Colorectal Cancer Panel Sequencing

Colorectal cancer (CRC) is a common malignancy of the digestive tract that occurs in the colon. It usually occurs at the junction of the rectum and the sigmoid colon. Hereditary colorectal cancer is associated with specific genetic abnormalities. With the appreciation and deep understanding of the genetic basis of colorectal cancer, more genes that make people susceptible to CRC may be discovered. Hereditary colorectal cancer includes the following syndromes: hereditary nonpolyposis colon cancer (HNPCC), also known as Lynch syndrome, familial adenomatous polyposis (FAP) and attenuated familial adenomatous polyposis (AFAP), and certain other rare syndromes, such as Cowden syndrome, juvenile polyposis syndrome and Peutz-Jeghers syndrome.

Microsatellite instability (MSI) is an important reason for the occurrence of HNPCC and partial sporadic colorectal cancer. MSI is caused by defecting of the mismatch repair (MMR) genes. MMR genes (mainly MLH1, MSH2, PMS2, and MSH6) may lose function due to mutation, deletion or apparent silencing, thus cannot repair mismatches that occur during DNA replication, resulting in an MSI phenotype. FAP mediates an autosomal dominant inherited disease that usually has mutations of the same gene, and practically all mutations result in C-terminally truncated proteins. The pathogenic variants in the adenomatous polyposis coli (APC) gene, mapped on the long arm of chromosome 5, are responsible for FAP by causing intestinal wall dynamics disorder. When other epithelial cells proliferate abnormally, the APC gene will stabilize the total number of cells, so that would not lead to a sustainable growth perturbation. When the APC gene mutates, the balance between cell division and cell death will be broken permanently, leading to tumor formation. MUTYH protein is involved in the base excision repair (BER) pathway. The MUTYH double allele mutations with different types (nonsense, missense, frameshift and cleavage site mutations, or truncated proteins) are confirmed associated with the occurrence of colorectal cancer.

To support clinical researches, CD-Genomics offers a colorectal cancer panel library related to the genes with increased risk for hereditary colorectal cancer. If necessary, you can choose genes that fit your requirements.