title: Investigation of false-positive reactions for CBH351 maize in screening PCR analysis.
abstract: Examination for CBH351 maize was conducted by the qualitative polymerase chain reaction (PCR) method in maize grain and maize processed foods obtained in the Tokyo area. The numbers of samples possibly positive in the screening test were 7 of 22 (31.8%) for maize grain samples, 4 of 14 (28.6%) for semi-processed foods, 11 of 30 (36.7%) for canned products, 3 of 30 (10.0%) for maize snacks, 3 of 4 (75%) for tacos and 1 of 3 (33.3%) for tortillas. However, CBH351 maize was not detected in the confirmation test. Therefore, the results of the screening test were false-positive. Since the reaction might have been caused by the base sequences of the 3'-end of primers CaM03-5' and CBH02-3' used in the screening test, a new primer pair was designed. The PCR products obtained with the new primer pair TMC2-5'--TMS2-3' were specific for CBH351 and were not obtained with barley, wheat, rice, RRS, Bt11, or Event176. Thus, the new primer pair shows high specificity. CBH351 maize was detected from samples containing at least 0.05% CBH 351 maize DNA by using this primer pair.
authors.affiliation: Tokyo Metropolitan Institute of Public Health, 3-24-1, Hyakunin-cho, Shinjuku-ku, Tokyo 169-0073, Japan.
authors.forename: Kimio
authors.initials: K
authors.lastname: Monma
authors.forename: Rie
authors.initials: R
authors.lastname: Moriuchi
authors.forename: Naoki
authors.initials: N
authors.lastname: Sagi
authors.forename: Hisatsugu
authors.initials: H
authors.lastname: Ichikawa
authors.forename: Kazue
authors.initials: K
authors.lastname: Satoh
authors.forename: Takashi
authors.initials: T
authors.lastname: Tobe
authors.forename: Kunihiro
authors.initials: K
authors.lastname: Kamata
mesh_terms: D001483:Base Sequence; D017931:DNA Primers; D018744:DNA, Plant / Q000032:analysis / Q000235:genetics / Q000302:isolation & purification; D005189:False Positive Reactions; D005504:Food Analysis / Q000379:methods*; D030841:Food, Genetically Modified; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction / Q000379:methods*; D016415:Sequence Alignment; D014041:Tokyo; D003313:Zea mays / Q000235:genetics
chemical_list: D017931:DNA Primers; D018744:DNA, Plant