What is the HNPCC gene?
Hereditary nonpolyposis colorectal cancer (HNPCC) or Lynch syndrome is an autosomal dominant genetic condition that is associated with a high risk of colon cancer as well as other cancers including endometrial cancer (second most common), ovary, stomach, small intestine, hepatobiliary tract, upper urinary tract, brain.
Is HNPCC recessive or dominant?
HNPCC is an autosomal dominant condition. This means that people with HNPCC have a 50% chance of passing the HNPCC gene mutation (change) to each of their children.
How do you know if you have Muir Torre syndrome?
A person is suspected to have Muir-Torre syndrome (MTS) if he/she has one or more of the following: History of one or more sebaceous tumors. Age younger than 60 years at first presentation of sebaceous tumors. Personal history of Lynch-related cancers.
How is HNPCC detected?
There are two screening examinations for colorectal cancer and HNPCC:
- Sigmoidoscopy—a diagnostic procedure that allows the doctor to examine the lower one-third of the large intestine.
- Colonoscopy—a diagnostic procedure that allows the physician to examine the entire length of the large intestine.
What are the genes responsible for HNPCC?
The genes responsible for HNPCC are mismatch-repair genes, which correct “spelling errors” in DNA that happen during the cell division process. When these genes are altered, or mutated, however, mismatches in the DNA remain.
What is HNPCC and how common is it?
It is one of the most common cancer predisposing syndromes affecting as many as one in 400 individuals in the Western World. Two (mismatch repair) genes (hMSH2 on chromosome 2p and hMLH1 on chromosome 3p) have recently been identified which appear to be involved in the development of cancer in most of the HNPCC families.
What is hereditary nonpolyposis colorectal cancer (HNPCC)?
Hereditary nonpolyposis colorectal cancer (HNPCC) is an autosomal dominantly inherited disease associated with a marked increase in cancer susceptibility, especially cancer of the colorectum. It is one of the most common cancer predisposing syndromes affecting as many as one in 400 individuals in the Western World.
What is the best screening test for HNPCC?
For patients at risk for HNPCC, colonoscopy is the preferred method of screening. Genetic Testing. Mutations (alterations) of one of five genes are now known to be responsible for most cases of HNPCC. These genes are called hMSH2, hPMS1, MSH6 (all on chromosome 2), hMLH1 (chromosome 3), and hPMS2 (chromosome 7).