title: Interlaboratory study of DNA extraction from multiple ground samples, multiplex real-time PCR, and multiplex qualitative PCR for individual kernel detection system of genetically modified maize.
abstract: In many countries, the labeling of grains, feed, and foodstuff is mandatory if the genetically modified (GM) organism content exceeds a certain level of approved GM varieties. We previously developed an individual kernel detection system consisting of grinding individual kernels, DNA extraction from the individually ground kernels, GM detection using multiplex real-time PCR, and GM event detection using multiplex qualitative PCR to analyze the precise commingling level and varieties of GM maize in real sample grains. We performed the interlaboratory study of the DNA extraction with multiple ground samples, multiplex real-time PCR detection, and multiplex qualitative PCR detection to evaluate its applicability, practicality, and ruggedness for the individual kernel detection system of GM maize. DNA extraction with multiple ground samples, multiplex real-time PCR, and multiplex qualitative PCR were evaluated by five laboratories in Japan, and all results from these laboratories were consistent with the expected results in terms of the commingling level and event analysis. Thus, the DNA extraction with multiple ground samples, multiplex real-time PCR, and multiplex qualitative PCR for the individual kernel detection system is applicable and practicable in a laboratory to regulate the commingling level of GM maize grain for GM samples, including stacked GM maize.
authors.affiliation: National Institute of Health Sciences, 1-18-1 Kamiyoga, Setagaya-ku, Tokyo 158-8501, Japan. akiyama@nihs.go.jp
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Akiyama
authors.forename: Kozue
authors.initials: K
authors.lastname: Sakata
authors.forename: Daiki
authors.initials: D
authors.lastname: Makiyma
authors.forename: Kosuke
authors.initials: K
authors.lastname: Nakamura
authors.forename: Reiko
authors.initials: R
authors.lastname: Teshima
authors.forename: Akie
authors.initials: A
authors.lastname: Nakashima
authors.forename: Asako
authors.initials: A
authors.lastname: Ogawa
authors.forename: Toru
authors.initials: T
authors.lastname: Yamagishi
authors.forename: Satoshi
authors.initials: S
authors.lastname: Futo
authors.forename: Taichi
authors.initials: T
authors.lastname: Oguchi
authors.forename: Junichi
authors.initials: J
authors.lastname: Mano
authors.forename: Kazumi
authors.initials: K
authors.lastname: Kitta
mesh_terms: D017931:DNA Primers; D018744:DNA, Plant / Q000235:genetics* / Q000302:isolation & purification*; D060885:Multiplex Polymerase Chain Reaction / Q000379:methods*; D030821:Plants, Genetically Modified / Q000737:chemistry / Q000235:genetics*; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods*; D015203:Reproducibility of Results; D012639:Seeds / Q000737:chemistry; D003313:Zea mays / Q000737:chemistry / Q000235:genetics*
chemical_list: D017931:DNA Primers; D018744:DNA, Plant