UNASSIGNED: A multi-stakeholder, patient centric approach will be critical to the design of future successful clinical trials with outcome measures relevant to the RDH12-IRD population.

UNASSIGNED: To investigate the causal effect of elevated blood pressure on primary open-angle glaucoma (POAG) and POAG endophenotypes.
UNASSIGNED: Two-sample Mendelian randomization (MR) was performed to investigate the causal effect of elevated systolic blood pressure (SBP) (N = 757,601) and diastolic blood pressure (DBP) (N = 757,601) on intraocular pressure (IOP) (N = 139,555), macular retinal nerve fiber layer (mRNFL) thickness (N = 33,129), ganglion cell complex (GCC) thickness (N = 33,129), vertical cup-to-disc ratio (VCDR) (N = 111,724), and POAG liability (Ncases = 16,677, Ncontrols = 199,580). The primary analysis was conducted using the inverse-variance weighted approach. Sensitivity analyses were performed to investigate robustness to horizontal pleiotropy, winner\'s curse, and collider bias. Multivariable MR was performed to investigate whether any effect of blood pressure on retinal ganglion cell degeneration was mediated through increased IOP.
UNASSIGNED: Increased genetically predicted SBP and DBP associated with an increase in IOP (0.17 mm Hg [95% CI = 0.11 to 0.24] per 10 mm Hg higher SBP, P = 5.18 × 10-7, and 0.17 mm Hg [95% CI = 0.05 to 0.28 mm Hg] per 10 mm Hg higher DBP, P = 0.004). Increased genetically predicted SBP associated with a thinner GCC (0.04 µm [95% CI = -0.07 to -0.01 µm], P = 0.018) and a thinner mRNFL (0.04 µm [95% CI = -0.07 to -0.01 µm], P = 0.004), an effect that arises independently of IOP according to our mediation analysis. Neither SBP nor DBP associated with VCDR or POAG liability.
UNASSIGNED: These findings support a causal effect of elevated blood pressure on retinal ganglion cell degeneration that does not require intermediary changes in IOP. Targeted blood pressure control may help preserve vision by lowering IOP and, independently, by preventing retinal ganglion cell degeneration, including in individuals with a normal IOP.

UNASSIGNED: To define the clinical characteristics of centrosomal protein 290 (CEP290)-associated inherited retinal degeneration (IRD) and determine which assessments may provide reliable endpoints in future interventional trials.
UNASSIGNED: Participants in this natural history study were enrolled into 2 best-corrected visual acuity (BCVA) cohorts: light perception to > 1.0 logarithm of the minimum angle of resolution (logMAR) and 1.0 logMAR to 0.4 logMAR. Each comprised 4 age cohorts (3-5, 6-11, 12-17, and ≥ 18 years).
UNASSIGNED: Patients with CEP290-associated IRD caused by the intron 26 c.2991+1655A>G mutation and BCVA ranging from light perception to 0.4 logMAR.
UNASSIGNED: Best-corrected visual acuity, full-field stimulus threshold (FST) sensitivity, Ora-Visual Navigation Challenge (Ora-VNC) composite score, and OCT-outer nuclear layer (OCT-ONL) average thickness were assessed at screening, baseline, 3 months, 6 months, and 12 months.
UNASSIGNED: Best-corrected visual acuity, FST sensitivity, Ora-VNC composite score, and OCT-ONL average thickness.
UNASSIGNED: Twenty-six participants were included in this analysis. Nineteen were female. All participants were White and 4 reported Hispanic ethnicity. At screening, 13 of 16 adult and 9 of 10 pediatric participants had BCVA > 1.0 logMAR. Baseline BCVA was variable (median [range] = 2.0 [0.5, 3.9] logMAR) and was uncorrelated with age, as were VNC composite score, FST sensitivity, and OCT-ONL average thickness. Mean (95% confidence interval [CI]) test-retest variability was -0.04 (-0.09, 0.01) logMAR for BCVA (n = 25); 0.6 (-0.1, 1.3) for VNC composite score (n = 18); and 0.10 (-0.07, 0.27) log cd.s/m2 for red FST (n = 14). A greater than expected test-retest variability (5 [0, 10] μm, n = 14) was observed for OCT-ONL average thickness as nystagmus impacted ability to repeat measures at the same retinal location. Functional assessments were stable over 12 months. Mean (95% CI) change from baseline was 0.06 (-0.17, 0.29) logMAR for BCVA (n = 23); -0.1 (-1.2, 1.0) for VNC composite score (n = 21); and -0.15 (-0.43, 0.14) log cd.s/m2 for red FST (n = 16).
UNASSIGNED: Vision was stable over 12 months. Best-corrected visual acuity, FST, and VNC composite score are potentially viable endpoints for future studies in CEP290-associated IRD. Repeatability of OCT measures poses challenges for quantifying anatomical changes in this population.
UNASSIGNED: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

