Gene therapy at CHOP allowed a deaf boy to hear. But some deaf people object to the treatment.

An 11-year-old deaf boy is now able to hear in one ear after undergoing a gene therapy treatment at Children’s Hospital of Philadelphia, one of the first such cases in the world. A second boy, aged 3, is scheduled to receive the treatment at CHOP on Friday.

Yet the news has drawn dismay from some who can best appreciate what’s at stake: other deaf people.

For many deaf people, deafness is not something that needs to be fixed. Unlike other medicalconditions that have been treated with gene therapy, deafness is not a disease and it doesn’t deprive someone of a long, rich life. Similar concerns were raised years ago with the invention of cochlear implants, electronic devices that merely approximate the sense of hearing.

But physicians say gene therapy is likely to yield even better results, providing normal or near-normal hearing ability to thousands of people born with rare types of deafness. More than a decade after the first successful gene therapy was tested at CHOP, the technology has come of age, enabling doctors to treat conditions from...