Rice science’s graduation to gene-editing technology

Bangladesh is the world’s fourth-largest producer of rice, yet the country has to depend on the world grain market to meet the domestic shortfall.

With over 2.5 million tons of imports in the 2020-21 trading year, it emerged as the second-largest importer of the staple after China. 

It’s a clear reflection of a demand-supply gap that Bangladesh is required to bridge by import. 

To cut its import-dependency the country simply cannot afford any further expansion of rice acreage as this single cereal grain already occupies over 70% of Bangladesh’s total arable land, leaving only 30% available for all other crops to compete for ever scarcer farmlands.

Now it occurred to Bangladesh’s rice scientists to pursue frontier science – genome editing (commonly referred to as gene editing) to gain different stress and disease-tolerant traits in quick time thereby, increasing the productivity of some of the existing best rice breeds.

And the scientists at Bangladesh Rice Research Institute (BRRI) have attained early success in developing some of the country’s first-generation gene-edited rice lines, which are expected to effectively fight against diseases like blast, insect-like brown planthopper (BPH) and the climatic stress of high salinity.

Besides, works are also underway to trigger yield potentials of hybrid rice and aromatic rice through applications of gene-editing tool CRISPR/Cas9.

Courtesy: BRRI

Together with the problem of salinity, fungal disease blast and insect BPH, are the key factors holding back Bangladesh from achieving further growth in rice yields.

By applying the CRISPR/Cas9 tool, BRRI scientists have knocked out a few targeted genes from some of its most productive rice varieties in pursuit of gaining new traits, which will effectively fight against blast, BPH and salinity.

CRISPR/Cas9 is a unique technology that enables scientists to edit parts of the genome by removing, adding or altering sections of the DNA sequence.

It is currently the simplest, most versatile and precise method of genetic manipulation and is therefore causing a buzz in the science world. This gene editing tool development earned Emmanuelle Charpentier and Jennifer A Doudna the 2020 Nobel in Chemistry.

Thanks to BRRI scientist Dr Hirendra Nath Barman’s early exposure to then just-developed gene-editing tool CRISPR/Cas9 courtesy his pursuing doctoral degree on this in China (during 2015-2019), he started applying the science in Bangladesh’s homegrown high-yield rice varieties right upon his return from China.

“Now our first-generation gene-edited rice lines are at flowering stage at BRRI greenhouse. We’ll be screening the plants to see whether our expected traits are expressed and will also make sure no off-targeted mutations take place,” Dr Hirendra told Dhaka Tribune.

Hirendra Nath Barman, who works as a senior scientific officer at BRRI’s Plant Physiology Division and holds a PhD in Crop Genetics and Breeding from the Graduate School of Chinese Academy of Agricultural Science (CAAS), spoke of several layers of efficacy and chemical tests before “we can expect of rice with edited traits.”

Courtesy: BRRIFrom his hands-on CRISPR tool application experience at China National Rice Research Institute (CNRRI), Dr Hirendra said Bangladesh might have to wait for at least two to three more years before getting results from the gene-edited lines.

Dr Md Sazzadur Rahman, who works in the same BRRI Division as Hirendra, named specific genes – OsRR22, OsERF922, OsTMS5, OsCYP71A1 and OsBABH2 – which have been targeted for knocking out from different varieties to gain specific advantages of saline-tolerance, disease and insect-resistance and better aroma.

Dr Sazzad, a principal physiologist, also emphasized the need for regulators to come up with regulatory protocols for future crops to be derived through gene editing technology. 

Many experts and scientists told Dhaka Tribune, Bangladesh needs to understand that pursuing a conservative approach, as the country does in the case of GM technology (genetic modification), would be counterproductive if applied in the case of gene-editing technology.

BRRI Director General Shahjahan Kabir said, gene editing tool was applied in some of Bangladesh’s most productive rice varieties i.e., Brridhan-28, Brridhan-63, Brridhan-67, Brridhan-81 and Bangabandhudhan-100.    

He expressed the hope that gene edited rice varietal development would hugely contribute to securing the future food security of Bangladesh.

Powered by Froala Editor