Purpose:RPGRIP1 encodes a ciliary protein expressed in the photoreceptor connecting cilium. Mutations in this gene cause ∼5% of Leber congenital amaurosis (LCA) worldwide, but are also associated with cone–rod dystrophy (CRD) and retinitis pigmentosa (RP) phenotypes. Our purpose was to clinically characterize RPGRIP1 patients from our cohort, collect clinical data of additional RPGRIP1 patients reported previously in the literature, identify common clinical features, and seek genotype–phenotype correlations.Methods: Clinical data were collected from 16 patients of our cohort and 212 previously reported RPGRIP1 patients and included (when available) family history, best corrected visual acuity (BCVA), refraction, comprehensive ocular examination, optical coherence tomography (OCT) imaging, visual fields (VF), and full-field electroretinography (ffERG).Results: Out of 228 patients, the majority (197, 86%) were diagnosed with LCA, 18 (7%) with RP, and 13 (5%) with CRD. Age of onset was during early childhood (n = 133, average of 1.7 years). All patients but 6 had moderate hyperopia (n = 59, mean of 4.8D), and average BCVA was 0.06 Snellen (n = 124; only 10 patients had visual acuity [VA] > 0.10 Snellen). On funduscopy, narrowing of blood vessels was noted early in life. Most patients had mild bone spicule-like pigmentation starting in the midperiphery and later encroaching upon the posterior pole. OCT showed thinning of the outer nuclear layer (ONL), while cystoid changes and edema were relatively rare. VF were usually very constricted from early on. ffERG responses were non-detectable in the vast majority of cases. Most of the mutations are predicted to be null (363 alleles), and 93 alleles harbored missense mutations. Missense mutations were identified only in two regions: the RPGR-interacting domain and the C2 domains. Biallelic null mutations are mostly associated with a severe form of the disease, whereas biallelic missense mutations usually cause a milder disease (mostly CRD).Conclusion: Our results indicate that RPGRIP1 biallelic mutations usually cause severe retinal degeneration at an early age with a cone–rod pattern. However, most of the patients exhibit preservation of some (usually low) BCVA for a long period and can potentially benefit from gene therapy. Missense changes appear only in the conserved domains and are associated with a milder phenotype.

<p>El desarrollo de la Genética Humana ha puesto a disposición de la Medicina potentes recursos para investigar los cambios en el material genético subyacentes a diversas enfermedades en pacientes individuales y sus familias. Semejante capacidad diagnóstica suele exceder en mucho a la capacidad de brindar una terapéutica específica, por lo que su utilidad médica reside en el perfeccionamiento del diagnóstico, la estimación del pronóstico clínico, y el cálculo del riesgo de recurrencia para futuros hermanos e hijos de un paciente dado; el paciente y/o su familia, por su parte, suelen buscar en el diagnóstico genético una certeza que les permita limitar su ansiedad. En Pediatría, el consenso mayoritario es que en los niños se justifica la investigación genética diagnóstica, que la investigación predictiva puede hacerse si la afección investigada permite una intervención médicamente beneficiosa durante la niñez, y que la del estado de portación debe diferirse hasta que el paciente alcance un cierto grado de madurez y competencia. El propósito de este trabajo es plantear los aspectos bioéticos y legales relacionados con la investigación de una familia que está segregando una mutación para adrenoleucodistrofia ligada al X, en la que por diversas circunstancias se estudió a menores de edad. Se discute la naturaleza de la enfermedad, el hecho de que tres de los individuos estudiados eran menores de edad, el rol proactivo de los padres en el proceso de toma de decisiones conducente a la investigación de tales miembros, y la existencia de un marco legal específico para la intervención.</p>