Lynch syndrome is an autosomal dominant hereditary cancer syndrome, associated with a 40%–80% lifetime risk of developing colorectal, endometrial and other cancers.
Lynch syndrome may be suspected from a family history of bowel cancer and other Lynch syndrome-related cancers, triggering genomic testing in the family.
Lynch syndrome is an autosomal dominant condition, so that each child (son or daughter) and each sibling (brother or sister) of an affected individual has a 50% (1-in-2) chance of inheriting the condition.
It is important to remember that chance has no memory, and the 1-in-2, or 50%, chance of inheriting the altered gene for the condition applies to each child, irrespective of whether or not the parents have already had children with, or without, the condition.
Lynch Syndrome Ireland 