HNPCC Kit 1 - FL

HNPCC kit 1 – FL allows microsatellites instability analysis in tumor-associated HNPCC and in sporadic colon and stomach cancer by multiplex PCR followed by capillary electrophoresis.

HNPCC (hereditary nonpolyposis colorectal cancer) is an autosomal dominant genetic condition that predisposes to the early development of several cancers including the colon, rectum, endometrium, ovary, small intestine, stomach and urinary tract ones.

HNPCC is caused by germline mutations in genes encoding proteins responsible for the repair of DNA replication errors, which are called DNA mismatch repair (MMR) genes. DNA mismatch repair machinery plays a critical role in genomic stability, including correction of mispaired bases associated with DNA replication and recombination. Germinal mutations in one allele of any of these genes, with subsequent somatic loss or inactivation of the wild-type allele, leads to a defective mismatch repair mechanism.

The current “gold standard” for assessing tumor DNA MMR activity is molecular microsatellite instability (MSI) testing.

The microsatellite instability phenotype, characterized by widespread somatic alterations in the length of nucleotide repeat sequences, is observed in almost HNPCC associated tumor and in 10-15% sporadic gastric and colon cancer. MSI is a valuable diagnostic marker for the identification of HNPCC cases and a molecular predictive marker for the identification of colon cancer patients who benefit from chemotherapy.

MSI in tumor is defined as the presence of alternate-sized repetitive DNA sequences that are not seen on the corresponding germline DNA. Depending on the the number of microsatellites found to be unstable, tumors are classified as stable (MSS), with low instability (MSI-L) and with high instability (MSI-H).