Understanding how cells interpret the genetic code to synthesize the various proteins our bodies require is leading to the development of new cell-based (stem cell) therapies and corresponding technologies. At present, the best hopes are for treating incurable conditions such as spinal injury, Parkinson's disease and diabetes. Cell-based therapies will play a valuable role in contemporary and future medicine. They will allow a shift toward "personalized medicine" for treatment and prevention of conditions under cellular influence. For example, with just a single prick, a nanotechnology device will quickly measure and analyze 1,000 proteins in a blood droplet (so-called "molecular fingerprinting"). Blood could then serve as a "diagnostic window for disease analysis" as advocated by Leroy Hood of the Institute for Systems Biology. Beyond ethical questions and issues, can you foresee pitfalls and drawbacks in such approaches?