The Lynch Syndrome is also known as hereditary non-polyposis colorectal cancer. Which of the following is/are features of this syndrome?

b. Autosomal dominant inheritance

The most widely investigated familial cancer of the colon is the heredity non-polyposis colorectal cancer (HNPCC). HNPCC syndrome is divided into two main categories: (1) hereditary site-specific colon cancer, or Lynch Syndrome I, and (2) colorectal cancer in association with other forms of cancer or Lynch Syndrome II. The main features of Lynch Syndrome I are an autosomal dominant model of heredity, no associated polyposis, right-sided colon cancers, multiple colon cancers, and long survival. In Lynch Syndrome II, many of the characteristics are the same as Syndrome I, with the added burden of increased risk for endometrial, ovarian, stomach, and urinary tract tumors. The HNPCC group comprises nearly 5% of all colorectal cancers, and in some centers, this figure approaches 15 to 20%. The potential for control of this form of colorectal cancer lies in use of computer registries and clinical surveillance of the high risk group. The molecular basis of HNPCC has been identified as defective DNA mismatch repair gene(s).