Thousands of cases of bowel cancer in Britain each year are linked to a common bacteria found in the gut.
Scientists analysed tumour cells in the lab and concluded the toxin released by a strain of E.coli could be a factor in more than 2,000 UK diagnosis every year.
The toxin was found to case DNA damage to the cells lining the digestive tract.
This was also seen in bowel cancer tumours from British and Dutch patients in research published in the journal Nature.
Hans Clevers, of the Hubrecht Institute in the Netherlands, who led the study, said: “Things like tobacco or UV light are known to cause specific patterns of DNA damage, and these fingerprints can tell us a lot about past exposures that may have caused cancer to start.
“But this is the first time we’ve seen such a distinctive pattern of DNA damage in bowel cancer which has been caused by a bacterium that lives in our gut.”
It suggests such genetic errors that originate in the gut drive cancer growth and is the latest example of research showing the importance of bacteria living there.
The bacteria was linked to one in 20 cases of bowel cancer.
There are about 42,000 new bowel cancer cases in Britain every year and it is the second biggest cancer killer.
Leading nutritional therapist Sarah Brookes, of the Autoimmune Hub , said: “The health and balance of the gut microbiome is important in preventing many chronic illnesses.”
