What do you know about cloning?
In fact cloning is a word with a lot of meanings in biology, and it has been observed at a wide range of living beings starting with the most simple organisms and ending with humans. I will not explain all of the following terms because it will take me a very long time to do it. So we have: -Vegetative reproduction: at flower plants, fungi and lichens, different types of worms, sponges, coelenterates.
-Parthenogenesis: in various kinds of insects, arthropods, reptiles and fishes (some, not all of them).
-Monozygotic twins.
-Immune system- clonal selection mechanism
But humans introduced new meanings to this word and here are some types of artificial cloning:
-Callus - in plants
-Immortalization- cellular lines
-Induced Parthenogenesis- animals
-Recombinant DAN technology- cloned molecules
-Adult cell cloning- plants, animals...
What is in fact a clone?
A clone should be any organism whose genetic information is identical to that of a "mother organism" from which it was created (this is how wiki says it)...
But will a clone really be identical to his "mother organism"? Well in artificial cloning this is very wrong, as the "mother" can only be the carrier organism. You can clone the father or any other living relative (or not- as in not a relative).
So what is a clone? Then it should be an identical genetic copy of an organism. But nothing living can be 100% identical to anything else, because the environment (either internal or external) induces mutations in different places of the genetic make-up. But a clone is the closest thing possible to the 100% identity.
Humans want to use the artificial cloning to bring back to life extinct animals (like the Tasmanian tiger
, or the Mammoth 
or even the Dinosaurs
), or to clone human beings. I must say that the later seems more easy than the first.
Why do i say this ? Well because working with any material from a dead organism is very very hard. At death a lot of complex reactions start to degrade the cells and nucleic acids. Even if the body has been conserved very close to it's death (like freezing for the mammoth or ethanol for the "tiger") the DNA is still broken. In 2008 scientists reported that they managed to restore functionality of a gene Col2A1 enhancer obtained from 100 year-old ethanol-fixed thylacine tissues from museum collections (http://www.plosone.org/article/info:doi%2F10.1371%2Fjournal.pone.0002240 or http://en.wikipedia.org/wiki/Thylacine). But this is only one gene and the specimen is 100 years old, not a few thousands as in the Mammoths case or millions of years as in the Dinosaurs case.
But there is yet another problem. As seen in the case of Dolly and other cloned mice, the new organism will have at it's birth the same age as the donor had. What this means is that the clone will ages faster than it will grow. So if the extinct animal was close to it's natural death, the clone will die even before we'll have the opportunity to see it through it's adult life.And if not, well we'll just be able to see it for a relative short time. And besides that, at our current level of technology, cloning has a very small chance of success. A lot of trials and errors are needed in order to do it once right, and even if you'll succeed once, you'll have to try countless times again for doing it once more.
Even if i said that human cloning seems easier than the cloning of extinct animals, it has a few of more barriers than the first has and most of them are raised by none other than us humans. Most people see a threat in human cloning and because of this research is going very slow. It's an interesting thing to have a fight for a thing that it's not even possible yet. Cloning in general it is, but human cloning has never been proved as possible. For the cloning of each organism are needed particular techniques and protocols that will not work on anything else (the same method used to clone Dolly will not work on mice or humans for example).
(Pic 1 - 5 days old Human normal Blastocyst obtained by IVF
(Pics 2-3
As you can see there are clear morphological differences between pictures 1 and 2+3. These differences will not lead to the creation of a normal embryo.
Human cloning may be divided into two categories: reproductive cloning and therapeutic cloning. In many countries of the world reproductive cloning is banned and therapeutic cloning is also looked in for the same reason.
(http://www.ncsl.org/issuesresearch/health/humancloninglaws/tabid/14284/default.aspx
https://www.policyarchive.org/bitstream/handle/10207/3734/RS21517_20030514.pdf)
Why is reproductive cloning banned ? Well mostly because it's not safe yet for both the mother and the future offspring and because of a lot of moral problems. If everyone would have the right to clone humans for reproductive purposes then couples that are unable to make children or have lost their child due to accident or disease, they could have a child this way. But you could ask why don't have a child by In Vitro Fertilization. That would be a very good question as at this point IVF is more exact and has a lot more chances of success than cloning has. But by cloning you could give birth to a sound child (by cloning the healthy parent).
Unfortunately humans are potentially evil creatures and could use human cloning just for organs (this is something a lot of you out there fear off), and a child born for this purpose would have no real life, or they could use human cloning for Eugenics (something that Hitler wanted to do with his Aryans).
Another moral problem regarding the human clone is about it's identity. What will the clone be in relation to the cloned person? If a woman gives birth to her own clone, will she be her sister or her mother? I for one, don't see any problem in here. The child will be that woman's daughter. And you'll say: But she will look just like her mother? Really? And how do you know that? Or better yet when will she look just like her mother ? If that woman would be, let's say 24 years old when she gave birth to her clone, then her daughter will look "just like her" after 18 years ? hmmm then 18 + 24 = 42 in my book ... and an 18 years old girl will never look the same as a 42 years old woman. They will resemble but they will not be identical. Then you'll say that she is identical from a genetic point of view to her mother. Yes that would be true, but what if they are? Will this mater if you know her personally ? Or if you see either one of them on the street (or even both of them at the same time). Think that it will not mater because by cloning you're not able to clone memories, feelings, habits thought processes, or anything related to the brain. Neuronal connections form with each experience, each moment of life. And noone in this world will pass through the same exact experiences in the same order during their life. And neuronal architecture is no embedded in the genetic code. Else monozygotic twins will think the same and from personal experience i can tell you that it doesn't happen like that.
Another problem that will appear with cloning will be that of human instrumentalization (making the human being an instrument).
To be continued ...
