Genetic engineering is the process of modifying an organism's genetic makeup using recombinant DNA (rDNA) technology. This could imply changing one base pair? (A-T or C-G), deleting an entire region of DNA, or inserting an extra copy of a gene. It could also mean extracting DNA from another organism's genome and combining it with another organism's DNA.
Gene therapy is the genetic engineering or modification of human genes to treat or cure disease. Gene therapies can work by several mechanisms:
Gene therapy and genetic engineering are two closely related concepts that involve modifying organisms' genetic material. The distinction between the two is intention. Gene therapy aims to modify genes in order to correct genetic defect in order to prevent or cure genetic diseases. The goal of genetic engineering, however, is to modify the genes in order to improve the organism's capabilities beyond what is normal, for example in plants, genetic engineering can be carried out to improve specific characteristics of the seed or fruits.
There are several options for making changes to the gene. These include homologous replacement, selective reverse mutation and gene addition. Likewise, a chemical could be used to simply turn off a gene and prevent it from acting.