Establishing an accurate and rapid method for copy number and zygosity determination can accelerate genetic engineering research process. In this study, droplet digital PCR (ddPCR), an emerging DNA absolute quantifica...Establishing an accurate and rapid method for copy number and zygosity determination can accelerate genetic engineering research process. In this study, droplet digital PCR (ddPCR), an emerging DNA absolute quantification technology, was used to identify single-copy homozygous transgenic lines from a batch of T0 transgenic rapeseed harboring 11 exogenous elements. Copy number of exogenous gene was evaluated in T0 generation based on calculated ratio between transgene and reference CruA gene, single-copy transformants were selected for selfing followed by subsequent zygosity analysis. Single-copy homozygous transgenic plants were successfully screened out in T1 generation by ddPCR.Segregation analysis with T2 seedlings verified that identification results of ddPCR were accurate and reliable. This study provides a novel rapid and accurate method for copy number and zygosity determination in transgenic rapeseed which overcomes disadvantages of traditional Southern analysis and recently developed real-time quantitative method.展开更多
To ensure safe use of genetically modified organisms(GMOs),since 1993,China has made great efforts to establish and improve the safety regulatory system for GMOs.Here,we summarize and analyze the regulatory framework ...To ensure safe use of genetically modified organisms(GMOs),since 1993,China has made great efforts to establish and improve the safety regulatory system for GMOs.Here,we summarize and analyze the regulatory framework of agricultural GMOs,and the progress in regulatory approval of GM crops in China.In general,the development of GMO safety regulations underwent four stages:exploration(1993–2000),development(2001–2010),improvement(2011–2020)and current(2021-present)stage.The first formal regulation was promulgated in 1993,which provided a basis for further development of the regulations,during the exploration stage,when insect-resistant GM cotton,expressing genes from Bacillus thuringiensis(Bt),was approved for cultivation.During the development stage,the Chinese government issued a series of administrative measures,which covered almost all the fields relative to GMO safety when the basic regulatory system was established.Along with the controversy over GMO safety,the regulations have been further,and greatly improved,during improvement stage.From 2021,a few additional revisions have been made,and meanwhile,the new regulation on gene-edited crops was introduced with the development of biotechnology,forming a relative complete regulation and law system for China.The well-developed GMO regulations establishes a firm basis for safe use of GM crops in China.Currently,GM cotton and GM papaya have been widely grown on a large scale in China that have brought great economic and ecological benefits.In addition,12 corn events,3 soybean events,and 2 rice events have also obtained biosafety certification,but presently,these lines have yet to enter commercial production.However,several GM soybean and corn events have entered pilot industrialization,and can soon be expected to be commercially grown in China.In addition to planting,six GM crops,including soybean,corn,cotton,canola,papaya and sugar beet,with a total of 64 events,have been approved for import as processing material in China.展开更多
文摘Establishing an accurate and rapid method for copy number and zygosity determination can accelerate genetic engineering research process. In this study, droplet digital PCR (ddPCR), an emerging DNA absolute quantification technology, was used to identify single-copy homozygous transgenic lines from a batch of T0 transgenic rapeseed harboring 11 exogenous elements. Copy number of exogenous gene was evaluated in T0 generation based on calculated ratio between transgene and reference CruA gene, single-copy transformants were selected for selfing followed by subsequent zygosity analysis. Single-copy homozygous transgenic plants were successfully screened out in T1 generation by ddPCR.Segregation analysis with T2 seedlings verified that identification results of ddPCR were accurate and reliable. This study provides a novel rapid and accurate method for copy number and zygosity determination in transgenic rapeseed which overcomes disadvantages of traditional Southern analysis and recently developed real-time quantitative method.
基金supported by the National Special Biological Breeding Program of the People’s Republic of China.
文摘To ensure safe use of genetically modified organisms(GMOs),since 1993,China has made great efforts to establish and improve the safety regulatory system for GMOs.Here,we summarize and analyze the regulatory framework of agricultural GMOs,and the progress in regulatory approval of GM crops in China.In general,the development of GMO safety regulations underwent four stages:exploration(1993–2000),development(2001–2010),improvement(2011–2020)and current(2021-present)stage.The first formal regulation was promulgated in 1993,which provided a basis for further development of the regulations,during the exploration stage,when insect-resistant GM cotton,expressing genes from Bacillus thuringiensis(Bt),was approved for cultivation.During the development stage,the Chinese government issued a series of administrative measures,which covered almost all the fields relative to GMO safety when the basic regulatory system was established.Along with the controversy over GMO safety,the regulations have been further,and greatly improved,during improvement stage.From 2021,a few additional revisions have been made,and meanwhile,the new regulation on gene-edited crops was introduced with the development of biotechnology,forming a relative complete regulation and law system for China.The well-developed GMO regulations establishes a firm basis for safe use of GM crops in China.Currently,GM cotton and GM papaya have been widely grown on a large scale in China that have brought great economic and ecological benefits.In addition,12 corn events,3 soybean events,and 2 rice events have also obtained biosafety certification,but presently,these lines have yet to enter commercial production.However,several GM soybean and corn events have entered pilot industrialization,and can soon be expected to be commercially grown in China.In addition to planting,six GM crops,including soybean,corn,cotton,canola,papaya and sugar beet,with a total of 64 events,have been approved for import as processing material in China.