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Genetic diagnostic technologies are scientific methods that are used to understand and evaluate a person's genes.

Genes are segments of deoxyribonucleic acid (DNA) that contain the code for a specific protein that functions in one or more types of cells in the body.

Genetic diagnostic technology is rapidly improving. Various methods may be used to copy segments of a gene or to find changes in genes.

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Genetic Diagnostic Technologies - Fundamentals - Merck Manuals Consumer Version

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Genetic diagnostic technologies are scientific methods that are used to understand and evaluate a person's genes. Genes are segments of deoxyribonucleic acid (DNA) that contain the code for a specific protein that functions in one or more types of cells in the body. Genetic diagnostic technology is rapidly improving.

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1) Cloning for medical purposes has the potential to benefit large numbers of people.
2.) It is possible to revive endangered or extinct species with future technology
3.) You could clone your family cat for company

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Our experiences have told us that, with a little work, we humans can clone just about anything we want, from frogs to sheep-and probably even ourselves.

So we can clone things. But why would we want to? Below are some of the ways in which cloning might be useful.

Cloning for medical purposes has the potential to benefit large numbers of people. How might cloning be used in medicine?

Cloning animal models of disease

Much of what researchers learn about human disease comes from studying animal models such as mice. Often, animal models are genetically engineered to carry disease-causing mutations in their genes. Creating these transgenic animals is a time-intensive process that requires trial-and-error and several generations of breeding. Cloning could help reduce the time needed to make a transgenic animal model, and the result would be a population of genetically identical animals for study.

Cloning to make stem cells

Stem cells build, maintain, and repair the body throughout our lives. Because these are processes that stem cells do naturally, they can be manipulated to repair damaged or diseased organs and tissues. But stem cells transferred from one person to another (such as in a bone marrow transplant) are seen as foreign, and they usually trigger an immune response.

Some researchers are looking at cloning as a way to create stem cells that are genetically identical to an individual. These cells could then be used for medical purposes, possibly even for growing whole organs. And stem cells cloned from someone with a disease could be grown in culture and studied to help researchers understand the disease and develop treatments.

In 2013, scientists at Oregon Health and Science University were the first to use cloning techniques to successfully create human embryonicstem cells. The donor DNA came from an 8-month-old with a rare genetic disease.

Find out more about Stem Cells.

You might have seen the Jurassic Park movies. In the original feature film, based on the Michael Crichton novel, scientists use DNA preserved for tens of millions of years to clone dinosaurs. They run into trouble, however, when they realize that the cloned creatures were smarter and fiercer than expected. Could we really clone dinosaurs?

In theory? Yes. You would need:

A well-preserved source of DNA from the extinct dinosaur, and

A closely related species, currently living, that could serve as an egg donor and surrogate mother.

In reality? Probably not.

It's extremely unlikely that dinosaur DNA could survive undamaged for such a long time. However, scientists have been working to clone species that became extinct more recently, using DNA from well-preserved tissue samples. A number of projects are underway to clone extinct species, including the wooly mammoth.

In 2009, scientists had their first near-success resurrecting an extinct animal. Using goats as egg donors and surrogates, they made several clones of a wild mountain goat called the bucardo-but the longest-surviving clone died soon after birth. Even if the effort eventually succeeds, the only frozen tissue sample comes from a female, so it will only produce female clones. However, scientists speculate they may beable to remove one X chromossome and add a Y chromosome from a related goat species to make a male.

Cloning endangered species is much easier, mainly because the surviving animals can donate healthy, living cells. In fact, several wild species have been cloned already, including two relatives of cattle called the guar and the banteng, mouflon sheep, deer, bison, and coyotes. However, some experts are skeptical that cloning can help a species recover. One big challenge endangered species face is the loss of genetic diversity, and cloning does nothing to address this problem. When a species has high genetic diversity, there is a better chance that some individuals would have genetic variations that could help them survive an environmental challenge such as an infectious disease. Cloning also does not address the problems that put the species in danger in the first place, such as habitat destruction and hunting. But cloning may be one more tool that conservation scientists can add to their toolbox.

Learn more about Conservation Genetics.

Left: the alpine ibex, a close cousin of the Bucardo. Right: the last remaining Bucardo with the research team before her eventual death. She was blindfolded to shield her eyes from the photographer's flash. Image courtesy of Advanced Cell Technology.

Reproducing a Deceased Pet

If you really wanted to, and if you had enough money, you could clone your beloved family cat. At least one biotechnology company in the United States has offered cat cloning services for the privileged and bereaved. But don't assume that your cloned kitty will be exactly the same as the one you know and love. An individual is a product of more than its genes-the environment plays an important role in shaping personality and many other traits.

On December 22, 2001, a kitten named CC made history as the first cat-and the first domestic pet-ever to be cloned. CC and Rainbow, the donor of CC's genetic material, are pictured at the right.

But do you notice something odd about this picture? If CC is a clone of Rainbow-an exact genetic copy-then why are they different colors?

The answer lies in the X chromosome. In cats, a gene that helps determine coat color resides on this chromosome. Both CC and Rainbow, being females, have two X chromosomes. (Males have one X and one Y chromosome.) Since the two cats have the exact same X chromosomes, they have the same two coat color genes, one specifying black and the other specifying orange.

Very early in her development, each of Rainbow's cells "turned off" oneentire X chromosome, thereby turning off either the black or the orange color gene. This process, called X-inactivation, happens normally in females, in order to prevent them from having twice as much X-chromosome activity as males. It also happens randomly, meaning that different cells turn off different X chromosomes.

So like all female mammals, Rainbow developed as a mosaic. Each cell that underwent X-inactivation gave rise to a patch of cells that had oneor the other coat color gene inactivated. Some patches specified black,other patches specified orange, and still others specified white, due to more complex genetic events. This is how all calico cats, like Rainbow, get their markings.

CC looks different because she was made from a somatic cell from Rainbow in which the X-chromosome with the orange gene had been inactivated; only the black gene was active. What's interesting is that, as CC developed, her cells did not change the inactivation pattern. Therefore, unlike Rainbow, CC developed without any cells that specified orange coat color. The result is CC's black and white tiger-tabby coat.

