Gene-Edited Mustard: Less Pungent, More Useful
Recently Indian scientists have developed mustard with less pungent odor for the first time, which is pest resistant as well as disease resistant.
It is based on CRISPR/Cas9 gene editing while being non-genetically modified (GM) and transgene-free.
Indian mustard seeds are known to have high levels of glucosinolates, a group of sulfur- and nitrogen-containing compounds. It imparts pungent odor to mustard oil and food. Because of this, many consumers avoid consuming such oil.
The low glucosinolate mustards developed by scientists are genome edited or GE, unlike GM or transgenic plants. Glucosinolates are synthesized in the leaves and pod walls of mustard plants. Their transfer and storage in seeds occurs through the action of the ‘glucosinolate transporter (GTR)’ gene.
There are 12 such genes under two distinct clades, GTR1 and GTR2, with six copies each. Researchers have edited 10 out of 12 GTR genes in the high-yielding Indian mustard variety ‘Varuna’.
They used the gene editing tool CRISPR/Cas9 which acts as “molecular scissors” to cut DNA at precise target locations of genes via enzymes.
For gene editing in mustard, the Cas9 enzyme derived from Streptococcus pyogenes bacteria was used to cut the DNA of the target gene in the first generation of plants, the protein being truncated in subsequent generations.
Thus, later mustards do not contain any Cas9 protein and are transgene-free. The research has the potential to increase domestic oilseed production in India, thereby reducing the country’s dependence on imported vegetable oils.
CRISPR technology:
- It is a gene editing technique that uses a special protein called Cas9 to replicate the natural defense mechanisms in bacteria to fight off virus attacks.
- These are usually helpful in adding, removing or altering genetic material through a process described as genetic engineering.
- CRISPR technology does not involve adding any new genes from outside.
Genetic Engineering Appraisal Committee (GEAC)
- Significantly, GM crops currently have to comply with strict “environmental release” regulations in India not only for commercial cultivation but also for field trials and seed production.
- Such a release requires approval from a special Genetic Engineering Appraisal Committee (GEAC) under the Ministry of Environment, Forest and Climate Change.
- It is not binding on the Central Government to accept the recommendation of the GEAC. Thus the final approval rests with the Ministry of Environment, Forest and Climate Change.
Source – Indian Express
