Gene Therapy...

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Since 1998, when 18-year-old Jesse Gelsinger died in a clinical trial at the University of Pennsylvania, the news on gene therapy hasn't gotten much better. In a recent trial, three children developed leukemia almost certainly brought on by their treatment for X-linked severe combined immunodeficiency (X-SCID). So it's no surprise that there's some trepidation on the part of investors when it comes to companies exploring new gene-altering techniques – the subject of the opening piece of our special feature section on gene therapy.

Still, it's an inescapable fact that gene therapy saved the lives of other children in that same X-SCID trial. Those kinds of results are encouraging for people like Carl June, director of translational research at the Abramson Cancer Center at the University of Pennsylvania, who writes on why cancer gene therapy will be both a medical and financial success. Finally, this...