title: A636P is associated with early-onset colon cancer in Ashkenazi Jews.
abstract: BACKGROUND
  Hereditary predisposition to colorectal cancer most often manifests itself as familial adenomatous polyposis from mutations of APC, or hereditary nonpolyposis colorectal cancer, resulting from mutations of MSH2, MLH1, MSH6, or other genes. Previously, we described a rare founder mutation MSH2*1906C > G in Ashkenazi Jews that was found in 8 of 1,345 individuals (0.6%) of Ashkenazi descent with colorectal cancer. This study seeks to characterize the proportion of individuals of Ashkenazi heritage with very early-onset colon cancer (diagnosed at age 40 or younger) that could be attributed to MSH2*1906C>G.
  
  
  METHODS
  We analyzed the carrier frequency of MSH2*1906C>G in paraffin samples from 31 Jewish patients age 40 or less, diagnosed with colorectal cancer at Memorial Sloan-Kettering and lymphocyte-derived DNA from 10 patients. We did not select for family history. Genotyping for MSH2*1906C>G was performed by polymerase chain reaction and restriction enzyme digestion methods.
  
  
  RESULTS
  We detected the MSH2*1906G>C mutation in 3 of the 41 samples (7.14%) of patients who had colorectal cancer diagnosed at age 40 or younger. This incidence is significantly greater than the 8 in 1,345 (0.6%) we observed for cases of colorectal cancer in Ashkenazi Jews not selected for age (p = 0.004).
  
  
  CONCLUSIONS
  Although very rare in the population, MSH2*1906G>C is found at an increased frequency in young Jewish patients with colorectal cancer. These results suggest that testing for the MSH2*1906G>C mutation should be included in the evaluation of Ashkenazi Jewish individuals diagnosed with early-onset colon cancer.
authors.affiliation: Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA.
authors.forename: José G
authors.initials: JG
authors.lastname: Guillem
authors.forename: Beth S
authors.initials: BS
authors.lastname: Rapaport
authors.forename: Tomas
authors.initials: T
authors.lastname: Kirchhoff
authors.forename: Prema
authors.initials: P
authors.lastname: Kolachana
authors.forename: Khedoudja
authors.initials: K
authors.lastname: Nafa
authors.forename: Emily
authors.initials: E
authors.lastname: Glogowski
authors.forename: Rob
authors.initials: R
authors.lastname: Finch
authors.forename: Helen
authors.initials: H
authors.lastname: Huang
authors.forename: William D
authors.initials: WD
authors.lastname: Foulkes
authors.forename: Arnold
authors.initials: A
authors.lastname: Markowitz
authors.forename: Nathan A
authors.initials: NA
authors.lastname: Ellis
authors.forename: Kenneth
authors.initials: K
authors.lastname: Offit
mesh_terms: D000328:Adult; D017668:Age of Onset; D020132:Anticipation, Genetic / Q000235:genetics; D003110:Colonic Neoplasms / Q000453:epidemiology* / Q000235:genetics*; D003123:Colorectal Neoplasms, Hereditary Nonpolyposis / Q000453:epidemiology* / Q000235:genetics*; D004252:DNA Mutational Analysis / Q000379:methods; D004268:DNA-Binding Proteins; D005061:Europe, Eastern; D018703:Founder Effect; D006580:Genetic Carrier Screening; D020022:Genetic Predisposition to Disease / Q000453:epidemiology / Q000235:genetics*; D006801:Humans; D007585:Jews / Q000235:genetics*; D008297:Male; D051718:MutS Homolog 2 Protein; D009154:Mutation / Q000235:genetics; D011518:Proto-Oncogene Proteins / Q000235:genetics*
chemical_list: D004268:DNA-Binding Proteins; D011518:Proto-Oncogene Proteins; C497172:MSH2 protein, human; D051718:MutS Homolog 2 Protein