My inquiry Question: Should we clone humans?
In my first round of research, I will be looking into what cloning is, the history of cloning, and a few animals that have been cloned!
Firstly, there are three types of cloning!
- Reproductive cloning: Creates copies of an entire animal 
- Gene cloning: Creates copies of segments of DNA or genes 
- Therapeutic cloning: Creates embryonic stem cells which scientists can use for experiments to try and produce tissues to replace diseased or damaged tissues 
For my rounds of research, I will be focusing on reproductive cloning!
What is cloning?
Cloning is a technique used by scientists to create exact genetic copies of living things . In humans, twins are natural clones . Clones contain an identical set of genetic material located in the nucleus which is in the compartment that contains the chromosomes . Cells from two clones have the same DNA and the same genes in the nuclei .
There are two methods of creating living mammal clones and both require implantation of an embryo in a uterus: “Cloning using somatic cell nuclear transfer” and “Cloning by embryo splitting” .
“Cloning using somatic cell nuclear transfer”: 
- FIrstly, you start with the removal of the chromosomes from an egg to create an enucleated egg
- Chromosomes are then replaced with the nucleus taken from a somatic cell of the individual or the embryo to be cloned
- Egg becomes stimulated which means it may start to divide
- If the egg starts to divide, a series of cell divisions leads to form what is called a blastocyst or a preimplantation embryo
- The blastocyst is implanted into the uterus which can result in further development, sometimes resulting in the birth of an animal.
- The animal is a clone to the individual who donated their nucleus. Its nuclear DNA is inherited by only one genetic parent
“Cloning by embryo splitting”: 
- This method of cloning begins with in vitro (in the glass like a test tube, for instance) fertilization
- Outside of the woman’s body, a sperm and an egg will generate a zygote
- It will then divide into two and then into four identical cells at this stage, the cells can start to separate and are allowed to develop identical blastocysts
- These identical blastocysts will then be able to be implanted in a uterus
- However, there is a limited development potential of the cells meaning that the procedure cannot be repeated
- The embryo splitting can only create no more than four humans and only two mice
- The DNA in the embryo splitting is contributed from two individuals who give their germ cells – the mother and father who contributed their egg and sperm.
History of cloning:
In the 1900’s, Hans Spemann observed into blastomeres that dislocated from the early salamander embryos that were developed into normal individuals . Which suggested there was no gene loss at the early stage of development .
In 1901, the cloning method of transferring the nucleus of a salamander embryonic cell to an enucleated cell was a success . John Gurdon did an experiment by using a technique to produce viable frogs by using a nuclear transfer from intestinal epithelium cells . His work demonstrated that cell differentiation takes place without gene loss . As well as if the differentiated cells are exposed to the oocyte’s cytoplasm then cellular commitment may be reversible . During the 1940s to 1950s, scientists were able to clone embryos in mammals . In 1962, a mature frog was produced by transferring the nucleus of intestinal cells of tadpoles into the eggs while their nucleus was removed . Keith Campbell had done experiments and became successful in producing two sheep clones from an embryonic cell line .
In 1996, scientists cloned the first animal, Dolly the sheep . She was cloned by using mammary gland cells that were taken from an adult sheep . Dolly, the sheep’s birth was quite moving because it had proved that the nucleus of the adult cell had all the DNA necessary to give another animal life . Dolly died in 2003 at age six from lung infection which is common in animals who do not go outdoors .
Since Dolly’s birth, scientists have been able to clone cows, cats, rabbits, horses, cats, and dogs! . However, scientists have not been successful in cloning a whole human .
In my second round of research, I will look into the advantages of cloning!
Thank you for reading my first round of research!