Gene flow from major genetically modified crops and strategies for containment and mitigation of transgene escape: A review

Recent advancements in biotechnology resulted in rapid adoption of genetically modified (GM) crops in the agriculture systems. At the same time, transgene escape has also been reported and examples reveal global dimension of the problem. Pollen mediated gene flow (PMGF) is the major pathway for transgene escape. Almost all transgenes have been escaped into their Non-GM counterpart and wild relatives. Although gene flow varies between species, crops, and ecological zones/environments but intraspecific gene flow (> 10%) is not uncommon in adjacent populations. Whereas in outcrossing species, 1% gene flow at thousand meters’ isolation is not unusual, and magnitude is even higher than the mutation rate. It is well documented that transgene flow is deteriorating different production systems in agriculture and famers choice to cultivate GM, conventional and organic crops. If comprehensive policy is not implemented, then in future it will be difficult to detect and remove transgenes from the environment; if unexpected problems arise.