Genetics Timeline

  • Gregor Mendel

    Gregor Mendel
    Gregor Mendel discovered the fundamental principle of genetics; parents pass on traits to children. He found this out by breeding garden peas by cross-fertilization to control their parents; he created 3 generations of peas; P: the parent generation, F1 generation: the children of the P generation, and the F2 generation, which was the children of the F1 generation.
  • William Baetson and Reginald Punnett

    William Baetson and Reginald Punnett
    William Baetson and Reginald Punnett discovered inheritance pattern for genetics and linked genes, also Reginald Punnett originated the Punnett squares. For their expirement, they crossed doubly heterozygous sweet peas and found a pettern of their kids to be 9:3:3:1 for their genetic inheritance, and as they crossed different genetic traits, they found that the ratio changed.
  • Thomas Hunt Morgan

    Thomas Hunt Morgan
    Thomas Hunt Morgan discovered the recombination frequency along with crossing over. He discovered these by crossing fruit flies. He controlled who they mated with so he could know where they came from, he also crossed flies with different color eyes and studied the results of these crossings.
  • Archibald Garrod

    Archibald Garrod
    Archibald found the relationship between genes and proteins. He also figured out that inherited diseases reflects a person's ability to make a particular enzyme. He realized this by hypothesizing that a lack of an enzyme creates diease.
  • Frederick Griffith

    Frederick Griffith
    Frederick Griffith discovered transformation. He found this by doing an experiment involving the bacteria pneumonia. He took a harmful bacteria and inserted it into a rat, and the rat died. Then, he took an harmless bacteria and inserted it into a mouse. The mouse stayed alive. He then took the harmful bacteria and heated it, making it die. When he inserted it into a mouse, it did not die. Finally, he took the heated harmful bacteria and combined it with the harmless bacteria and inserted it
  • Frederick Griffith (contined)

    into a mouse, the mouse died.
  • George Beadle and Edward Tatum

    George Beadle and Edward Tatum
    George Beadle and Edward Tatum found that an individual gene dictates the production of a specific enzyme. They found this out by taking an orange mold and studied its strains.
  • Erwin Chargaff

    Erwin Chargaff
    Erwin Chargraff discovered that in DNA, adenine is the same amount as thymine, and guanine is the same amount as cytosine. So, he figured out that adenine must always pair with thymine, and guanine must always pair with cytosine.
  • Alred Hershey and Martha Chase

    Alred Hershey and Martha Chase discovered that DNA is where the genetic material is found in a cell. They discovered this by doing an experiment involving readiactivity. First, they took radioactive proteins and attach it to a bacteria. They blended it and made it seperate from everything else. Then, they looked to see if the genetic material was radioactive. It was not. So, they did the same with DNA, only in place of proteins was radioactive DNA. They looked to see if the genetic material was
  • Alred Hershey and Martha Chase (continued)

    Alred Hershey and Martha Chase (continued)
    radioactive, and it was.
  • Maurice Wilkins and Rosalind Franklin

    Maurice Wilkins and Rosalind Franklin
    Maurice Wilkins and Rosalind Franklin found that DNA was a helix. They did not find this themselves, but their expirement helped this fact be found greatly. Their experiment was that they took a very clear picture of a DNA, and in the picture, you could see the helix.
  • James Watson and Francis Crick

    James Watson and Francis Crick
    James Watson and Francis Crick found the diameter of a DNA (2 nm) and figured out that DNA is a double helix. They found this by measuring the DNA, and constructing a model of a DNA which resembled the photo that Rosalind Franklin took.
  • Marshall Nirenberg

    Marshall Nirenberg
    Marshall Nirenberg deciphered the first codon. He did this by doing an experiment in which he synthesized an RNA molecule by linking identical RNA nucleotides.