title: [Laboratory-performance study of quantitative PCR methods to analyze an approved genetically modified maize (Mon810 Line)].
abstract: A laboratory-performance study was carried out to investigate factors affecting the reliability of the quantitative PCR method to analyze an approved genetically modified (GM) maize (Mon810 line). Test maize powdered samples were prepared as blind samples containing a high (assigned value; 5.45%) or low (assigned value; 0.35%) concentration of the Mon810 line. After confirmation of their homogeneity, they were provided to 27 laboratories participating in the collaborative study. The data were collected from all laboratories and statistically analyzed. Two laboratories, which used a Roche LightCycler (LC), reported significantly high test values. A further examination showed that the LC method is greatly affected by the equipment itself or PCR reagents, resulting in poor repeatability. On the other hand, some laboratories, which used ABI quantitative PCR equipment, reported erroneous test values. In these laboratories, the errors appeared to have been due to inadequate quality and/or yield of DNA. To identify factors affecting the test values, analysis of the measured values for the taxon-specific gene will be useful. Furthermore, the modified silica-gel membrane DNA extraction method made it possible to extract the required amounts of DNA more easily and in a shorter time than before.
authors.affiliation: National Institute of Health Sciences: 1-18-1, Kamiyoga, Setagaya-ku, Tokyo 158-8501, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Watanabe
authors.forename: Kikuko
authors.initials: K
authors.lastname: Kasama
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kikuchi
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Suzuki
authors.forename: Shoko
authors.initials: S
authors.lastname: Tokishita
authors.forename: Kozue
authors.initials: K
authors.lastname: Sakata
authors.forename: Akihiko
authors.initials: A
authors.lastname: Matsuki
authors.forename: Akihiro
authors.initials: A
authors.lastname: Hino
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Akiyama
authors.forename: Tamio
authors.initials: T
authors.lastname: Maitani
mesh_terms: D018744:DNA, Plant / Q000032:analysis / Q000302:isolation & purification; D005504:Food Analysis / Q000379:methods*; D030841:Food, Genetically Modified; D016133:Polymerase Chain Reaction / Q000379:methods* / Q000592:standards; D011786:Quality Control; D015203:Reproducibility of Results; D003313:Zea mays / Q000235:genetics
chemical_list: D018744:DNA, Plant