title: Evaluation of a Modified DNA Extraction Method for Isolation of Cell-Free Fetal DNA from Maternal Serum.
abstract: BACKGROUND
  Discovery of short cell free fetal DNA (cffDNA) fragments in maternal plasma has created major changes in the field of prenatal diagnosis. The use of cffDNA to set up noninvasive prenatal test is limited due to the low concentration of fetal DNA in maternal plasma therefore, employing a high efficiency extraction method leads to more accurate results. The aim of this study was to evaluate the efficiency of Triton/Heat/Phenol (THP) protocol in comparison with the QIAamp DNA Blood mini Kit for cffDNA purification.
  
  
  METHODS
  In order to evaluate the efficiency of THP protocol, DNA of Rhesus D (RhD) negative pregnant women's plasma was collected, then real-time PCR for RHD exon 7 was performed. The Ct value data of real time PCR obtained by two different methods were compared and after delivery serology test on cord blood was done to validate the real time PCR results.
  
  
  RESULTS
  The results indicated significant differences between two extraction methods (p=0.001). The mean±SD of Ct-value using THP protocol was 33.8±1.6 and 36.1±2.47 using QIAamp DNA Blood mini Kit.
  
  
  CONCLUSIONS
  Our finding demonstrated that THP protocol was more effective than the QIAamp DNA Blood mini Kits for cffDNA extraction and lead to decrease the false negative results.
authors.affiliation: Diagnostic Laboratory Sciences and Technology Research Center, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran ; Student Research Committee, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Zeinab
authors.initials: Z
authors.lastname: Keshavarz
authors.affiliation: Diagnostic Laboratory Sciences and Technology Research Center, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Leili
authors.initials: L
authors.lastname: Moezzi
authors.affiliation: Diagnostic Laboratory Sciences and Technology Research Center, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Reza
authors.initials: R
authors.lastname: Ranjbaran
authors.affiliation: Diagnostic Laboratory Sciences and Technology Research Center, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Farzaneh
authors.initials: F
authors.lastname: Aboualizadeh
authors.affiliation: Diagnostic Laboratory Sciences and Technology Research Center, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Abbas
authors.initials: A
authors.lastname: Behzad-Behbahani
authors.affiliation: Diagnostic Laboratory Sciences and Technology Research Center, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Masooma
authors.initials: M
authors.lastname: Abdullahi
authors.affiliation: Diagnostic Laboratory Sciences and Technology Research Center, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Sedigheh
authors.initials: S
authors.lastname: Sharifzadeh
keywords: Fetus; Prenatal diagnosis; Real time polymerase chain reaction; THP protocol