and full siblings share 50% of their DNA. Grandparents, Aunts, Uncles, and Cousins share 25%, and if you are an identical twin, you share 100% of your DNA [5].
Positive results on a genetics test likely mean that the same mutation will be in other family members. Understanding the changes found in DNA will help doctors identify which test is best for each family member and expedite finding diseases in others.
There’s an option for pregnant women to undergo genetic screenings or tests to detect the possibility of congenital disabilities or birth defects. Prenatal screenings will reveal the chances of you passing on a genetic mutation to your child, but prenatal diagnostic tests look at the cells of the fetus or placenta to detect if your child is positive for specific disorders.
If you’re in the first or second trimester, between 11-20 weeks of pregnancy, you have the option of the following screenings:
Detection of a problem can lead to further testing, and your doctor may order one of the following diagnostic tests:
Pregnant women have a higher risk of their child being born with genetic abnormalities if they are:
Advanced maternal age increases the risk of having a baby with Down syndrome
Women are usually offered the option of genetic screening and tests at some point during their pregnancy. Taking these tests is optional, but it can be a comfort to know if your pregnancy is at risk.
After a birth defect diagnosis, prenatal surgery and medications for treatment during pregnancy are possible. Unfortunately, most treatment options aren’t available until after the child is born, including surgical procedures, physical therapy, and assisted devices.
Sometimes, doctors cannot determine disabilities until later in the child’s life or into adulthood. Congenital anomalies detected early can give parents and family more time to prepare for future life-style changes and treatment plans.
Fetal surgery, a medical procedure done on the fetus before birth, is rare and only advised if there’s a health risk to the mother, the child has a life-threatening condition, or if treatment is not possible and would have little effect after the child is born.
Genetic, or ancestry testing, is a way for people to discover more about their family history and dive deeper into their past beyond information from relatives or historical documentation. These tests can determine precisely where a person’s ancestors come from and their relationships to one another.
Ancestry testing is beneficial for anyone questioning their parentage—a child and father or anyone in the world of adoption looking for a parent or child. These tests also identify siblings, cousins, grandparents, and other relatives.
Genetic testing is very personal and isn’t the right decision for everyone. It’s essential to know the negative impacts of DNA testing before taking the first steps.
Some question the efficacy of genetic testing for a variety of reasons. If a mother finds out that her unborn child is suffering from a severe health condition or congenital disability, there may be pressure to terminate the pregnancy. The stress of that decision is hard enough for the mother, but the societal pressure affects any decision made.
Physicians also face an ethical choice when finding potential health issues in patients who cannot afford treatment. How do you inform a patient of a life-changing illness and decide the next steps if treatment isn’t possible?
Genetics tests sometimes provide false-negative or false-positive results. When this happens, it’s crucial to fully consult with a genetics counselor to understand the testing and determine further action. At-home tests, which most people use for ancestry, can also give inaccurate or misleading results.
There’s a minimal risk of miscarriage when undergoing a prenatal test, especially a test that involves removing amniotic fluid. Other risks involved are more emotional. Knowing that your child has a defect can cause unnecessary anxiety to the mother, resulting in a more stressful pregnancy.
Just because you have a marker indicating a possibility of illness doesn’t mean that the disease will, in fact, manifest. For the most part, genes play only a small role in how long you live, accounting for 20-25% of why you make it to a certain age [6].
There’s also the possibility of being in your 30’s and 40’s and receiving a positive result of a disease that potentially won’t affect you until much later in life. Spending decades wondering if and when a condition will materialize can cause stress, anxiety, and even depression.
Even though you’ve decided to get tested doesn’t mean your family members will be as enthusiastic to know their potential health issues. Not every family member shares the same genes, and therefore not all variants will be the same.
You can have a mutation in your genes that other family members don’t possess. Or you find a defect passed onto your children, and now you find yourself filled with guilt over something you have no control over.
There are thousands of genes in the human body, and there’s no way for doctors to test for every possible medical condition. Testing is limited to those already suffering from disease or have a family history of certain disorders and illness. Unfortunately, you’re not eligible for genetic testing merely due to fear of a particular disease.
Your doctor will take samples of your blood, skin, or hair. If doing prenatal testing, a specialist will take a tiny piece of the placenta or a small amount of the amniotic fluid surrounding the baby.
Patient samples are tested in a laboratory where technicians examine each one for changes in the chromosome, cell protein, or DNA. The lab will then send the results to a doctor or genetic counselor for review.
This question doesn’t have a simple yes or no answer. The only way to decide if genetic testing is a good idea is to have all the information necessary to make the best decision.
Your doctor will determine if genetic testing is a reasonable possibility. They will then advise you to speak with a genetics counselor—a medical professional trained to interpret genetic tests and counsel patients on all options available.
Gene therapy is a medical treatment that modifies or replaces defective genes for healthy ones. This procedure can treat diseases in the body or stop them in their tracks.
Gene therapy is still experimental, and the long-term effects are not yet known. There’s research to show that gene therapy can lead to a worsening of symptoms in certain health conditions. Unfortunately, there’s not enough testing or evidence to make any definitive conclusions.
Genetic testing has come a long way and has many benefits in the world of medicine. DNA tests can find illnesses that might have otherwise gone undetected in the past. Doctors now have better insights into how to treat patients effectively, and patients know how best to live their lives.
DNA testing information is useful in improving medicine, but everyone should view genetic testing with caution. These tests are not for everyone, and patients should take them very seriously.
Knowing that you have a specific condition can change your life for the better or worse. It’s important to look at all sides of genetic testing before you decide how you want to move forward.
1. Rego, Shannon, et al. “High Frequency Actionable Pathogenic Exome Mutations in an Average-Risk Cohort.” BioRxiv, Cold Spring Harbor Laboratory, 1 Jan. 2017, www.biorxiv.org/content/10.1101/151225v1.
2. “Alzheimer’s Disease Genetics Fact Sheet.” National Institute on Aging, U.S. Department of Health and Human Services, www.nia.nih.gov/health/alzheimers-disease-genetics-fact-sheet.
3. “BRCA1 & BRCA2 Genes: Risk for Breast & Ovarian Cancer.” Memorial Sloan Kettering Cancer Center, www.mskcc.org/cancer-care/risk-assessment-screening/hereditary-genetics/genetic-counseling/brca1-brca2-genes-risk-breast-ovarian.
4. “Genetics of Diabetes.” Genetics of Diabetes | ADA, www.diabetes.org/diabetes/genetics-diabetes.
5. Wallace, Susan E, et al. “Family Tree and Ancestry Inference: Is There a Need for a ‘Generational’ Consent?” BMC Medical Ethics, BioMed Central, 9 Dec. 2015, www.ncbi.nlm.nih.gov/pmc/articles/PMC4673846/.
6. “Is Longevity Determined by Genetics?: MedlinePlus Genetics.” MedlinePlus, U.S. National Library of Medicine, 18 Sept. 2020, medlineplus.gov/genetics/understanding/traits/longevity/#:~:text=Longer%20life%20spans%20tend%20to,genes%20is%20a%20developing%20science.
