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For the cloning of human beings, see Human cloning. Human cloning is the creation of a genetically identical copy of a Human being human cell, or human tissue. For other uses, see Cloning (disambiguation).

Cloning is the process of making an identical copy of something. In biology, it collectively refers to processes used to create copies of DNA fragments (molecular cloning), cells (cell cloning), or organisms. Foundations of modern biology There are five unifying principles Deoxyribonucleic acid ( DNA) is a Nucleic acid that contains the genetic instructions used in the development and functioning of all known The cell is the structural and functional unit of all known living Organisms It is the smallest unit of an organism that is classified as living and is often called The term also covers when organisms such as bacteria, insects or plants reproduce asexually. The Bacteria ( singular: bacterium) are a large group of unicellular Microorganisms Typically a few Micrometres in length bacteria have Insects ( Class Insecta) are a major group of Arthropods and the most diverse group of Animals on the Earth with over a million described Plants are living Organisms belonging to the kingdom Plantae. Asexual reproduction is a form of reproduction which does not involve Meiosis, Ploidy reduction or Fertilization.

Contents

Etymology

The term clone is derived from κλών, the Greek word for "twig, branch", referring to the process whereby a new plant can be created from a twig. Greek (el ελληνική γλώσσα or simply el ελληνικά — "Hellenic" is an Indo-European language, spoken today by 15-22 million people mainly In horticulture, the spelling clon was used until the twentieth century; the final e came into use to indicate the vowel is a "long o" instead of a "short o". Horticulture is the art and science of plant cultivation Horticulturists (or horticuluralists) work and conduct research in the fields of Plant propagation Since the term entered the popular lexicon in a more general context, the spelling clone has been used exclusively.

Molecular cloning

Main article: Molecular cloning

Molecular cloning refers to the procedure of isolating a defined DNA sequence and obtaining multiple copies of it. Molecular cloning refers to the procedure of isolating a defined DNA sequence and obtaining multiple copies of it In vivo. Deoxyribonucleic acid ( DNA) is a Nucleic acid that contains the genetic instructions used in the development and functioning of all known Cloning is frequently used to amplify DNA fragments containing genes, but it can be used to amplify any DNA sequence such as promoters, non-coding sequences and randomly fragmented DNA. History See also History of genetics The existence of genes was first suggested by Gregor Mendel (1822-1884 who in the 1860s studied inheritance In Biology, a promoter is a region of DNA that facilitates the transcription of a particular Gene. It is used in a wide array of biological experiments and practical applications such as large scale protein production. Occasionally, the term cloning is misleadingly used to refer to the identification of the chromosomal location of a gene associated with a particular phenotype of interest, such as in positional cloning. A chromosome is an organized structure of DNA and Protein that is found in cells. A genetic screen (often shortened to screen) is a procedure or test to identify and select individuals who possess a Phenotype of interest In practice, localization of the gene to a chromosome or genomic region does not necessarily enable one to isolate or amplify the relevant genomic sequence.

In practice, in order to amplify any DNA sequence in a living organism, that sequence must be linked to an origin of replication, which is a sequence of DNA capable of directing the propagation of itself and any linked sequence. The Origin of replication (also called the replication origin) is a particular sequence in a Genome at which replication is initiated However, a number of other features are needed and a variety of specialised cloning vectors exist that allow protein expression, tagging, single stranded RNA and DNA production and a host of other manipulations. A cloning vector is a small DNA vehicle into which a foreign DNA fragment can be inserted Ribonucleic acid ( RNA) is a Nucleic acid that consists of a long chain of Nucleotide units

Cloning of any DNA fragment essentially involves four steps: fragmentation, ligation, transfection, and screening/selection. Although these steps are invariable among cloning procedures a number of alternative routes can be selected, these are summarized as a ‘cloning strategy’.

