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Will Genomics Motivate Healthy Behaviours?

Credit: Marek/adobe

Credit: Marek/adobe

By Amelia Smit & Anne Cust

Will communicating the genetic risks of disease necessarily motivate people to make healthier behaviour choices?

Healthy lifestyle behaviours, such as eating plenty of fruits and vegetables, doing physical activity, maintaining a healthy weight, using sunscreen, refraining from smoking and heavy drinking, and adhering to screening programs, are widely acknowledged as ways to prevent and reduce the risk of common health conditions and diseases such as cancer and heart disease. Despite this awareness, the number of people suffering from preventable diseases continues to increase in populations across the world.

Innovative strategies are needed to motivate healthy behaviours in the general population. Can genomics help fill this gap?

Over the past 10 years, there has been an explosion of knowledge about genomic risk factors for common diseases. This knowledge presents a promising opportunity to see whether or not genomic risk information could be used to improve population health through the prevention and early detection of diseases.

What Is Genomic Risk Information?

Genomic risk information is disease risk information based on genomics, taking into account common variation in several or many genes to estimate a person’s chances of developing certain health conditions and diseases. Although each variant is itself usually associated with only a small increase in risk, together they can have a large influence on risk and on the population’s disease burden because they act in combination and are common in the population.

A person’s likelihood of a disease can be estimated and classified into a low, average or high-risk category based on their genomic variation. For example, you could find out whether you have a low, average or high risk of developing different kinds of cancer based on your genomic information. Knowing your risk of diseases means that you could make changes in your behaviour (such as diet or exercise) to lower your overall risk and adjust the frequency of your medical checks such as screening tests.

But will genomic risk information motivate healthy behaviours to influence the future risk of disease?

Expectations of Genomic Risk Information

It is well known that changing peoples’ lifestyle behaviour is difficult. What we already know about behaviours tells us that the highly personalised nature of genomic information about disease risk may be a more effective way of encouraging behaviour change than standard approaches. For example, genomic risk information might motivate healthy behaviours through family networks by allowing families to understand their behaviours and disease risk as a shared issue that they can deal with together. In this way, reducing unhealthy behaviours could be encouraged not only for the individual but also for their families.

It’s anticipated that genomic risk information might improve health by motivating healthy lifestyle changes that reduce the risk of developing disease, screening for early detection of disease, and personalising treatments and medications. There are expectations that general practitioners would be involved in delivering genomic risk information to the public, but exactly how genomic risk information could be delivered is still up for discussion.

Research on Behaviour Change

The research on this topic is still at an early stage. A recent scientific review published in the British Medical Journal ( summarised the results of 18 studies that examined the impact of genomic or genetic risk information on behaviour change. Most of the studies examined smoking cessation, diet and physical activity behaviours. Although there were some indications of benefits, particularly for diet and sun protection behaviours, overall there was no strong evidence that communicating the genetic risks of disease motivates people to make healthier behaviour choices.

However, there is still much ground to cover before we can confidently make conclusions about the impact of genomic risk information on behaviours. Most of the studies done so far have been too small, done in a way that makes them vulnerable to bias, or conducted among groups defined by specific characteristics such as those with a family history or at a particular workplace. So, it is difficult to know how genomic risk information will impact behaviours in the broader population, and we need high-quality studies to investigate this impact.

In addition, most of the studies conducted so far have not included all relevant gene variants for a particular disease, so they have not used all the relevant genomic information available. The potential for genomics-based disease risk information to motivate behaviour change will depend on how well the genomic variants predict disease and to what extent modifying behaviours can reduce disease risk. Since studies have not included all the relevant genomic information, it is less likely that people will be motivated to change their behaviours.

Ideally, genomic risk information should accurately predict the risk of future disease, particularly so that those classified as high risk can increase their risk-reducing behaviours. For example, someone whose genomic risk places them at high risk of skin cancer may decide to wear sunscreen or may start regular skin checks. These behaviours would reduce their risk of future skin cancers and increase their chances of finding any skin cancers early on.

The types of behaviours and the extent to which they are modifiable on an individual level are also likely to influence behavioural responses. For example, eating plenty of fruit and vegetables is a healthy behaviour that reduces a person’s risk of some cancers. But if you don’t have easy access to fresh fruit and vegetables then it would be difficult to change this behaviour. As risk-reducing behaviours differ according to health conditions and diseases, targeted research specific to different conditions and diseases is required to understand the impact of genomics-based disease risk information.

Changing a person’s behaviour may require more than just giving them genomic risk information about diseases. Behaviours are complex, develop over time and are influenced by a number of factors such as knowledge, family and friends, education, personal beliefs and skills and the environment. Communicating genomic risk information probably needs to be coupled with effective strategies that influence these other factors.

What Else Do We Need to Investigate?

In order to understand the potential of genomic risk information to motivate healthy behaviours, we need to ensure that recipients understand both the risks and benefits of genomic testing, and are able to correctly interpret the risk information. Acceptable methods of communicating and delivering genomic information must be established, particularly as comprehension and interpretation are impacted by the context of delivery. Support strategies for individual decision-making about testing and receiving genomic risk information are also required so that questions or concerns can be addressed and emotional support provided. Appropriate support strategies might be the local doctor, a genetic counsellor or other trained health professional or educator.

Whether or not disease risk information based on genomics will motivate healthy behaviours also depends in part on the capacity and ability of individuals to make lifestyle changes. The personal skills and confidence required to change behaviours should also be taken into consideration.

For example, if you don’t know how to lose weight, or you have tried unsuccessfully in the past, then it may be difficult for you to take steps to lose weight in the future. To make this change, you probably need assistance from health professionals and additional support from family and friends. The impact of genomic risk information might be strengthened if accompanied by skills development through education about behavioural risk factors and practical ways to improve risk-reducing habits.

There is also a concern that genomic risk information could have negative psychological impacts, although this has not been found by any of the studies conducted to date. It’s important that studies consider the broader social and ethical considerations of receiving genomic risk information in order to understand behavioural responses and to prepare for and minimise any potential adverse consequences.

Ethical considerations include how best to inform people when asking them to make a decision about receiving genomic risk information, and the impact on feelings such as “genetic fatalism” – the feeling that genes determine health outcomes regardless of individual action. For example, some people may not change their behaviour if they believe that their actions will not influence their risk of disease.

Social considerations include the potential broader impact of a person’s genomic risk information on their family and friends if that person chooses to share their risk information.

Privacy and insurance concerns also need to be addressed.

A Need for Comprehensive Research

Communicating disease risk information based on genomics is a novel approach to encouraging risk-reducing behaviours. Preliminary research on this topic is not yet adequate to draw firm conclusions about whether genomic risk information could be used to motivate healthy behaviours, as well as the potential psychological, social, ethical and economic impacts.

More rigorous and comprehensive research studies are required to address these important questions so that we can make more informed decisions about how genomics might be incorporated into public health strategies.

Amelia Smit is a Research Study Coordinator with the Cancer Epidemiology and Prevention Research group at The University of Sydney’s School of Public Health, where A/Prof Anne Cust is NHMRC and Cancer Institute NSW Career Development Fellow.