Knowing where you come from can tell you a lot about where you’re going

Our genes endow us with everything from our curly hair to our high cholesterol and predisposition to heart disease. But while curly hair is on the whole unlikely to cause major distress, health conditions like high cholesterol and heart disease are bound to.

There are many products on the market to treat various diagnosed diseases but a prevention method that has been gaining popularity worldwide over the past 10 years is DNA testing. This type of testing, which entails having a mouth swab that is sent for analysis, essentially looks at the risks of developing a particular disorder, and can establish whether a person is genetically predisposed to certain conditions.

Dr Danny Meyersfeld, the CEO of Johannesburg-based genetic testing laboratory DNAlysis Biotechnology, says there has been huge growth in the uptake of these tests globally over the past few years. “While it is growing trend in SA, generally we are still quite far behind the rest of the world when it comes to the widespread adoption of the tests at clinics and hospitals.”

According to Dr Dhesan Moodley, a specialist doctor in functional and anti-ageing medicine who practises in Johannesburg, the tests look for genetic anomalies.

“These DNA tests emerged in the last five to 10 years. Specifically, it tests for single nucleotide polymorphisms and pattern anomalies in the genetic code. There are hundreds of such possible variations. These anomalies will indicate whether the patient is predisposed to certain illnesses,” Moodley says.

“This does not mean that the patient will definitely suffer from these illnesses, but may be more likely to get these illnesses if they neglect their health. Conversely, with the correct preventative interventions, these illnesses can be avoided. This is the benefit of knowing your DNA profile, as you can avoid these illnesses.”

Meyersfeld concurs: “The tests are not diagnostic, and not aimed at those who are ill. The average person can benefit by better understanding where their own personal health risks lie, and most importantly, what they can do to mitigate those risks.”

Whereas humans have mostly the same DNA structure, gene variations account for disruptions in normal functioning. “Most of us have some minor gene variations. Some people may have major variations and will be more prone to the respective illnesses,” Moodley says.

For example, he adds, a patient who has the COMT [catechol-O-methyltransferase] gene variation “will have more difficulty with detoxification of hormones and other substances in the body. These patients may be more prone to breast cancer, as an example. However, with a healthy diet lifestyle and prevention, the patient can avoid ever suffering from breast cancer.”

Gene variations are being found to contribute to mood disorders and mental illness conditions such as depression, schizophrenia and bipolar disorder. The same COMT gene is thought to be a causative factor in these disorders too.

A study, published in 2015 in PubMed, by Arqam Qayyum and others, titled “The role of the Catechol-o-methyltransferase (COMT) gene Val158Met in aggressive behaviour, a review of genetic studies”, sought to investigate the molecular and genetic underpinnings of aggressive behaviour.

The researchers found that COMT was “involved in catabolising catecholamines such as dopamine. These neurotransmitters appear to be involved in regulating mood which can contribute to aggression. Aggressive behaviour is often observed in mental illnesses such as schizophrenia, attention-deficit hyperactivity disorder, borderline personality disorder, among others”, they concluded. 

Traditional expressions like “the apple doesn’t fall far from the tree” confirm that people have long known that health conditions tend to repeat themselves across generations. But science has been able to name the benefactors, or in some cases culprits.

For instance, a gene that has been associated with the debilitating disease cystic fibrosis is called the “cystic fibrosis transmembrane conductance regulator” (CFTR). And, according to the US-based Alzheimer’s Association, research shows that those who have a parent or sibling with Alzheimer’s are more likely to develop the disease than those who do not have a first-degree relative with Alzheimer’s.

“Researchers have found several genes that increase the risk of Alzheimer's. APOE-e4 is the first risk gene identified and remains the gene with strongest impact on risk. Researchers estimate that between 40-65% of people diagnosed with Alzheimer's have the APOE-e4 gene,” the association says.

It makes sense then to know your genetic profile so that you can as far as possible adapt your lifestyle to preventing any hereditary disorders resulting from your genetic endowment.

“We all know that eating right, exercising right and supplementing right are some of the key ingredients required for optimal health. However, we also know that there isn’t always a one-size-fits-all solution,” says Meyersfeld.

According to Moodley, anyone who wants to know more about their genetic predisposition for ailments should do the DNA tests. However, though an individual can order a specific DNA test, the testing company will only send the results to a registered medical practitioner, such as a GP, psychiatrist, or dietitian.

“The patient will need to go to a medical doctor or healthcare profession who is well versed in DNA studies to interpret their results. The doctor will explain the implication and provide dietary, lifestyle changes and a medical script if required,” he says.

Meyersfeld says for people who do not have a practitioner, DNAlysis employs in-house accredited practitioners to assist with providing feedback. He adds that a personalised approach is more effective, as studies show that dietary intake and nutrition knowledge is greatly improved in individuals who have received personalised nutrition advice compared to generalised dietary advice.

Other benefits of a personalised approach for patients are that it decreases the length of treatment time, minimises a trial-and-error approach in finding an effective drug therapy, limits the effects of disease through early detection, minimises side effects, and is therefore a cost saving.

Once the preserve of functional medicine — a treatment model that seeks a more individual approach to health by identifying the root causes of disease and using holistic treatment methods — DNA testing is also used by allopathic doctors.

Meyersfeld says: “The types of test we offer are integral to functional medicine, but they have long been a part of many mainstream/orthodox medical practices. For example, our Medcheck test, looking at responsiveness to prescription medications, is used almost exclusively by GPs and psychiatrists; but often they will order additional tests alongside that particular one. More and more, mainstream doctors are attending our training workshops and seeing the value of these types of tests in prevention of disease.”

One such is the DNA risk HLA-related autoimmunity test, which provides a diagnostic insight into patients already suffering from an autoimmune disorder, or who are identified as at risk due to a family history of disease and exposure to environmental risk factors, the company says. Some of the diseases the test covers include alopecia, Ankylosing spondylitis; coeliac disease; Graves’ disease; Hashimoto thyroiditis; multiple sclerosis; rheumatoid arthritis; vitiligo and lupus.

The DNAMind test, on the other hand, picks up predispositions to depression and addiction, among others. The Geneway company, also SA-based, says its Genewell product tests for genetic variants involved in physiological processes that are linked to an increased risk for certain lifestyle diseases, including bone health, caffeine metabolism, cancer risk, cholesterol and lipid metabolism, circadian rhythms (sleep disorders), dementia, carbohydrate sensitivity, dietary fat sensitivity, heart disease, inflammation, risk for diabetes, and lactose sensitivity.

In addition, it offers help with the complex condition of obesity. “Studies show that up to 70% of your risk for being overweight is determined by your genes,” says Geneway. “Your DNA also provides information about your feeding behaviours, natural appetite control, the fat-burning process, your genetic need for physical exercise to maintain a healthy body weight, and your sensitivity to dietary fat and carbohydrates.”

For people who are interested in keeping up their fitness, there are tests that can help you optimise your training and athletic potential by recommending your preferred fuel and energy source during exercise, response to caffeine, risk for inflammation, ability to deal with oxidative stress, muscle and bone composition, endurance and power potential, and susceptibility to injury and recovery time.

For anyone wanting to embark on having their genetic test done, Meyersfeld recommends starting with the DNA Core offering. He says this test suits “anyone looking for personalised insights into the core components of your health, including weight management, exercise strategies, diet and lifestyle interventions and nutraceutical supplements”.

In this way you can ensure you are eating the right food and taking the supplements that your body actually needs.

When many of us suspect that we are spending too much buying the wrong supplements, and that much of it ends up in our urine anyway, knowing we can get accurately tested is reassuring. And a saving on our stretched pockets.