Left: CC (or Carbon Copy). Right: Rainbow. Photo courtesy TAMU, College of Veterinary Medicine.

Rainbow and CC are living proof that a clone will not look exactly like the donor of its genetic material.

Programs are underway to clone agricultural animals, such as cattle and pigs, that are efficient producers of high-quality milk or meat.

A group of researchers at Utah State University led by Dr. Ken White, Dean of College of Agriculture & Applied Science, have been able to clone steer from slaughterhouse carcasses. Their aim isn't to produce animals for consumption-cloning is far more labor-intensive and expensive than conventional breeding methods. Instead, they want to use these animals as breeding stock.

The important thing to know about beef cattle is that the quality and yield of their meat can be assessed only after they are slaughtered. And male animals are routinely neutered when they're a few days old. That is, their testes are removed, so they are unable to make sperm. But cells from a high-quality carcass can be cloned, giving rise to an animal that is able, though conventional breeding methods, to pass its superior genes to its offspring.

Scientists have also cloned mules, a reproductively sterile hybrid of a male donkey and a female horse; dairy cows; and horses. One gelded racing horse, a male whose testes have been removed, has a clone that is available for breeding. Some of the cloned cows produce about twice as much milk as the average producer. And a cloned racing mule is ranked among the best in the world.

Farm animals such as cows, sheep, and goats are being genetically engineered to produce drugs or proteins that are useful in medicine. As an example, scientists could take cells from a cow that produces large amounts of milk and grow them in culture. Then they could insert a gene into the DNA of these cells that codes for a drug or a vaccine. If they take the nucleus from one of these cells and transfer it to a cow egg, it could develop into a cow that makes the drug in its milk. Since every cell in the cow would carry the drug gene, it could pass the gene to its offspring, creating a whole herd of drug-producing cows. Even better, we could avoid the issue of the genetic reshuffling that happensduring sexual reproduction and simply clone our drug-producing cow.

The prospect of cloning humans is highly controversial, and it raises a number of ethical, legal, and social challenges that need to be considered.

The vast majority of scientists and lawmakers view human reproductive cloning-cloning for the purpose of making a human baby-immoral. Supporters see it as a possible solution to infertility problems. Some even imagine making clones of geniuses, whose work could advance society. Far-fetched views describe farms filled with clones whose organs are harvested for transplantation-a truly horrific idea.

For now, risks and technical challenges-as well as laws that make it illegal-will probably keep human reproductive cloning from becoming a reality. Even though many species have been cloned successfully, theprocess is still technically difficult and inefficient. The success rate in cloning is quite low: most embryos fail to develop, and many pregnancies end in miscarriage.

Current efforts at human cloning are focused on creating embryonic stem cells for research and medicine, as described above. However, many feel that this type of therapeutic cloning comes dangerously close to human reproductive cloning. And once techniques become more streamlined and efficient, they fear that some may be tempted to take that next step.

From a technical and moral standpoint, before human cloning becomes routine, we need to have a good idea of the risks involved.

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Our experiences have told us that, with a little work, we humans can clone just about anything we want, from frogs to sheep-and probably even ourselves. So we can clone things. But why would we want to? Below are some of the ways in which cloning might be useful.

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Overview: DNA cloning (article) | Khan Academy

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Definition, purpose, and basic steps of DNA cloning.

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Gene cloning is done by placing DNA into self-producing molecules such as bacteria, yeasts, viruses, and plasmids. Reproductive cloning takes a mature somatic cell from the animal being cloned and puts it into a separate egg, then implanted into a mothers womb when it has reached the right stage. Therapeutic cloning is done by harvesting stem cells from embryos.

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Gene technology is improving. PCR is a laboratory technique that makes copies of genes. Various methods are used for the different types of cloning: oligonucleotide, probes, microchips to identify DNA mutations

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Genetic diagnostic technologies are scientific methods that are used to understand and evaluate a person's genes.

Genes are segments of deoxyribonucleic acid (DNA) that contain the code for a specific protein that functions in one or more types of cells in the body.

Genetic diagnostic technology is rapidly improving. Various methods may be used to copy segments of a gene or to find changes in genes.

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Genetic Diagnostic Technologies - Fundamentals - Merck Manuals Consumer Version

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Genetic diagnostic technologies are scientific methods that are used to understand and evaluate a person's genes. Genes are segments of deoxyribonucleic acid (DNA) that contain the code for a specific protein that functions in one or more types of cells in the body. Genetic diagnostic technology is rapidly improving.

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Many scientists used and developed different ways to separate embryos and their cells (tiny nooses, nuclear transfers, an in vitro fertilization). Specific scientists discoveries, years and how they did it explained.

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Mice, cows, and goats
Multiple groups
After the successes leading up to Dolly and Polly, other scientists wanted to see if similar techniques could be used to clone other mammalian species. Before long, several more animals had been successfully cloned. Among them were transgenic animals, clones made from fetal and adult cells, and a male mouse; all previous clones had been female.

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Multiple groups After the successes leading up to Dolly and Polly, other scientists wanted to see if similar techniques could be used to clone other mammalian species. Before long, several more animals had been successfully cloned. Among them were transgenic animals, clones made from fetal and adult cells, and a male mouse; all previous clones had been female.

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This discovery can lead to future human cloning. Human cloning carries dangers including rise to medical issues, gene age retainment, and social issues.

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Some folks consider human cloning as the biggest breakthrough of the century, while others consider it as a living nightmare. As such, human cloning means creating an identical human being with the aid of recent technology and genes of the donor. While the cloned individual will look like a carbon copy of the donor in terms of appearance, the personality of the two individuals could be world-apart from each other.

