What if you could know about your genetic risk of lots of common, complex conditions, such as heart disease, cancer or diabetes? In this blog, Senior Research Fellow at King’s College London, Dr Saskia Sanderson, discusses the psychological and behavioural evidence around people’s understanding of polygenic risk scores and how they might respond if they were given this information.
Getting genetic risk information about ourselves is increasingly becoming a possibility with the development of polygenic risk scores.
Genetic testing for rare DNA variants that can have a large impact on disease risk has been around for a long time. Perhaps the best-known examples are variants in the BRCA1 and BRCA2 genes, which substantially increase the risk of breast and ovarian cancer.
But these relatively rare variants are only one part of the genetic story.
We also have millions of more common DNA variants across our genomes. Many may have no detectable effect on disease risk; others each have a very small effect. On their own, the impact of any one of these variants may be minuscule. But when scientists combine information across large numbers of variants — sometimes thousands or even millions — they can identify people whose genetic profiles are associated with higher or lower risks of particular diseases.
These combined measures are called polygenic risk scores, or PRSs. “Poly” means many, and “genic” relates to genes: in simple terms, the scores bring together information from many genetic variants.
From genetic prediction to healthcare
Polygenic risk scores are already being used in research studies around the world and are being considered for use in healthcare.
For some conditions, including coronary artery disease, polygenic risk can identify substantial differences in risk between individuals. This raises the possibility that polygenic risk scores could eventually be incorporated alongside established risk factors in clinical risk assessments.
But this raises another set of questions.
It isn’t enough to ask whether polygenic risk scores can predict disease risk, or whether they can be integrated into clinical risk assessments in clinically meaningful ways.
We also need to ask: what happens when we give this information to people?
Do people understand it? How does it make them feel? And does it change what they do?
These questions matter. If people don’t understand the information, that’s a problem. And if people respond to it in ways that could be harmful or unhelpful, that’s a problem too.
Five psychological and behavioural questions
These are some of the questions that Michael Inouye at the University of Cambridge and I explored in a paper published in Nature Human Behaviour in 2025.
We considered five arguments against integrating polygenic risk scores into clinical practice that relate specifically to psychological and behavioural concerns. We looked at the scientific evidence accumulated so far, alongside relevant behavioural theory, and considered how well each argument stands up to scrutiny.
1. Will people understand polygenic risk scores?
One concern is that patients and members of the public won’t understand polygenic risk scores well enough to give informed consent, participate meaningfully in discussions about their use or engage in shared decision-making.
The evidence in this area is still limited, but we don’t think this argument stands up to scrutiny.
Co-designed and co-developed educational resources can help patients, families and members of the public understand complex genomic information. We have seen this in other areas of genomics, including genome sequencing, and there is good reason to think the same can be done for polygenic risk scores.
The answer to complexity should therefore not simply be to withhold information. It should be to work with people to find better ways of explaining and communicating it.
2. Could lower-risk results lead to false reassurance?
This is a question I get asked a lot.
If somebody is told that they have a lower polygenic risk of a disease, could they become falsely reassured and conclude that it is safe to eat, drink or smoke whatever — and however much — they want?
Based on the evidence available so far, alongside behavioural theory, there is little evidence to support this concern.
It’s also interesting that this concern seems to arise particularly strongly around genetic information. We don’t tend to make the same assumption about someone receiving a favourable cholesterol or blood-pressure result, even though these are also only individual components of a person’s overall risk.
This is one example of what is sometimes described as genetic exceptionalism: treating genetic information as fundamentally different from other kinds of health information when the evidence may not justify doing so.
3. Will higher-risk results change what people do?
Another important question is whether receiving a higher-risk polygenic risk score actually changes behaviour.
One possibility is that learning about higher genetic risk might motivate people to make so-called ‘lifestyle’ behaviour changes — to eat differently, exercise more, stop smoking or make other changes to reduce their risk.
The evidence so far suggests that genetic risk information on its own does not reliably lead to so-called ‘lifestyle’ behaviour changes. But this is not unique to genetic information. Risk information more generally does not, on its own, reliably change complex and established health behaviours.
Human behaviour is influenced by many different factors. Information about risk can be important, but it is only one part of what shapes what people actually do.
This doesn’t mean that higher-risk results have no behavioural impact. Indeed, they can lead to important clinical behaviours.
For example, if incorporating a polygenic risk score moves someone across a clinically meaningful risk threshold, a healthcare professional might prescribe risk-reducing medication, and the patient may then take that medication. Other preventive or clinical actions may also follow.
So, when we ask whether polygenic risk scores change behaviour, we need to think broadly about what we mean by behaviour. The important question is not simply whether giving someone genetic risk information directly motivates them to change their ‘lifestyle’. It is how that information, as part of a wider risk assessment and care pathway, might contribute to behaviours and actions that ultimately improve health.
4. Could higher-risk results cause anxiety or distress?
A fourth concern is that telling somebody they have a higher genetic risk of disease could cause anxiety, depression or lasting psychological distress.
This is an important possibility to investigate rather than assume.
However, the wider evidence from genetic risk information, together with the emerging evidence on polygenic risk scores, does not currently support the idea that receiving higher-risk genetic information generally causes lasting psychological or emotional harm.
Individual responses will vary, and we need to continue studying them as polygenic risk scores move into more real-world settings. But the evidence available so far does not support psychological harm as a general reason for excluding polygenic risk scores from clinical practice.
5. What if healthcare professionals don’t understand them?
Finally, there is a legitimate concern about whether healthcare professionals currently have sufficient knowledge about genetics and polygenic risk scores — and, more broadly, about communicating and interpreting risk.
But if healthcare professionals don’t yet understand enough about a new technology or a new tool in the toolbox, the response should not be to exclude that tool.
Instead, we need to invest in co-designed education and support for healthcare professionals, including resources that can be used at the point of care.
That matters for healthcare professionals themselves, but also for patients and the public. Good shared decision-making requires both sides of the conversation to be supported in understanding what a risk estimate does — and does not — mean.
Where do we go from here?
Psychological and behavioural considerations should be central to thinking about how polygenic risk scores are introduced into healthcare.
We need to understand not only whether the scores predict disease, but whether people understand them; how they feel about receiving them; how healthcare professionals communicate them; and what happens afterwards.
And we need to approach all of these questions in an evidence-based and thoughtful way.
More research is clearly needed, particularly as we move from research studies towards more realistic evaluations of how polygenic risk scores might be integrated into healthcare.
But based on the evidence available so far, we concluded that the major psychological and behavioural arguments against using polygenic risk scores do not stand up to scrutiny.
That doesn’t mean we should introduce polygenic risk scores without careful evaluation. Quite the opposite. It means that as the science of polygenic risk advances, the psychological and behavioural science needs to advance alongside it.
Because ultimately, the question isn’t only whether we can calculate someone’s genetic risk, it’s also what happens when we tell them.