OBJECTIVE: Gyrate atrophy of the choroid and retina (GACR) is an autosomal recessive inherited metabolic disorder (IMD) characterised by progressive retinal degeneration, leading to severe visual impairment. The rapid developments in ophthalmic genetic therapies warrant knowledge on clinical phenotype of eligible diseases such as GACR to define future therapeutic parameters in clinical trials.
METHODS: Retrospective chart analysis was performed in nineteen patients. Data were analysed using IBM SPSS Statistics version 28.0.1.1.
RESULTS: Nineteen patients were included with a mean age of 32.6 years (range 8-58). Mean age at onset of ophthalmic symptoms was 7.9 years (range 3-16). Median logMAR of visual acuity at inclusion was 0.26 (range -0.18-3.00). Mean age at cataract surgery was 28.8 years (n = 11 patients). Mean spherical equivalent of the refractive error was -8.96 (range -20.87 to -2.25). Cystoid maculopathy was present in 68% of patients, with a loss of integrity of the foveal ellipsoid zone (EZ) in 24/38 eyes. Of the 14 patients treated with dietary protein restriction, the four patients who started the diet before age 10 showed most benefit.
CONCLUSIONS: This study demonstrates the severe ophthalmic disease course associated with GACR, as well as possible benefit of early dietary treatment. In addition to visual loss, patients experience severe myopia, early-onset cataract, and CME. There is a loss of foveal EZ integrity at a young age, emphasising the need for early diagnosis enabling current and future therapeutic interventions.

Humans have a highly developed retina and obtain approximately 80% of their external information from vision. Photoreceptor cells, which are located in the outermost layer of the neuroretina and recognize light signals, are highly specialized sensory cilia that share structural and functional features with primary cilia. Genetic disorders of the retina or photoreceptor cells are termed inherited retinal diseases (IRDs) and are caused by variants in one of more than 280 genes identified to date. Among the genes responsible for IRDs, many are shared with those responsible for ciliopathies. In studies of inherited diseases, mouse models are commonly used due to their advantages in breeding, handling, and relative feasibility in creating pathological models. On the other hand, structural, functional, and genetic differences in the retina between mice and humans can be a barrier in IRD research. To overcome the limitations of mouse models, larger vertebrate models of IRDs can be a useful research subject. In particular, canines have retinas that are structurally and functionally similar and eyes that are anatomically comparable to those of humans. In addition, due to their unique veterinary clinical surveillance and genetic background, naturally occurring canine IRDs are more likely to be identified than in other large animals. To date, pathogenic mutations related to canine IRDs have been identified in more than 30 genes, contributing to the understanding of pathogeneses and to the development of new therapies. This review provides an overview of the roles of the canine IRD models in ciliopathy research.

