Key takeaways
- More and more people are using home genetic tests to explore their ancestry, and sometimes their genetic health
- Because the type of testing that is done doesn’t check the whole gene, at-home kits may miss faults that are in a different place
- Results from at-home kits arrive by email and support to analyse and understand them isn’t always offered
- If you’re worried about a family history of cancer, talking to your GP first will help to make sure you get the right help
Genetic testing at home (or direct-to-consumer genetic testing) is becoming more popular and many people will use these tests to look at anything from their ancestry to inherited talents. Some companies also offer health test reports to look for known gene variants linked to various health conditions. A common example of this type of screening is for the breast and ovarian cancer genes, BRCA1/BRCA2. Inheriting faults in these genes may lead to a greater chance of developing the disease, and at a younger age, because the genes can’t repair the damaged cells in the usual way. In this guide, Perci’s Lead Cancer Nurse Specialist Rachel Rawson, and Consultant Genetic Counsellor Dr Vishakha Tripathi, look at the advantages and disadvantages of this type of screening.
How does at-home genetic testing work?
Rachel Rawson, Lead Cancer Nurse Specialist
Most direct-to-consumer genetic tests are saliva based. The kit is sent with instructions and equipment for collecting a sample. This is then posted back to the company for analysis.
The results from an at-home test will be sent by email and, although there is some explanation about what the results mean, it can be difficult to understand their importance in relation to a person’s future health. Some testing companies offer an opportunity for further analysis or consultation, but others don’t.
How is at-home genetic testing different to testing by an accredited genetics lab?
The two main things that at-home genetic testing kits don’t do are test the whole gene and provide follow-up support.
Not testing the whole gene can mean that at-home testing kits miss faults that are in a different place. Using the example of breast and ovarian cancer, at-home kits only check for a limited number of faults on parts of the gene. In comparison, an accredited genetics lab would look for abnormalities in the whole gene, so nothing is missed. Checking the whole gene can help to predict cancer risk, which can help with future management and risk reduction. Trained genetics clinicians can provide guidance around types of tests, their uses and information about different labs.
More generally, some at-home kits screen for a multitude of health conditions. If your aim is to find out specifically about cancer risk, you might receive additional findings with little or no support to make sense of them. This can be very worrying. Sometimes only part of the test results are available on the report and some companies require additional payment for more complete information.
What to ask yourself before ordering an at-home kit
Dr Vishakha Tripathi, Consultant genetic counsellor
I am seeing an increasing number of people who have done a direct-to-consumer genetic test at home. Having options is always a good thing, but equally, there are some key questions people need to ask the provider – and also themselves – before they do this kind of test. Questions like, ‘Why am I seeking this information?’, ‘Where is this going to lead?’ and ‘Is there someone who can support me around this?’
Genetic test results don’t always provide information that can be used to change healthcare or disease management, so it’s important to ask questions about their use in the context of a condition someone might be worried about. If a person has a family history of a disease, or more general health anxiety, I would question whether an at-home test is going to help alleviate that.
As a consumer I would also have questions about the quality of the test and what happens to your sample. Who has access to your DNA and for how long? Do you have any legal rights over your DNA and your results? It’s important to understand all the implications of the test, before you make a decision to do it.
Having options is always a good thing, but equally, there are some key questions people need to ask the provider – and also themselves – before they do this kind of test.
Dr Vishakha Tripathi, Consultant genetic counsellor
What should you do if you are worried about the results of an at-home kit?
It’s natural to ask questions and to worry about your health, however, in most situations where an individual has completed an at-home genetic testing kit, the likelihood of anything being wrong is very small. Even if you have been alerted to a disease risk, it’s possible that won’t meet the current NHS threshold for being referred to a genetic counsellor.
Where people do meet referral criteria and are referred to a genetic counsellor, our first job is to carry out more complete testing in an NHS laboratory, to make sure that the result wasn’t a false positive or a false negative, and that the test is of sufficient quality. The information they’ve received might not be accurate or relevant, might not have not been interpreted correctly or at all. My job is to go down the correct clinical pathway with the person in front of me.
What would we recommend at Perci health?
If you are worried about your family history of cancer there are really clear guidelines that your GP will follow when they assess your family history. They will, where necessary, refer you to a family history clinic or a genetic specialist, where further checks can be made, and genetic testing carried out if appropriate.
This pathway will allow you to ask questions and have a full explanation at each step of the way, helping you to fully understand your family history of cancer and your own risk. It is really important to be supported in this way by a specialist team.
Rachel Rawson, Lead Cancer Nurse Specialist
If there isn’t a huge urgency – which there usually isn’t when ordering a direct-to-consumer test – my advice would be to pause before entering your credit card details and think about talking to your GP. They will almost always have come across other people in the same boat.
Having that clinical conversation can help inform what you choose and why you choose it. It can help you to make an informed choice and get the answers you’re really looking for. You can always choose to book a conversation with a genetic counsellor privately to reassure you and help you take the next appropriate step.
Dr Vishakha Tripathi, Consultant genetic counsellor
It can be tempting to explore our genetic health using at-home testing kits but difficult to understand the results and their implications for our long-term health without expert support. Our cancer nurse specialists have experience in discussing risk and suggesting appropriate support pathways. If you’re worried about a family history of cancer, they’re a great place to start.
While we have ensured that every article is medically reviewed and approved, information presented here is not intended to be a substitute for professional medical advice, diagnosis, or treatment. If you have any questions or concerns, please talk to one of our healthcare professionals or your primary healthcare team.
References
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‘The rise and fall and rise again of 23andMe’, nature.com, Oct 2017, https://www.nature.com/articles/550174a
Aviad E. Raz et al, ‘Transparency, consent and trust in the use of customers’ data by an online genetic testing company: an Exploratory survey among 23andMe users’, Taylor & Francis Online, May 2020, https://www.tandfonline.com/doi/full/10.1080/14636778.2020.1755636
‘Do at-home genetic tests work?’, mdanderson.org, Jan 2021, https://www.mdanderson.org/cancerwise/do-at-home-genetic-tests-work-and-predict-cancer-risk
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‘23andMe Review | 5 Things You Should Know Before Buying’, Genome Link Blog, Feb 2023, https://blog.genomelink.io/posts/23andme-review-by-experts