Similar techniques to those used to clone Dolly the Sheep have been used to create a human embryo for stem cell research.
Dolly was created as a clone from another adult sheep using somatic cell nuclear transfer.
The new technique involves removing a cell nucleus from a skin cell and transplanting it into an unfertilised egg with its own nucleus also intact. This results in the egg having three sets of chromosomes, as opposed to the two sets which would normally occur. However, it is potentially safer than chemically created stem cells which can be prone to develop cancer.
The cloned egg then divides in the same way as a normal human embryo, reaching the stage where it has divided into a 100 cell structure. Stem cells can then be harvested from the microscopic embryo.
It was previously not known whether the technique was transferable to humans. Previous attempts to create human skin cell clones involved removing the nucleus from the egg to give the cell two sets of chromosomes, but this was not successful. A cell with three copies of chromosomes would result in Down’s Syndrome in a normal embryo.
The researchers pointed out that the research only proves that a human egg can be used to transform an adult cell into a stem cell, but there was more work to be done.
Professor Mary Herbert, of Newcastle University’s Institute for Ageing and Health, added: “While this approach does not in itself provide a solution, it takes us a step closer to understanding where the problems lie.”