Experts at Leicester University believe cholesterol medications could slow the growth of deadly aortic aneurysms, which kill 2,200 Brits each year.
There is currently no treatment for the illness, which causes the main artery out of the heart to inflate like a balloon and burst.
Professor Matt Bown said: “An effective treatment would be a huge breakthrough but has so far proved elusive.
“Despite it being relatively common, the only option we can offer patients is regular monitoring potentially followed by surgery if their aneurysm becomes too large.
“We’re hopeful that our findings can provide the foundation to propel us towards the first drug treatment for abdominal aortic aneurysm.”
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The aorta is the biggest blood vessel in the body and pumps blood out of the heart to the brain and rest of the body.
It is normally about 2cm thick but an aneurysm can cause it to swell to up to 5.5cm, putting it at risk of bursting and bleeding out.
Over-65s are most at risk and fatty build-up in the arteries, high blood pressure, high cholesterol and being overweight increase the danger.
Prof Bown scanned the DNA of 39,000 people with an aneurysm and found a close link to a gene called PCSK9.
When they blocked this gene in laboratory mice, their aneurysms grew slower.
There are already drugs to block the gene in humans, called PCSK9 inhibitors, and they are used to reduce high cholesterol.
Researchers are now planning trials to see if they can also slow or shrink aneurysms.
Professor James Leiper, of the British Heart Foundation which funded the study, said: “The consequences of an abdominal aortic aneurysm (AAA) bursting are catastrophic.
“More often than not, this will cost a patient their life.
“These promising results offer hope to thousands of AAA patients that their long wait for a treatment may soon be over.”