Genetic testing: Unlocking the secrets of your health

Imagine being given a glimpse into your future health. What might it tell you?

If you discovered you're at a higher risk of developing type 2 diabetes, you might take early action to improve your diet, exercise more or monitor your blood sugar.

These changes may help to reduce your risk or prevent the disease entirely.

The same can be said for a range of conditions including heart disease, stroke and some cancers.

New technology and medical advances that make genetic testing easier and more accessible have the potential to change the healthcare landscape. But genetic testing is still a developing field, and researchers are learning more every day.

Before we can understand what genetic testing is, we need to talk about DNA, which stands for deoxyribonucleic acid, says Associate Professor Melody Menezes, Clinical Director at Victorian Clinical Genetics Services (VCGS).

"Our genes are made up of DNA, and DNA are the instructions that tell our body how to grow and develop."

"We receive half of our DNA from each of our biological parents," she says. "When people say that they're having genetic testing, what we're doing is testing the DNA."

While 99.9% of your genes are the same as every other human, it's the remaining 0.1% that makes you unique.

"We all have variations in our DNA, and that's what makes us individuals," says Melody. "It makes some of us have blue eyes versus brown eyes, or some of us be able to curl our tongue versus other people who can't."

While variations in DNA are normal, not all differences are helpful.

Genetic testing looks for variations in our DNA that might make us more susceptible to certain genetic conditions.

"Genetic information can be relevant at different times in our lives. For example, for those planning a pregnancy, genetic testing can assess the chance a couple may have a child with a genetic condition such as cystic fibrosis, spinal muscular atrophy or fragile X syndrome."

"In adults, genetic tests can indicate an increased risk of cancer, heart disease or other health risks such as a predisposition to high cholesterol."

Genetic testing alone can't prevent or cure any condition or disease. What it can do however, is provide insights and information about our current and future health.

"If a genetic test indicates a higher risk for cardiovascular disease for example, a person might choose not to smoke and eat less red meat," says Melody.

Genetic testing might also lead to earlier detection of a disease, meaning quicker access to treatment and potentially better outcomes.

"If a genetic risk factor for breast cancer is discovered, that person could choose to have more regular screening. If cancer does then develop, it is caught and treated at an early stage, which we know is important for long term health outcomes," says Melody.

You might be surprised to know that most genetic tests are simple, quick and painless.

"A blood test is the standard way to do genetic testing," says Melody. "Saliva tests, done with a cheek swab, are also becoming more accessible, meaning that while you need a referral from your healthcare provider, you can even collect the sample at home."

One of the most exciting parts of genetic testing is what might come next.

"It's currently uncommon for healthy adults to test for genetic conditions, whereas in reproductive and newborn screening genetic testing is very common. Adults typically only access genetic testing if there is a family history or the presence of a current condition, such as cancer," says Melody.

"Preventive genetic screening for healthy adults could provide meaningful, helpful information on some genetic conditions, and help people get care and treatment that could detect health conditions early or slow the progression of some conditions."

With technology improving and costs coming down, genetic testing is becoming more common, but it still isn't readily available as a first step in healthcare.

If you're interested in getting genetic testing the first step is to discuss it with your GP.

"Your GP will know your family history and may also be able to provide more routine blood tests to assess the risk for certain conditions. They may also be able to refer you for genetic testing if it's appropriate."

While there are private providers who offer genetic testing, Melody stresses the importance of finding a reputable company which adheres to Australian health guidelines, laws and regulations.

She also emphasises the importance of your healthcare team in guiding genetic testing to ensure it provides you with relevant and actionable insights into your health.

Although it's still a developing field, genetic testing has the potential to transform the future of health and delver truly personalised and preventive care.

Victorian Clinical Genetics Services (VCGS) is an Australian not-for-profit, with a focus on providing fast, accurate and personalised genetic testing services.