Recently U.S. researchers have developed a method for generating "induced pluripotent stem cells" (iPS cells) without the side effects. This new research has shown that iPS cells can be grown using viruses that do not integrate themselves into the hosts' genome, bypassing a problem that has undermined the success of previous iPS cells. This study was done by Matthias Stadtfeld from Massachusetts General Hospital and colleagues.

Before this research, scientists have grown iPS cells that resemble embryonic stem cells, but the process involved introduction of particular DNA-binding proteins to cells via potentially harmful viruses, and often led to alteration in the cells' genomes and caused tumors in animals. But the researchers in the present study have developed a new method that can generate iPs cells without the permanent genetic damage previously associated with their design, and it represents a major step forward in the future application of iPS cells in a clinical setting.

During the recent research, researchers grew their iPS cells. These iPS cells showed potential for growing into a variety of other specialized cells including lung, brain, and heart cells. Researchers claim that they have not observed any unwanted side effects yet.  

Earlier researches have shown that similar reprogrammed cells can alleviate the symptoms of Parkinson's disease and sickle cell anemia in mouse models.

Researchers claim that this new study can lead to advances in cell therapy and treatments of human disease as well. The researchers added that it will be important to determine if human iPS cells generated in the future by this method are as potent as human embryonic stem cells for potential clinical applications.