The ability of humans to manipulate DNA is a mixed blessing
Genetically modified organisms are made moving the DNA from one species to another. DNA contains genes which code for proteins. For plants and bacteria; restriction enzymes are used to cut a DNA segment from a desired gene source and a bacterium plasmid. They are joined using ligase enzymes and inserted into the plant chromosome or host bacterium. For animals the recombinant DNA is injected into an embryo and transferred to a recipient mother. The organisms will now express a new protein. Proteins determine form and metabolism. Genetic engineering changes the natural DNA of living things, cutting across species boundaries.
Transgene’s effects vary with position. The foreign genes enter the host DNA haphazardly disrupting natural coding. Gene's only replicate faithfully because specialised proteins prevent most errors. Some organisms repair miscoding or have proteins that alternatively splice messenger RNA and thereby produce many different proteins from a single gene. Alien genes and the host's systems will to be unpredictable. In nature a trait is guaranteed by millennia of testing. --------------------------------------------------
Much of the genetic engineering now being used commercially is in the agricultural sector. Plants are genetically engineered to be resistant to herbicides, produce their own pesticides, have viral resistance, and to convert nitrogen directly from the soil. But these transgenes can insert into the genetics of relatives through cross-pollination, creating superweeds resistant to herbicides, pests and viruses. This may increase pest’s immunities and antibiotic resistances, transfer of pathogenic genes, the creation of new viruses, and introduce allergens into the food supply. Worse, these problems will be faster growing, disease resistant, and heat, cold, and drought tolerant. These and mutations may cause irreversible disaster. Planting engineered herbicide resistant...
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