Researchers identify certain gut bacteria that may be involved in causing bowel cancer

People who have a certain type of bacteria in their guts may be at greater risk of developing bowel cancer. The findings were presented by University of Bristol researcher, Dr Kaitlin Wade, at the 2019 NCRI Cancer Conference in Glasgow today [4 Nov]. While there is increasing evidence that the make-up of the gut microbiome plays a role in the human health and the body's susceptibility to disease including an association between the microbiome and bowel cancer, very few have provided convincing evidence for causality. The study is the first to use Mendelian randomisation to investigate the causal role played by bacteria in the development of bowel cancer. This scientific technique uses complex statistical analysis of data from large populations to provide evidence for cause and effect, rather than just the existence of an association. Dr Wade , from Bristol Medical School , explains: "In other words, it's really difficult to discern whether components of the gut microbiome can cause bowel cancer, whether the disease itself leads to variation in the gut microbiome or whether the association is due to some other factors that cause variation in both." The human gut microbiome is a community of microorganisms, bacteria in this case, that occur naturally in the body. Containing approximately three trillion bacteria, the microbiome aids digestion and provides protection against infections.