title: [Molecular characteristics of Clustered Regularly Interspaced Short Palindromic Repeat in Shigella].
abstract: OBJECTIVE
  To detect the molecular characteristics of Clustered Regularly Interspaced Short Palindromic Repeat (CRISPR) in Shigella and to analyze the distribution of CRISPR related to the time of isolation.
  
  
  METHODS
  Of the 52 Shigella strains, 41 were isolated from Henan, 6 from Jiangxi and 5 isolated from Beijing. Both CRISPR locus of S1, S2, S3 and S4 in Shigella were detected by polymerase chain reaction (PCR). The PCR products were sequenced and compared.
  
  
  RESULTS
  The positive rates of CRISPR locus in Shigella were 33.69% (S1), 50.00% (S2), 82.69% (S3) and 73.08% (S4), respectively. Two subtypes were discovered in S1 and S3 locus. Three subtypes were discovered in S2 locus. Four different subtypes were discovered in S4 locus. The isolates from Henan strains were divided into two groups by the time of isolation. Distributions of S1 were different, before or after 2004, on Shigella. S1 could not be detected after 2004. There were no statistical differences of S2, S3 and S4 in two groups.
  
  
  CONCLUSIONS
  Different CRISPR subtypes or Shigella were discovered. A significant correlation was noticed between the CRISPR S1 related to the time of isolation but not between S2, S3 or S4 on the time of isolation.
authors.affiliation: Xi'an Municipal Center for Disease Control and Prevention, Xi'an 710054, China; School of Public Health, Zhengzhou Universtiy.
authors.forename: Zerun
authors.initials: Z
authors.lastname: Xue
authors.affiliation: Henan University of Science and Technology.
authors.forename: Yingfang
authors.initials: Y
authors.lastname: Wang
authors.affiliation: School of Public Health, Zhengzhou Universtiy; Henan Innovation Center of Molecular Diagnosis and Laboratory Medicine, Xinxiang Medical University; Email: gcduan@zzu.edu.cn.
authors.forename: Guangcai
authors.initials: G
authors.lastname: Duan
authors.affiliation: School of Public Health, Zhengzhou Universtiy.
authors.forename: Haiyan
authors.initials: H
authors.lastname: Yang
authors.affiliation: School of Public Health, Zhengzhou Universtiy.
authors.forename: Yuanlin
authors.initials: Y
authors.lastname: Xi
authors.affiliation: School of Public Health, Zhengzhou Universtiy.
authors.forename: Pengfei
authors.initials: P
authors.lastname: Wang
authors.affiliation: School of Public Health, Zhengzhou Universtiy.
authors.forename: Linlin
authors.initials: L
authors.lastname: Wang
authors.affiliation: School of Public Health, Zhengzhou Universtiy.
authors.forename: Xiangjiao
authors.initials: X
authors.lastname: Guo
mesh_terms: D064112:Clustered Regularly Interspaced Short Palindromic Repeats; D016133:Polymerase Chain Reaction; D012760:Shigella / Q000235:genetics*