Scientists at Geron BioMed, the company launched after a merger between the team that cloned Dolly the sheep at the Roslin Institute in Edinburgh and a stem cell research company in the US, is now concentrating on therapeutic cloning techniques that do not require human egg cells. Cloning in the 'Dolly' way means that a healthy cell is taken from a donor and fused with an egg stripped of its own nucleus - this creates an embryo which is implanted into a surrogate host. Cloning technology in the Dolly sense is what has led to research on human stem cell - those cells which, in their early stages, have the potential to grow into any cells from the human body. These cells, however, have always been extracted from an embryo, so pro-life groups have disagreed with the use of cloning even to help fight disease.
Geron BioMed is, however, now working on techniques that do not require the destruction of human embryos or eggs in such techniques. Simon Best, Geron's managing director, believes it would be possible to achieve the same object by adding the nucleus of an adult cell directly to enucleated embryonic stem cells rather than eggs themselves. If embryonic stem cells were used, the reprogrammed cells would not themselves form an embryo. Instead, they would develop directly into the cells or tissue the appropriate patient needs. The benefit would be that one embryo would have the potential to create many thousands of stem cells, greatly reducing the number of actual embryos sacrificed - limitless supplies of embryonic stem cells could be grown in culture.
Geron BioMed researchers do say that to begin with they will still need to perform cloning using human eggs and embryos, but the prospect that therapeutic cloning could eventually be done without them may lead to an 'easier' future.
Sources and References
The way ahead
Cloning without embryos
New method of cloning could solve ethics issue