Initially, the DNA of interest needs to be isolated to provide a DNA segment of suitable size. Subsequently, a ligation procedure is used where the amplified fragment is inserted into a vector. The vector (which is frequently circular) is linearised using restriction enzymes, and incubated with the fragment of interest under appropriate conditions with an enzyme called DNA ligase. A restriction enzyme (or restriction Endonuclease) is an Enzyme that cuts double-stranded DNA at specific recognition Nucleotide In Molecular biology, DNA ligase is a special type of Ligase ( that can link together two DNA strands that have single-strand breaks (a break in both complementary Following ligation the vector with the insert of interest is transfected into cells. A number of alternative techniques are available, such as chemical sensitivation of cells, electroporation and biolistics. Finally, the transfected cells are cultured. As the aforementioned procedures are of particularly low efficiency, there is a need to identify the cells that have been successfully transfected with the vector construct containing the desired insertion sequence in the required orientation. Modern cloning vectors include selectable antibiotic resistance markers, which allow only cells in which the vector has been transfected, to grow. In modern usage an antibiotic is a Chemotherapeutic agent with activity against Microorganisms such as Bacteria, fungi or Protozoa Additionally, the cloning vectors may contain colour selection markers which provide blue/white screening (α-factor complementation) on X-gal medium. Nevertheless, these selection steps do not absolutely guarantee that the DNA insert is present in the cells obtained. Further investigation of the resulting colonies is required to confirm that cloning was successful. This may be accomplished by means of PCR, restriction fragment analysis and/or DNA sequencing. The term DNA sequencing encompasses biochemical methods for determining the order of the Nucleotide bases Adenine, Guanine, Cytosine

Cellular cloning

Cloning cell-line colonies using cloning rings
Cloning cell-line colonies using cloning rings

Cloning a cell means to derive a population of cells from a single cell. In the case of unicellular organisms such as bacteria and yeast, this process is remarkably simple and essentially only requires the inoculation of the appropriate medium. Inoculation is the placement of something to where it will grow or reproduce and is most commonly used in respect of the introduction of a serum Vaccine, or antigenic substance However, in the case of cell cultures from multi-cellular organisms, cell cloning is an arduous task as these cells will not readily grow in standard media.

A useful tissue culture technique used to clone distinct lineages of cell lines involves the use of cloning rings (cylinders)[1]. According to this technique, a single-cell suspension of cells which have been exposed to a mutagenic agent or drug used to drive selection is plated at high dilution to create isolated colonies; each arising from a single and potentially clonally distinct cell. In Biology, a mutagen ( Latin, literally origin of change) is a physical or chemical agent that changes the genetic information (usually DNA) In the context of Evolution, certain traits or Alleles of a Species may be subject to selection At an early growth stage when colonies consist of only a few of cells, sterile polystyrene rings (cloning rings), which have been dipped in grease are placed over an individual colony and a small amount of trypsin is added. Polystyrene ˌpɒliˈstaɪriːn ( IUPAC Polyphenylethene is an aromatic Polymer made from the aromatic Monomer Styrene Trypsin ( is a Serine protease found in the Digestive system, where it breaks down Proteins Trypsin predominantly cleaves peptide chains at the carboxyl Cloned cells are collected from inside the ring and transferred to a new vessel for further growth.

Cloning in stem cell research

Main article: Somatic cell nuclear transfer

Somatic cell nuclear transfer can also be used to create a clonal embryo. Genetics and Developmental biology, somatic cell nuclear transfer ( SCNT) is a Laboratory technique for creating an Ovum with a donor Genetics and Developmental biology, somatic cell nuclear transfer ( SCNT) is a Laboratory technique for creating an Ovum with a donor The most likely purpose for this is to produce embryos for use in research, particularly stem cell research. Stem cells are cells found in most if not all multi-cellular Organisms. This process is also called "research cloning" or "therapeutic cloning. " The goal is not to create cloned human beings, but rather to harvest stem cells that can be used to study human development and to potentially treat disease. While a clonal human blastocyst has been created, stem cell lines are yet to be isolated from a clonal source. [2]

