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The Fertility Show


The 23andMe experience - a lot of knowledge is of little help?

23 February 2015

By Alison Lashwood

The British Society for Genetic Medicine

Appeared in BioNews 791

The 23andMe test and other similar direct-to-consumer (DTC) genetic tests are likely here to stay. Those in favour see them as a way of engaging the public with science and making it fun, but there are problematic aspects, too. The issue of interpretation of the results is perhaps of greatest concern.

In BioNews 788, Professor Joyce Harper highlights some of the issues that the general public need to be aware of should they undertake such testing.

One would expect a professor of human genetics to come quickly to an in-depth understanding of the test and results and be able to deploy her ability to interpret findings and contextualise them. But what Professor Harper highlights is that even with an elite level of genetics knowledge she was left with unanswered, potentially anxiety-causing, questions and no professional support to rely on post-test.

And while Professor Harper understood the limitations of the mutation testing, it is unlikely that the majority of 23andMe's customers would do so with no access to advice regarding interpretation of results or what they should do after the test. As a result some may be falsely reassured by the absence of a specific mutation or overly anxious about a genetic trait which may be insignificant.

In addition, Professor Harper understood the potential impact of accessing the 'locked' results for Alzheimer's and Parkinson's disease risk and for BRCA1 and 2 mutations. Alzheimer's and Parkinson's are both serious, late-onset conditions with no preventative treatment. Such knowledge in the hands of those unprepared for a high-risk result may have a significant practical (insurance/ employment), emotional and social impact.

Some may argue that DTC tests are no different to buying a blood pressure monitor, for example. There is similar potential to discover an unexpected reading and action may be required as a result. However a blood pressure monitor gives read-outs that are easier to interpret with clear parameters for normal/ abnormal outcome. Associated follow-up is straightforward, logically progressing to a GP appointment and possible onward referral to cardiology.

Such clarity, known parameters and follow-up are not true for 23andMe results. Firstly, there is a temptation to think a genetic code read-out is clear-cut but this is a misconception (for now at least). Also we do not know when the predicted ill-health might show itself, if it shows itself at all. Secondly, Professor Harper had an increased risk of deep vein thrombosis (DVT) yet received no direction as to how much higher than average the risk would have to be before taking different action from normal. Thirdly, there is no clear route for consumers to know what to do with the information.

Professor Harper sets out the scope of the 23andMe test and its limitations and says that Next Generation Sequencing would be the preferred test for picking out a mutation linked to a genetic disorder. This is true in a proper clinical setting, but we need to remember why people will take the 23andMe test. The majority are likely to be healthy individuals who see this as interesting and engaging and may want answers to their ancestry rather than their risk for future disease. There is confusion between a 'fun' read-out (how Neanderthal am I?) and health result (the chance of developing DVT). Those who are hunting for the genetic basis of a family disorder will be in a minority, but are perhaps of greatest concern.

People in the UK who have concerns about a family history of disease or potential risk of genetic disorder can freely access advice and support from their GP, from where they may be referred on to their local NHS clinical genetics service.

There they will be fully assessed and offered appropriate genetic testing, which will be interpreted by qualified professionals. Advice in relation to the limitations of testing, follow-on health care, and the implications of results for themselves and other family members will be given.

DTC tests may be here to stay, but as they gain a foothold, professionals should highlight the uncertainties, limitations of and alternatives to such testing to potential customers.



14 December 2015 - by Andelka M. Phillips 
There is now a huge range of direct-to-consumer genetic tests on the market, but the public ought to be wary of what exactly they are agreeing to when they sign up for these services...
17 August 2015 - by James Brooks 
23andMe, the biomedical wing of the industrial personal-data complex, has produced a board book for toddlers. The End Times draw near...
13 July 2015 - by Ceri Durham 
The American Society of Human Genetics (ASHG) has cautioned against genome-wide genetic testing unless clinically indicated, especially for children...
08 June 2015 - by Matthew Thomas 
'Genetics is messy and history is foggy. We are a species that is mobile and horny.' That is how Adam Rutherford quite accurately sums up the quest for understanding the human story in his documentary...
27 April 2015 - by Dr Indrayani Ghangrekar 
A US company has announced a low-cost genetic test for breast cancer...

02 February 2015 - by Dr Joyce Harper 
Partially out of curiosity and partially as an assignment for Radio 4's PM show, I was one of the first to 'get to know me', as their company slogan goes, and have my genome analysed by 23andMe...
15 December 2014 - by Dr Jess Buxton 
This discussion around the role of commerce in genetics and fertility treatment coincided with the launch of 23andMe's controversial personal genome service in the UK. Issues around health interventions following personal genetic testing were the focus of the second session at PET's conference, which asked: 'Whose genes are they anyway?'...
08 December 2014 - by Arit Udoh 
US-based genetic testing company 23andMe has launched its controversial 'personal genome service' in the UK...
12 December 2013 - by Dr Ruth Stirton 
23andMe and UK Biobank are both large genetic databases: big enough to engage in serious population genetic research. But 23andMe has not undergone any ethical approval processes - think what they could do if they sold their database...

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