Researchers at the Genetics and Epidemiology of Colorectal Cancer Consortium have been studying the genetic links to colon cancer in approximately 40,000 participants, half of who have colorectal cancer. There are many possible risk factors of colon cancer, and a very small percentage of colon cancer cases are caused by genetic variants, mutations in a person’s genes. However, the study found four specific variants that are associated with colon cancer.
They conducted a genomewide-association study, which involves two phases. The researchers rapidly scan complete sets of blood DNA from 12,696 people with colorectal cancer or a precancerous condition called adenoma, and then the data is compared to the same set of variants from 15,113 healthy controls. The researchers then concentrated on the 10 most statistically significant mutations associated with colorectal cancer. These mutations were further analyzed in a follow-up genomewide-association study of 3,056 colorectal cancers or adenomas and colon-tissue samples from 6,658 noncancerous controls.
After this follow-up study, they found four genetic variants: NABP, a gene involved in DNA repair, LAMC1, the second gene in the laminin gene family found to be associated with colorectal cancer, CCND2, a gene involved in cell-cycle control, which is a key control mechanism to prevent cancer development, and TBX3, a gene transcription factor that targets a known colorectal cancer pathway. If a person carries one or two copies of these variants, their risk of colon cancer increases to 40 percent compared to those without these mutations.
These findings provide researchers with information that can help them create new drugs that will target these genes and slow the spread of cancer cells (Source: Science Daily).