Organism cloning

Main article: Asexual reproduction

Organism cloning refers to the procedure of creating a new multicellular organism, genetically identical to another. Asexual reproduction is a form of reproduction which does not involve Meiosis, Ploidy reduction or Fertilization. In essence this form of cloning is an asexual method of reproduction, where fertilization or inter-gamete contact does not take place. Asexual reproduction is a naturally occurring phenomenon in many species, including most plants (see vegetative reproduction) and some insects. Vegetative reproduction is a type of Asexual reproduction found in plants and is also called vegetative propagation or vegetative multiplication.

Horticultural

The term clone is used in horticulture to mean all descendants of a single plant, produced by vegetative reproduction or apomixis. Vegetative reproduction is a type of Asexual reproduction found in plants and is also called vegetative propagation or vegetative multiplication. Many horticultural plant cultivars are clones, having been derived from a single individual, multiplied by some process other than sexual reproduction. A cultivar is a cultivated Plant that has been selected and given a unique name because of its decorative or useful characteristics it is usually distinct from similar As an example, some European cultivars of grapes represent clones that have been propagated for over two millennia. For the Tokyo University supercomputer see Gravity Pipe. GRAPE, or GRA phics P rogramming E nvironment is Other examples are potato and banana. The potato is a Starchy Tuberous crop Vegetable from the perennial Solanum tuberosum of the Solanaceae For the fruit see Banana. For other meanings see Banana (disambiguation. Grafting can be regarded as cloning, since all the shoots and branches coming from the graft are genetically a clone of a single individual, but this particular kind of cloning has not come under ethical scrutiny and is generally treated as an entirely different kind of operation. Grafting is a method of asexual Plant propagation widely used in Agriculture and Horticulture where the tissues of one Plant are encouraged to Ethics is a major branch of Philosophy, encompassing right conduct and good life Grafting, and hence cloning, of apples, pears, peaches, almonds, and persimmons can be traced back at least to 5000BC, as performed by the Chinese diplomat Feng Li[3].

Many trees, shrubs, vines, ferns and other herbaceous perennials form clonal colonies. A tree is a perennial Woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or A shrub or Bush is a horticultural rather than strictly botanical category of Woody plant, distinguished from a Tree A vine is any plant of Genus Vitis (the Grape plants or by extension any similar climbing or trailing plant A fern is any one of a group of about 20000 Species of Plants classified in the phylum or division Pteridophyta, also known as Filicophyta A perennial plant or perennial ( Latin per, "through" annus, "year" is a Plant that lives for more than "Ramet" redirects here For the commune in Alba County, Romania see Râmeţ. Parts of a large clonal colony often become detached from the parent, termed fragmentation, to form separate individuals. Some plants also form seeds asexually, termed apomixis, e. A seed (in some plants referred to as a kernel) is a small embryonic Plant enclosed in a covering called the seed coat usually with some stored g. dandelion.

Parthenogenesis

Clonal derivation exists in nature in some animal species and is referred to as parthenogenesis. Parthenogenesis (from the Greek παρθένος parthenos, "virgin" + γένεσις genesis, "creation" is an asexual form An example is the "Little Fire Ant" (Wasmannia auropunctata), which is native to Central and South America but has spread throughout many tropical environments. Fire ants, (referred to as red ants in the UK) are stinging Ants with over 280 species worldwide Fire ants, (referred to as red ants in the UK) are stinging Ants with over 280 species worldwide South America is a Continent of the Americas, situated entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a

Reproductive cloning

Reproductive cloning uses "somatic cell nuclear transfer" (SCNT) to create animals that are genetically identical. Genetics and Developmental biology, somatic cell nuclear transfer ( SCNT) is a Laboratory technique for creating an Ovum with a donor This process entails the transfer of a nucleus from a donor adult cell (somatic cell) to an egg which has no nucleus. If the egg begins to divide normally it is transferred into the uterus of the surrogate mother.

