Timeline

  • Friedrich Miescher

    Friedrich Miescher
    Friedrich Miescher is best known for his incorrect nucleotide hypothesis of DNA. He was 1st to identify DNA as a distinct molecule. This discovery led to many more and was very important. He was born in Basel Switzerland into a well respected family,
  • Frederick Griffith

    Frederick Griffith
    Frederick Griffith performed a famous experiment that proved bacteria can change their function through transformation. He used bacteria infected mice to do this, along with smooth and rough strain. Frederick went to school at Liverpool.
  • Frederick Sanger

    Frederick Sanger
    Sanger was the first person to obtain protein sequence. Sanger proved that proteins were ordered molecules and by analogy, the genes and DNA that make these proteins should have an ordered sequence. After retiring he spent most of his time in his garden.
  • Oswald Avery, Maclyn McCarty, and Colin McCleod

    Oswald Avery, Maclyn McCarty, and Colin McCleod
    First they repeated Griffiths experiment, however they proved it was DNA that is responsible for transformation. They did this by showing it could not be carbs, lipids or proteins responsible for transformation because they tested them all. McCleod wrote a paper explaining bacterial transformation, and went to Mcgill as a med. student.
  • Barbara McClintock

    Barbara McClintock
    McClintock discovered that some genes could be mobile. Her studies of chromosome breakage in maize led her to discover a chromosome-breaking locus that could change its position within a chromosome. She proved that genes are responsible for turning physical characteristics on and off. McClintock never married and devoted her life to research.
  • Erwin Chargaff

    Erwin Chargaff
    Chargaff came up with the idea of base sharing, and later much more information on this was discovered. Base pairing was key part to understanding DNA. He also discovered that there are equal amounts of adenine and thymine; cytosine and guanine. This is known as Chargaff's rule. He also came up with the idea DNA is primarily made up of genes.
  • Rosalind Franklin and Maurice Wilkins

    Rosalind Franklin and Maurice Wilkins
    Franklin and Wilkins worked together to find DNA structure. Franklin worked with X-ray called crystallography and he found DNA was a double helix. The photo they took was called photo 5.
  • Alfred Hershey and Martha Chase

    Alfred Hershey and Martha Chase
    First, Hershey and Chase tagged viral DNA through the use of radioisotopes. They then came up with the idea that DNA can cause problems and viruses. They performed an experiment called the blender and it proved DNA carried genetic information. Later, Hershey received a nobel prize.
  • James Watson & Frances Crick

    James Watson & Frances Crick
    James Watson and Frances Crick built a model of the DNA helix, one with two sugar-phosphate chains running opposite directions, and paired bases inside hydrogen bonds between the internally positioned bases hold the two strands together. Only two kinds of base pairings from A to T and C to G. James Watson and Frances Crick later got the Nobel Prize in physiology or medicine in 1962.
  • Linus Pauling

    Linus Pauling
    Linus was most famous for his discovery of the spiral structure of proteins. This discovery was a big help to figuring out DNA is a double helix structure He used xray results and molecular models in his studies. Linus was awarded the chemistry nobel prize in 1962.
  • Matthew Meselson & Franklin Stahl

    Matthew Meselson & Franklin Stahl
    The experiment performed by Meselson and Stahl demonstrated that DNA replicated semi-conservatively rather than conservatively or dispersive. Semi-conservatively meant that each strand in a DNA molecule serves as a template for synthesis of a new complementary strand. Meselson and Stahl met the summer of 1954, a year after Watson and Crick published their work.
  • Paul Berg

    Paul Berg
    Paul Berg assembled the first DNA molecules that combined genes from different organisms. Berg used multiple methods such as the cut-and-slice method which he created. Paul Berg studied at Penn State for a short amount of time.
  • Kary Mullis

    Kary Mullis
    Mullis discovered the polymerase chain reaction (PCR), a process that allows chemists to produce many copies of a specific fragment of DNA. Before his discovery, he grew up in South Carolina.
  • J.Craig Venter

    J.Craig Venter
    Venter is most notably known for the first human genome published in 2001 and the most recent and most complete sequencing of his diploid human genome in 2007. Venter later won the National Medal of Science in 2008.