Teenager Dies While Undergoing Experimental Gene Therapy

An 18-year-old from Arizona has died after receiving gene therapy to treat a rare genetic disease called ornithine transcarbamylase deficiency. Jesse Gelsinger died of failure of his liver and other internal organs four days after researchers at the University of Pennsylvania infused a genetically modified adenovirus into the liver, but the death has not yet been firmly linked to the treatment.

At last count, 313 gene therapy experiments have been approved by federal authorities and more than 2,500 people have undergone treatments without apparent harm--but also without major benefits. Critics have charged that Gelsinger’s death was needless, however, because he suffered from a mild form of the genetic disorder and had it under control with drugs and diet.

--Compiled by Times medical writer Thomas H. Maugh II