title: Genotypes of Mycobacterium tuberculosis isolates in rural China: using MIRU-VNTR and spoligotyping methods.
abstract: BACKGROUND
  The genotypes of Mycobacterium tuberculosis (MTB) have been found to be related to the risk of transmission and the development of drug resistance of this pathogen. Thus, exploring the molecular characteristics of MTB is helpful for understanding and controlling the spread of strains in areas with a high incidence of tuberculosis.
  
  
  METHODS
  We recruited 512 sputum smear-positive tuberculosis patients from 30 counties from 1 April to 30 June 2010; 503 MTB strains were isolated and 497 were successfully genotyped. We genotyped the strains based on a new 15-locus mycobacterial interspersed repetitive unit-variable number of tandem repeats (MIRU-VNTR) method in combination with spacer-oligonucleotide typing (spoligotyping) technology.
  
  
  RESULTS
  Based on spoligotyping, 487 strains displayed known patterns, and 10 were absent from the current global spoligotyping database (SpolDB4). The predominant spoligotypes belonged to the Beijing or Beijing-like family (81.1%). When we used the new 15-locus (MIRU-15) set for the MIRU-VNTR analysis, 388 different patterns were identified, including 46 clusters and 342 unique patterns. The combination of spoligotyping and MIRU-15 demonstrated a high discriminatory power. The proportion of clusters varied significantly between the Beijing and non-Beijing family strains, but no significant association was observed between multidrug resistance and Beijing family strains.
  
  
  CONCLUSIONS
  The present study demonstrated that the Beijing family strains are the most prevalent in rural China. Spoligotyping in combination with the new MIRU-15 technique is useful for the epidemiological analysis of MTB transmission and could be used as a first-line method for the large-scale genotyping of MTB.
authors.affiliation: From the Department of Chronic Communicable Disease, Center for Disease Control and Prevention of Jiangsu Province , Nanjing.
authors.forename: Wei
authors.initials: W
authors.lastname: Lu
authors.forename: Bing
authors.initials: B
authors.lastname: Lu
authors.forename: Qiao
authors.initials: Q
authors.lastname: Liu
authors.forename: Haiyan
authors.initials: H
authors.lastname: Dong
authors.forename: Yan
authors.initials: Y
authors.lastname: Shao
authors.forename: Yi
authors.initials: Y
authors.lastname: Jiang
authors.forename: Honghuan
authors.initials: H
authors.lastname: Song
authors.forename: Cheng
authors.initials: C
authors.lastname: Chen
authors.forename: Guoli
authors.initials: G
authors.lastname: Li
authors.forename: Weiguo
authors.initials: W
authors.lastname: Xu
authors.forename: Xiuqin
authors.initials: X
authors.lastname: Zhao
authors.forename: Kanglin
authors.initials: K
authors.lastname: Wan
authors.forename: Limei
authors.initials: L
authors.lastname: Zhu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002681:China / Q000453:epidemiology; D016000:Cluster Analysis; D005260:Female; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D008297:Male; D017720:Molecular Epidemiology; D058889:Molecular Typing; D009169:Mycobacterium tuberculosis / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D015995:Prevalence; D012424:Rural Population; D014376:Tuberculosis / Q000453:epidemiology / Q000382:microbiology*; D055815:Young Adult