Genetic Testing: Understanding Your Risks, Options, and Implications

Written By: Sahannah Seemungal

Do you know of a condition that occurs in your family and you would like to know whether you are at risk of developing it, too, or of being a carrier of a gene that causes a particular disorder, such as sickle cell anemia or cystic fibrosis? Perhaps you simply want to learn about your disease risk because knowing will make you feel better. Genetic testing is a medical test that examines your genes—the DNA instructions inherited from both parents—to identify potential health risks, guide treatment choices, or assess responses to treatments.

There are three main types of genetic tests: single gene testing, panel testing, and whole genome sequencing. Single gene tests consider one gene and confirm or rule out a particular diagnosis, mostly in situations where multiple mutations in such a gene might result in the condition under concern. On the contrary, panel tests consider several genes simultaneously, especially in those situations where symptoms could be from various diseases or one disease due to several gene mutations. For example, there are many genetic causes of epilepsy, so panel testing is a very useful diagnostic approach. Whole genome sequencing is a more general approach, analyzing the bulk of a person's DNA. It tends to be used when other testing has not provided a clear diagnosis, or if the genetic causes of the condition are not well understood. Also, this specific type of testing can be less expensive overall because it may reduce the number of tests a person needs.

Genetic testing, whether it proves to be positive or negative for a mutation, has many advantages. It may remove any kind of fear or questions people have towards a particular illness in case such an illness runs in their family. It allows for early treatment and, more importantly, allows the person to prepare mentally, emotionally, and financially for what is going to happen. Other considerable benefits are the recommendations by healthcare professionals of some preventive measures or changes in lifestyle, including alternative diets or more exercise to prevent certain diseases. This might also include early and more frequent screening, which could, in itself, improve long-term health outcomes.

On the other hand, there are some drawbacks to genetic testing. Tests can be expensive, with some “less than $100 and others more than $2,000”, some of which may or may not be covered by insurance (National Human Genome Research Institute). Moreover, learning that you, or a loved one, is at an increased risk for a condition may be difficult to accept emotionally if it comes as a surprise. Additionally, some genetic tests will not give straightforward results. A positive result means a variant in a gene has been identified that could increase disease risk, but having the variant does not always mean the disease will occur. Most gene variations do not noticeably affect health, and it is often hard to predict what effect a variant will have. Even when positive, the severity and time of onset of symptoms can be unclear, leaving patients with limited information to make informed decisions. 
 

Genetic testing results can be complex, hence, geneticists and genetic counselors can explain the implications of such results. They assist in informed decision-making for personal and family health benefits. These specialists can provide coordinated care subsequent to testing in order to interpret results, establish appropriate management, and develop treatment plans consistent with personal, family, and financial considerations.

References:

"Genetic Testing." Mayo Clinic, Mayo Foundation for Medical Education and Research, https://www.mayoclinic.org/tests-procedures/genetic-testing/about/pac-20384827. Accessed Jan. 6, 2025.

"Genetic Testing FAQ." National Human Genome Research Institute, U.S. Department of Health and Human Services, https://www.genome.gov/FAQ/Genetic-Testing. Accessed  Jan. 6, 2025.

"What Are the Different Types of Genetic Tests?." MedlinePlus, U.S. National Library of Medicine, https://medlineplus.gov/genetics/understanding/testing/types/. Accessed  Jan. 6, 2025.