Cloned cells were transplanted into the brain of mice who suffered from this disease and they replaced sick neurons.

The success of therapeutic cloning in mice. Researchers of the Sloan-Kettering Institute in New York, led by neuro-scientist Lorenz Studer, have treated the guinea pigs suffering from Parkinson with the transplantation of embryonic stem cells obtained from the skin of rodents themselves sick. The experiment, described in Nature Medicine, not only has recorded cases of rejection, but also significant improvements in the evolution of clinical pathology.

The group Studer - after having caused lesions in the brains of mice that would determine the same effects of Parkinson's disease - has transferred the nuclei of cells inside the tail skin cell mouse egg "emptied" of its nucleus, through the technique known as therapeutic cloning (or Scnt, Somatic Cell Nuclear Transfer). The cloned cells, cultivated, were then developed into blastocysts. The researchers thus generated 187 lines of embryonic stem cells from 24 different mice, most of which later differentiate into neurons capable of producing dopamine.