Wilson was one of the most prominent researchers in the nascent field, which sought to put genes into patients to repair their faulty DNA.
Wilson and his colleagues were adding the final patients to a two-year clinical trial, the ultimate goal of which was to treat a rare but devastating disorder. Called OTCD, or ornithine transcarbamylase deficiency, the genetic disorder renders its victims unable to process nitrogen in their blood. Nitrogen is created when protein is broken down, so the blood of OTCD sufferers becomes poisoned when they eat protein-rich foods: One bite of a hot dog can bring on a coma. As a result, just half of children born with OTCD—estimated at roughly one in 80,000 babies in the US, or 50 per year—live to the age of 5. Wilson and his colleagues hoped to treat this disease by giving sufferers a working copy of the defective gene they carry.