Clones in plant breeding and genetics:
Clones in plant breeding and genetics are usually obtain by the transferring of adult cell nuclei from one organism to oocytes enucleated in another one. cloned mammals were obtained in 1997 by Ian Wilmut with the sheep Dolly. In this specific case the nucleus of an ovum ocyte from a sheep was to eliminated. keeping only of its cytoplasm in which the nucleus of a different somatic cell from a different sheep were introduced later in the case of Dolly from the mammary gland of the dead sheep which had been the frozen.And contrary to what was thought until then (that the nuclei of different cells of the mammals vertebrates organisms in general undergo the irreversible changes during the development) the factors proteins, from which an embryo is originated usually in a third different organism, that is going to develop as a new being dolly in this case.Later, and using this technology all kinds of animals has been cloned cows, bulls, horses, rats cats dog and even macaques. But in the case of humans despite the fact that some cases of cloning have been reported it have not been possible to confirmed their likelihood and many prohibitions.
The clones are SAME BUT DIFFERENT:
The great misunderstanding with clones is to assume they are the genetically identical to be the organisms being cloned and therefore phenotypically identical to them. First we can stress that clones are not completely identical from the genetic point of view to the donors of nuclei. And second that the characteristics of the living beings are not only the result of the genes and despite having a large part of their genes in the common will not same pheonotype display.
The genetic identity between what is being cloned and the clone.They would be identical in terms of DNA nuclei of cell. But they should have different DNA in the mitochondria of their cytoplasm since the clone cytoplasm comes from the egg donor and this donor is different from the mother from which it can be going to be the cloned. This can result in differences in the characteristics and the organs of muscles, heart, brain in which there are greater mitochondrial activity which we know are the factories of the cell energy.
We should be consider that in the process of differentiation of the donor nucleus (something which can initially achieve by culturing the donor cells in the atmosphere) it may happen that the same epigenetic reprogramming was not done in the chromatin one donor had nucleus in methyl groups of the DNA itself an in the modifications of the histone proteins that covered it, in the telomere of the chromosomes.There are a differences which can originate significant differences in the operation of the clone genes with respect to donor.
In addition we can take into the consideration that initial development of early zygotes and embryos is governed by proteins inherited from the egg ovum from cytoplasm, not by the genes of the nucleus. In both cases the cytoplasms of the organism being cloned and the possible clone are the different.
And what is most important in the case of the humans being. The different characteristics of the human beings like attitude depend on the interaction of their genes with the extrauterine environment in which they develod the nutrition, care, education, lifestyle etc.This is where more epigenetic differences especially because they are develop at different time may exist between the organism and its possible clones. See Also: Structure and Function Of Flower
If clones are not identical from the genetic point of view to their “parent” and if their phenotype will almost certainly different, should the prohibitions on reproductive human cloning be reconsidered from the biological point of view? In certain situations of infertility, accidents, diseases, etc., perhaps it should be used once the technical barriersation but on the basis that the clone will not at all be replica exact of the being we can intend to clone and most of a twin physical in appearance but different in other aspects.
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