This is post no. 1 under the main topic.
| 07-16-2010, 10:01 AM
(This post was last modified: 07-16-2010, 10:25 AM by Administrator.)
What is Cloning?
It is a process by which an identical copy of DNA is produced. It is used to reproduce type specific cells such as an individual organism like Dolly Sheep. Unlike normal reproduction, cloning requires a single parent. A few types of plants have been cloned in the course of many years but cloning of animals especially humans is an ethical issue. Cloning enables illnesses to be cured and to make plants healthier.
Cloning is done by using a circular DNA as a carrier in which a foreign piece of DNA is put. Special genetic information is held within this foreign piece of DNA. The circular DNA is called a vector which acts as a means of transport. The vector then replicates and is then transferred from one living organism to another. This living organism is called a host as its body acts as a temporary home for this DNA and its vector. The new circular DNA with the foreign piece is called a clone which is different from the parental vector.
Nuclear Transfer is a type of cloning that involves transfer of nucleus from a somatic cell (e.g. blood cell, heart cell) to an egg cell. The nucleus of the somatic cell is removed by a micropipette and injected into an enucleated oocyte, which is an unfertilized cell. The nucleus is then given an electric shock so as to fuse with the cytoplasm. It then divides until it becomes an embryo and is then implanted into a surrogate thus giving rise to an identical organism.
Artificial Twinning is also a type of cloning in which an embryo is artificially divided into two or more embryos. An egg is fertilized by sperm. In the early stages of its formation, the embryo is split into two or more embryos which are then left to grow in a surrogate. The offspring thus produced are identical.
Before the birth of Dolly Sheep, an experiment was performed on frog cells. Nucleus from a frog’s gut cell was injected into an enucleated oocyte. The cell began to divide until an embryo was formed thus resulting in tadpoles. Earlier on, this technique only worked on frogs. Scientists could not clone mammals. Another drawback was that the tadpoles never grew into frogs; they died at a very early stage.
After a lot of experimentation, scientists discovered that using a quiescent (undividable) cell instead of a fast dividing cell will prove helpful in cloning of mammals. Therefore they started an experiment on sheep. The method used was Nuclear Transfer. They took a cell from the mammary glands of a Finn Dorset breed of sheep, removed the nucleus and injected it into a Blackface ewe breed. An electric pulse was then used to fuse the nucleus with the cytoplasm of the cell. This fused cell was then transferred into a Blackface ewe. This process was repeated 276 times and after 148 days, Dolly Sheep was born on 5th July 1996. This success enabled scientists to clone domestic animals such as cows, horses, bulls etc. After being bred with a Welsh Mountain ram, Dolly gave birth to six lambs. She then died at the age of six as she developed lung diseases and arthritis.
This is post no. 2 under the main topic.
| 07-17-2010, 03:01 AM
Very nice information Natasha .. Welcome to the forum, hope to see you around more often.
Another way of classify cloning is:
* Recombinant DNA Technology or DNA Cloning
* Reproductive Cloning
* Therapeutic Cloning
This is post no. 3 under the main topic.
| 07-20-2010, 08:29 AM
Thank you very much Charles, i shall be discussing these topics in detail. Thanks for the idea.
This is post no. 4 under the main topic.
| 07-26-2010, 06:24 PM
(This post was last modified: 07-29-2010, 08:58 PM by Biotec.)
Cloning in biology is the process of similar producing populations of genetically identical individuals that occurs in nature when organisms such as bacteria, insects or plants reproduce asexually. Cloning in biotechnology refers to processes used to create copies of DNA fragments, cells, or organisms. The term also refers to the production of multiple copies of a product such as digital media or software.Molecular cloning refers to the process of making multiple copies of a defined DNA sequence. Cloning is frequently used to amplify DNA fragments containing whole genes, but it can also be used to amplify any DNA sequence such as promoters, non-coding sequences and randomly fragmented DNA. It is used in a wide array of biological experiments and practical applications ranging from genetic fingerprinting to large scale protein production
This is post no. 5 under the main topic.
| 10-06-2012, 07:30 PM
When it comes to cloning, the first thing that comes in my mind is parallel universe! Astronomies theories always suggest that there is very similar universe parallel to the one we know and a hypothesis that everything here is replicate of that parallel universe. It means that there is possibility of number of our replicate exactly similar like us somewhere in the space or universe. Cloning is very similar concept and is the subject of biology which produces similar population of individuals which are genetically identical. Cloning is of different types. Molecular cloning is process of making multiple molecules. This method is used for amplification of DNA fragments containing complete gene. Whatever is the type of cloning, the basic pathway to it is common. It involves four common steps. 1) Fragmentation (DNA Breaking)2) Ligation (Joining the DNA pieces in desired sequence)3) Trasnfection (Inserting newly developed piece of DNA into host cell) & 4) Screening (Selecting cells successfully transfected with new molecule of DNA).
Now a day’s new techniques of insertion of interested genome into cells are developed these are electroporation, optical injection and biolistics. Such examples of cloning are Dolly Sheep, Which is a first mammal successfully cloned at Roslin Institute in Scotland, Water Buffalo Philippines (2007) which was first cloned water buffalo. Human cloning is a subject of interest and lot of discussion is going on in the world on this. The American Association for Advancement of Science (AAAS) had suggested the human cloning to be banned until safety issues & ethical concerns are resolved.
This is post no. 6 under the main topic.
| 10-20-2012, 04:16 AM
(This post was last modified: 10-20-2012, 06:18 AM by Administrator.)
I need help with describing the three kinds of cloning. Like human cloning, animal cloning and stem cells. According to their conditions that center schooners can realize; that would be amazing. Do you agree with me?
This is post no. 7 under the main topic.
| 05-27-2013, 04:40 PM
(This post was last modified: 05-31-2013, 01:15 AM by Administrator.)
If you are talking about the human cloning.. So I think it's much simple To understand human cloning. The three types of cloning must be understood. Like I have mentioned at the bottom..
The first is DNA Cloning.
And second Reproductive Cloning.
And the third Therapeutic Cloning.