While outward appearance can be cloned, the personality of an individual cannot be cloned. After all, every person out there builds a unique personality for himself based on real life experiences and knowledge gained with growing age. It's believed that the potential dangers linked with human cloning outweigh the advantages associated with human cloning, which is why human cloning is banned in most countries out there. Let's have a look at the potential dangers of human cloning.
Medical Issues
Human cloning can give rise to certain medical issues. Technically, human gene grows older with age. It's feared that the cloned individual would retain the age of the donor's genes. Imagine what will happen if a 40 year old gene is manifested into a newborn baby.
Social Hiccups
There is a possibility that cloned individuals might not receive their due share of respect and acceptance in the society. It's believed that there will be unsettled opinions about the rights granted to a clone. Also, the real beauty of humanity lies in the differences we witness amongst each other. Cloning would kill the surprise element over here.
Health Concerns
The health risks involved with human cloning is something that cannot be sidelined on all accounts. There is a possibility that the cloned individual might carry certain abnormalities, and may die sooner than the standard life expectancy.
Moral Issues
Technological abuse is one aspect that can come into the picture once human cloning becomes a prominent feature. Imagine what a corrupt guy will do after cloning himself. There will always be someone or the other who will try to abuse this technological advancement to the extreme. In some cases, the clone might also turn out to be better than the donor.

Since a clone can conduct almost every activity an average individual can perform such as eating, drinking, bathing etc, it won't come as surprise to learn that human clones will be illegally traded for personal gains. Needless to say, trade of human beings is illegal and against all morals.
Ethical Concerns
Ethical concerns will also be raised on human cloning. There will be loads of protest from various groups, if human cloning is to be legalized in the near future. The whole idea of human cloning is already hurting the sentiments of truckloads of people out there. Some believe that human cloning is playing around with God's rules. The million dollar question that really needs our attention is whether we can create a human being at our will and wish?
Legal Issues
Human cloning laws are said to be very complicated in nature, and they vary from one country to another. The fact that the laws are divided on such a sensitive issue is a certain feature of potential trouble. There have been decent attempts made in the past to pass federal law to ban human cloning completely, but there is no definite law passed as yet that bans all human cloning.

As such, the twentieth century hasn't seen much progress on human cloning as one might have expected, considering the fact that the technological advancement has seen robust growth in the last few decade or so.

Considering all the above said disadvantages linked with human cloning, one can only be happy that the development of human cloning has not seen the day of light as yet. The first mammalian clone was a sheep called Dolly. Although the successful cloning of Dolly was a significant step in this matter, Dolly died young due to a rare disease, which is usually not seen in the sheep of her age group.

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Some folks consider human cloning as the biggest breakthrough of the century, while others consider it as a living nightmare. As such, human cloning means creating an identical human being with the aid of recent technology and genes of the donor.

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Cloning Technology (Future Cloning) - SV

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Cloning Technology (Future Cloning) - SV

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Human cloning differs around the world. In the US it is only outlawed in 8 states. Future of cloning will lie more on therapeutic cloning that reproductive cloning. Future cloning will be about creating transplantable tissue.

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While the ethics and legality of human cloning are blurry, the science behind the idea is quite clear, with all research suggesting the practice is possible. Scientists have already cloned human embryos and many believe creating fully developed humans is the next step. But while novels such as A Brave New World and Cloud Atlas depict human cloning as systematic and as easy as a car part assembly line, in reality the process is a bit more complex.

Cloning in A Nutshell

Cloning describes a number of processes used to create genetically identical copies of a biological entity. Although these processes can occur naturally, such as in some plants and bacteria, the cloning that most likely comes to mind when you hear the word is artificially copying a whole animal.

According to the National Institutes of Health, for this type of cloning, also known as reproductive cloning, scientists remove a mature somatic cell (any type of cell, except a sperm or egg cell) from the animal the scientists wish to copy. The desired DNA is then transferred into an egg of the same species that has had its own DNA removed.

Cloning takes the randomness out of sexual reproduction. Most living things on Earth get half of their DNA from their mother and half from their father, giving them an endless number of genetic probabilities to create their own unique DNA. In cloning, DNA only comes from one organism, which takes the game of chance out of the reproduction and gives offspring an exact copy of the original DNA.

The cloned egg is then allowed to mature into an early embryotic stage before it is injected back into the womb of an adult female animal for gestation. Upon birth, the newborn animal is officially known as a clone.

Seems simple enough, right? Cloning animals is not new science, with the first animal, a tadpole, being cloned in 1952. In 1996, Dolly the sheep became the first mammal to have been successfully cloned born. According to the University of Utah, to date scientists have cloned even more animals, including mice, cows, and goats.

Cloning is also an important practice in other facets of science, although not to the same degree as reproductive cloning. For example, therapeutic cloning, that is cloning embryonic stem cells for testing is a regular practice with the goal of creating not a whole being but rather replacing damaged tissue. In a 2014 study, scientists were able to clone adult stem cells, a huge breakthrough for therapeutic cloning research.

We Can Do It, But Is It Safe?

It would be theoretically possible to clone humans, but, to date, there are no records of an actual fully developed human ever being cloned, Live Science reported. The closest we have come to this is the 1997 cloning of our closet relative: the monkey. Scientists have also succeeded in creating human clone embryos from the skin cells of both infants and full grown adults. However, none of these embryos were ever allowed to mature fully.

Despite scientists being capable of cloning humans, it is still highly unlikely that procedure will even come to be due to ethical reasons. For example, cloning has an extremely high failure rate, with only about one out of 100 cloning attempts ending in a viable animal. Also, reported by Live Science, currently cloned animals also experience poor health. Many are born with abnormally large organs and as a result they often die early or need to be euthanized. For these reasons, many scientists are opposed to even conducting research into the highly controversial subject.

"It's like sending your baby up in a rocket knowing there's a 50-50 chance it's going to blow up. It's grossly unethical," Dr. Robert Lanza, chief scientific officer at the biotech company Advanced Cell Technology, which works on cell therapies for human diseases and has cloned animals, told Live Science.

Future Cloning

The legalities on human cloning differ around the world. In the U.S., human cloning is only explicitly outlawed in eight states. According to the Bioethics Defense Fund, an additional four states simply prohibit state funding of human cloning and 10 states allow human embryos to be cloned but ban the embryo from being allowed to mature full term (thus outlawing reproductive cloning but allowing therapeutic cloning). The international stance on cloning is clearer, with the United Nations General Assembly banning all forms of human cloning in 2005, including both reproductive and therapeutic.

