Gene Variants Linked to Bowel Cancer

Four new genetic variants linked to colorectal cancer have been discovered by combining data from three major genome studies.

Pooling the data from these studies created the largest study of its kind, involving over 45,000 volunteers with and without bowel cancer, allowing previously undetected genetic sites to be pinpointed.

In a collaborative study, British scientists scoured the genomes of 3,334 bowel cancer patients and 4,628 people without the disease from across the UK, using DNA extracted from blood samples. Comparing the genomes of people with and without the disease allowed them to identify a total of seven different one-letter alterations in the genetic code (single nucleotide polymorphisms), where genes involved in the development of bowel cancer were most likely to be found.

To confirm their finding they then looked at an additional 18,095 bowel cancer patients and 20,197 people without bowel cancer. Four of the seven genetic sites were clearly associated with small but significantly raised risk of bowel cancer among the general population, bringing the total number identified to fourteen. The Cancer Research UK, (London, UK) funded the study and is behind all fourteen of the gene variants that have so far been linked to bowel cancer which have been identified as the result of ten years of investigations.

Richard Houlston, MD PhD, from the Institute of Cancer Research, (Sutton, UK) and senior author of the study, said, "Our study identifies four completely new genetic variants that can influence a person's risk of developing bowel cancer, suggesting that even more variants linked to bowel cancer are yet to be discovered.

Although each of these variants has only a small impact on a person's risk of developing the disease, there is now genuine hope that as more pieces of the jigsaw are discovered, identifying those who are at highest risk, helping to find better target measures to prevent the cancer, or detect it earlier maximizes the chance of treatment being successful. The study was published online October 24, 2010 in Nature Genetics.

Related Links:
Cancer Research UK
Institute of Cancer Research