Doctor Decoded: Genetic vs. Hereditary

When your doctor tells you that your condition is genetic, you may feel nervous about your family members: Are they at risk as well?

It’s easy to confuse genetic and hereditary since they both deal with DNA and mutations. In fact, you might even hear people use them interchangeably; however, they are not exact synonyms. 

Genetic diseases refer to any condition caused by one or many gene mutations, as opposed to a disease caused by an infection (like the flu) or a deficiency of nutrients (like scurvy). Your genes can break or alter, causing them to no longer function like normal. When this mutation occurs, it doesn’t automatically cause the disease, but it increases the risk that the disease will develop. 

Examples of genetic disease include Down syndrome, cancers, diabetes, and autoimmune diseases (like psoriasis or inflammatory bowel disease). All of these involve gene mutations — although they may occur in different ways and affect different parts of the body.  

Some gene mutations can be acquired, meaning they occur during a person’s lifetime due to environmental factors. For example, smoking can cause gene mutations that lead to lung cancer, and UV radiation can cause gene mutations in the skin that leads to skin cancer. 

But some gene mutations are inherited from parents — a hereditary disease. Not everyone who inherits a gene mutation will get that disease, but they are at a higher risk of developing it. For that reason, you can also get a hereditary disease that your parents never had — they were merely carriers. 

For example, some cancers are hereditary. Researchers have identified two key genes that help repair DNA to prevent breast cancer, which they have named BRCA1 and BRCA2. Some women have an inherited, mutated BRCA2 gene, which can lead to tumor growth. Of women with a BRCA2 mutation, 50 out of 100 will develop breast cancer before the age of 70, according to the National Breast Cancer Foundation, compared to only 7 out of 100 women who do not have the gene. (Note that not all breast cancers are hereditary.)

Other examples of hereditary diseases include sickle cell anemia, cystic fibrosis, and Down syndrome. 

Remember, in many cases, a gene mutation doesn’t always mean you’re “doomed,” but it does make your risk higher. A healthy lifestyle and safe environment — low in air pollution and other toxins, for example — can help counter a genetic predisposition to certain diseases.

Here are the healthy lifestyle habits that can help you live longer.