Somatic Cell Nuclear Transfer (Cloning) Efficiency

Cloning by nuclear transfer from adult somatic cells is a remarkable demonstration of developmental plasticity. When a nucleus is placed in oocyte cytoplasm, the changes in chromatin structure that govern differentiation can be reversed, and the nucleus can be made to control development to term. The overall efficiency of cloning is typically between 0 and 3 % (number of live offspring as a percentage of the number of nuclear transfer embryos), irrespective of the species, the donor cell type or technique. However, this is the cumulative result of losses at each stage of the cloning process. The tables in the PDF provide a summary of the data for each report published by the Data Creators on somatic cell (fetal to adult cells) nuclear transfer up until the time of its compilation, in July 2002. Where the appropriate data was made available, the table provides cloning efficiency for each major stage of the process.