Scientists make stem cell breakthrough
Scientists in the USA have achieved a breakthrough in the development of techniques for generating stem cells to study diseases like MND, thus adding weight to the arguments for pursuing this sometimes controversial area of research.
The researchers describe in the journal “Nature” how they have successfully used a process called somatic cell nuclear transfer (also known as “therapeutic cloning”) to create monkey embryos, from which they have then derived monkey embryonic stem cell lines.
This is the first time that anyone has managed to obtain embryonic stem cells that are genetically identical to a living adult primate (the animal group to which monkeys and humans belong). The process had previously only been achieved in the mouse and some scientists had thought it would never be technically feasible in primates. However, the success of the American researchers establishes “proof of principle” that primate therapeutic cloning is possible.
What is somatic cell nuclear transfer?
This involves removing all of the genetic material (DNA) from an unfertilised egg, in this case a monkey egg. The DNA from an adult cell (generally a skin cell) is then inserted into the egg, before the egg is treated in the laboratory to stimulate it to start developing into an embryo in the normal way. After a few days embryonic stem cells are formed. The genetic make-up of the stem cells is identical to that of the skin cell donor. More information on somatic cell nuclear transfer is available in
Research info sheet Q - Stem cells and MND (1088 kb) . It is important to note that, if carried out with human cells, this process would be used to create embryos for research purposes only; the embryos would never be implanted in a woman and would be destroyed 14 days after the egg had started to divide.
Why are these results important for MND research?
Living human motor neurones affected by MND would provide researchers with an ideal “model” for studying the disease. However, at the moment researchers have to rely on animal models and on brain and spinal cord tissue that people with MND have kindly donated after their death.
Scientists hope that they will eventually be able to encourage human embryonic stem cells to develop into living motor neurones in the lab. If the embryonic stem cells are genetically identical to a person with the rare, inherited form of MND, they will display the effects of the disease and could also be used for testing potential drugs.
Hope for the future
The American researchers did not get as far as actually turning their monkey stem cells into neurones, but they did show that the stem cells could be encouraged to start developing in this way. The success of the American researchers reinforces hopes that scientists will eventually be able to produce motor neurones from cloned human stem cells. Belinda Cupid, Research Manager at the MND Association, said “These important and exciting results add to the scientific arguments for pursuing this controversial area of stem cell research to understand MND.”
In 2004 a Korean scientist claimed to have produced human stem cells through therapeutic cloning, but
his results were later found to be fraudulent and the work was discredited. This time, the American researchers asked independent scientists in Australia to verify that the monkey stem cells really were clones.
Research
