Adult family members of someone with a faulty PMS2 gene can have genetic testing to check who has the faulty gene and who does not. Their doctor can refer them to a genetic service to find out more about their chance of developing cancer and what genetic testing involves.
If a person does have the faulty PMS2 gene:
- they can pass it on to their children
- each child has a 50% (1 in 2) chance of being born with it. Pregnancy planning options are available to people who want to prevent the faulty gene from being passed on.
When two people with the faulty PMS2 gene have children together, each child has a 25% (1 in 4) chance of being born with two faulty PMS2 genes. People with two faulty PMS2 genes have constitutional mismatch repair deficiency (CMMRD). People with CMMRD have an increased chance of developing cancer from childhood - see ‘Facts for people and families with a constitutional mismatch repair deficiency' – eviq.org.au/p/4057.
If a person does not have the faulty PMS2 gene:
- they have the same chance of developing cancer as the general population (unless there are other factors that increase this risk)
- they cannot pass it on to their children.
|People who decide not to have genetic testing should still get advice about managing their chance of developing cancer.