Examples Of Genetic Transfer Manipulation

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Humans have been manipulating the natural genetic transfer of animals and plants for a long time. Cloning and selective breeding are well known examples of genetic transfer manipulation. This report will focus on these two manipulations, and the implications they can have on the individuals, and the populations too. In order to show why genetic transfer manipulations are used, and to see the implications of it, the cases of “Dolly” the cloned sheep, and domesticated horses will be used, along with extra examples as further evidence.
Cloning is the creation of a genetically identical copy of something. Although there are examples of naturally occurring cloning, i.e. asexual reproduction that takes place
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In this process, two donors of the same species are selected. Generally the somatic cell donor (the organism to be cloned) has favoured traits that are desirable in the offspring. The other donor is an egg donor, i.e. a female. The egg needs to be in the stage at which fertilization would occur if it was to be fertilized in sexual reproduction. Firstly, the nucleus of the egg cell (which has not been fertilised) is removed using a sharp pipette. This process in known as enucleation. Next, the nucleus of the donated somatic cell is also removed and transferred into the egg cell. For the cell to then begin division (mitosis), chemicals or electric pulse is applied to stimulate development. Once the cells has divided successfully into a blastocyst, an early stage embryo. The embryo is then placed into the womb of the surrogate mother. From here, the embryo should develop as a normal embryo and if successful, the surrogate mother will give birth to a healthy offspring. Once again, the cloned offspring is not genetically related to the surrogate mother, rather genetically identical to that of the somatic cell …show more content…
By specifically selecting organisms with favourable traits, other important qualities may be compromised. This can mean a decrease in genetic biodiversity. Of course, as previously stated, clones are identical copies of the organism from which the embryo or somatic cell was received. If cloning was to be used on a large scale such as in Finn Dorset sheep like Dolly, where the majority/all of the sheep were cloned, although the desired trait (like favourable wool production) may be achieved, the fact that there is essentially no genetic variation over the population of the farm, should the sheep encounter a problem that they are unable to overcome, it’s likely that not just a few, but all of the sheep could be affected, ultimately potentially wiping out the entire population. This highlights the importance of genetic biodiversity within a population, to prevent this kind of situation occurring. It is known that koalas, already in decline, have very little genetic diversity, which could become an issue should a disease or a competition species be introduced into koala populations. With a low genetic diversity, there will be fewer individuals that are able to overcome a crisis like this, meaning fewer survivors, and a smaller population. Over time, numbers of koalas would further decrease, eventually leading to the extinction of the

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