Alcohol consumption is known to raise the risk of certain cancers, but exactly how alcohol causes cells to stagger toward malignant fates is often unclear. To find ways of keeping cells on the straight and narrow, scientists based at MRC Laboratory of Molecular Biology, Cambridge, used mice to show how alcohol exposure leads to permanent genetic damage. In particular, the scientists found that acetaldehyde, an endogenous and alcohol-derived metabolite, can break and damage DNA within blood stem cells.

Although alcohol isn’t thought to cause blood cancers, blood stem cells offer a valuable way for scientists to investigate what’s happening to the DNA inside. For example, by showing how alcohol consumption can lead to rearranged chromosomes and permanently altered DNA sequences within blood stem cells, the MRC scientists uncovered mechanisms that could be relevant in other kinds of stem cells, including stem cells in tissues where cancer is …