The number of individuals tested for ORF15 seemed to reduce after the introduction of whole genome sequencing (2019).<h4>Conclusions</h4>We identified an estimated 977 living patients with <i>RPGR</i>-associated XLRP from 2594 tested individuals, representing a large absolute number and significant population who could benefit from emerging gene therapy, with prevalence higher than other treatable inherited retinal dystrophies. The gene discussed is RPGR; the disease is Retinal dystrophy.