Laboratory Usage
The deliberate exploitation of selective power has become common in experimental biology, particularly in microbiology and genetics. In a ubiquitous laboratory technique in genetic engineering, genes are introduced into cells in cell culture, usually bacteria, on a small circular DNA molecule called a plasmid in a process called transfection. The gene of interest is accompanied on the plasmid by a reporter gene, or "selectable marker", which encodes a specific trait such as antibiotic resistance or ability to grow in high salt concentrations. The cells can then be cultured in an environment that would kill normal cells, but is hospitable to those that have taken up and expressed the genes on the plasmid. In this way expression of the reporter gene serves as a signal that the gene of interest is also being expressed in the cells.
Another technique used in drug development uses an iterative selective process called in vitro selection to evolve aptamers, or nucleic acid fragments capable of binding specific organic compounds with high binding affinity.
Studies in evolutionary physiology, behavioral genetics, and other areas of organismal biology have also made use of deliberate artificial selection, though longer generation times and greater difficulty in breeding can make such projects challenging in vertebrates.
Read more about this topic: Artificial Selection
Famous quotes containing the words laboratory and/or usage:
“The best work of artists in any age is the work of innocence liberated by technical knowledge. The laboratory experiments that led to the theory of pure color equipped the impressionists to paint nature as if it had only just been created.”
—Nancy Hale (b. 1908)
“...Often the accurate answer to a usage question begins, “It depends.” And what it depends on most often is where you are, who you are, who your listeners or readers are, and what your purpose in speaking or writing is.”
—Kenneth G. Wilson (b. 1923)