Researchers at University Hospital Southampton (UHS) are launching a pioneering study to investigate the genetic factors that influence the development and rupture of brain aneurysms.

The world-first research could lay the groundwork for the UK’s first genetic screening programme for the condition – potentially transforming how the NHS identifies and manages patients at risk.

Known as ROAR-DNA, the study brings together researchers from UHS and the University of Southampton – led by Professor Diederik Bulters, consultant neurosurgeon at UHS.

It will analyse genetic data from 6,000 patients with unruptured brain aneurysms to identify markers that may predispose individuals to the condition.

A brain aneurysm is a bulge or ballooning in a blood vessel in the brain. Around two million adults in the UK are estimated to be living with one. Treatment is typically only recommended when the risk of rupture is high.

While most aneurysms remain stable, approximately one in every hundred will rupture – often without warning – causing a subarachnoid haemorrhage (SAH), a type of stroke that can be fatal or severely disabling.

Each year, an estimated 3,000 to 5,000 people in the UK experience a rupture, with around half of these cases proving fatal.

The multi-centre study aims to enhance the risk prediction models currently used by NHS neurovascular teams. Existing tools are limited and do not account for key factors such as sex and family history – despite evidence showing that aneurysms often run in families. Over 16% of patients have a parent or sibling who has also been affected.

Although the burden is significant, there is currently no genetic screening programme in place, and little is known about the genes that influence aneurysm growth and rupture.

Prof. Bulters said: "Brain aneurysms typically produce no symptoms but can burst without warning with catastrophic consequences.

“The reality is that the majority will never rupture, but we currently have no way of identifying the minority that will. We are making great strides in understanding clinical risk factors, but our ability to understand the genetics behind their development and rupture remains surprisingly limited.”

The study will run over four years and will work in tandem with the existing Risk of Aneurysm Rupture (ROAR) study which is already tracking over 20,000 patients across the NHS – making it the largest study of its kind in the world.

Prof. Bulters added: "ROAR-DNA is designed to offer a more complete picture of who is most vulnerable to aneurysms.

“It could pave the way for targeted NHS screening programmes that identify and monitor high-risk individuals before an aneurysm becomes life-threatening. This may open up new possibilities for therapeutic treatment to reduce the need for invasive surgery."

Rebecca Middleton, CEO of HBA Support, a project partner supporting patients and families affected by brain aneurysms, said: “This research is urgently needed. My family has been devastated by this condition and I was treated seven years ago for a growing brain aneurysm. I’m just one of thousands left wondering whether my family history puts other close relatives at risk.

“This study could save lives and heartache. For patients, this is not just about science – it’s about hope, reassurance and the possibility of preventing future tragedies."

This spring, ROAR reached its ambitious recruitment target of 20,000 patients. Initial results are expected later this year. Enhanced models emerging from these studies will provide clinicians and patients with clearer, evidence-based pathways for care.

The new study has received over £2 million in funding from the Medical Research Council. Recruitment for ROAR-DNA is set to begin this autumn. Patients across the UK can learn more at https://roarstudy.co.uk.

Hospital Trust leads world-first genetic research into brain aneurysms