Collaborative trial validation of cry1Ab/Ac and Pubi-cry TaqMan-based real-time PCR assays for detection of DNA derived from genetically modified Bt plant products

Validation of qualitative PCR methods on the basis of mathematical–statistical modelling of the probability of detection

“…Furthermore, systematic errors affecting the determination of the nominal number of DNA copies at the first dilution level must be taken into consideration. Indeed, the determination of the original number of DNA copies is subject to uncertainties which will propagate (see Grohmann et al [11]). This is true both for a test sample obtained by dilution from a stock solution and for a sample produced in advance of the validation study and prepared by another procedure.…”

“…Seventeen laboratories participated in a collaborative study for a qualitative PCR method for the detection of Pubi-cry (see Grohmann et al [11]). Each participant received a sample DNA stock solution and a dilution buffer.…”

“…For each dilution level, the nominal number of DNA copies and the number of positive PCR test results per participant were used for the evaluation (Table 1). Details on the PCR method and the design of the collaborative study are described elsewhere [11].…”

Efficient estimation of the limit of detection and the relative limit of detection along with their reproducibility in the validation of qualitative microbiological methods by means of generalized linear mixed models

“…While the concept of reproducibility is easily interpreted for qualitative methods in terms of consistent test results across laboratories for samples with the same level of contamination, it is not clear at all how to describe or characterize a qualitative method's reproducibility in such a way as to make possible a comparison to criteria or other methods. In the last few years, however, novel validation approaches have been proposed for the characterization of the reproducibility of a qualitative method (Uhlig et al 2011(Uhlig et al , 2013Grohmann et al 2015).…”

Novel TaqMan PCR screening methods for element cry3A and construct gat/T-pinII to support detection of both known and unknown GMOs

“…Therefore, additional detection methods are sometimes necessary in order to target specific (groups of) GMOs. Some recent examples of additional qPCR screening methods are the element bar and construct ctp2/cp4epsps [21], the elements cry1A.105 and cry2Ab2 [15], promoters P-FMV, P-nos, P-SSuAra, P-TA29, P-ubi, P-rice actin and terminators T-35S, T-E9, T-ocs, T-g7 [14], element vip3A [29], and element cry1Ab/Ac and construct P-ubi/cry [22]. Recent examples of SYBR ® Green detection methods are P-nos and P-FMV [9], cry3Bb and gat/T-pinII [10], and the application of Combinatory SYBR ® Green PCR Screening (CoSYPS) [4,30,42].…”