For these legal reasons as well as ethical reasons, it's probable that the future of cloning will lie more in therapeutic cloning research than reproductive cloning. The only difference between therapeutic cloning and reproductive cloning is that in therapeutic cloning the embryo is never transferred into a female's womb. The current goals for therapeutic cloning are a means to develop both patient and disease specific therapies for certain conditions. The procedure could also potentially use a patient's own cells for tissue replacement. Although the science is exciting, it will likely take many decades of research before scientists are able to create transplantable tissue.

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Human Cloning: Just Because We Haven't Doesn't Mean We Can't

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While the ethics and legality of human cloning are blurry, the science behind the idea is quite clear, with all research suggesting the practice is possible. Scientists have already cloned human embryos and many believe creating fully developed humans is the next step.

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Cloning causes major controversy. The idea of human cloning brings up the question of whether it devalues life by changing the original cells that will change the overall human later in life. On the other hand, people take into consideration the medical benefits and possible life saving uses of cloning technology. There have also been arguments as to the fact that is unethical to some religions.

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by Francisco Galdos

Suppose you have a year-old laptop that has been working well for you. You begin to notice one day that the computer freezes more frequently, and you continue to have problems. After taking your computer to the engineers, the engineers discover that a few of the small components of the motherboard are faulty, so they decide to replace it. Sounds simple doesn't it? If we compare the act of replacing a computer part with the feat of replacing a faulty organ in our bodies, we can greatly appreciate the idea of interchangeable parts. Imagine, for example, that someone is born with a defective heart and has had so many surgeries that all that is left is a stiff and scarred heart. If we equate the body to a laptop we could say, "why not replace the organ with a new one?" Why not produce healthy clones of our organs so that we can just replace them when they are defective?

Although a simple idea, scientists and physicians have struggled for more than 50 years to understand how we can manipulate our cells in order to replace or regenerate our bodies. As scientists continue to advance techniques in cloning technologies, we have seen an increase in the number of ethical debates on the future of cloning. Cloning, albeit a straightforward solution to generating new organs, has become taboo in itself, causing the path to duplication to become less linear and more complicated for the scientist. If we would like to see medicine reach an era of curative intervention rather than palliative treatment, it becomes necessary more than ever to fully understand the fundamental scientific questions that cloning has sought to answer. As we look into the history and science of cloning, we find that it reveals a remarkable flexibility in our biology that could allow us to repair many of the problems that often lead to death.

Cloning: A Background

To find the origins of cloning, we need to go back to the 1950s. Embryologists had long been grappling with understanding how the vast diversity of cells in the body could be derived from a single fertilized egg cell. Scientists were puzzled by the concept of cellular differentiation, the ability of a fertilized egg cell to become a unique cell type within the body [1]. Up to this point in history, all that scientists knew was that within the nucleus of a cell there was genetic information, and this nucleus was bathed within the surrounding fluid in the cell, known as the cytoplasm. In order to investigate cellular differentiation, two scientists, Robert Briggs and Thomas King, sought to answer whether there was some type of irreversible change that occurred in the nucleus of the cell, which caused cells early in development to differentiate into the vast array of specialized cells in our tissues and bodies. They pioneered a laboratory technique known as somatic cell nuclear transfer (SCNT)[1]. SCNT involved taking the nucleus of a frog cell that they deemed to be further along in differentiation, and transferring the nucleus into a frog egg cell that had had its nucleus removed. Briggs and King hypothesized that a differentiated cell nucleus that has undergone irreversible genetic changes should have a decreased potential to develop into other cell types, since it would be lacking the genetic information needed to differentiate into all the cells of the body of an animal. Many scientists shared this hypothesis, as well as the idea that some factors within the cytoplasm cause irreversible changes to the genetic material in the nuclei of cells. In 1962, however, a graduate student by the name of John Gurdon conducted SCNT experiments in which he took differentiated frog intestinal cells and transferred their nuclei into enucleated egg cells. Gurdon modified his experimental procedure to conduct serial nuclear transplantations in which he took the already transplanted nuclei, and transplanted them again. In 1966, Gurdon demonstrated that he could effectively obtain adult frog clones with this method [2]. He proposed that if a differentiated cell nucleus could be used to form all the tissues of an entire animal, then the nucleus of a differentiated cell must not have undergone irreversible changes during cellular differentiation [2].

Gurdon's frog experiment represents the first time in history that anyone had effectively cloned an animal, and also the first time that anyone had experimentally shown that during differentiation, cells do not undergo irreversible genetic changes. In a time when the secrets of molecular genetics were still being experimentally discovered, Gurdon proposed that it was through some type of mechanism that genes were turned on and off rather than lost as the embryo began to differentiate [2]. The idea that you could take a fully mature cell and reprogram it to become a cell capable of becoming any cell in the body led to the coining of the term pluripotency, which is the idea that a cell can become any cell in the body. His idea that all cells in the body maintain the same genome and have the potential to be reprogrammed into pluripotent cells inspired efforts to discover new ways to reprogram cells. To start, scientists began by studying the pluripotent cells-the embryonic stem cells. In 1998 James Thompson derived the first human embryonic stem cells [3]. By deriving these cells, scientists such as Thompson were interested in discovering the various genetic factors responsible for maintaining the pluripotent state. Theoretically, if pluripotent stem cells, i.e. embryonic stem cells, could be derived from a patient's cells, such as a skin cell, scientists and physicians could use the pluripotent cells to make replacement tissues that are derived from the patient's own cells.