Such clones are not strictly identical since the somatic cells may contain mutations in their nuclear DNA. Additionally, the mitochondria in the cytoplasm also contains DNA and during SCNT this DNA is wholly from the donor egg, thus the mitochondrial genome is not the same as that of the nucleus donor cell from which it was produced. In Cell biology, a mitochondrion (plural mitochondria) is a membrane-enclosed Organelle found in most eukaryotic cells. The cytoplasm is the contents of a cell that is enclosed within the Plasma membrane. In Cell biology, a mitochondrion (plural mitochondria) is a membrane-enclosed Organelle found in most eukaryotic cells. This may have important implications for cross-species nuclear transfer in which nuclear-mitochondrial incompatibilities may lead to death.

Dolly the Sheep

Main article: Dolly the Sheep

Dolly (1996-07-05 – 2003-02-14), a Finn Dorsett ewe, 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 1952. Dolly was a ewe ( July 5, 1996 – February 14, 2003) that was the first Animal to be cloned from an adult Dolly was a ewe ( July 5, 1996 – February 14, 2003) that was the first Animal to be cloned from an adult Year 1996 ( MCMXCVI) was a Leap year starting on Monday (link will display full 1996 Gregorian calendar) Events 1295 - Scotland and France form an alliance the beginnings of the Auld Alliance, against England. Year 2003 ( MMIII) was a Common year starting on Wednesday of the Gregorian calendar. Events 842 - Charles the Bald and Louis the German swear the Oaths of Strasbourg in the French and German She was cloned at the Roslin Institute in Scotland and lived there until her death when she was six. The Roslin Institute is a government research institute at Roslin, a village in Midlothian, Scotland, that is sponsored by the Biotechnology Scotland ( Gaelic: Alba) is a Country in northwest Europethat occupies the northern third of the island of Great Britain. On 2003-04-09 her stuffed remains were placed at Edinburgh's Royal Museum, part of the National Museums of Scotland. Year 2003 ( MMIII) was a Common year starting on Wednesday of the Gregorian calendar. Events 193 - Septimius Severus is proclaimed Roman Emperor by the army in Illyricum (in the Balkans) Taxidermy ( Greek for "skin arrangement" is the art of mounting or reproducing Animals for display (e For other museums called the Royal Museum see Royal Museum (disambiguation. National Museums Scotland is the family of several National museums in Scotland.

Dolly was publicly significant because the effort showed that the 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 this demonstration, there was no proof for the widely spread hypothesis that differentiated animal cells can give rise to entire new organisms.

Cloning Dolly the sheep had a 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. Seventy calves have been created from 9,000 attempts and one third of them died young; Prometea took 328 attempts. Prometea (born May 28, 2003) is a Haflinger foal the first cloned Horse and the first to be born from and carried by its cloning mother Notably, although the first clones were frogs, no adult cloned frog has yet been produced from a somatic adult nucleus donor cell.

There were early claims that Dolly the Sheep had pathologies resembling accelerated aging. Dolly was a ewe ( July 5, 1996 – February 14, 2003) that was the first Animal to be cloned from an adult Scientists speculated that Dolly's death in 2003 was related to the shortening of telomeres, DNA-protein complexes that protect the end of linear chromosomes. A telomere is a region of repetitive DNA at the end of Chromosomes which protects the end of the chromosome from destruction A chromosome is an organized structure of DNA and Protein that is found in cells. However, other researchers, including Ian Wilmut who led the team that successfully cloned Dolly, argue that Dolly's early death due to respiratory infection was unrelated to deficiencies with the cloning process. Prof Sir Ian Wilmut OBE (born July 7 1944) is an Scottish Embryologist and is currently one of the leaders of the Queen's Medical


