Polygenic scores and risk

Genetics plays an important role in the development of disease, and genetic testing is often used to identify rare, heritable diseases where the presence of a single genetic variant is highly predictive of disease. However, common diseases – which account for most of the healthcare burden – are not caused by single, high impact genetic variants. Rather, the genetic element of risk usually arises from the effect of multiple genetic variants. These are much harder to identify and assess, making risk prediction harder.

One recent development is the polygenic score, a means of aggregating information from these multiple small-effect genetic variants to assess risk for a given disease. Polygenic scores combine information from multiple genetic variants into a single score that can be used to examine risk. Recent advances in this field have reignited interest in using genetic information in personalised prevention approaches for common conditions such as cancer and heart disease.

Our work in this area aims to keep pace with the rapidly developing science to produce timely and relevant policy intelligence and insights, and to support the delivery of real health benefits.

Disease risk assessment

The use of polygenic scores for common disease risk assessment is one important area of development. Our report, Polygenic scores, risk and cardiovascular disease examines the current evidence and readiness for clinical implementation of polygenic scores from the perspective of cardiovascular disease prevention. 

The challenge of clinical utility

There are differing opinions as to the value of genetic information in the form of polygenic scores and how these could be used in disease prevention. Much of this is due to differing views of clinical utility which can hinder uptake. We are working with stakeholders to bring together key concepts around clinical utility and test evaluation frameworks in order to better assess the potential utility of polygenic scores in healthcare.

Wider impacts of polygenic risk scores

Another element of our work is investigating potential ethical, psychological and societal impacts of using polygenic scores. How might knowledge of polygenic risk prompt changing prescribing practice by health professionals or behaviour change in patients? What additional support might be needed to generate and sustain these changes in behaviour (whether medical interventions or lifestyle changes) to reduce or manage risk, a crucial element of personalised prevention approaches?

If you would like to know more about this project, please contact Laura Blackburn.