Early Stage Molecular Markers tf golorectal gancer

golorectal cancer (gRg) has been most prevalent in developed countries. Both genetics andenvironmental factor have been consider in gRg. In gRg or Adenoma several forms of genomicinstability have been identified, including chromosomal instability (gIN), microsatellite instability(MSI), and Epigenetic gene silencing(DNA methylation). Detection of gRg in early stages can reduceboth the incidence and mortality of the disease. garcinoembryonic antigen (gEA) and carbohydrateantigen (gA) are the two important tumor markers of gRg but they are not early stage indicator andspecific markers. So those early stage molecular markers should be considered. There is severalkind of marker that can be mentioned as below: RAS family (including HRAS, NRAS and KRAS) thatencode membrane protein like GTP- binding protein and Adenomatous polyposis coli (APg) gene asmost crucial gatekeeper of colonic epithelial cell proliferation are most important gIN marker thatcould be applied in early stage of gRg. Bethesda markers(a 5 biomarkers panel that consists of 2mononucleotide loci (BAT25 and BAT26) and 3 dinucleotide loci (D2S123, D5S346, and D17S250))based on PgR methods has been developed to assess MSI disorders. Hyper methylation in gpGregions like SEPT9 and MLH1 gene are favorable factor of in gRg patients by epigenetic disorder.Detection of intact unfragments sequences of 1200- 1800 bp long in the stool that are due todiminished rate of apoptosis in gRg beside Faecal occult blood test (FtBT ) as an non invasive andnon specific test is common among diagnostic tests. Although DNA-based fecal markers arepromising but now are not widely used in clinical settings because of inhibitors such as bilirubin andbile acids. Instead FtBT is more routine and as a challenge in coming years molecular based test willhave important position.