How Your Genes Impact Your Risk for Common Health Issues

When you discuss health with your friends, it is likely that you’ll hear something as to how a particular disease or ailment “runs in their family”. The complete picture may be somewhat more complicated because genes impact your risk for common health issues. This is why it is important to identify one’s genetic predispositions, as it can be helpful in remaining proactive and reducing the risks of developing certain health conditions. Here is what you can do to remain healthy and whether or not you will benefit by meeting a genetic counselor. 

Heart disease

It may be somewhat tricky to find whether you are genetically predisposed to cardiovascular disease. This is partly because heart disease is a very broad category. Knowing that some of your family members died of heart disease is only the first step to determine the probability of genetic inheritance. Studies have shown that some heart issues have more of a genetic component than others. 

In fact, you may even “inherit” some of your lifestyle habits from your family, along with your genes. 

Your physician or genetic counselor will be able to assess better the heart disease that might afflict you when you share more information about your family history and your lifestyle with them. This is because we all “inherit” some of our lifestyle habits from our families, along with our genes. For instance, our diet makes a big difference to our heart disease risk. It is perhaps influenced by how one grows up eating, and whether he/she still eats that way.

Breast cancer

Most of us are aware of the BRCA1 and BRCA2 mutations – thanks to celebrities like Christina Applegate and Angelina Jolie. If a woman inherits these mutations from her mother or father, it may augment her risk of developing breast cancer by 70%. However, there are chances that one may develop these mutations on the PIK3CA gene randomly. This has been found in some women suffering from breast cancer. 

Joy Larsen Haidle, a cancer genetics expert for the National Society of Genetic Counselors, says, “We’ve known BRCA for a long time and we understand the cancer risks that go with it,” adding, “There are very specific surveillance recommendations and there are very specific risk-reduction options that people can think about.” However, this is not the case with PIK3CA, which may tell us more about how a patient might respond to treatment, instead of her likelihood of getting breast cancer in the first place, says Larsen Haidle.  

In addition, a genetic counselor can help you in putting the puzzle pieces together for a full picture of your risk for breast cancer. For instance, says Larsen Haidle, without testing, it may appear that gene mutations related to breast cancer don’t run in your family, because cancer doesn’t run in your family. However, it might be that women in your family had hysterectomies for various reasons, which lowered their risk, and they still had the gene. A genetic test can tell you for sure. 

Autoimmune diseases

A number of health conditions have a hereditary genetic link, but they only manifest later in life, especially when a particular event sparks them. For instance, in the case of autoimmune conditions, the genes you inherit may egg your immune system to get confused and attack itself if triggered by something in your environment. However, your genes are not linked to any specific autoimmune disease. Type 1 diabetes and autoimmune thyroid disease can have the same underlying genetic susceptibility, but attack two different people in two different parts of the body. You may see autoimmune diseases cluster in families, but they aren’t necessarily clusters of a single disease. There are definitely inherited genetic factors, but it’s not as simple as you got the ulcerative gene from your father. 

For example, inflammatory bowel disease (IBD), which includes autoimmune conditions like Crohn’s disease and ulcerative colitis, develops later in life, and one’s DNA plays a role in it. There are definitely inherited genetic factors, but it’s not as simple as you got the ulcerative colitis gene from your dad. You’re not born with the condition. There’s probably something going on with the immune system in your gut that gets activated, leading to someone with a genetic predisposition for IBD to develop it. Behaviors like smoking, eating certain foods, taking medications; or even stress could trigger it. 

Autism

Autism is a complex health condition and presents itself in various ways along the autism spectrum. According to Wendy Chung, Kennedy Family Professor of Pediatrics and Medicine, Chief of Clinical Genetics at Columbia University, all types of autism are a result of genetic makeup, but the disorder is not always passed down through families. Often, individuals who are at the quote-unquote higher-functioning end of the spectrum will cluster within families more than individuals who might be nonverbal, self-injurious, or have a lot of significant issues. People with those kinds of challenges seem to appear more sporadically in families, so genetic testing for the disorder isn’t generally recommended. 

Alzheimer’s disease

When it comes to Alzheimer’s disease, certain families exhibit clear hereditary or genetic factors that result in multiple members having Alzheimer’s. However, that’s not always the case. Everyone receives a version of the apolipoprotein E (APOE) gene on chromosome 19 from both their mother and their father. One particular variant, APOE ε4, increases your risk of developing Alzheimer’s disease. But even if you have this variant, and your risk is higher because of it, it does not put your risk at 100%. The lifestyle choices you make also have a big effect on your risk, even if you have a certain mutation. Regular mental stimulation and weekly exercise can both help to maintain brain health and reduce Alzheimer’s risk.