Clone

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A clone is any cell or individual which is identical to another.

In biology, cloning is the process of producing one or more genetically-identical individuals. With whole individuals, it usually means the deliberate production of an identical copy. This was first achieved in mammals with the famous Dolly the sheep. Human identical twins are natural clones. So are the offspring of asexual reproduction, and any parthenogenetic reproduction which does not involve meiosis.[1]

Cloning is natural to some animals, but rare in mammals. An exception is the Nine-banded armadillo, which normally gives birth to identical quadruplets.

In genetics and cell biology, cloning refers especially to the DNA sequence, and by implication all the other macromolecules.

Clones in cell lines occur, but there are some obvious provisos. Changes to the DNA in any shape or form means the daughter cells are not identical with the mother cells. Typically during development genes are switched on and off, and the daughter cells gradually become differentiated into mature tissue cells. These are not identical with the original stem cells, so they are clones only in the sense of being derived from the same mother cell.

The laboratory copying of a molecule to produce exact copies is also called cloning.

Species cloned [change]

  • Carp: (1963) In China, embryologist Tong Dizhou produced the world's first cloned fish by inserting the DNA from a cell of a male carp into an egg from a female carp. He published the findings in a Chinese science journal.[2]
  • Mice: (1986) A mouse was the first mammal successfully cloned from an early embryonic cell. Soviet scientists Chaylakhyan, Veprencev, Sviridova, and Nikitin had the mouse "Masha" cloned. Research was published in the journal "Biofizika" volume ХХХII, issue 5 of 1987.[3]
  • Sheep: (1996) From early embryonic cells by Steen Willadsen. Megan and Morag[19] cloned from differentiated embryonic cells in June 1995 and Dolly the sheep from a somatic cell in 1997.[4]
  • Rhesus Macaque: (2000) Tetra, from embryo splitting.[5][6]
  • Gaur: (2001) was the first endangered species cloned.[7]
  • Cattle: Alpha and Beta males 2001 and 2005, Brazil.[8]
  • Cat: CopyCat "CC" (female, late 2001), Little Nicky, 2004, was the first cat cloned for commercial reasons.[9]
  • Dog: (2005) Snuppy, a male Afghan hound was the first cloned dog.[10]
  • Rat: (2003) Ralph, the first cloned rat.[11]
  • Mule: (2003) Idaho Gem, a john mule, was the first horse-family clone.[12]
  • Horse: (2003) Prometea, a Haflinger female, was the first horse clone.[13]
  • Water Buffalo: (2009) Samrupa was the first cloned water buffalo. It was born at India's Karnal National Diary Research Institute but died five days later of a lung infection.[14]
  • Camel: (2009) The first cloned camel.[15]

References [change]

  1. If there is crossing over between the paired chromosomes in the cells leading up to the egg, then the eggs will not be identical.
  2. "Bloodlines timeline". PBS.org. http://www.pbs.org/bloodlines/timeline/text_timeline.html.
  3. "Кто изобрел клонирование?". Archived from the original on 2004-12-23. http://web.archive.org/web/20041223221951/http://www.whoiswho.ru/russian/Curnom/22003/cl.htm. (in Russian)
  4. McLaren A (2000). "Cloning: pathways to a pluripotent future". Science 288 (5472): 1775–80. doi:10.1126/science.288.5472.1775. PMID 10877698.
  5. CNN: Researchers clone monkey by splitting embryo 2000. Retrieved 2008-08-05.
  6. Dean Irvine (2007). "You, again: are we getting closer to cloning humans? - CNN.com". Edition.cnn.com. http://edition.cnn.com/2007/WORLD/europe/11/16/ww.humancloning/index.html?iref=allsearch. Retrieved 2010-08-04.
  7. "First cloned endangered species dies 2 days after birth". CNN. 2001. http://archives.cnn.com/2001/NATURE/01/12/cloned.gaur/index.html. Retrieved April 30, 2010.
  8. Camacho, Keite. Embrapa clona raça de boi ameaçada de extinção. Agência Brasil. 2005 (in Portuguese) Retrieved 2008-08-05
  9. "Americas | Pet kitten cloned for Christmas". BBC News. 2004. http://news.bbc.co.uk/1/hi/world/americas/4120179.stm. Retrieved 2010-08-04.
  10. "First dog clone". News.nationalgeographic.com. http://news.nationalgeographic.com/news/2005/08/photogalleries/dogclone/. Retrieved 2010-08-04.
  11. "Rat called Ralph is latest clone". BBC News. September 25, 2003. http://news.bbc.co.uk/2/hi/science/nature/3136776.stm. Retrieved April 30, 2010.
  12. Associated Press August 25, 2009 (2009-08-25). "Gordon Woods dies at 57; Veterinary scientist helped create first cloned mule". latimes.com. http://www.latimes.com/news/nationworld/nation/la-me-gordon-woods25-2009aug25,0,5372986.story. Retrieved 2010-08-04.
  13. "World's first cloned horse is born - 06 August 2003". New Scientist. http://www.newscientist.com/article/dn4026-worlds-first-cloned-horse-is-born.html. Retrieved 2010-08-04.
  14. Kounteya Sinha, TNN, Feb 13, 2009, 12.33am IST (2009). "India clones world's first buffalo - India - The Times of India". Timesofindia.indiatimes.com. http://timesofindia.indiatimes.com/India-clones-worlds-first-buffalo/articleshow/4120044.cms. Retrieved 2010-08-04.
  15. Spencer, Richard (April 14, 2009). "World's first cloned camel unveiled in Dubai". London: Telegraph.co.uk. http://www.telegraph.co.uk/news/newstopics/howaboutthat/5153780/Worlds-first-cloned-camel-unveiled-in-Dubai.html. Retrieved April 15, 2009.