Species cloned

Further information: List of animals that have been cloned

The modern cloning techniques involving nuclear transfer have been successfully performed on several species. This is a list of animals that have been cloned in alphabetical order Process Nuclear Transfer is a form of Cloning. The steps involve removing the DNA from an Oocyte (unfertilized Landmark experiments in chronological order:

Human cloning

Main article: Human cloning

Human cloning is the creation of a genetically identical copy of an existing or previously existing human. Human cloning is the creation of a genetically identical copy of a Human being human cell, or human tissue. Genetics (from Ancient Greek grc-Latn genetikos, “genitive” and that from grc-Latn genesis, “origin” a discipline of Biology, is Human beings, humans or man (Origin 1590–1600 L homō man OL hemō the earthly one (see Humus The term is generally used to refer to artificial human cloning; human clones in the form of identical twins are commonplace, with their cloning occurring during the natural process of reproduction. Twins are Offspring resulting from the same Pregnancy, either of the same or opposite Sex. There are two commonly discussed types of human cloning: therapeutic cloning and reproductive cloning. Therapeutic cloning involves cloning cells from an adult for use in medicine and is an active area of research: while reproductive cloning would involve making cloned human beings. Such reproductive cloning has not been performed and is illegal in many countries. A third type of cloning called replacement cloning is a theoretical possibility, and would be a combination of therapeutic and reproductive cloning. Replacement cloning would entail the replacement of an extensively damaged, failed, or failing body through cloning followed by whole or partial brain transplant. A whole-body transplant or brain transplant is a hypothetical operation that would move the brain of one being into the body of another

The various forms of human cloning are controversial. [7] There have been numerous demands for all progress in the human cloning field to be halted. Some people and groups oppose therapeutic cloning, but most scientific, governmental and religious organizations oppose reproductive cloning. The American Association for the Advancement of Science (AAAS) and other scientific organizations have made public statements suggesting that human reproductive cloning be banned until safety issues are resolved [8]. The American Association for the Advancement of Science (or AAAS) is an organization that promotes cooperation between Scientists defends scientific freedom encourages Serious ethical concerns have been raised by the idea that it might be possible in the future to harvest organs from clones. Bioethics is the philosophical study of the ethical controversies brought about by advances in Biology and Medicine. Some people have considered the idea of growing organs separately from a human organism - in doing this, a new organ supply could be established without the moral implications of harvesting them from humans. Research is also being done on the idea of growing organs that are biologically acceptable to the human body inside of other organisms, such as pigs or cows, then transplanting them to humans, a form of xenotransplantation. Xenotransplantation ( xeno- from the Greek meaning "foreign" is the transplantation of living cells tissues or organs

The first human hybrid human clone was created in November 1998, by American Cell Technologies. [9]. It was created from a man's leg cell, and a cow's egg whose DNA was removed. It was destroyed after 12 days. Since a normal embryo implants at 14 days, Dr Robert Lanza, ACT's director of tissue engineering, told the Daily Mail newspaper that the embryo could not be seen as a person before 14 days. Robert Lanza is Chief Scientific Officer of Advanced Cell Technology (ACT and Adjunct Professor at the Institute for Regenerative Medicine Wake Forest University While making an embryo, which may have resulted in complete human had it been allowed to come to term, according to ACT: "[ACT's] aim was 'therapeutic cloning' not 'reproductive cloning'"

On January, 2008, Wood and Andrew French, Stemagen's chief scientific officer in California, announced that they successfully created the first 5 mature human embryos using DNA from adult skin cells, aiming to provide a source of viable embryonic stem cells. California ( is a US state on the West Coast of the United States, along the Pacific Ocean. Deoxyribonucleic acid ( DNA) is a Nucleic acid that contains the genetic instructions used in the development and functioning of all known Stem cells are cells found in most if not all multi-cellular Organisms. Dr. Samuel Wood and a colleague donated skin cells, and DNA from those cells was transferred to human eggs. Samuel Wood may be Samuel Wood, CEO MD and scientist who cloned himself It is not clear if the embryos produced would have been capable of further development, but Dr. Wood stated that if that were possible, using the technology for reproductive cloning would be both unethical and illegal. The 5 cloned embryos, created in Stemagen Corporation lab, in La Jolla, were destroyed. La Jolla (ləˈhɔɪə "luh-HOY-uh") is a wealthy Seaside resort community of up to 42808 residents within the city of San Diego, California [10]

