It's not impossible for us to turn white blood cells into stem cells already: Viruses can be harnessed to set the clock back on the cells by delivering genes to them, but that can come with complications, like mutated genes or cancer. Instead, this technique (just published in PLoS One uses plasmids, DNA rings that replicate inside cells, then degrade. By jolting the cells with an electrical pulse, researchers created tiny holes holes in the cells that the plasmids could slip through. The plasmids then inserted genes that cause the white blood cells to change to induced-pluripotent stem cells, or iPS--embryonic-like cells that act as if they were part of a 6-day-old embryo. Unlike other processes, the cells were also introduced into a simulated version of the bone marrow environment they're usually in.