5-10%percent of those cases are attributed to gentics. 5% of all cancer diagnoses are related to hereditary nonpolyposis colorectal cancer, or HNCC.
What is HNCC?
HNCC is a syndrome in which the risk of developing colorectal cancer is heightened. It is defined by the mutation of specific genes.
What genes are responsible?
Studies have revealed that most cases of HNCC occur because of mutation to the MLH1 and MSH2 genes. Further studies are being conducted to identify other genes that may be responsible.
Characteristics of HNCC Families
Families with HNCC generally have three factors in common:
- 3 or more closely related family members diagnosed with colorectal cancer
- a family member diagnosed under the age of 50
- colorectal cancer has affected two or more generations
Is genetic testing available?
Genetic testing is available through laboratory tests. DNA is examined thoroughly for mutated MLH1 and MSH2 genes. These genes are sought because studies have shown that they cause almost all cases of HNCC.
