title: Real-time relative qPCR without reference to control samples and estimation of run-specific PCR parameters from run-internal mini-standard curves.
abstract: BACKGROUND
  Real-Time quantitative PCR is an important tool in research and clinical settings. Here, we describe two new approaches that broaden the scope of real-time quantitative PCR; namely, run-internal mini standard curves (RIMS) and direct real-time relative quantitative PCR (drqPCR). RIMS are an efficient alternative to traditional standard curves and provide both run-specific and target-specific estimates of PCR parameters. The drqPCR enables direct estimation of target ratios without reference to conventional control samples.
  
  
  RESULTS
  In this study, we compared RIMS-based drqPCR with classical quantifications based on external standard curves and the "comparative Ct method". Specifically, we used a raw real-time PCR dataset as the basis for more than two-and-a-half million simulated quantifications with various user-defined conditions. Compared with classical approaches, we found that RIMS-based drqPCR provided superior precision and comparable accuracy.
  
  
  CONCLUSIONS
  The obviation of referencing to control samples is attractive whenever unpaired samples are quantified. This may be in clinical and research settings; for instance, studies on chimerism, TREC quantifications, copy number variations etc. Also, lab-to-lab comparability can be greatly simplified.
authors.affiliation: Department of Clinical Immunology, University Hospital of Aarhus, Skejby, Denmark. jejensen@rm.dk
authors.forename: Jens Magnus
authors.initials: JM
authors.lastname: Bernth Jensen
authors.forename: Mikkel Steen
authors.initials: MS
authors.lastname: Petersen
authors.forename: Marc
authors.initials: M
authors.lastname: Stegger
authors.forename: Lars J
authors.initials: LJ
authors.lastname: Østergaard
authors.forename: Bjarne K
authors.initials: BK
authors.lastname: Møller
mesh_terms: D008962:Models, Theoretical; D016133:Polymerase Chain Reaction / Q000379:methods*; D012015:Reference Standards; D015203:Reproducibility of Results