Lynch syndrome

What causes Lynch syndrome?

Lynch syndrome is caused by mutations in at least 5 genes ( MLH1 , MSH2, MSH6, PMS2 _or EPCAM_ ). All of these genes are involved in the repair of mistakes made when DNA is copied (DNA replication) in preparation for cell division. Mutations in any of these genes prevent the proper repair of DNA replication mistakes. As the abnormal cells continue to divide, the accumulated mistakes can lead to uncontrolled cell growth and possibly cancer. Although mutations in these genes predispose individuals to cancer, not all people who carry these mutations develop cancerous tumors.

Last updated on 05-01-20

How is Lynch syndrome diagnosed?

The diagnosis of Lynch syndrome can be made on the basis of the Amsterdam Clinical Criteria or on the basis of molecular genetic testing for germline mutations in one of several mismatch repair (MMR) genes.

To read detailed diagnostic strategies, please visit the following link from GeneReviews:

Last updated on 05-01-20

Is Lynch syndrome an inherited condition?

Lynch syndrome cancer risk is inherited in an autosomal dominant pattern, which means one inherited copy of the mutated gene in each cell is sufficient to increase a person's cancer risk. It is important to note that people inherit an increased risk of cancer, not the disease itself. Not all people who inherit mutations in these genes will develop cancer.

Last updated on 05-01-20

What is Lynch syndrome?

Lynch syndrome is a genetic disorder that causes an increased risk of developing certain types of cancer such as colon and rectal cancer, as well as cancers of the stomach, small intestine, liver, gallbladder ducts, upper urinary tract, brain, skin, and prostate. Women with Lynch syndrome also have a high risk of developing uterine cancer (also called endometrial cancer) and ovarian cancer. Even though the disorder was originally described as not involving noncancerous (benign) growths (polyps) in the colon, people with Lynch syndrome may occasionally have colon polyps. Lynch syndrome has an autosomal dominant pattern of inheritance and is caused by a mutation in the MLH1, MSH2, MSH6, PMS2 or EPCAM gene. Treatment of colon cancer is surgical removal of the affected part of the colon (colectomy). People with Lynch syndrome should have routine colonoscopies.

Last updated on 05-01-20

Is the distinction between Lynch Syndrome I and Lynch Syndrome II still used?

Lynch syndrome is an inherited condition that increases the chance to develop certain types of cancers (a cancer predisposition syndrome). In the past, this condition was divided into two subtypes: Lynch syndrome 1 referred to a condition that increased the chance of developing colon cancer only and Lynch syndrome 2 referred to a condition that increased the chance of developing cancers other than colon cancer, such as cancers of the uterus, stomach, biliary tract and pancreas, and urinary tract. However, it is now known that both Lynch syndrome 1 and Lynch syndrome 2 are caused by mutations in the same genes (MLH1, MSH2, MSH6, PMS2, and EPCAM). Because the underlying genetic cause is similar for both subtypes, they are now referred to as one condition, "Lynch syndrome".

Last updated on 05-01-20

What is the name of the blood test used to diagnose Lynch syndrome?

The Hereditary Non-Polyposis Colon Cancer test is a panel which includes testing for MLH1-Related Hereditary Non-Polyposis Colon Cancer, MLH3-Related Hereditary Non-Polyposis Colon Cancer, MSH2-Related Hereditary Non-Polyposis Colon Cancer, MSH6-Related Hereditary Non-Polyposis Colon Cancer, PMS1-Related Hereditary Non-polyposis Colon Cancer, and PMS2-Related Hereditary Non- Polyposis Colon Cancer.

GeneTests lists laboratories offering clinical genetic testing for this condition. Clinical genetic tests are ordered to help diagnose a person or family and to aid in decisions regarding medical care or reproductive issues. Talk to your health care provider or a genetic professional to learn more about your testing options.

Last updated on 05-01-20

Clinical Research Resources

Lynch Syndrome International

Lynch Syndrome International (LSI) Web site lists Lynch syndrome clinical trials and patient registries. Click on the link above to view the list.

Last updated on 04-27-20

Management Guidelines

Evaluation of Genomic Applications in Practice and Prevention (EGAPP)

Last updated on 04-27-20

Name: American Cancer Society 250 Williams Street NW
Atlanta, GA, 30329, United States
Toll Free: 1-800-227-2345 Url:
Name: Fight Colorectal Cancer 134 West Park Central Square Suite 210
Springfield, MO, 65806, United States
Phone: +1-703-548-1225 (Office) Toll Free: 1-877-427-1211 (Helpline) Email: Url:
Name: Colon Cancer Alliance 1025 Vermont Ave, NW Suite 1066
Washington, DC, 20005, United States
Phone: +1-202-628-0123 (Office) Toll Free: (877) 422-2030 (Helpline) Url:
Name: Cancer Hope Network 2 North Road, Suite A
Chester, NJ, 07930, United States
Phone: +1-908-879-4039 Toll Free: 1-877-467-3638 (1-877-HOPENET) Fax : +1-908-879-6518 Email: Url:
Name: AMC Cancer Research Center 3401 Quebec St, Suite 3200
Denver, CO, 80207, United States
Phone: 303-233-6501 Toll Free: 800-321-1557 Fax : 303-239-3400 Email: Url:
Name: Lynch Syndrome International LSI P.O. Box 19
Madison, CT, 06443, United States
Email: Url: If you would like someone to call you from LSI, please email the Executive Director ( or a leave a message in the Facebook messaging section.
Name: Collaborative Group of the Americas in Inherited Colorectal Cancer (CGA) Url:
Name: CCARE Lynch Syndrome 127 W. Oak Unit C
Chicago, IL, 60610,
Phone: 312-725-9769 Fax : 847-267-0746 Email: Url:
Name: AliveAndKickn PO Box 38
Haworth, NJ, 07641,
Name: Hereditary Colon Cancer Foundation 3519 NE 15th Avenue Unit 518
Portland, OR, 97212, United States
Phone: +1-334-740-8657 Email: Url:

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