Biography 34: Stan Norman Cohen (1935 - )
Stan Cohen was born in Perth Amboy, New Jersey. As a child, he was very interested in science, especially in how things worked. He built and assembled telephones, radios, and thought that he might become a physicist.
He eventually changed his mind and decided he would rather be a medical doctor. After graduating from Rutgers College in 1956, Cohen went to the University of Pennsylvania School of Medicine. He finished his medical degree in 1960.
During his residency, Cohen became more and more interested in basic research. While he was at the National Institutes of Health, he made the decision to combine basic research with clinical medicine. This would be similar to todayâ€™s more formal M.D./Ph.D. programs. He accepted a position at Stanford Universityâ€™s medical school in 1968 and began experimenting with plasmids.
Plasmids have clinical importance because of the drug resistance genes they carry. Leslie Shiu, a graduate student in Cohenâ€™s lab, found that adding calcium chloride increases the chances that plasmid DNA would be incorporated by bacteria. Transformed bacteria would then maintain and propagate the plasmid DNA. Cohen saw the implications; this was a natural Xerox machine for DNA. If DNA could be first introduced into plasmids and then transformed into bacteria, then large quantities of DNA could be produced.
Cohen worked on ways of breaking up the plasmids, and isolating usable fragments for cloning. In 1972, at a meeting in Hawaii, Cohen sat in on a talk by Herbert Boyer, who spoke about how a restriction enzyme, EcoRI, generated sticky ends. Later that night, a group including Boyer and Cohen met up at a deli. Boyer and Cohen discussed various ways they could collaborate. Recombinant DNA technology was born on a deli napkin. Cohen and Boyer eventually patented their technique â€“ one of the first biotech patents granted.
Cohen is a Professor of Genetics at Stanford University. He is a member of the National Academy of Sciences, and in 1980, won the Albert Lasker Basic Medical Research Award. He was awarded the National Medal of Science in 1988. He enjoys skiing, hiking, playing the five-string banjo, and sailing on his boat Genesis.
Herb Boyer and Stan Cohen "invented" recombinant DNA technology.
Stanley Cohen and Herbert Boyer transform bacteria with a recombinant plasmid, and Doug Hanahan studies induced transformation.
Image of Herbert Boyer. From lineman on the varsity football team to co-founder of the first biotech company, Boyer has never lacked imagination, drive, or vision. His and Stanley Cohen's recombinant DNA work paved the way for the biotech revolution.
Stanley Cohen and Herbert Boyer's historic experiment used techniques to cut and paste DNA to create the first custom-made organism containing recombined or "recombinant" DNA.
Herb Boyer talks about Stanley Cohen's and his interest in plasmids as vectors for DNA.
Stanley Cohen and Herbert Boyer inserted the recombinant DNA molecule they created into E. coli bacteria by means of a plasmid, thereby inducing the uptake and expression of a foreign DNA sequence known as "transformation."
Herb Boyer reflects on the importance of their work on rDNA technology and its impact on understanding the genetics of higher organisms.
Herbert Boyer: Former varsity lineman turned biotech bigwig. Expert at cutting DNA before most people knew it could be done. Stanley Cohen: A born tinkerer; figured out the trick of using loops of DNA called plasmids to transform bacterial DNA
Stanley Cohen speaks about his and Herbert Boyer's experiment to make the first plasmid that had been engineered to contain foreign DNA.
Herb Boyer talks about the fateful meeting, which led to the establishment of the first biotech company.