The world's first gene therapy surgery for a rare retinal illness was conducted in Naples at the University of Campania's Ophthalmology Clinic "Luigi Vanvitelli". It is Usher syndrome type 1B, an inherited condition that affects the retina and inner ear and is thought to afflict approximately 20,000 people in the United States and Europe. The proportion may be understated, however, because it is difficult to diagnose and not all nations, such as Italy, fund genetic testing. These children are born deaf and gradually lose their sight over the first decade of life. Deafness can be treated surgically, but increasing vision loss and blindness cannot be cured. In Naples, 50 patients were selected and monitored for the next five years to better understand the disease's progression and investigate all of the unknowns. This allowed the Neapolitan team to design the world's first clinical study.