Genetic research has contributed massively to the ongoing successes within the field of cancer prevention and treatment. The details of how genes work as part of the body and their role in cancer development are complex and still not completely understood, however researchers continue to explore this area to find possible answers. Understanding the genetics of cancer requires looking at the basics of genetics and how gene mutations impact the body. Here you’ll find an overview of how genes and cancer are related.
What is Genetics?
Genetics is the study of genes. Genes make up DNA and provide instructions to create molecules in the body and are passed on to an individual from each of their parents. This is why families share similar traits, both visible and internal. Just as someone might receive the genes for brown eyes from their parents, they may also receive mutated genes that increase their chances of contracting specific cancers. Genes can also become damaged, again leading to an increased risk of cancer.
Types of Gene Mutations
The hereditary types of genetic mutation that come from your parents are called germline mutations. Only one parent needs to carry the mutated gene for it to be passed on to the embryo during gestation. Just because someone carries the mutated gene doesn’t automatically mean that they’re guaranteed to contract cancer, even though it increases their risk.
More common than germline mutations, acquired mutations are when genes become damaged during a person’s lifetime. Instead of being passed down from parents, the gene mutates due to other factors such as viruses, age, smoking, or radiation. Since genes instruct the creation of molecules, they dictate the growth of cells. A mutated gene may fail to halt cell growth and allow a tumor to form.
Genetic Testing for Cancer Risk
One of the major improvements in cancer prevention that has arisen through recent research is the possibility of identifying individuals with higher chances of developing certain cancers. This is through genetic testing, which analyzes changes in a person’s chromosomes, genes, and proteins. Cancers that can be detected through genetic testing include:
- Breast cancer
- Pancreatic cancer
- Colon cancer
- Prostate cancer
- Ovarian cancer
- Thyroid cancer
Genetic testing detects gene mutations that increase a person’s likelihood of developing the disease. This doesn’t mean the person will definitely become ill, just that the chances are higher. Genetic testing allows people with this higher risk to take better and more informed precautions regarding their health.
Not all cancers can be predicted through family history or genetic testing. Some types of leukemia, for example, have no family indication. This is why it’s so important to look out for signs of leukemia. However, people who are closely related to others who have leukemia tend to be at an increased risk for the disease. Blood tests are the main method of diagnosing leukemia, whereas the chances of developing other cancers can be detected through genetic testing.
Types of Genetic Testing
Just as there are many types of cancer, there are multiple forms of genetic testing. These each serve their own purpose and are used in different circumstances for different people. They can find specific mutations and make time for early treatment measures.
- Predictive genetic testing determines how likely a person is to develop a specific form of cancer based on their genes. People with a family history of cancer can use genetic testing results to guide their strategies for prevention.
- Genetic counseling aims to address the emotional and psychological implications of genetic testing. Families and individuals can suffer unexpected consequences after getting their genetic test results and genetic counseling offers clarity and support to make sensible health decisions for the future.
- Preimplantation Genetic Diagnosis, also known as PGD, allows people seeking IVF treatment to identify embryos without cancer mutations for implantation. This decreases their child’s chances of receiving hereditary cancer genes from their parents.
Who is Genetic Testing Right For?
People who have a personal or family history that indicates a possible higher risk should consider genetic testing. Not all cancers are hereditary and can’t be detected this way, so genetic testing should never be viewed as a method of completely avoiding cancer of all kinds. It’s intended as being a source of information for people who want to make health and lifestyle decisions to reduce their risk.
Risks of Genetic Testing for Cancer
Despite the huge benefits that genetic testing has brought to the field of cancer research, there are several potential drawbacks that must be considered. Some people who receive results from genetic testing that show gene mutations can feel the stress of illness without a real cancer diagnosis. Sometimes the knowledge of increased risk causes anxiety rather than reassurance. On the other hand, genetic testing can give some people a false sense of security. Genetic testing should be seen as a way to gain more detailed information about your health, not as a diagnosis or as a guarantee against developing cancer.
How Genes Combat Cancer
Although there can be mutated or damaged genes that lead to cancer, the body is equipped with various types of genes that defend against it. When these are damaged, the risk of cancer increases. Tumor suppressor genes limit the growth of cells to prevent tumors from forming. They correct errors in DNA, control how quickly cells divide, and control when a cell dies. DNA repair genes identify and fix mistakes that occur when cells divide and DNA is copied into the new cells. Similar to tumor suppressor genes, these DNA repair genes restrict how much a cell can grow and replicate. Damage to a DNA repair gene can also lead to cancer.
Genetic Research and Cancer Treatment
When cancer treatment is more focused on the individual, it’s more successful. Genetic testing and research have improved the personalization of cancer treatments for patients all over the world. Targeted therapies, precision surgery, and immunotherapy have all been positively impacted by ongoing genetic research.
This area of medicine is constantly changing due to dynamic and urgent research leading to advances in prevention and treatment. As scientists understand more about how genetics and cancer are related, hopes for solutions become increasingly realistic.