Gene

What Genes Are and Why They Matter

Genes are small sections of DNA found in nearly every cell of your body. They act like instruction manuals, telling your body how to make proteins that are essential for growth, repair, and normal function. You inherit two copies of each gene—one from each parent. These inherited genes influence many traits, including your risk for certain diseases.

Sometimes, genes can have changes called mutations or variants. These changes can happen naturally over time, be caused by environmental factors, or be inherited from your parents. Some gene changes do not cause any problems, but others can increase the chance of developing diseases like cancer.

Genes and Cancer Risk

Cancer is often described as a genetic disease because it involves changes in genes that control how cells grow and divide. Some gene changes happen only in cancer cells and are not inherited. However, some gene changes that increase cancer risk can be passed down through families. For example, inherited changes in genes like BRCA1 or BRCA2 can raise the risk of breast and ovarian cancers.

Knowing about inherited gene changes can help you and your healthcare provider make informed decisions about cancer screening, prevention, and treatment. Genetic testing can identify these inherited changes, especially if you have a family history of cancer.

What Genetic Testing Means for Patients

Genetic testing looks for changes in your genes that might increase your risk of cancer or other diseases. This testing usually involves a blood or saliva sample sent to a lab. It can help identify inherited gene changes that run in families. However, not everyone needs genetic testing. Your healthcare provider can help decide if testing is appropriate based on your personal and family medical history.

It’s important to understand that having a gene change does not guarantee you will develop cancer, only that your risk may be higher. Likewise, not all cancers are caused by inherited gene changes. Many cancers happen due to gene changes acquired during life.

How Genes Are Used in Cancer Care

Doctors may use information about genes in several ways. Genetic testing can guide decisions about cancer screening and prevention for you and your family. In some cases, testing tumor cells for specific gene changes can help choose targeted treatments that attack cancer cells more precisely. This is different from inherited genetic testing and is called biomarker or tumor profiling.

Understanding gene changes can also help doctors monitor how well treatment is working or if cancer might come back. Genetic information is one part of a larger picture that includes your health history, symptoms, and other tests.

Questions to Ask Your Care Team

If you hear about genes or genetic testing in your care, you might ask: Do I have a family history that suggests genetic testing? What would genetic testing involve? How could the results affect my care or my family’s health? What are the risks and benefits of testing? How will my privacy be protected? Your healthcare provider can help explain what genetic information means for you personally.

Understanding the Limits and Next Steps

Genes are an important part of understanding health and cancer risk, but they are not the whole story. Lifestyle, environment, and chance also play roles. Genetic testing is a tool to help guide care but does not provide all the answers. This information is educational and cannot replace personalized advice from your healthcare team.

If you think genetic testing might be helpful, talk with your doctor or a genetic counselor. They can help you understand the benefits, risks, and what the results might mean for you and your family.