Foreign Genes and Gene Products

The soya varieties all contain the same — gene construct. The Gox gene is from Streptomyces and codes for a single protein that inactivates the active compound in glyphosate herbicides. The protein lies behind a CAMV 35S promoter that expresses the gene in all plant tissues at all growth stages. Foreign protein levels in seed are between 8 to 20 ng per g dry weight. This is very low and is undetectable under some growing conditions. The DNA and the protein from the Gox gene are quickly digested in animal digestive juices (10 to 15 seconds) and are rapidly degraded during the heat and shearing processing methods used to produce processed food additives (Table 2). The genes have been stable for 12 growing seasons.

Linear DNA fragment transformed into soya to give RR resistance KEY

P35S = CaMV promoter gox = herbicide-tolerant gene from Streptomyces sp.

nos = nopaline synthase terminator from Agrobacterium sp.

\ = a second insert (93bp) has been detected in RR soya, but has no coding region, produces no protein, and does not alter plant physiology in any detectable manner

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