Retinitis pigmentosa (RP) is a heterogeneous disease and the main cause of vision loss within the group of inherited retinal diseases (IRDs). IRDs are a group of rare disorders caused by mutations in one or more of over 280 genes which ultimately result in blindness. Modifier genes play a key role in modulating disease phenotypes, and mutations in them can affect disease outcomes, rate of progression, and severity. Our previous studies have demonstrated that the nuclear hormone receptor 2 family e, member 3 (Nr2e3) gene reduced disease progression and loss of photoreceptor cell layers in RhoP23H-/- mice. This follow up, pharmacology study evaluates a longitudinal NR2E3 dose response in the clinically relevant heterozygous RhoP23H mouse. Reduced retinal degeneration and improved retinal morphology was observed 6 months following treatment evaluating three different NR2E3 doses. Histological and immunohistochemical analysis revealed regions of photoreceptor rescue in the treated retinas of RhoP23H+/- mice. Functional assessment by electroretinogram (ERG) showed attenuated photoreceptor degeneration with all doses. This study demonstrates the effectiveness of different doses of NR2E3 at reducing retinal degeneration and informs dose selection for clinical trials of RhoP23H-associated RP.

BACKGROUND: Diabetic retinopathy (DR) is both a microangiopathy and a neurodegenerative disease. However, the connections between both changes are not well known.
OBJECTIVE: To characterise the longitudinal retinal ganglion cell layer + inner plexiform layer (GCL + IPL) changes and their association with microvascular changes in type-2 diabetes (T2D) patients with nonproliferative diabetic retinopathy (NPDR).
METHODS: This two-year prospective study (CORDIS, NCT03696810) included 122 T2D individuals with NPDR identified as risk phenotypes B and C, which present a more rapid progression. Phenotype C was identified by decreased VD ≥ 2SD in healthy controls, and phenotype B, identified by subclinical macular oedema with only minimal vascular closure. The GCL + IPL thickness, vessel density, perfusion density and area of intercapillary spaces (AIS) were assessed by optical coherence tomography (OCT) and OCT angiography (OCTA). Linear mixed effects models were employed to evaluate the retinal GCL + IPL progression and its associations.
RESULTS: Regarding GCL + IPL thickness, T2D individuals presented on average 80.1 ± 7.49 μm, statistically significantly lower than the healthy control group, 82.5 ± 5.71 (p = 0.022), with only phenotype C differing significantly from controls (p = 0.006). GCL + IPL thickness steadily decreased during the two-year period in both risk phenotypes, with an annual decline rate of -0.372 μm/year (p < 0.001). Indeed, phenotype C showed a higher rate of progression (-0.459 μm/year, p < 0.001) when compared to phenotype B (-0.296 μm/year, p = 0.036). Eyes with ETDRS grade 20 showed GCL + IPL thickness values comparable to those of healthy control group (83.3 ± 5.80 and 82.7 ± 5.50 μm, respectively, p = 0.880), whereas there was a progressive decrease in GCL + IPL thickness in ETDRS grades 35 and 43-47 associated with the increase in severity of the retinopathy (-0.276 μm/year, p = 0.004; -0.585 μm/year, p = 0.013, respectively). Furthermore, the study showed statistically significant associations between the progressive thinning of GCL + IPL and the progressive increase in retinal capillary non-perfusion, with particular relevance for AIS (p < 0.001).
CONCLUSIONS: Our findings showed that, in eyes with NPDR and at risk for progression, retinal neurodegeneration occurs at different rates in different risk phenotypes, and it is associated with retinal microvascular non-perfusion.

(1) Background: NR2E3 encodes a nuclear receptor transcription factor that is considered to promote cell differentiation, affect retinal development, and regulate phototransduction in rods and cones. This study aimed to analyze the clinical characteristics and observe the prognosis of autosomal dominant retinopathy (ADRP) and autosomal recessive retinopathy (ARRP) associated with NR2E3; (2) Methods: NR2E3 variants were collected from our exome sequencing data and identified per the American College of Medical Genetics and Genomics criteria. Data from our cohort and a systemic literature review were conducted to explore the NR2E3 variants spectrum and potential genotype-phenotype correlations; (3) Results: Nine pathogenic variants/likely pathogenic variants in NR2E3, including five novel variants, were detected in eight families (four each with ADRP and ARRP). Follow-up data showed schisis/atrophy in the macula and retinal degeneration initiation around the vascular arcades with differences in ADRP and ARRP. A systemic literature review indicated patients with ADRP presented better visual acuity (p < 0.01) and later onset age (p < 0.0001) than did those with ARRP; (4) Conclusions: Macular schisis and retinal degeneration around vascular arcades may present as the prognosis of NR2E3-retinopathy, dominant, or recessive. Our data might further enrich our understanding of NR2E3 variants and associated inherited retinopathy.

