Genetic engineering, also called genetic modification or genetic manipulation, is the direct manipulation of an organism’s genes using biotechnology. It is a set of technologies used to change the genetic makeup of cells, including the transfer of genes within and across species boundaries to produce improved or novel organisms. New DNA is obtained by either isolating and copying the genetic material of interest using recombinant DNA methods or by artificially synthesized the DNA. A construct is usually created and used to insert this DNA into the host organism. The first recombinant DNA molecule was made by Paul Berg in 1972 by combining DNA from the monkey virus SV40 with the lambda virus. As well as inserting genes, the process can be used to remove, or “knock out”, genes. The new DNA can be inserted randomly, or targeted to a specific part of the genome.
HUMAN GENETIC MODIFICATION
Human genetic modification is the direct manipulation of the genome using molecular engineering techniques. Recently developed techniques for modifying genes are often called “gene editing.” Genetic modification can be applied in two very different ways: “somatic genetic modification” and “germline genetic modification.”
Somatic genetic modification adds, cuts, or changes the genes in some of the cells of an existing person, typically to alleviate a medical condition. These gene therapy techniques are approaching clinical practice, but only for a few conditions, and at a very high cost.
Germline genetic modification would change the genes in eggs, sperm, or early embryos. Often referred to as “inheritable genetic modification” or “gene editing for reproduction,” these alterations would appear in every cell of the person who developed from that gamete or embryo, and also in all subsequent generations. Germline modification has not been tried in humans, but it would be, by far, the most consequential type of genetic modification. If used for enhancement purposes, it could open the door to a new market-based form of eugenics. Human germline modification has been prohibited by law in more than 40 countries, and by a binding international treaty of the Council of Europe.