In 1996, Ian Wilmut effectively derived the first embryonic stem cells using SCNT in a mammal and effectively cloned the first mammal-Dolly the sheep [4]. This lead to widespread fear and resistance that SCNT could be used to clone human beings, and that embryonic stem cells destroyed human life in the process of their derivation. Such fears lead to an 8 year national ban on the use of federal funds for the creation of new embryonic stem cell lines during the Bush administration, which caused massive funding problems for the field of regenerative medicine [5]. Because human embryonic stem cells are both expensive to derive, and ethically controversial to use, they became incredibly inefficient to use for therapeutic purposes. Moreover, as a clinical application, reprogramming was in its infancy since at the time, derivation of human pluripotent stem cells through SCNT had not been done. It was not until 2006 that Shinya Yamanaka and Kazutoshi Takahashi demonstrated the derivation of mouse pluripotent stem cells using the over-expression of four transcription factors [6]. This paper revolutionized the field of cellular reprogramming because it provided an effective alternative to deriving cells equivalent to embryonic stem cells. This effectively took the place of SCNT as a reprogramming technology, as it was accepted as a less controversial form of deriving pluripotent stem cells. SCNT was deemed as controversial because it generates embryos whose embryonic stem cells are then harvested to generate pluripotent cells in a dish. Yamanka's method bypassed the need to generate the embryo and developed pluripotent embryonic-like stem cells directly from a differentiated cell in the body. Indeed, Yamanaka's induced pluripotent stem cells (iPSCs) have been derived from human cells and have been used for a variety of purposes. Despite the shift to Yamanaka's technology, this year, a group of US researchers in Oregon successfully derived the first human embryonic stem cell lines using SCNT, both reviving the scientific discussion of reprogramming and the controversy over human cloning [7]. Looking back, in more than a half-century of research, reprogramming experiments have demonstrated the remarkable flexibility of our cells to be converted into different cell types that can serve as the basis for regenerative therapies.

Therapeutic Hope, The Promise of Cloning

As we saw with the engineer replacing a laptop's motherboard, we can now see how cloning technologies could be used to achieve such "replacements" in our bodies. Cells, it turns out, can be thought about as computers. The DNA of our cells can be thought of as the motherboard of a computer in that DNA essentially controls all the functions of the machine, our cells. The motherboard controls the entire computer's functions depending on how it is programmed. Similarly, cells also depend upon how the DNA is programmed to express certain genes that carry out a particular function. Knowing this, we can then try to drive stem cells such as pluripotent stem cells to differentiate into a cell type that we are interested in obtaining. Take for example, a heart attack patient. During a heart attack, the heart muscle often dies off, causing irreplaceable damage in the heart that often puts patients on heart transplant lists [8]. Making heart cells from pluripotent stem cells would allow us to regenerate the damaged heart.

Regenerative technologies do not solely depend upon the generation of pluripotent stem cells. Scientists such as Doug Melton have sought to explore the possibility of bypassing the pluripotent state altogether and directly reprogram one cell type to another. Melton and coworkers showed that a type of cell known as an exocrine cell, located in the pancreas, could be directly reprogrammed into an insulin producing ß-cell by expressing transcription factors that are only present in ß-cells. If Melton's group can one day make fully mature and functional ß-cells, these cells could effectively be engineered in such a way that they can be transplanted into the pancreas of a patient with type 1 diabetes, which could in theory cure the patient's diabetes.

The fundamental promise of cloning is that scientists can take a person's own cells and manipulate the biology of these cells to regenerate injured or diseased tissues. Using Yamanaka's induced pluripotent cell (iPS) technology, it is even possible to take cells that may have genetic defects, such as defective genes, and genetically engineer the iPS cells derived from a patient such that the defective gene is replaced with the correct gene [8]. For example, consider a patient with muscular dystrophy who has a mutation in the gene called dystrophin. Using iPS technology, we could theoretically take skin cells, make iPS cells, replace the defective dystrophin gene with the correct gene, and make muscle tissue that could be transplanted into the patient to effectively cure his muscular dystrophy [9]. In addition to fixing genetic defects, scientists and physicians such as Harald Ott at the Harvard Stem Cell Institute are pioneering new technologies in what is known as whole-organ assembly [10]. The idea of whole-organ assembly consists of using iPS cells to seed tissue scaffolds that can be assembled to create on-demand replacement organs for patients [10]. Such technology could one day provide patients with fully functional replacement organs made from their own cells.

Breaking Down the Controversy

Despite the incredible promise of these technologies, they continue to find opposition from groups that argue that the use of embryonic stem cells and cloning of human cells into embryonic stem cells devalue human life, and could potentially give rise to the cloning of human beings [11]. The controversy is fueled by questions of right to life and individual determinism [12]. The fact that embryonic stem cells (ESCs) have the potential to give rise to all the cells in the body, and theoretically give rise to human beings, creates vast opposition based on fears that human lives are essentially being killed through the use or creation of these cells [14].

When John Gurdon cloned the first animal, the scientific question he sought to answer was whether cells have some irreversible change in their nuclei as they differentiate. Today, scientists are taking this question a step further towards understanding the molecular and cellular biology of how pluripotent cells undergo cellular differentiation. The Oregon study, which developed SCNT reprogramming of human cells, will serve as a vital study for modifying iPS technologies to make reprogramming more effective, and to remove the inefficiencies of genetic reprogramming that we often see with iPS technologies compared to SCNT [7].

Induced pluripotent stem cells were hailed as ethically acceptable because they bypass the need to use human eggs and human embryos. Although the goal of iPSCs is to replace embryonic stem cells as a away to avoid using human embryos, iPSCs contain many genetic differences that currently make them unsuitable to use for therapeutic purposes [8]. The golden standard for deriving pluripotent cells is in fact an embryonic stem cell derived from an embryo that has been made from the fertilization of an egg. If we are to work out the kinks in the iPS system, the use of embryonic stem cells will be key for making iPSCs suitable for clinical use. Thus, if the controversy arises due to the creation of embryonic stem cells, the following question arises: if we are to perfect iPS technology to effectively derive pluripotent cells that are equivalent to ES cells, should iPS cells be banned as well since our golden standard of comparison must be derived from human blastocysts that have the potential to become a human individual?

