Predictive testing

Lynch syndrome genetic and predictive testing

This is for people where genetic testing has already been carried out in your family and has confirmed that a mutation (fault) in a Lynch syndrome gene is present in your family. This is called a familial Lynch syndrome mutation. 

You can have a test to see if you have inherited the same mutation. This is called a predictive test and it involves taking a blood sample.

Before we offer you a predictive test we will discuss with you what the test could mean for you and your family.  We will give you the opportunity to ask questions.

Your genetics clinician will talk to you about the many things to consider before deciding, you can read more about deciding whether to be tested

Predictive gene tests take up to 8 weeks once your blood sample has been received and we have all the information needed to carry out the test. Once the result is ready, you will be contacted and if appropriate offered further appointments.

Results of predictive testing

Predictive testing will confirm that either:

You have not inherited the familial Lynch syndrome mutation 

  • Although an inherited tendency to developing bowel cancer is present in your family, you have not inherited it.
  • Your own risk of developing Lynch syndrome-related cancers is not higher than anyone in the general population.
  • As you do not have the mutation you cannot pass it on to your children. 

You have inherited the familial Lynch syndrome mutation

  • You will have an increased chance of developing the cancers associated with Lynch syndrome but it does not mean that you will definitely develop any of these cancers.

Resource number 4200/VER3
Published date March 2023
Review date March 2026

Trusted Information Creator. Patient Information Forum

Contact us

If you have any questions or concerns, please contact your genetics clinician.

Phone: 020 7188 1364 Monday to Friday, 9am to 5pm.

Cancer Genetics Service, Guy’s Regional Genetics Service
Guy’s Hospital
Great Maze Pond
London SE1 9RT

Do you have any comments or concerns about your care?

Contact our Patient Advice and Liaison Service (PALS)

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