Clonin g By: Gina Patronaggio

Cloning is the creation of an organism that is an exact genetic copy of another! Every single bit of DNA is exactly the same between the two organisms. How does one go about making an exact genetic copy of an organism? There are a few ways to do so: 1. Artificial Embryo Twinning 2. Somatic Cell Nuclear Transfer What is cloning?

Artificial Embryo Twinning These pigs were cloned through the process of Artificial Embryo Twinning. Artificial Embryo Twinning is the relatively low-tech version of cloning. As the name suggests, this technology mimics the natural process of creating identical twins. Artificial embryo twinning uses the same approach, but it occurs in a Petri dish instead of in the mother’s body. This is accomplished by manually separating a very early embryo into individual cells, and then allowing each cell to divide and develop on its own. The resulting embryos are placed into a surrogate mother, where they are carried to term and delivered. Again, since all the embryos came from the same zygote, the are genetically identical.

Somatic Cell Nuclear Transfer (SCNT) Somatic cell nuclear transfer uses a different approach than artificial embryo twinning, but it produces the same result: an exact clone. You must first isolate a somatic cell from an adult female. Next, you transfer the nucleus from that cell to an egg cell from which the nucleus has been removed. After a couple of chemical tweaks, the egg cell, with its new nucleus, will behave just like a freshly fertilized zygote. It develops into an embryo, which is implanted into a surrogate mother, and carried to term.

Somatic Cell Nuclear Transfer (SCNT)

The Pros and Cons of Cloning The Cons of Cloning: 1.High failure rate The Success rate ranges from 0.1% to 3%, which means that for every 1000 tries, only one to 30 clones are made. You can also look at it as 970 to 999 failures in every 1000 tries. 2.Problems during later development Cloned animals that do survive tend to be much bigger at birth than their natural counterparts. Scientists call this “Large Offspring Syndrome” (LOS). Clones with LOS have abnormally large organs. This can lead to difficulties in breathing, blood flow, among other problems

The Pros and Cons of Cloning The Cons of Cloning: 3. Abnormal gene expression patterns Clones look like the originals, and their DNA sequences are identical. However, will the cone express the right genes at the right time? 4. Telomeric differences As cells divide, their chromosomes et shorter. This is because the DNA sequences at both ends of a chromosome, called telomeres, shrink in length every time the DNA is copied. The older the animal is, the shorter its telomeres will be, because the cells have divided so many times. This is a natural art of aging. However, what happens to the clone if its transferred nucleus is already old? Will the shortened telomeres affect its development or lifespan?

The Pros and Cons of Cloning The Pros of Cloning: 1.Cloning for medical purposes a) Cloning animals are models of disease; much of what researches learn about human disease comes from studying animal models. b) Cloning stem cells for research- researchers are currently looking toward cloning as a way to create genetically defined human stem cells for research. c) “Pharming” for drug production- farm animals such as cows, sheep, and goats are currently being genetically engineered to produces drugs or proteins that are useful in medicine. 2. Reviving endangered or extinct species 3. Reproducing a deceased pet 4. Cloning humans a) Why would anyone want to clone humans? Some reasons are: to help infertile couples have children and to replace a deceased child.

The Pros and Cons of Cloning: Problems and Ethical Issues -According to the US Food and Drug Administration, food coming from cloned animals is safe to eat. In addition, the FDA stated that cloned food does not require special labeling. Both meat and milk from cloned animals has no difference from the conventionally bred animals. Joseph Mendelson, legal director of the Center for Food Safety, however, said that cloned food still should be labeled due to the fact that safety and ethical issues of it remain questionable.

The Pros and Cons of Cloning: Problems and Ethical Issues - Recent technological advancements in cloning of animals and potentially human beings has been a highly controversial topic. Some believe it is unethical to use a human clone to save the life of another. The Catholic Church and various traditionalist religious groups oppose all forms of cloning, on the ground that life begins at conception. However, unlike the Catholic Church, Judaism does not equate life with conception. Orthodox rabbis generally have found no firm reason in Jewish law and ethics to object cloning. From the classical liberalism standpoint, concerns exist regarding the protection of the identity of the individual and the right to protect one’s genetic identity.

Where is the technology now? Dolly the Sheep: Dolly is a Finn Dorsett ewe. She was the first mammal to have been successfully cloned from an adult cell, though the first actual thing to be cloned was a tadpole in She was cloned at the Roslin Institute in Scotland, and lived there until her death when she was six. Cloning Dolly the sheep had low success rate per fertilized egg; she was born after 277 eggs were used to create 29 embryos, which only produced three lambs at birth, only one of which lived. However, Dolly is very significant. She shows that genetic material from a specific adult cell, programmed to express only a distinct subset of its genes, could be reprogrammed to grow an entire new organism. Before Dolly, there was no proof for the hypothesis that differentiated animal cells can give rise to entire new organisms. To date, cloned animals include sheep, cattle (5), mice (7), pigs (9), goats (10), cats (11), rabbits (12) rats (14), mules (15), horses (13), and deer (16).

Where is the technology now? Dolly:

Where is the technology now? Despite several highly publicized claims, human cloning still appears to be fiction. There currently is no solid scientific evidence that anyone has cloned human embryos. In 1998, scientists in South Korea claimed to have successfully cloned a human embryo, but said the experiment was interrupted very early when the clone was just a group of four cells. In 2002, Clonaid, part of a religious group that believes humans were created by extraterrestrials, held a news conference to announce the birth of what it claimed to be the first cloned human, a girl named Eve. However, despite repeated requests by the research community and the news media, Clonaid never provided any evidence to confirm the existence of this clone or the other 12 human clones it purportedly created. In 2004, a group led by Woo-Suk Hwang of Seoul National University in South Korea published a paper in the journal Science in which it claimed to have created a cloned human embryo in a test tube. However, an independent scientific committee later found no proof to support the claim and, in January 2006, Science announced that Hwang's paper had been retracted.

Human Cloning is Closer Than You Think!

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