gene silencing is the latest technology by which we can suppress that gene which causes harmful effects.
genetic contamination and interbreeding is one possible way to decrease harmful effects, introduced GMOs may interbreed with the wild-type or sexually compatible relatives the novel trait may disappear in wild types unless it confers the selective disadvantage to the recipients, tolerance of wild-type may occur this changes the native species ecological behavior.
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Amanpreet Kaur , Senior research fellow , University Grants Commission, New Delhi
Transgenics have an added benefit of modification as per our requirement but at the same time, there are some ethic and health issues.
One of the best way solution for transgenics in my opinion is that we should try to incorporate gene of plant origin for desired characteristics. For example, to increase osmotin levels in plant, source of gene isolation can be another plant under stress instead of microbial origin.
Secondly, technology like RNAi and CRISPR should be applied for gene knockdown.
Thirdly, if gene is of microbial origin, then care should be taken to express that gene in non edible parts of plant instead of edible parts.