Ethical issues of cloning

Main article: Ethics of cloning

Although the practice of cloning organisms has been widespread for several thousands of years in the form of horticultural cloning, the recent technological advancements that have allowed for cloning of animals (and potentially humans) have been highly controversial. In Bioethics, the ethics of cloning refers to a variety of Ethical positions regarding the practice and possibilities of Cloning, especially Human Some believe it is unethical to use a human clone to save the life of another. Others have countered that people who exist today and have interpersonal relationships and personal histories should take precedence over never-conscious life at any stage of developmental maturity. The Catholic Church and various traditionalist religious groups oppose all forms of cloning, on the grounds that life begins at conception. Conversely, Judaism does not equate life with conception and, though some question the wisdom of cloning, Orthodox rabbis generally find no firm reason in Jewish law and ethics to object to cloning. Halakha ( הלכה; alternative transliterations include Halocho and Halacha) is the collective body of Jewish Religious law [11] From the standpoint of classical liberalism, concerns also exist regarding the protection of the identity of the individual and the right to protect one's genetic identity. Liberalism is a broad array of related ideas and theories of Government that consider individual Liberty to be the most important political goal

Gregory Stock is a scientist and outspoken critic against restrictions on cloning research. Gregory Stock is a biophysicist, best-selling author biotech entrepreneur and the former director of the Program on Medicine Technology and Society at UCLA ’s [12]

The social implications of an artificial human production scheme were famously explored in Aldous Huxley's novel Brave New World. Aldous Leonard Huxley (26 July 1894 &ndash 22 November 1963 was an English writer and one of the most prominent members of the famous Huxley family. Brave New World is a 1932 Novel by Aldous Huxley. Set in the London of AD 2540 (632 A

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 such as swine, goats and cattle have no differences from the conventionally bred animals.

Joseph Mendelson, legal director of the Center for Food Safety, said that cloned food still should be labeled due to the fact that safety and ethical issues of it remain questionable.

Carol Tucker Foreman, director of food policy at the Consumer Federation of America, stated that FDA does not consider the fact that the results of some studies revealed that cloned animals have increased rates of mortality and deformity at birth. The Consumer Federation of America (CFA is a Non-profit organization founded in 1968 to advance the consumer interest through research education and advocacy

FDA specialists mentioned that when the cloned animals are aged from 6 to 18 months, they are almost similar to conventionally bred animals. The food receives a certain label only in cases when its features are modified by the way it is produced. [13]

Cloning extinct and endangered species

Cloning, or more precisely, the reconstruction of functional DNA from extinct species has, for decades, been a dream of some scientists. In Biology and Ecology, extinction is the cessation of existence of a Species or group of taxa. The possible implications of this were dramatized in the best-selling novel by Michael Crichton and high budget Hollywood thriller Jurassic Park. Jurassic Park, a book by Michael Crichton, with a film version directed by Steven Spielberg, revolves around the resurrection John Michael Crichton, ˈkraɪtən, (born October 23 1942 is an American author Film producer, Film director, Medical doctor, and Television producer Jurassic Park is a 1993 Science fiction film directed by Steven Spielberg and based on the novel of the same name by Michael In real life, one of the most anticipated targets for cloning was once the Woolly Mammoth, but attempts to extract DNA from frozen mammoths have been unsuccessful, though a joint Russo-Japanese team is currently working toward this goal. The woolly mammoth ( Mammuthus primigenius) also called the tundra mammoth, is an extinct species of Mammoth. [14]

