In our health conscious age, these do-it-yourself DNA tests can seem appealing. But is it always a good thing to have all this knowledge and information at our fingertips?
Why have a genetic test?
There are many reasons you might be looking to have a genetic test. Here are some of the main ones.
- Diagnosing a condition. If you or your child have symptoms that could be caused by an inherited condition, having a genetic test can determine this.
- Family history of a disease. Maybe you have a strong family history of an inherited disease, such as breast cancer or bowel cancer. A genetic test could determine whether you carry the genes that would put you at risk of developing these diseases. An example is the BRCA gene for breast cancer.
- Screening and diagnosis in pregnancy and babies. Having a baby may be the first time you really need to think about genetic testing. Genetic tests can let you know if your baby has, or is likely to be born with a specific condition or syndrome. One condition that your doctor can test for is Down’s syndrome. For more information see our topic page Prenatal screening and diagnostic tests for Down’s syndrome.
- Improve lifestyle. There are now a suite of tests on the market that claim to be able to personalise your lifestyle and diet using genetic tests.
- Just curious. More and more people are looking to have genetic tests just out of curiosity. And with the ease with which you can now order these tests, it’s an enticing prospect.
How much is down to your genes?
Whatever your reason for having a genetic test, it’s important to keep in mind that your genes don’t give you the whole picture. Even if a test reveals certain mutations (changes in your genes) that might increase your risk of a disease, there’s still no certainty of if or when the disease will develop. Most medical conditions are caused by complex interactions between groups of genes, and environmental factors. For instance, even if you have inherited the BRCA gene for breast cancer, your lifestyle will still affect if or when you develop it.
How will my genetic data be used?
Many people worry about whether their genetic information may be used against them in some way, for instance, to increase their insurance premiums. But this isn’t true. Currently, insurance companies are prevented from using an individual’s genetic data through a “moratorium” (a temporary ban) put in place by the Government.
There’s no knowing whether this may change in the future. But we’re still a long way away from genetic tests being sophisticated enough to predict exactly if or when people may get a disease. With lifestyle a major factor, it may never be possible to do so.
What are the pros and cons of having a genetic test?
It’s very much a personal choice whether to have a genetic test. Every scenario – whether you have a family history of a genetic condition or are “just curious” – will carry its own pros and cons. You’ll need to think carefully about your own reasons for having the test, and how you’ll deal with the results. Below are just a few of the benefits and limitations of having a genetic test.
- Knowing for certain you or your child has a condition may mean receiving the most appropriate and effective treatment.
- Finding out you’re at risk of having a child with a certain condition can give you time to think about your options, or prepare before having a child.
- You may value knowing you have a higher risk for a certain condition. It may give you incentive to take measures (for example, changing your lifestyle) to reduce your risk.
- Knowing you have a condition doesn’t necessarily mean there will be a treatment available, or that it will change the outcome.
- Knowing you’re at risk for a condition doesn’t mean you’ll definitely get it. And there’s no way of knowing when you may develop symptoms or how severely you’ll be affected.
- Finding out you have a higher risk for a disease may make you worry and feel anxious. You may prefer not to have this knowledge.
How do I get a genetic test?
This depends on the reason you’re having a test. In many cases, your GP may be able to refer you to NHS genetic services; for instance if it’s to diagnose a condition, or if you have a strong family history of a disease. There are a number of private providers that also offer genetic tests. It’s important to check that they are accredited and registered by the Care Quality Commission.
You can also purchase genetic test kit yourself. These are often mouth swabs that you do at home and need to send off to a laboratory. It’s questionable how accurate these tests are, and without input from a health professional it can be difficult to understand what your results mean.
What does a genetic test cost?
This really varies on the type of test you’re having. You may be able to have some tests through NHS genetic services. Tests that you have privately or that you order directly yourself may vary from hundreds to thousands of pounds.
Should I have a genetic test?
So should you have a genetic test? The reasons for having one are so varied, and everyone’s circumstances so different, the only person who can really answer this is you. My main piece of advice is to be informed and think properly about your reasons for having one before you make your decision. Knowledge can be power – but in some cases, ignorance can be bliss.