Journal of Embryo Transfer (한국수정란이식학회지)

The Korean Society of Embryo Transfer (한국수정란이식학회)
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Factors Affecting the Efficiency of Animal Cloning by Somatic Cell Nuclear Transfer

  • Kim, Min-Goo (Department of Agricultural Biotechnology, Animal Biotechnology Major, and Research Institute for Agriculture and Life Sciences, Seoul National University) ;
  • Park, Chi-Hun (Department of Agricultural Biotechnology, Animal Biotechnology Major, and Research Institute for Agriculture and Life Sciences, Seoul National University) ;
  • Lee, Sang-Goo (Department of Agricultural Biotechnology, Animal Biotechnology Major, and Research Institute for Agriculture and Life Sciences, Seoul National University) ;
  • Seo, Hee-Won (Department of Biological Resources and Technology, and Institute of Biomaterials, Yonsei University) ;
  • Choi, Yo-Han (Department of Biological Resources and Technology, and Institute of Biomaterials, Yonsei University) ;
  • Lee, Chang-Kyu (Department of Agricultural Biotechnology, Animal Biotechnology Major, and Research Institute for Agriculture and Life Sciences, Seoul National University) ;
  • Ka, Hak-Hyun (Department of Biological Resources and Technology, and Institute of Biomaterials, Yonsei University)
  • Published : 2008.06.30
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Abstract

Since the birth of Dolly using fully differentiated somatic cells as a nuclear donor, viable clones were generated successfully in many mammalian species. These achievements in animal cloning demonstrate developmental potential of terminally differentiated somatic cells. At the same time, the somatic cell nuclear transfer (SCNT) technique provides the opportunities to study basic and applied biosciences. However, the efficiency generating viable offsprings by SCNT remains extremely low. There are several explanations why cloned embryos cannot fully develop into viable animals and what factors affect developmental potency of reconstructed embryos by the SCNT technique. The most critical and persuasive explanation for inefficiency in SCNT cloning is incomplete genomic reprogramming, such as DNA methylation and histone modification. Numerous studies on genomic reprogramming demonstrated that incorrect DNA methylation and aberrant epigenetic reprogramming are considerably correlated with abnormal development of SCNT cloned embryos even though its mechanism is not fully understood. The SCNT technique is useful in cloning farm animals because pluripotent stem cells are not established in farm animal species. Therapeutic cloning combined with genetic manipulation will help to control various human diseases. Also, the SCNT technique provides a chance to overcome excessive demand for the organs by production of transgenic animals as xenotransplantation resources. Here, we describe the factors affecting the efficiency of generating cloned farm animals by the SCNT technique and discuss future directions of animal cloning by SCNT to improve the cloning efficiency.

Keywords

References

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