title: Qualitative and Quantitative PCR-Based Detection Methods for Authorized Genetically Modified Cotton Events in India.
abstract: Qualitative diagnostics for all five commercialized genetically modified (GM) cotton events for insect resistance in India is being reported for the first time in this paper. The cost-effective and robust multiplex PCR (MPCR)-based detection assay, distinguishing the insect resistant transgenic Bt cotton events, viz., MON531, MON15985, Event 1, GFM-cry1A, and MLS-9124, has been developed. This decaplex PCR assay targets nine transgenic elements, viz., sequences of four transgenes, three transgene constructs, and two event-specific sequences along with one endogenous reference gene. The LOD of the qualitative MPCR assay was up to 0.1%. A quantitative detection method for four widely commercially cultivated GM cotton events, namely, MON531, MON15985, Event 1, and GFM-cry1A, covering 99.5% of the total area under GM cultivation in the country, is also reported. A construct-specific real-time PCR assay has been developed for quantification of these GM cotton events with LOQ <0.05% and LOD <0.025%. The developed assays will be of great use to screen for the presence/absence of authorized GM cotton events in unknown samples and to check the authenticity of GM cotton seed samples.
authors.affiliation: Indian Council of Agricultural Research - National Bureau of Plant Genetic Resources, Genomic Resources Division, New Delhi 110 012, India.
authors.forename: Rashmi
authors.initials: R
authors.lastname: Chhabra
authors.forename: Gurinder Jit
authors.initials: GJ
authors.lastname: Randhawa
authors.forename: Rajesh K
authors.initials: RK
authors.lastname: Bhoge
authors.forename: Monika
authors.initials: M
authors.lastname: Singh
mesh_terms: D003368:Gossypium / Q000235:genetics*; D057230:Limit of Detection; D060885:Multiplex Polymerase Chain Reaction / Q000379:methods*; D030821:Plants, Genetically Modified / Q000235:genetics*; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods*; D015203:Reproducibility of Results; D019076:Transgenes