Genetic analysis of patients with nonsyndromic and syndromic retinitis pigmentosa in Puerto Rico: a genetic legacy

Background Retinitis pigmentosa (RP) is a genetically heterogeneous group of diseases characterized by complete progressive vision loss; it has a prevalence of approximately one in 2500-7000. Patients with RP may have isolated findings, or the disorder can occur as part of a constellation of other abnormalities that, together, are known as syndromic RP. The aim of this study was to describe the results of a genetic analysis of a cohort of Puerto Ricans with a clinical diagnosis of RP. Materials and Methods This was a cross-sectional study with a cohort of 224 Puerto Rican patients who carried a clinical diagnosis of RP. During a local (Puerto Rico) RP convention, the patients were offered genetic analysis. Volunteering patients signed consent forms for the study. Saliva samples were obtained and analyzed. Patients were evaluated by at least one of the authors. Patients with pathogenic mutation(s), according to the panel, were classified as positive and sorted based on the results. Results Of 224 patients, 161 (71.9%) had pathogenic gene variants associated with IRDs. 54.5% (122/224) of cases were conclusive. More than half (72/122) of these cases are explained by mutations in the BBS1, PDE6B, CNGB1, and USH2A genes. Genetic analysis showed that the highest rate of pathogenic variants in our cohort was found in the BBS1 gene. Conclusions This was the first genetic analysis in Puerto Rico of patients with RP. The most common mutation associated with RP was found in the BBS1 gene. The frequency of other pathogenic variants related to RP in Puerto Rico were different to those reported in Spain.