A retrospective cohort study confirmed high phenotypic variability in disease onset and age at which legal blindness is reached in patients with PRPF31-associated Retinitis pigmentosa (RP). The study included cross-sectional data on the phenotype and genotype of patients with PRPF31-associated retinal dystrophy from clinics at the University of Tuebingen and a local database and biobank. Patients underwent ophthalmological and genetic tests. The study included 86 patients who were available for clinical assessment and 111 individuals for whom genomic DNA was available. A total of 53 disease-associate variants were observed in the cohort, with point mutations being the most common class and all but 2 patients exhibiting features typical of RP. The researchers noted that while non-penetrance is commonly documented in family history, it was poorly represented in the study—a possible indication that true asymptomatic mutation carriers are rare if followed up over their lifetime with an ophthalmologic workup.