Scientists in Germany and the United States devised a technology that allowed them to ‘cut’ DNA strands and Genome Editing a decade ago.
This approach allows agriculture experts to use site-directed nuclease (SDN) or sequence-specific nuclease (SSN) to make desired alterations in the genome.
Nuclease is an enzyme that cleaves nucleic acid, the genetic material’s building block.
Scientists have developed very effectively clustered regularly interspaced palindromic repeat (CRISPR) -associated proteins-based systems thanks to advanced research. This method enables targeted genomic sequence intervention.
This tool has given plant breeders a lot of new options. Agricultural scientists can now modify the genome to put specific features into the gene sequence using this technique. The process is separated into three categories based on the type of edit that is performed: SDN 1, SDN 2, and SDN 3.
SDN1 makes small insertions and deletions in the host genome’s DNA without introducing any foreign genetic material. In the case of SDN 2, the edit entails generating particular alterations with a tiny DNA template. Both of these procedures do not include alien genetic material, and the end outcome is very identical to conventionally developed crop varieties.
The SDN3 process, on the other hand, utilizes bigger DNA fragments or full-length foreign genes, making it analogous to the formation of genetically modified organisms (GMOs).
Major Difference between genome editing and genome modification
- GMOs (genetically modified organisms) include the insertion of foreign genetic material into the host’s genetic material.
- Soil bacteria are the finest mining source for such genes in agriculture, which are subsequently introduced into the host genome through genetic engineering.
- In the case of cotton, for example, the introduction of genes cry1Ac and cry2Ab from the soil bacterium Bacillus Thuringiensis (BT) allows the native cotton plant to spontaneously produce endotoxins to combat pink bollworm.
- This advantage is used by BT Cotton to assist farmers in organically combating the pink bollworm, which is the most prevalent pest for cotton farmers.
- Genome editing differs from genetic engineering in that the former does not entail the introduction of foreign genetic material, whereas the latter does.
- Both strategies attempt to create variations that are higher-yielding and more resistant to biotic and abiotic stress in agriculture.
- Such variety enhancement was done before the advent of genetic engineering by selective breeding, which involves carefully crossing plants with certain features to produce the desired trait in the progeny.
- Not only has genetic engineering improved the accuracy of this work, but it has also given scientists more control over characteristic development.
What are the regulatory constraints that have kept this approach from becoming more widely used?
- GM crops have been a source of controversy around the world, with many environmentalists rejecting them due to biosafety concerns and inadequate data.
- In India, the introduction of genetically modified crops is a lengthy procedure involving numerous levels of scrutiny.
- The Genetic Engineering Appraisal Committee (GEAC), a high-powered committee under the Ministry of Environment, Forest and Climate Change, is the regulator for the introduction of any GM material, and in the case of agriculture, multiple field trials, biosafety data, and other information are required before any GM crop can be commercially released.
- Bt cotton is the only crop that has managed to get past the regulatory hurdles so far.
- Scientists in India and throughout the world have been quick to distinguish between genetically modified (GM) and genome-edited (GE) crops.
- They have pointed out that the latter has no foreign genetic material, making them indistinguishable from typical hybrids.
- Genome-edited crops and genetically modified crops have been lumped together in the European Union.
- Argentina, Israel, the United States, Canada, and other countries have lax policies for genome-edited crops.
- A group of distinguished agricultural experts wrote to Prime Minister Narendra Modi last year, expressing their displeasure with what they claimed was an effort to push the subject of genome-edited crops on the back burner.
- The federal government had sought input and concerns on the topic from states and union territories at the time, and field experiments with such crops had been halted.
- The signatories, many of whom were Padma recipients, had said explicitly that the SDN1 and SDN2 variations generated do not contain any foreign DNA and may thus be treated as other hybrids.
Way ahead
- By establishing new guidelines, the Environment Ministry put a stop to the debate. SDN 1 and SDN 2 genomes were exempted from the requirement in Wednesday’s notification, and it would instead rely on reports from the Institutional Biosafety Committee to rule out external genetic material.
- Expert committees established under the Act to deal with GM material research and release are known as institutional biosafety committees. These panels would now be tasked with certifying that the genome-edited crop is free of alien DNA.
- For the commercial release of genome-edited crops, this would be a less time-consuming and inconvenient method.
Published by : Aditya Andharia
Edited By : Kritika Kashyap