If a human life is defined from the moment that a cell has the potential to become a human being (i.e. conception), we find ourselves in an ethical conundrum when thinking about our genome as a whole. We know that all differentiated cells are equivalent in their genomes' potential to become any cell in our bodies, and to also generate an entirely new adult, as we saw with Gurdon's frogs and Wilmut's sheep. Thus, does this indicate that all cells in the body have the potential to form a life and therefore should be considered as such? The beauty of John Gurdon's, Ian Wilmut's, the Oregon Group's, and Yamanaka's experiments are not that they derived a Brave New World type of technology to institute human cloning, but rather they reveal the inherent flexibility of our biology. If we define life from the moment we make a cell that has the potential to produce an entire individual, then we potentially must begin to categorize everything in our bodies by their own inherent potential to form an individual. It becomes incredibly difficult to make these categorizations. Unfortunately, the biology of our cells cannot be so clearly confined with these strict definitions. We are constantly learning that cells are dynamic systems. One way we could think about the flexibility of our cells is that engineering them for medicine capitalizes on this inherent biological flexibility. We should also keep in mind that when developing an ethical position, we should remember both the incredible life saving potential of these cloning technologies, as well as the historical scientific questions that they have answered.

Towards the Future

Cloning technologies have the potential to drive medicine into an era of regeneration. If we define human life as beginning when a cell has the potential to become a full human being, then we may run into difficulties when we consider that essentially any cell in our bodies has the potential to become a full human being. Many ethical arguments against cloning technologies and embryonic stem cell research argue that doing such research inherently destroys human life. We cannot dismiss these arguments, as they propose a valid question, that is-how do we define a human life? Ideally, for the benefit of both scientists and society, we would set ethical boundaries that would allow cloning technologies to benefit humanity in the best possible way.
Acknowledgements:
I'd like to thank my editor Jennifer Guidera for all of her help and feedback during the writing process.

References

1. Briggs, R. and T. King, Transplantation of Living Nuclei From Blastula Cells into Enucleated Frogs' Eggs. Proceedings of the National Academy of Sciences of the United States of America, 1952. 38(5): p. 455-463.

2. Gurdon, J. and V. Uehlinger, "Fertile" intestine nuclei. Nature, 1966. 210(5042): p. 1240-1241.

3. Thomson, J., et al., Embryonic stem cell lines derived from human blastocysts. Science (New York, N.Y.), 1998. 282(5391): p. 1145-1147.

4. Campbell, K., et al., Sheep cloned by nuclear transfer from a cultured cell line. Nature, 1996. 380(6569): p. 64-66.

5. Stolberg, S.G., Bush Vetoes Measure on Stem Cell Research, in The New York Times. 2007. p. A21.

6. Takahashi, K. and S. Yamanaka, Induction of pluripotent stem cells from mouse embryonic and adult fibroblast cultures by defined factors. Cell, 2006. 126(4): p. 663-676.

7. Tachibana, M., et al., Human embryonic stem cells derived by somatic cell nuclear transfer. Cell, 2013. 153(6): p. 1228-1238.

8. Takahashi, K. and S. Yamanaka, Induced pluripotent stem cells in medicine and biology. Development (Cambridge, England), 2013. 140(12): p. 2457-2461.

9. O'Connor, T. and R. Crystal, Genetic medicines: treatment strategies for hereditary disorders. Nature reviews. Genetics, 2006. 7(4): p. 261-276.

10. Soto-Gutierrez, A., et al., Perspectives on whole-organ assembly: moving toward transplantation on demand. The Journal of clinical investigation, 2012. 122(11): p. 3817-3823.

11. Pollack, A., Cloning Is Used to Create Embryonic Stem Cells, in The New York Times. 2013.

12. Franklin, S., Stem Cells R US: Emergent Life Forms and the Global Biological, in Global Assemblages: Technology, Politics, and Ethics as Anthropological Problems. 2005, Blackwell Publishing Ltd.

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Human Cloning: Unmasking the Controversy

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by Francisco GaldosSuppose you have a year-old laptop that has been working well for you. You begin to notice one day that the computer freezes more frequently, and you continue to have problems. After taking your computer to the engineers, the engineers discover that a few of the small components of the motherboard are faulty,...

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A clone is a genetically identical copy of an organism that can be created naturally or in a lab. The three types of cloning are, gene cloning, reproductive cloning, and therapeutic cloning.

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Cloning
A clone is a genetically identical copy of an organism, and it may be naturally occurring or created in the lab. Through the process of asexual reproduction, organisms such as bacteria (and some plants) create offspring that are genetically identical to the parent. Modern genetic technology can also be used to create clones. There are three types of cloning: gene cloning, reproductive cloning, and therapeutic cloning. Gene cloning is essentially recombinant DNA technology, where a piece of foreign DNA is inserted into a vector, which can be copied by a host cell. Therapeutic cloning involves the production of patient-matched stem cells for disease treatment. Here we focus on reproductive cloning of organisms.

Reproductive cloning is the process by which a whole organism is cloned. First, a cell is taken from the organism that is being cloned. The DNA from this donor cell is then transferred to an egg cell whose DNA has been removed. The egg cell is "activated" and begins dividing as if it was fertilized. An embryo results, and this embryo is then transferred to the uterus of a surrogate female. After gestation is complete, the surrogate will give birth to the clone, which is a genetic copy of the animal from which the original cell was taken.

The first animal to be successfully cloned was a sheep named Dolly, who was born in 1996. So far, cattle, chickens, dogs, cats, horses and several other mammals have been cloned. Japanese scientists have even announced efforts to clone a wooly mammoth. Wooly mammoths went extinct around 10,000 years ago. Global warming has caused thawing in permafrost regions in eastern Russia, and recently the remains of several well-preserved mammoths have been found. However, for cloning to work, the mammoth DNA will need to be in near-perfect condition.

Reproductive cloning can also be used to produce animals that are beneficial in a number of ways. Cloned animals can be used to test drug responses; one of the main benefits is that their reactions to the drugs should be uniform because they share all the same genetic material. Reproductive cloning is still highly inefficient, and cloned animals are not as healthy as animals born through sexual reproduction. While there may be many potential benefits to cloning in the future, the technology has to be refined and advanced before it is widespread.

CLICK HERE to learn more about recombinant DNA technology

REFERENCES

Campbell et al. Sheep cloned by nuclear transfer from a cultured cell line. Nature. 1996: 380 (6569): 64-66.

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Cloning A clone is a genetically identical copy of an organism, and it may be naturally occurring or created in the lab. Through the process of asexual reproduction, organisms such as bacteria (and some plants) create offspring that are genetically identical to the parent. Modern genetic technology can also be used to create clones.

