Genetic Testing: An Overview of Types, Providers & Considerations
“There’s no gene for the human spirit” -Gattaca 1997
The 1997 American science fiction film ‘Gattaca’, starring Uma Thurman and Ethan Hawke, tells the story of a future world where everyone’s life is determined by genetic engineering not education or experience. It’s a world where parents genetically design their offspring and the main character has to steal a genetic identity in order to progress in his career. At the time of its release, the film sparked philosophical and ethical debates about genetic engineering. Today, twenty years later, that world seems closer to reality than science fiction.
It’s this aspect of genetic science - the thought that we could be heading towards a future world of ‘designer babies’ - that puts many people off the idea of genetic testing. Yet it’s an area that’s fast-gaining momentum in the functional medicine world. Genetic testing offers tremendous scope for personalised healthcare, however if you’re thinking of getting tested or of using the tests in practice, it’s definitely worth doing your homework first as it’s a complex area.
To get you started, we’ve put together a very simple overview on functional genetic testing. We wanted to dispel some myths and give you a clear idea of what functional genetic testing is (and isn’t), why you might use the tests, the leading laboratories involved in genetic testing in the UK and some of the ethical and practical considerations you need to take into account too.
What is functional genetic testing?
To understand the basics of functional genetic testing you first need to get your head round a bit of the science behind it. Your body contains 50 trillion tiny cells and almost every one of them contains a complete set of instructions for making you, all cleverly bound up in your DNA.
To make new cells, an existing cell divides into two and first must make a copy of its DNA. Sometimes mistakes are made during the copying process and this leads to variations in the DNA sequence. These are officially known as single nucleotide polymorphisms or SNPs for short. Most mistakes or SNPs lead to no differences at all, however some can lead to variations in physical appearance or health such as your susceptibility to specific diseases, what you look like or how you will respond to certain drugs. SNPs can be passed onto offspring too, so it’s likely that you will have inherited some from your parents and that your kids will have inherited some of yours too.
There are many different SNPs, with new ones being discovered all the time, and we all have at least some. You can’t remove your SNPs but for many of them, there are steps you can take to influence whether or not they will affect your health.
As science advances to uncover more and more SNPs, so does research into how you can best match your environment to your genetic profile. Environmental factors such as diet and lifestyle have a huge impact on how your SNPs will ultimately affect your health and this is where functional genetic testing becomes an incredibly useful and exciting tool for personalised healthcare. There’s a common misconception that genetic testing will just deliver depressing information about future health problems that you can’t do anything about, yet the reality is very different. The actual purpose of these tests from a functional medicine perspective is to learn more about your own genetic profile so you can best match your diet and lifestyle to it. This can help you to improve your health now and reduce the risks of future problems that may be lying in wait.
There are many different tests looking at a wide variety of different SNPs.
Genova Diagnostics, one of the leading functional testing laboratories in the UK, offers a range of tests grouped under different profiles; for example, their EstroGenomic profile looks at a range of SNPs that may increase genetic susceptibility to health problems such as breast cancer, osteoporosis and heart disease. And their DetoxiGenomic Profile evaluates a range of SNPs associated with an increased risk of poor detoxification, especially when exposed to environmental toxins. This profile also identifies whether you’re at high risk of adverse drug reactions. Nutrigenomix, another laboratory that offers tests in the UK offers a genetic test that looks at how your body genetically responds to specific foods and nutrients. With this test you get a personalised nutrition assessment that enables you to ‘eat according to your genes’.
There’s even a new wave of genetic tests on the market to help you discover your family history, some even claim they can tell you whether you have direct links to Neanderthal man. Ancestry DNA offers a test which tells you about your ethnicity across 26 regions / ethnicities and identifies potential relatives through DNA matching to others who have also had the test done. Ancestry DNA say it is “a great starting point for more family history research, and it can also be a way to dig even deeper into the research you’ve already done”. It’s a fascinating area, however it’s important to remember that these particular tests don’t offer any health-related genetic information; rather they’re something you’d have done purely out of interest in finding out more about your ancestry.
This is just a snapshot of the vast amount of tests available. Practitioners may recommend just one or more tests, depending on patient needs. Testing can be expensive so it’s important to choose the profile that’s right for you and represents the best value for money in terms of what you will get out of it and how this could impact your health.
Why use genetic tests?
• Often provides missing puzzle pieces for patients with chronic, complex health problems who may be resistant to standard treatments. Genetic testing takes away the guesswork and can help guide practitioners towards highly effective treatment protocols. Results often increase patient compliance too.
• Identify whether you’re at higher risk for a variety of conditions and what you can do to reduce your risk
• Some tests identify medications that are likely to be effective, those that aren’t and whether you’re at high risk of adverse drug reactions.
• Unique RDAs for many vitamins and minerals, and personalised nutrient advice too
• Personalised dietary support for key biochemical pathways such as detoxification and methylation
• Identify limitations in conversion pathways for many nutrients
• Your susceptibility to oxidative damage (one of the key factors influencing chronic disease) and how you can provide unique support to counteract this
• Your tendencies towards neurotransmitter, hormonal and gut bacteria imbalances
• Dietary support for balancing inflammation
Who offers testing?
Here are the main laboratories offering genetic tests in the UK. Some laboratories offer tests directly to members of the public and others are only available through a qualified practitioner.
Practical and ethical considerations
• Sample collection - Genetic testing is one of the easiest in practical terms as most test kits simply require a saliva sample or mouth swab from you. Blood samples are not usually necessary.
• Data storage - Many people worry about the security of the processing and storage of their genetic material / information and this is where it pays to do your homework when choosing a lab. Reputable laboratories maintain strict procedures around data protection and anonymity. Samples are often labelled and registered against a barcode rather than a name and are usually destroyed after results have been processed. Every lab stores results differently, however 23andMe is unique in that it stores all data permanently in an extensive database and uses it for genetic research. Read the small print in the terms and conditions and make sure you understand fully and are happy with how the lab you have chosen will process and store your genetic information.
• Support - Some labs offer tests directly to members of the public and others will only sell tests through a qualified practitioner and this raises an interesting ethical debate. Personally, I would always recommend that any genetic testing only be done through a qualified practitioner who has the necessary training to recommend the most appropriate test (taking into account cost considerations too) – many of the leading laboratories offer comprehensive training to practitioners wanting to use their tests. Practitioners should also be able to interpret the results, advise on the most effective dietary and lifestyle modifications to match genetic profile and be able to provide psychological support to avoid / reduce test result-associated health anxieties.
Is genetic testing for you?
Whether or not you choose to see genes, they will always be there and will continue to play an important role in your health. For genetic testing to be of any value however, you must be ready and willing to make positive changes to your diet and lifestyle, so it’s important to be honest with yourself on whether you think you can do this, before embarking on any tests. By choosing to look at your genes, you have the opportunity to influence the ultimate outcome and more actively promote a healthy life. As a final thought on the subject, it’s worth remembering the famous Gattaca quote that reminds us ‘there is no gene for the human spirit’. Genetic testing is a useful tool, however it’s easy to get caught up in the current interest surrounding it and to overestimate its importance. We are all capable of achieving amazing things and far from deciding our fate; our genes represent only a part of our total potential.
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