Genome-wide association studies in colorectal cancer

© 2013 Springer Science+Business Media New York. All rights are reserved. The genome-wide association study (GWAS) generally involves the molecular and statistical analysis of thousands of individuals with a disease and similar numbers of unaffected or population controls. In short, a search is made for polymorphic alleles that occur more or less often in cases compared with controls, using stringent thresholds of statistical significance. GWAS have principally aimed to identify disease risk alleles that are common in the general population and that have modest effects on susceptibility. Over 20 common polymorphisms that influence bowel cancer risk have been identified by GWAS. Many of these polymorphisms act in the bone morphogenetic protein (BMP) signaling pathway, providing unexpected and important insights that could potentially be used to prevent adenomas and carcinoma of the colorectum, either using novel molecular agents or by stratifying the population for tailored screening by colonoscopy, sigmoidoscopy or fecal occult blood testing.