While not a direct cause of cancer, the researchers suspected that over time this could lead to key anti-tumour genes being damaged that would normally prevent cancer from developing.

To test if this was the case the researchers knocked out an additional gene known as p53, which is known to be faulty or missing in more than half of all cancers.

They found that the second faulty gene tipped the cells over the edge, causing widespread DNA damage and greatly increasing the likelihood of cancer developing.

Dr Lesley Walker, director of cancer information at Cancer Research UK, said: "We've made great progress in developing drugs for hereditary breast cancer - particularly in targeting cancers caused by specific faulty genes through drugs like PARP inhibitors.

"It would be fantastic if these drugs could 'multi-task' and treat prostate cancer too.

"While we'll need to see the results from more patients before we know if this drug could be used in men with this type of prostate cancer, this discovery shows that it's an exciting possibility."

Source: Cancer Research UK