The History of Cloning

By david.smith

  • First-ever demonstration of artificial embryo twinning

    First-ever demonstration of artificial embryo twinning
    Hans Adolf Edward Dreisch proved that when sea urchin embryonic cells are separated, they can each grow into a complete organism.

  • First Artificial Twinning of a Vertebrate

    First Artificial Twinning of a Vertebrate
    Hans Spemann separated two salamander embryos at a very early age, and they both grew into healthy salamanders. However, he also learned that if they had the embryo had already matured, the twinning would not be successful.

  • Hans Spemann Finds that the Cell Nucleus Controls Embryonic Developement

    Hans Spemann Finds that the Cell Nucleus Controls Embryonic Developement
    Sperrman artificially placed the nucleus from an early embryonic cell into a fertilized egg. The egg grew into a fuctional salamander, thus proving that the nucleus of an embryonic cell is responsible for the complete growth of a salamander.

  • First successful nuclear transfer

    First successful nuclear transfer
    Robert Briggs and Thomas King transferred the nucleus from an early tadpole embryo into a a frog egg whose nucleus they had removed.

  • First mammalian embryo created by nuclear transfer

    First mammalian embryo created by nuclear transfer
    J. Derek Bromhall successfully transferred the first mammal nucleus into a rabbit egg cell, resulting in a functional rabbit.

  • First mammal created by nuclear transfer

    First mammal created by nuclear transfer
    Steen Willadsen placed a fertilized egg into the womb of a female sheep. The sheep gave birth to three live lambs.

  • First cow created by nuclear transfer

    First cow created by nuclear transfer
    Neal First, Randal Prather, and Willard Eyestone perform the same experiment as Steen Willadsen, except on a cow. It works.

  • Dolly: First adult mammal cloned from an adult

    Dolly: First adult mammal cloned from an adult
    Ian Wilmut and Keith Campbell take a nucleus from the udder of an adult sheep and implant it into an egg. The resulting sheep is an exact copy of the original.

  • First primate cloned

    First primate cloned
    Li Meng, John Ely, Richard Stouffer, and Don Wolf clone the first primate. This is majorly important because it decreases the genetic variation in lab animals and shows that primates, and therefore humans, can be cloned.

  • Human embryonic cells cloned

    Human embryonic cells cloned
    Shoukhrat Mitalipov and colleagues cloned human embryonic cells in order to create stem cells for a specific patient.