In 2001, a cow named Bessie gave birth to a cloned Asian gaur, an endangered species, but the calf died after two days. The gaur (ˈɡaʊɚ ( Bos gaurus, previously Bibos gauris) is a large dark-coated bovine animal of South Asia and Southeast Asia. In 2003, a banteng was successfully cloned, followed by three African wildcats from a thawed frozen embryo. The Banteng, Bos javanicus is an Ox that is found in Burma, Thailand, Cambodia, Laos, Vietnam, Borneo These successes provided hope that similar techniques (using surrogate mothers of another species) might be used to clone extinct species. Anticipating this possibility, tissue samples from the last bucardo (Pyrenean Ibex) were frozen immediately after it died. The Pyrenean Ibex ( Capra pyrenaica pyrenaica) is an Ibex, one of the two extinct Subspecies of Spanish Ibex. Researchers are also considering cloning endangered species such as the giant panda, ocelot, and cheetah. The "Frozen Zoo" at the San Diego Zoo now stores frozen tissue from the world's rarest and most endangered species. A frozen zoo is a Cryogenic facility for the long term storage of animal and plant genetic material such as DNA, Sperm, eggs, and Embryos The San Diego Zoo in Balboa Park, San Diego, California is one of the largest most progressive Zoos in the world with over 4000 animals [15][16]

In 2002, geneticists at the Australian Museum announced that they had replicated DNA of the Thylacine (Tasmanian Tiger), extinct about 65 years previous, using polymerase chain reaction. The Australian Museum is the oldest Museum in Australia, with an international reputation in the fields of Natural history and Anthropology. The Thylacine (ˈθaɪləsaɪn -iːn ( Thylacinus cynocephalus Latin wolf-headed pouched dog was the largest known carnivorous Marsupial of modern [17] However, on 2005-02-15 the museum announced that it was stopping the project after tests showed the specimens' DNA had been too badly degraded by the (ethanol) preservative. Year 2005 ( MMV) was a Common year starting on Saturday (link displays full calendar of the Gregorian calendar. Events 590 - Khosrau II is crowned as king of Persia 1637 - Ferdinand III becomes Holy Roman Emperor Most recently, on 2005-05-15, it was announced that the Thylacine project would be revived, with new participation from researchers in New South Wales and Victoria. Year 2005 ( MMV) was a Common year starting on Saturday (link displays full calendar of the Gregorian calendar. Events 1252 - Pope Innocent IV issues the Papal bull Ad exstirpanda, which authorizes but also limits the

One of the continuing obstacles in the attempt to clone extinct species is the need for nearly perfect DNA. Cloning from a single specimen could not create a viable breeding population in sexually reproducing animals. Furthermore, even if males and females were to be cloned, the question would remain open whether they would be viable at all in the absence of parents that could teach or show them their natural behavior. Essentially, if cloning an extinct species were successful — it must be considered that cloning is still an experimental technology that succeeds only by chance. It is far more likely than not that any resulting animals, even if they were healthy, would be little more than curios or museum pieces.

Cloning endangered species is a highly ideological issue. Many conservation biologists and environmentalists vehemently oppose cloning endangered species — not because they think it won't work but because they think it may deter donations to help preserve natural habitat and wild animal populations. "Conservation Biology" redirects here For the Scientific journal, see Conservation Biology (journal. Environmentalism is a broad philosophy and Social movement centered on a concern for the conservation and improvement of the environment. The "rule-of-thumb" in animal conservation is that, if it is still feasible to conserve habitat and viable wild populations, breeding in captivity should not be undertaken in isolation. A rule of thumb is a principle with broad application that is not intended to be strictly accurate or reliable for every situation

In a 2006 review, David Ehrenfeld concluded that cloning in animal conservation is an experimental technology that, at its state in 2006, could not be expected to work except by pure chance and utterly failed a cost-benefit analysis. Cost-benefit analysis is a term that refers both to a formal discipline used to help appraise or assess the case for a Project or proposal which itself is [18] Furthermore, he said, it is likely to siphon funds from established and working projects and does not address any of the issues underlying animal extinction (such as habitat destruction, hunting or other overexploitation, and an impoverished gene pool). While cloning technologies are well-established and used on a regular basis in plant conservation, care must be taken to ensure genetic diversity. He concluded:

