Cloning

By Maddie Arnette

  • First primate created by embryonic cell nuclear transfer

    First primate created by embryonic cell nuclear transfer
    Primates are good models for studying human disorders. Cloning identical primates would decrease the genetic variation of research animals, and therefore the number of animals need in research studies.

  • Nuclear transfer from genetically engineered laboratory cells

    Nuclear transfer from genetically engineered laboratory cells
    Was an exciting combination of findings from earlier work. Campbell and Wilmut had already created a clone using the nucleus of a cultured cell

  • More mammals cloned by somatic cell nuclear transfer

    After the successes leading up to Dolly and Polly, other scientists wanted to see if similar techniques could be used to clone other mammalian species. Before long, several more animals had been successfully cloned. Among them were transgenic animals, clones made from fetal and adult cells, and a male mouse; all previous clones had been female.

  • Endangered animals cloned by somatic cell nuclear transfer

    Scientist began to explore cloning as a way to create animals belonging to endangered or extinct species. A challenge to cloning endangered and extinct species is finding closely related animals to serve as egg donors and surrogates.

  • Primate embryonic stem cells created by somatic cell nuclear transfer

    Took a cell from an adult monkey and fused it with an enucleated egg cell. The embryo was allowed to develop for a time.
    Showed that nuclear transfer in a primate, which researchers had tried for years without success, was possible. It opened the door to the possibility of human therapeutic cloning: creating individual-specific stem cells that could be used to treat or study diseases.

  • First extinct animal

    Using goats as egg donors and surrogates, another group of researchers cloned the first extinct animal, a Spanish mountain goat called the bucardo. Sadly, the one kid that survived gestation died soon after birth due to a lung defect.

  • Human embryonic stem cells created by somatic cell nuclear transfer

    Mitalipov and colleagues were the first to use somatic cell nuclear transfer to create a human embryo that could be used as a source of embryonic stem cells.
    In this experiment, researchers took a skin cell from the patient and fused it with a donated egg cell. Key to the success of the experiment were modifications to the culture liquid in which the procedure was done and to the series of electrical pulses used to stimulate the egg to begin dividing.