• DNA Replication found semi-conservative

    DNA replication is semi-conservative, as shown by Meselson and Stahl using equilibrium density gradient centrifugation.
  • mRNA

    Messenger RNA is the intermediate between DNA and protein.
  • Genetic Code Cracked

    The genetic code is cracked by a number of researchers (including Nirenberg, Matthaei, Leder, and Khorana) using RNA homopolymer and heteropolymer experiments as well as tRNA labeling experiments.
  • Restriction Enzyme Purified

    The first restriction enzyme is purified by Hamilton Smith.
  • Recombinant DNA Contructed

    Recombinant DNA is first constructed by Cohen and Boyer.
  • DNA Sequencing Technology Developed

    DNA sequencing technology is developed by Fred Sanger.
  • PCR Developed

    PCR is developed by Kary Mullis.
  • Genome Projects Begin

    Genome projects are begun. The yeast genome is complete in 1996, and the C. elegans genome is done in 1998.
  • DNA Microarrays Invented

    DNA microarrays are invented by Pat Brown and colleagues.
  • Small Events

    DNA fingerprinting, gene therapy, and genetically modified foods come onto the scene.
  • Genome Projects Accelerate

    Automated sequencing technology allows genome projects to accelerate.
  • First Clone

    The first cloning of a mammal (Dolly the sheep) is performed by Ian Wilmut and colleagues, from the Roslin institute in Scotland.
  • Genomes Complete

    The Drosophila genome is completed. The Arabidopsis genome is completed. The human genome is reported to be completed.
  • Sequence of Human Genome Released

    The sequence of the human genome is released, and the "post-genomic era" officially begins.
  • Controversy

    Controversies continue over human and animal cloning, research on stem cells, and genetic modification of crops.