Colorectal cancer
Inherited genetic factors play an important role in the etiology of colorectal cancer. Rare high-penetrance mutations account for a small proportion of diseases but their identification plays an important role in the clinical management of the high-risk families in which these mutations segregate. The results of most candidate gene association studies of colorectal cancer have not been replicated consistently. Many results can be considered false positives; others may represent very small effects, which will require replication in larger studies before firm conclusions can be reached. This chapter reviews recent, genome-wide association studies that have discovered many common, low-penetrance genetic variants associated with risk of colorectal cancer.