Cancer of the colon and rectum is one of the deadliest forms of cancer, and has in recent years affected growing numbers of young people. In the largest registry study to date, researchers at Karolinska Institutet and Harvard University in the USA demonstrate a possible connection between colorectal polyps in close relatives and the risk of developing colorectal cancer. The study, which is published in the British Medical Journal, is of potential consequence for different countries’ screening procedures.