4 Myths About Medical Genetics

Genetics is a relatively new science in the grand scheme of things. It’s also really complicated, so it’s not surprising that some people may have misconceptions about it. Here are 4 myths about medical genetics and why they’re not true.

Myth #1: If it’s genetic, there’s nothing you can do about it. 

Just because a condition is genetic, doesn’t mean that it can’t be managed or changed. Many genetic conditions have effective treatments. Some metabolic conditions (where your body can’t process certain proteins, fats, or sugars properly) can be treated by being careful not to eat certain foods. There are procedures or medications that can lower the risk of cancer in those who have hereditary cancer syndromes. Our understanding of genetics has lead to the development of medications designed to block the effect of certain genetic changes. There are even real-life gene therapies that are starting to become available to change the DNA itself.

Myth #2: I don’t need to see a genetic counselor because I don’t want that test. 

Some people think that that there’s nothing to gain from seeing a genetic counselor because they’re not interested in a certain test or procedure. I’m possibly (definitely) biased here, but seeing a GC can be beneficial even if you don’t have any genetic testing at all. We can identify risks you may not have realized you have, and offer ways to lower or manage those risks. We also can answer questions about testing and address any concerns or fears you might have. There may be alternative tests or other options you may not have been aware of. 

Genetic counselors pride ourselves in being “non-directive”— letting you decide what is best for you. We don’t make commission from your testing, and we won’t be offended if you don’t want any tests. We DO want to make sure you are aware of all your options, which always includes doing nothing. 

Myth #3: If the test is normal, I definitely don’t have it. 

Genetic technology has made amazing improvements over the last few decades, but it’s still not perfect. Every test has limitations, and even our best tests can miss rare types of genetic changes. There are certain genes that have structures that make them very difficult to read with our current technology. And then there’s the problem of pseudogenes— genes so similar to another gene, that it makes it hard for us to tell which one we’re reading!

We also don’t have a complete understanding about how all the different parts of the genome interact with each other. A lot of what used to be called “junk DNA”— the non-coding areas between genes— turns out to be very important in regulating how genes are expressed. A bit of code in one part of the genome can have an effect on a very distant gene. There are about 20,000 known genes in the human genome, but that only makes up about 1% of our DNA. There’s still a lot of work to be done to understand the other 99%.  

Myth #4: Genetic test results can’t change. 

While it’s true that the DNA you’re born with won’t change over the course of your life (cancer and other somatic events aside), that doesn’t mean that our understanding of your DNA won’t change. Sometimes a genetic test reveals a “variant of uncertain significance,” or a difference in your DNA that isn’t clearly understood yet. As time goes on and more research is done, we may discover that the difference can cause a genetic condition, or it may turn out to be nothing.

Genetic laboratories routinely review new scientific literature to make sure their reports include the most up-to-date information. This sometimes means re-writing a report issued in the past to change the result, even though that person’s DNA hasn’t changed. This doesn’t mean the lab made a mistake the first time— it’s actually a sign of a responsible lab. It shows that the lab is dedicated to looking for new information and willing to notify providers and patients of those updates.

It’s a good idea to ask your provider every so often if there are any testing updates you should know about, especially if you had one of those uncertain results. Some labs are willing to review your particular report for updates upon request. There are also new services, like My Gene Counsel, that will update you automatically when new information about your genetic change is discovered.