title: Evaluation of six different DNA extraction methods for detection of Mycobacterium tuberculosis by means of PCR-IS6110: preliminary study.
abstract: BACKGROUND
  Developments in molecular detection and strain differentiation of members of Mycobacterium tuberculosis complex have proved to be useful. The DNA extraction method influences the amplification efficiency, causing interference on the sensitivity and respective inhibitors. The aim of this study was to standardize a simple and fast DNA extraction method, providing DNA amplification by IS6110-PCR effectively free from undue interferences.
  
  
  RESULTS
  The efficiency of the six different protocols tested in M. tuberculosis cultures has varied from 75% to 92.5%. This preliminary study evaluating the IS6110 PCR sensitivity and specificity was developed in DNA extracted from microscope slides, and achieved 100% of efficiency.
  
  
  CONCLUSIONS
  DNA extraction by Chelex + NP-40 method from both, cultures of M. tuberculosis and smear slides, resulted in good quantity of interference free DNA, especially in samples with low concentrations of genetic material; therefore, such technique may be used for the molecular diagnosis of tuberculosis.
authors.forename: Isabela Neves
authors.initials: IN
authors.lastname: De Almeida
authors.forename: Wânia
authors.initials: W
authors.lastname: Da Silva Carvalho
authors.forename: Maria Lúcia
authors.initials: ML
authors.lastname: Rossetti
authors.forename: Elis Regina Dalla
authors.initials: ER
authors.lastname: Costa
authors.affiliation: Research Group Coordinator FM/UFMG_REDE-TB, Belo Horizonte, Minas Gerais, Brazil. silvanaspindola@gmail.com.
authors.forename: Silvana Spindola
authors.initials: SS
authors.lastname: De Miranda
mesh_terms: D015373:Bacterial Typing Techniques; D004269:DNA, Bacterial / Q000302:isolation & purification*; D005260:Female; D006801:Humans; D008297:Male; D009169:Mycobacterium tuberculosis / Q000302:isolation & purification*; D017830:Octoxynol; D011092:Polyethylene Glycols / Q000737:chemistry; D016133:Polymerase Chain Reaction / Q000592:standards*; D011137:Polystyrenes / Q000737:chemistry; D011145:Polyvinyls / Q000737:chemistry; D012680:Sensitivity and Specificity; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis* / Q000382:microbiology
chemical_list: D004269:DNA, Bacterial; D011137:Polystyrenes; D011145:Polyvinyls; D011092:Polyethylene Glycols; C006960:chelex; D017830:Octoxynol; C010615:Nonidet P-40