The birth of genetic engineering and recombinant DNA began at Stanford University in 1970 (Huh). Researchers in biochemistry and medicine followed separate paths of research, but these paths converged to form what is known today as biotechnology (Hein). The biochemistry department was, at the time, focusing on an animal virus and found a method to cut the DNA so cleanly that it would reform and infect other cells. (Huh) The medical department focused on bacteria and developed a microscopic molecular messenger, which could not only carry a "plan" or foreign message, but could also cause bacteria to read and copy the information. (Huh) A concept is needed to understand what happened at Stanford: how a bacterial “factory” turns on or off. (Huh) When a cell divides or produces a protein, it uses promoters (“switches on”) to start the process and terminators (“switches off”) to stop the process. (Huh) To form proteins, promoters and terminators are used to indicate where it begins and where it ends. (Huh) In 1972, Herbert Boyer, a biochemist, provided Stanford with a bacterial enzyme called Eco R1. (Huh) This enzyme is used by bacteria to defend themselves against bacteriophages or bacterial viruses. (Huh) The biochemistry department used this enzyme as a "molecular scalpel" to cut a monkey virus called SV40. (Huh) What the Stanford researchers observed was that when they did this, the virus reformed in a circular fashion at the cleaved site. It then infected other cells as if nothing had happened. (Huh) This proved that EcoR1 could cut binding sites on two different DNA strands, which could be combined using the "sticky ends" at the sites. (Eh). The biochemistry department's contribution to genetic engineering was the observation of the cleavage of EcoR1 from