Novel reference molecules for quantitation of genetically modified maize and soybean.
New quantitation methods based on a real-time polymerase chain reaction (PCR) technique were developed for 5 lines of genetically modified (GM) maize, including MON810, Event176, Bt11, T25, and GA21, and a GM soy, Roundup Ready. Oligonucleotide DNA, including specific primers and fluorescent dye-labeled probes, were designed for PCRs. Two plasmids were constructed as reference molecules (RMs) for the detection of GM maize and GM soy. The molecules contain the DNA sequences of a specific region found in each GM line, universal sequences used in various GM lines, such as cauliflower mosaic virus 35S promoter and nopaline synthase terminator, and the endogenous DNA sequences of maize or soy. By using these plasmids, no GM maize and GM soy were required as reference materials for the qualitative and quantitative PCR technique. Test samples containing 0, 0.10, 0.50, 1.0, 5.0, and 10% GM maize or GM soy were quantitated. At the 5.0% level, the bias (mean-true value) ranged from 2.8 to 19.4% and the relative standard deviation was <5.2%. These results show that our method involving the use of these plasmids as RMs is reliable and practical for quantitation of GM maize and GM soy.
Kuribara
Hideo
H
Center for Food Quality, Labeling and Consumer Services, Saitama, Saitama, Japan.
Shindo
Yoichiro
Y
Matsuoka
Takeshi
T
Takubo
Ken
K
Futo
Satoshi
S
Aoki
Nobutaro
N
Hirao
Takashi
T
Akiyama
Hiroshi
H
Goda
Yukihiro
Y
Toyoda
Masatake
M
Hino
Akihiro
A
D001483:Base Sequence; D017931:DNA Primers; D018744:DNA, Plant / Q000737:chemistry / Q000235:genetics; D004587:Electrophoresis, Agar Gel; D001467:Hordeum / Q000737:chemistry; D006813:Humidity; D008969:Molecular Sequence Data; D012275:Oryza / Q000737:chemistry; D010316:Particle Size; D010940:Plant Proteins / Q000032:analysis*; D015203:Reproducibility of Results; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012639:Seeds / Q000737:chemistry; D013025:Glycine max / Q000737:chemistry* / Q000235:genetics*; D014908:Triticum / Q000737:chemistry; D003313:Zea mays / Q000737:chemistry* / Q000235:genetics*
D017931:DNA Primers; D018744:DNA, Plant; D010940:Plant Proteins