Researchers at the University of Exeter are urging caution over the rapid expansion of newborn genome screening, warning that current evidence still leaves important questions unanswered about overdiagnosis and the accuracy of risk estimates in the general population.
The team’s latest work, funded by the Medical Research Council and the NIHR Exeter Biomedical Research Centre, is being presented at the European Human Genetics Conference on June 16, 2026. It draws on large population datasets, including nearly a million volunteers in UK Biobank and All of Us, to examine whether genetic variants linked to disease in high-risk groups carry the same level of risk when tested in newborn screening programmes.
Why researchers say the evidence needs to be stronger
The researchers say many genetic studies have historically been carried out in people who already have a condition, or in families already known to be at higher risk. That can make a variant appear more predictive than it really is in the general population, where newborn screening would be applied.
In their analysis, the Exeter team focused on more than 50 genes across 15 diseases that are included in large-scale newborn genome screening trials. They found that in most cases there was still a link between the variants and disease, but that the relationship was weaker than previous research suggested. The team also reported that the biggest risk of overdiagnosis appeared when disease risk was tied to the loss of just one of two copies of a gene, although the picture varied by condition.
Dr Leigh Jackson of the University of Exeter Medical School said the actual risk is often lower when evidence from the general population is used rather than from people already known to be at high risk. Professor Caroline Wright added that the UK is leading the way on newborn genome screening, but that the programme needs the best possible evidence to ensure it is done correctly.
Implications for families and the NHS
The researchers argue that getting these risk estimates right matters because a screening result can have a major impact on families. Being told that a baby is at high risk of developing disease can create significant anxiety and may lead to further testing and follow-up based on risk estimates that are not fully reliable.
The warning comes as newborn genome screening pilot studies are increasingly being rolled out in countries including the UK, with programmes aiming to sequence a baby’s entire genetic code and look for hundreds of potentially treatable conditions. The Exeter team says further studies are needed before such screening is expanded more widely, especially as policy makers weigh the potential benefits against the risk of unnecessary diagnosis.
As the UK continues to explore how genome screening could be used in early life, the Exeter findings suggest caution is warranted: the promise of earlier detection is real, but so is the possibility of overdiagnosis if the underlying evidence is not robust enough. Read the source article
