Rare Bowel Cancers / Posted 1 year ago
CORGI 2: A study to find genes that might increase or reduce the risk of bowel cancer
Colorectal cancer (CRC) remains an important cause of morbidity and mortality. Identifying those at higher risk is important in targeting preventive measures, such as screening colonoscopy, to those most likely to benefit. Much of the risk of CRC and its precursor lesions (mostly polyps) is genetic, but a great deal of the heritability of CRC remains unexplained. Some of the remaining genetic risk probably results from rare genes with large effects, some from uncommon genetic variants with moderate effects and some from common differences with modest or very modest effects. The sub-division between these categories is extremely difficult to predict in advance of successful searches for these genes.
The principal aim of this study is to identify additional susceptibility genes for CRC and cancers genetically related to CRC, such as endometrial cancer. This will involve studying CRC patients, their families, patients with other cancer types and controls. Secondary aims include determining the extent of that genetic risk, building risk models that incorporate multiple risk factors, and performing functional studies to work out how CRCs develop and how inherited risk factors act. Blood samples, tumour samples, non-cancer material and medical information from study participants is required to perform molecular and statistical analyses.
Dysregulation of DNA repair pathways is known to be involved in the development of colorectal cancer and other cancers. Analysis of additional non-bowel samples from participants with and without germline mutations will aid in understanding why particular germline mutations lead to the development of tumours specifically in the bowel. Characterisation of inherited predispositions is further aided by analysis in the context of other cancers and conditions, which will be assessed by inclusion of other cancers and healthy controls, and by means of questionnaires focusing on cancer history, fertility and birth defects.