title: Pattern of variation in the mono- and dinucleotide repeat microsatellites associated with lynch syndrome in an Indian population.
abstract: BACKGROUND
  Microsatellite instability (MSI) is associated with Lynch syndrome and hence is a surrogate marker for defective mismatch repair genes. The aim of this study was to investigate the degree of instability associated with each of the 5 microsatellite (MS) loci recommended by the National Cancer Institute (NCI), USA within an Indian population of mixed ethnicity and suffering from Lynch syndrome.
  
  
  METHODS
  DNA from clinical samples originating from the study population (n = 130) were subjected to automated fragment analysis for all 5 MS loci, and data generated were analyzed to determine the frequency of variation of each of the MS in the resource population.
  
  
  RESULTS
  Out of 130, 116 samples responded to polymerase chain reaction (PCR) for all 5 MS loci. 21 (16.15%) were MSI-high (MSI-H) while 27 (20.76%) and 68 (52.30%) were MSI-low (MSI-L) and microsatellite stable (MSS), respectively. D5S346 exhibited the highest instability (27 out of a total of 82 cases of instability recorded for all 5 MS in all 116 patients tested) followed by D2S123 (23/82), BAT26 (14/82), BAT25 (11/82), and D17S250 (7/82).
  
  
  CONCLUSIONS
  MS D17S250 and BAT25 of the 5 MS panel recommended by the NCI are not informative enough and hence should be avoided for diagnosing Lynch syndrome in the Indian population.
authors.affiliation: SN Genelab and Research Center, Surat, India.
authors.forename: Salil
authors.initials: S
authors.lastname: Vaniawala
authors.forename: Arpan
authors.initials: A
authors.lastname: Acharya
authors.forename: Harsh
authors.initials: H
authors.lastname: Parekh
authors.forename: Anuja
authors.initials: A
authors.lastname: Bapat
authors.forename: Pratap N
authors.initials: PN
authors.lastname: Mukhopadhyaya
mesh_terms: D000328:Adult; D003123:Colorectal Neoplasms, Hereditary Nonpolyposis / Q000235:genetics*; D018900:Dinucleotide Repeats / Q000235:genetics*; D005260:Female; D014644:Genetic Variation; D006801:Humans; D007194:India; D008297:Male; D053842:Microsatellite Instability; D008875:Middle Aged; D016133:Polymerase Chain Reaction / Q000379:methods