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Starting in 1885 many scientists started to test different ways to clone animals such as frogs, sea urchins, and salamanders. In 1952 the first nuclear transplant was preformed starting modern cloning. The dolly sheep was the first mammal to be cloned on July 5, 1996.

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Dolly the sheep was born on July 5, 1996 and died in February 2003, after she was euthanized followingthe discovery of a progressive lung disease. Created by the Roslin Institute and biotechnology company PPL Therapeutics near Edinburgh, Scotland, Dolly's birth was heralded as the first cloning of a mammal. But that was not technically true.

Dolly was indeed the first mammal cloned from an adult somatic cell, as she was carved from the mammary tissue of a fully grown sheep. Cloning in biology is the process of producing genetically identical individuals, or the creation of a copy, which means that clones have been occurring in nature for years - with twins. By those standards, the first cloned animal was created in 1885.

In 1885, August Weissman produced a theory that he thought would explain why a cell, with all the information to create a human being, could be as highly specialized as a skin cell. He theorized that each daughter cell had half the amount of information as the cell from whence it came, thus diminishing the amount of genetic information.

Capitalizing on this, embryologist William Roux performed an experiment on a two-celled common frog embryo (a blastomere). Since the blastomere was two cells, they would each have the genetic material to create a frog. When he split them apart and destroyed the other cell with a hot needle, the result was half a frog, thus upholding Weissman's hypothesis.

Hans Adolf Edward Driesch attempted to repeat the experiment with four-celled sea urchins. He shook apart the blastomere. Instead of creating two different half-animals, he ended up with two sea urchins and effectively disproved Weissman's theory. Driesch recreated the experiment several times with sea urchins, and found the same thing. He came to the conclusion that, in destroying half of the blastomere, Roux had damaged the original cell.

Roux's and Driesch's work led to the work of Hans Spemann. Spemann worked with salamanders. Due to their tightly bonded natures, Spemann used his son's hair as a noose to separate the cells. They created two adult salamanders from the original salamander.

Spemann recreated his experiment, splitting apart the cells of more developed embryos. This time, he created only half-embryos. He determined that, after a period of time in the embryo's development which he called "determination," cells became specialized - thus paving the way for modern cell theory. Spemann is indeed called the father of cloning.

There were no major advances with cloning, however, until 1952. Then a team of scientists in Philadelphia cloned a frog embryo by implanting a nucleus from a fertilized cell into an unfertilized one. The cell realized that it was fertilized, and began to split and grow. It was the first time nuclear transplant, as a technique, had been used, and it still is used to this day.

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A History of Cloning Before Dolly the Sheep

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Dolly the sheep was born on July 5, 1996 and died in February 2003, after she was euthanized followingthe discovery of a progressive lung disease. Created by the Roslin Institute and biotechnology company PPL Therapeutics near Edinburgh, Scotland, Dolly's birth was heralded as the first cloning of a mammal.

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Cloning first begins by extracting a sample cell from the organism that is being cloned, and inserting it into an enucleated egg. This egg is inserted into a surrogate for it to be carried until birth.

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It sounds like science fiction, but it's not.

Any cat owner with $50,000 to spare can pay a Sausalito company, Genetic Savings & Clone, to clone Fluffy or Frisky this year.

The company already sponsored the first domestic cat clone -- a calico named CC (for "Carbon Copy") -- two years ago. Now, it is the first to go commercial, this time in its own laboratories, and five paying customers are lined up.

It has promised to produce nine cloned kittens by November. Six will be for clients and three for staff members, who will show off their clones at veterinary shows. None of the customers agreed to be interviewed.

The company got its start when iconoclastic octogenarian John Sperling, who made millions as founder of the University of Phoenix, backed research called "the Missyplicity Project" to clone a beloved husky mix, Missy.

The project was deluged by interested pet lovers, even though dog cloning continues to elude scientists. Genetic Savings says it is on track to clone Missy, who died in 2002 at age 15, this year.

"We would have had to be dumb not to see a business there," said Genetic Savings CEO Lou Hawthorne, a longtime family friend of Sperling, who suggested they turn the project into a for-profit venture.

Hawthorne is cloning his own pet, Tahini, a 6-month-old Bengal cat who likes to stalk deer in her Mill Valley backyard.

Hawthorne says he thinks the world is packed with pet lovers eager to follow suit. Studies show that a quarter of the 60 million pet-owning households would consider cloning their furry friends, he says. Genetic Savings hopes to be cloning thousands of pets annually in five years, when the cost should be down to $10,000 for cats, $20,000 for dogs, he says.

"A great pet is like a work of art, especially if it's a one-of-a-kind mixed breed," Hawthorne said. "To replicate these qualities adds to the sum of joy in the world."

But critics say that's faulty logic.

"Cloning undermines the sacred and intrinsic value of what a unique life is all about in the world," said Jeremy Rifkin, author of "Biotech Century," a cautionary work about the Pandora's box that scientific advances like cloning might open.

"We just had a German shepherd who passed away, who was the love of our life," Rifkin said, speaking for himself and his wife. "We'd love to see that dog again, but we would never clone it. It would be a complete betrayal of our unique relationship with that beautiful companion animal to clone another animal from it."

David Magnus, co-director of the Center for Biomedical Ethics at Stanford University, agreed.

"My cocker spaniel, who we had for 15 years, just passed away, and I would do anything to have him back and young again, but it can't happen," he said.

"The people who want this are spending huge sums of money to get their pet immortalized or to guarantee they're getting a pet exactly like the one they had before, and it's simply not possible," Magnus said.

Despite the criticisms, animal cloning is legal in the United States, although human cloning is not.

To be sure, Genetic Savings & Clone sounds straight out of the Arnold Schwarzenegger techno thriller "The 6th Day," set in the year 2010, in which a pet-cloning company called RePet was as ubiquitous as Kinko's.

Hawthorne, 43, a Princeton grad and former multimedia producer with a mop of salt-and-pepper curls and a quick wit woven with whimsy, is quick to correct misperceptions.

Unlike the fictional RePet, his company will produce unique, newborn animals, not full-grown exact replicas, he said. A cloned animal will have its own personality and memories. It will closely resemble the original animal in physical appearance and behavioral tendencies. The company says it will never experiment with human cloning.

