title: Quasimonomorphic mononucleotide repeats for high-level microsatellite instability analysis.
abstract: Microsatellite instability (MSI) analysis is becoming more and more important to detect sporadic primary tumors of the MSI phenotype as well as in helping to determine Hereditary Non-Polyposis Colorectal Cancer (HNPCC) cases. After some years of conflicting data due to the absence of consensus markers for the MSI phenotype, a meeting held in Bethesda to clarify the situation proposed a set of 5 microsatellites (2 mononucleotide repeats and 3 dinucleotide repeats) to determine MSI tumors. A second Bethesda consensus meeting was held at the end of 2002. It was discussed here that the 1998 microsatellite panel could underestimate high-level MSI tumors and overestimate low-level MSI tumors. Amongst the suggested changes was the exclusive use of mononucleotide repeats in place of dinucleotide repeats. We have already proposed a pentaplex MSI screening test comprising 5 quasimonomorphic mononucleotide repeats. This article compares the advantages of mono or dinucleotide repeats in determining microsatellite instability.
authors.affiliation: INSERM U434, CEPH, Paris, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Buhard
authors.forename: Nirosha
authors.initials: N
authors.lastname: Suraweera
authors.forename: Aude
authors.initials: A
authors.lastname: Lectard
authors.forename: Alex
authors.initials: A
authors.lastname: Duval
authors.forename: Richard
authors.initials: R
authors.lastname: Hamelin
mesh_terms: D000483:Alleles; D014408:Biomarkers, Tumor; D015179:Colorectal Neoplasms / Q000235:genetics; D003123:Colorectal Neoplasms, Hereditary Nonpolyposis / Q000235:genetics*; D043243:DNA Sequence, Unstable; D042822:Genomic Instability; D006801:Humans; D018895:Microsatellite Repeats; D009154:Mutation; D010641:Phenotype; D011110:Polymorphism, Genetic; D012091:Repetitive Sequences, Nucleic Acid; D012680:Sensitivity and Specificity; D017422:Sequence Analysis, DNA
chemical_list: D014408:Biomarkers, Tumor