Hiding in the part everyone throws away: 18 new bacteria found in old cancer data

When scientists read a tumour's DNA, they usually keep the human parts and throw the rest away. A team at the University of East Anglia in Norwich wondered what was in the bin. Sifting 2,176 existing datasets — 247 samples from 194 patients — they rebuilt the genomes of 18 bacterial species nobody had ever described, most of them mouth bacteria, including new kinds of Porphyromonas and Treponema. Earlier work had linked a group of such bacteria to faster-progressing prostate cancer, but without genomes there was no way to measure or study them properly. Now there is: 'Every one of these organisms was hiding in plain sight,' says first author Abraham Gihawi. The team is careful — this does not show the bacteria cause cancer — but it gives researchers the tools to finally ask that question properly, and one day possibly to spot men at higher risk sooner.

SDG 3 · Good health and well-being — Mechanism: tech innovation