He pointed to some potential benefits for society: cloning working animals, such as seeing-eye dogs and search-and-rescue dogs.

Cloning is not a substitute for the grieving process, Hawthorne said. It's best suited for mutts -- "a breed of one" -- which are past breeding age or spayed or neutered.

Several hundred people have signed up to have Genetic Savings preserve tissue from their cat or dog for future cloning. They pay about $900 plus $150 a year for maintenance. Cells are harvested through a skin biopsy done by a veterinarian, who removes a pencil-eraser-sized skin sample from the pet's belly and from inside its mouth.

Menlo Park resident Jayne Lange, 47, has banked tissue from two Shiba Inu dogs, one still living and one deceased. The breed evolved from ancient Japanese fighting dogs, she said. "They tend to be fiercely loyal and are very cute little dogs, red with a curly tail," she said.

She was motivated to do it for her three teenage children.

"It's almost like creating a family tradition," she said. "We love our dogs so much. If at some future point my children thought back about Akeya and wanted a dog like it, they'd have the opportunity."

Tom Minot, 56, a vice president of marketing at a Silicon Valley company, also used the word "family" in describing why he banked tissue from his dog, Fred, an 8-year-old Australian shepherd and border collie mix.

"I'm single, and he's my family," Minot said. "He's an exceptional dog."

The world's first cloned cat, CC, by contrast, is just a regular cat, according to her owner, Duane Kraemer, a professor of veterinary medicine who was on the Texas A&M team that cloned her.

"She's a very good house pet," he said. Kraemer hopes to breed her -- the old-fashioned way -- "whenever we find a worthy male."

CC also demonstrates some limits of cloning. As Hawthorne ruefully said, the calico cat is "a problem child, the first clone that doesn't resemble its genetic mom."

Calicos are essentially a three-dimensional mosaic of two cell types, one with genes for black-and-white coat patterns, the other with genes for orange and white. Because CC was cloned from a single cell, she got only the black- and-white gene, unlike her "mom," the typical calico mix of both types.

Genetic Savings is no longer affiliated with Texas A&M. Instead, it has its own labs in Austin, Texas, and San Diego, and it plans one in Madison, Wis.

Sperling's deep pockets have helped Genetic Savings vault ahead of competitors. So far, it has spent $10 million and expects to spend another $5 million by the time it breaks even, which Hawthorne predicts will be next year.

Its scientists use the cloning procedure familiar to the world since Dolly the sheep was born in 1997: They take the nucleus of a cell from the original animal and inject it into an egg whose own nucleus has been removed. (Eggs are purchased from spay clinics.) The resulting embryo is then implanted into a surrogate mother.

Most cloning failures occur either in the test tube, if the egg and cell fail to develop, or shortly after implantation, if the embryo is spontaneously aborted. It took 87 tries to produce CC, for example, Kraemer said.

Genetic Savings has licensed an innovation, already used in cattle cloning, that it says increases the success rate. The technique, called chromatin transfer, removes all the "adult factors" associated with the cell to be transferred, essentially regressing that cell back to an embryonic stage. That means the egg doesn't have to do the extra work of reprogramming the donor cell into an embryo.

Not surprisingly, pet metaphors seem to creep into Hawthorne's speech. "I'm like a pit bull. I can be relentless in focusing until the problem can be resolved," he said. The intense public interest in his business makes it "like working in a fishbowl."

As for his company's success: "The proof is in the puddy-cat."

Cloning kitty

1 Cloning process begins with a tissue biopsy from the cat to be cloned.

2 The sample is cultured and cells are frozen.

3 A host cat's egg is enucleated, meaning the genetic material is removed.

4 The host cat's cell is treated to remove differentiation. Differentiation is when cells are assigned to develop specialized functions such as muscle cells, neurons or skin cells.

5 The treated donor cell is combined with the enucleated egg by electrofusion, resulting in a singlecelled cloned embryo.

6 The surrogate mother cat, in estrus, has the cloned embryos implanted in her oviduct.

7 The surrogate mother carries the pregnancy to term, giving birth to cloned kittens.

Source: Genetic Savings & Clone

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Here, kitty-kitty-kitty-kitty / Sausalito firm offers clones for $50,000, signs up 5 cat owners

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Any cat owner with $50,000 to spare can pay a Sausalito company, Genetic Savings & Clone, to clone Fluffy or Frisky this year. The company got its start when iconoclastic octogenarian John Sperling, who made millions as founder of the University of Phoenix, backed research called "the Missyplicity Project" to clone a beloved husky mix, Missy.

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DNA from the cell of an adult animal is removed and inserted into an egg cell from another animal. After, the new embryo is zapped with electricity so it could multiply until small cells form after egg is fertilized

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Cloning refers to the process of developing an embryo with the DNA from an adult animal.

Credit: Dreamstime

Cloning may invoke an image of an army of identical cows or sheep churned out factory-style, but in actuality, the process is much more laborious.

The term " cloning" generally applies to a process more technically known as somatic cell nuclear transfer. What that means is that the DNA from the cell of an adult animal (take cows, for example), called the "donor," is extracted from the cell (usually a skin cell taken in a biopsy) and inserted into an egg cell from another cow. The egg cell has had its nucleus removed so that it will read and duplicate the DNA of the donor cell.

The newly created embryo is then zapped with electricity so that it starts multiplying, until it becomes a blastocyst (a small clump of cells that forms after an egg is fertilized), which is then implanted into a surrogate mother. The resulting newborn will be an identical genetic replica to the donor cow.

Cows have been cloned more than other animals because obtaining eggs from the cow is slightly easier than for swine, said geneticist Bill Muir of Purdue University, an author of a 2002 National Academy of Sciences report on the scientific concerns of animal biotechnology.

This process differs from other methods of artificial breeding, such as in vitro fertilization, in that it uses adult cells, instead of embryos.

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Cloning may invoke an image of an army of identical cows or sheep churned out factory-style, but in actuality, the process is much more laborious. The term " cloning" generally applies to a process more technically known as somatic cell nuclear transfer.