How Do Genes Affect Your Health?

How do your genes affect your health?

“There are changes in your DNA sequence, or your genes, that make you more likely to develop a particular condition,” explained Elizabeth Jordan, MS, LGC, a licensed genetic counselor and associate professor of internal medicine at the Ohio State University College of Medicine. When this happens, this is referred to as a genetic predisposition.

Experts have identified many genetic conditions — from cystic fibrosis to sickle cell disease to cancer. For instance, some of these are caused by a single gene while others are multiple gene mutations that together make your risk rise, said Jordan.

What genetic conditions should you know about?

Jordan points to three in particular to put on your radar: familial hypercholesterolemia (the official term for genetic high cholesterol), Hereditary Breast and Ovarian Cancer (HBOC) and hereditary non-polyposis colorectal cancer, called Lynch syndrome.

The Centers for Disease Control and Prevention (CDC) puts these in a Tier 1 category meaning there’s evidence that understanding your risk and taking action can be helpful. “Basically these are conditions that are at high frequency in the general population that not only women, but everybody should know about,” Jordan said.

Let’s take a closer look:

Genetic high cholesterol: Approximately 1 out of every 250 people have this common condition. “If your LDL, or bad cholesterol, is around 190 milligrams per deciliter that usually raises a red flag for concern that this is really more driven by genes rather than just having poor dietary habits,” Jordan said.

Hereditary Breast and Ovarian Cancer: From 5 to 10 out of 100 cases of breast cancer are hereditary and 10 to 15 cases of ovarian cancer are hereditary. The most common genes associated with these hereditary cancers are BRCA1 and BRCA2. Having either gene mutation does not mean you will definitely get breast cancer, but women with a BRCA1 or BRCA2 gene mutation have a higher chance of developing breast cancer by age 80 compared to the average woman.

Lynch syndrome: This genetic condition can increase your likelihood of developing colorectal cancer and several other cancers, including endometrial, stomach and uterine cancers. Lynch Syndrome is estimated to be the cause of 3% to 5% of colorectal cancer cases and 2% to 3% of endometrial cancer, according to the American Society of Clinical Oncology.

With all of these diseases, certain symptoms, family history and age of diagnosis — for example, if you’re under 45 and diagnosed with breast cancer — can let doctors (and you) in on whether genetics might be at play.

Knowing this information can be helpful from both a preventive standpoint, like how Angela had a hysterectomy, and for treatment options. For example, if you know you have a family history of high cholesterol, you will know to ask your healthcare provider about medications tailored to your condition. “I am thrilled to finally be in an era where we have drugs for managing cholesterol that are designed specifically for people with genetic high cholesterol,” said Jordan.

What about mental health conditions?

Research suggests that some mental health conditions may also have a genetic component. For instance, in a 2022 study published in the journal Nature, researchers were able to point to a number of genes that may be associated with schizophrenia.

Conditions such as schizophrenia, depression, anxiety and bipolar disorder are considered complex, Jordan said, meaning that both genes and environmental factors tend to be at play for people that develop them. While some genetic testing does exist, a genetic counselor can go over things like family history, age when symptoms start and assessment options to determine if it’s helpful.