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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
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