National Center for Advancing and Translational Sciences Genetic and Rare Diseases Information Center, a program of the National Center for Advancing and Translational Sciences

Lynch syndrome

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

The following information may help to address your question:


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.[1][2] Treatment of colon cancer is surgical removal of the affected part of the colon (colectomy). People with Lynch syndrome should have routine colonoscopies.[2]
Last updated: 4/13/2017

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.[1][2]
Last updated: 4/13/2017

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.[1]
Last updated: 4/13/2017

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.[2]

To read detailed diagnostic strategies, please visit the following link from GeneReviews: http://www.ncbi.nlm.nih.gov/books/NBK1211/#hnpcc.Diagnosis
Last updated: 4/13/2017

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: 7/1/2011

How can I find a genetics professional in my area?

To find a medical professional who specializes in genetics, you can ask your doctor for a referral or you can search for one yourself. Online directories are provided by the American College of Medical Genetics and the National Society of Genetic Counselors. If you need additional help, contact a GARD Information Specialist. You can also learn more about genetic consultations from Genetics Home Reference.
Last updated: 12/6/2017

We hope this information is helpful. We strongly recommend you discuss this information with your doctor. If you still have questions, please contact us.

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GARD Information Specialist

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  1. Lynch syndrome. Genetics Home Reference Web site. April 11, 2017; http://ghr.nlm.nih.gov/condition=lynchsyndrome.
  2. Kohlmann W & Gruber S. Lynch syndrome. GeneReviews. May 22, 2014; http://www.ncbi.nlm.nih.gov/books/NBK1211/.