Genetically Modified Organism

Genetically Modified Organism (GMO) a gene codes for a functional protein such as an enzyme which can then produce a metabolite like a glucose molecule. Metabolites, in turn, are responsible for cell function. Many cells together make an organ, and many organs constitute a living organism. Due to variation in the string of nucleotides (made up of sugar, nitrogenous base, and phosphate) that make up a gene, its efficacy in producing the relevant protein may be low or faulty. Scientists can insert a gene with optimal function and create an organism with the altered gene. The organism so produced is genetically modified. So we can have genetically modified bacteria, plants, or animals. The efficient gene has to be delivered within a DNA vector referred to as a recombinant molecule, allowing entry into a single cell. For genetically modified bacteria, the vector with the efficient gene can live inside the bacterial cell. In the case of plants, we usually use a natural vector that can insert the efficient gene into plant genomic DNA and propagate along with plant DNA. In the case of mammalian cells, we sometimes use viral vectors, which help the efficient gene insert into mammalian genomic DNA. Useful examples of GM bacteria can produce the clotting agent called rennet which is used in making cheese, or GM bacteria which produce insulin. An important GM plant of Bangladesh is the BT eggplant, which has a gene that produces a protein called Cry1Ac. This protein is toxic to insect guts but not to humans because of differences in their respective digestive tracts. Therefore, BT eggplant is not destroyed by the FSB insect, which causes intensive damage to eggplants. GM mosquitoes (Aedesaegypti) have been released in several countries to reduce the populations of disease-causing mosquitoes. The GM mosquito males carry a lethal gene, producing a product that will kill the female progenies. The female mosquitoes are the ones that bite and spread dangerous viruses which cause diseases like Zika and Dengue. Recently, blindness was cured by inserting an efficient gene into the human retina. [Zeba Islam Seraj]