Genomics in Primary Care

Bringing whole genome sequencing to primary care

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We explore how first-contact care and genomic testing could align, and the pivotal part this combination could play in the future

Results from a two-year pilot study have shown that primary care could play a major role in delivering whole genome sequencing (WGS), affecting how we treat disease.

The study, which took place in the UK from 2020-22, recruited healthy people to provide blood samples to a GP practice, which would then be used for WGS.

The WGS test looked for clinically actionable genomic variants that could increase the risk of health conditions, including cancer and cardiovascular disease.

The 90S study

The study was a collaboration between the Institute of Cancer Research, The Royal Marsden NHS Foundation Trust and a private GP practice, all in London. It aimed to discover whether screening using WGS could have a positive impact on health outcomes, and how willing people are to take part in this type of testing.

“Our study is the first to assess whether WGS can be delivered by GPs and demonstrates that it is feasible, provides important genetic information, and is likely to benefit patients by making preventative measures or counselling available to them,” said study leader and consultant in clinical oncology and oncogenetics at The Royal Marsden NHS Foundation Trust, Professor Ros Eeles.

Starting in 2019, the study recruited 102 healthy participants from the GP practice, some of whom had family histories of cancer or cardiovascular disease. Blood samples were taken in the primary care setting to be sent for WGS. The genome sequences were screened for over 500 separate genetic variants known to have effects on health – including variants linked to cancer, cardiovascular disease and response to medications.

Specifically, the screening was for ‘actionable’ variants – those changes where interventions such as lifestyle changes, screening programmes or targeted treatments can affect health outcomes. It did not report on risk associated with conditions where there are no current ways to affect outcomes.

First findings

Initial results from the study were presented at the 2022 Annual Meeting of the American Society of Clinical Oncology.

Of the 102 participants:

  • 26 were found to have potentially actionable genomic variants linked to conditions such as cancer or heart disease;
  • 38 had genetic changes that could affect their response to specific medicines; and
  • 61 were carriers of one or more recessive genes that did not impact their health but could be passed down to children, whose health could be affected if they inherit the same variant from their other parent.

“Our findings suggest that integrating WGS into primary care could change the way most patients and their families are managed by their GPs – either by detecting genetic variants that will affect a patient’s own health, or by highlighting their risk of passing on a genetic alteration which is important for future family planning,” said Professor Eeles.

Implications for care

Part of the rationale behind the study was to find out if integrating WGS in primary care settings is feasible.

On the future for this line of research, Professor Eeles said: “Next, we want to start looking into how to best implement genomic screening as part of family practice within the NHS – seeking ways to simplify and improve processes and make it suitable for large-volume NHS screening.”

Next steps also include evaluating whether patients who have been identified as having an actionable variant decide to take up screening or lifestyle interventions and, if so, whether this results in improved health outcomes. This also needs to be balanced against the risk of overdiagnosis – that is, detecting variants in people that do not end up causing disease.

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Please note: This article is for informational or educational purposes, and does not substitute professional medical advice.