TABLE 1

Chronology of main events relating to development of methods for constructing and cloning recombinant DNAs

YearaEvent
1969–1970P. Berg (1970) and Lobban (1969) independently conceive ideas for generating recombinant DNAs in vitro and using them for cloning, propagating, and expressing genes across species.
1971D. Berg et al. (1974) isolate the first plasmid bacterial cloning vector, λdvgal 120.
1971Concern regarding potential biohazards of cloning first raised by Robert Pollack.
1971–1972Jackson et al. (1972) and Lobban and Kaiser (Lobban 1972; Lobban and Kaiser 1973) concurrently and collaboratively develop the terminal transferase tailing method for joining together DNAs in vitro.
1972Jackson et al. (1972) create first chimeric DNA in vitro.
1972Mertz and Davis (1972) discover that cleavage with EcoRI generates cohesive ends. They use EcoRI plus DNA ligase to generate SV40-λdvgal 120 chimeric DNAs in vitro.
1972–1973Cohen et al. (1972) isolate the drug-selectable bacterial cloning vector, pSC101. They use it to construct, clone, and express bacterial intra- (1973) and interspecies (1974) recombinant DNAs.
1973Morrow et al. (1974) clone and propagate ribosomal DNA genes from a eukaryote in E. coli.
1973–1976Renewed concerns regarding potential biohazards of cloning recombinant DNAs (Singer and Söll 1973; P. Berg et al. 1974, 1975) lead to NIH Guidelines.
1974–1975Filing of initial Stanford University/University of California, San Francisco (UCSF) (Cohen/Boyer) patent applications relating to recombinant DNA.
1976Boyer and Robert Swanson cofound Genentech, the first biotechnology company.
1980Stanford/UCSF (Cohen/Boyer) patent issued by U. S. Patent Office.
  • a Year(s) in which event occurred.