“ Vertebrate cloning poses little risk to the environment, but it can consume scarce conservation resources, and its chances of success in preserving species seem poor. To date, the conservation benefits of transgenics and vertebrate cloning remain entirely theoretical, but many of the risks are known and documented. Conservation biologists should devote their research and energies to the established methods of conservation, none of which require transgenics or vertebrate cloning. [18] ”

References

  1. ^ McFarland, Douglas (2000). "Preparation of pure cell cultures by cloning". Methods in Cell Science 22 (1): 63-66. PMID 10650336.  
  2. ^ Gil, Gideon. "California biotech says it cloned a human embryo, but no stem cells produced", Boston Globe, 2008-01-17. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common Events 38 BC - Octavian marries Livia Drusilla. 1287 - King Alfonso III of Aragon invades Minorca  
  3. ^ Great Moments in Apple History
  4. ^ BLOODLINES. Timeline
  5. ^ whoiswho.ru
  6. ^ Wikinews: Endangered cow cloned in Brazil, 22 May 2005
  7. ^ Pence, Gregory E. (1998). Gregory E Pence is a Professor in the department of Philosophy at the University of Alabama at Birmingham. Who’s Afraid of Human Cloning?. Rowman & Littlefield. paperback ISBN 0-8476-8782-1 and hardcover ISBN 0-8476-8781-3.  
  8. ^ AAAS Statement on Human Cloning.
  9. ^ BBC News | SCI/TECH | Details of hybrid clone revealed
  10. ^ Mature Human Embryos Created From Adult Skin Cells Washingtonpost. com
  11. ^ Michael Brody. Michael Brody (born 1954 is a Hungarian linguist and Emeritus Professor of Linguistics at University College London. Avraham Steinberg.
  12. ^ New Page 0
  13. ^ Meat of Cloned Food is Safe to Eat, FDA Says
  14. ^ "Scientists 'to clone mammoth'", BBC News, 2003-08-18. Year 2003 ( MMIII) was a Common year starting on Wednesday of the Gregorian calendar. Events 293 BC - The oldest known Roman temple to Venus is founded starting the institution of Vinalia Rustica.  
  15. ^ Heidi B. Perlman. "Scientists Close on Extinct Cloning", Associated Press, 2000-10-08. 2000 ( MM) was a Leap year that started on Saturday of the Common Era, in accordance with the Gregorian calendar. Events 314 - Roman Emperor Licinius is defeated by his colleague Constantine I at the Battle of Cibalae, and loses  
  16. ^ Pence, Gregory E. (2005). Gregory E Pence is a Professor in the department of Philosophy at the University of Alabama at Birmingham. Cloning After Dolly: Who's Still Afraid?. Rowman & Littlefield. ISBN 0-7425-3408-1.  
  17. ^ Holloway, Grant. "Cloning to revive extinct species", CNN. com, 2002-05-28. See also 2002 (disambiguation Year 2002 ( MMII) was a Common year starting on Tuesday of the Gregorian calendar. Events 585 BC - A Solar eclipse occurs as predicted by Greek philosopher and scientist Thales, while Alyattes is battling  
  18. ^ a b Ehrenfeld, David (2006). "Transgenics and Vertebrate Cloning as Tools for Species Conservation". Conservation Biology 20 (3): 723-732. doi:10.1111/j.1523-1739.2006.00399.x. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document. PMID 16909565.  

External links and references

Dictionary

cloning

-verb

  1. Present participle of clone.

-noun

  1. (biology) The production of a cloned embryo by transplanting the nucleus of a somatic cell into an ovum
  2. (by extension) The production of an exact copy of an object
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