OBJECTIVE: Late-onset Stargardt disease is a subtype of Stargardt disease type 1 (STGD1), defined by an age of onset of 45 years or older. We describe the disease characteristics, underlying genetics, and disease progression of late-onset STGD1 and highlight the differences from geographic atrophy.
METHODS: Retrospective cohort study.
METHODS: Seventy-one patients with late-onset STGD1.
METHODS: Medical files were reviewed for clinical data including age at onset, initial symptoms, and best-corrected visual acuity. A quantitative and qualitative assessment of retinal pigment epithelium (RPE) atrophy was performed on fundus autofluorescence images and OCT scans.
METHODS: Age at onset, genotype, visual acuity, atrophy growth rates, and loss of external limiting membrane, ellipsoid zone, and RPE.
RESULTS: Median age at onset was 55.0 years (range, 45-82 years). A combination of a mild and severe variant in ATP-binding cassette subfamily A member 4 (ABCA4) was the most common genotype (n = 49 [69.0%]). The most frequent allele, c.5603A→T (p.Asn1868Ile), was present in 43 of 71 patients (60.6%). No combination of 2 severe variants was found. At first presentation, all patients have flecks. Foveal-sparing atrophy was present in 33.3% of eyes, whereas 21.1% had atrophy with foveal involvement. Extrafoveal atrophy was present in 38.9% of eyes, and no atrophy was evident in 6.7% of eyes. Time-to-event curves showed a median duration of 15.4 years (95% confidence interval, 11.1-19.6 years) from onset to foveal involvement. The median visual acuity decline was -0.03 Snellen decimal per year (interquartile range [IQR], -0.07 to 0.00 Snellen decimal; 0.03 logarithm of the minimum angle of resolution). Median atrophy growth was 0.590 mm2/year (IQR, 0.046-1.641 mm2/year) for definitely decreased autofluorescence and 0.650 mm2/year (IQR, 0.299-1.729 mm2/year) for total decreased autofluorescence.
CONCLUSIONS: Late-onset STGD1 is a subtype of STGD1 with most commonly 1 severe and 1 mild ABCA4 variant. The general patient presents with typical fundus flecks and retinal atrophy in a foveal-sparing pattern with preserved central vision. Misdiagnosis as age-related macular degeneration should be avoided to prevent futile invasive treatments with potential complications. In addition, correct diagnosis lends patients with late-onset STGD1 the opportunity to participate in potentially beneficial therapeutic trials for STGD1.
BACKGROUND: The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Mutations in the photoreceptor-specific tetraspanin gene peripherin-2 (PRPH2) lead to widely varying forms of retinal degeneration ranging from retinitis pigmentosa to macular dystrophy. Both inter- and intra-familial phenotypic heterogeneity has led to much interest in uncovering the complex pathogenic mechanisms of PRPH2-associated disease. Majority of disease-causing mutations in PRPH2 reside in the second intradiscal loop, wherein seven cysteines control protein folding and oligomerization. Here, we utilize knockin models to evaluate the role of three D2 loop cysteine mutants (Y141C, C213Y and C150S), alone or in combination. We elucidated how these mutations affect PRPH2 properties, including oligomerization and subcellular localization, and contribute to disease processes. Results from our structural, functional and molecular studies revealed that, in contrast to our understanding from prior investigations, rods are highly affected by PRPH2 mutations interfering with oligomerization and not merely by the haploinsufficiency associated with these mutations. On the other hand, cones are less affected by the toxicity of the mutant protein and significantly reduced protein levels, suggesting that knockdown therapeutic strategies may sustain cone functionality for a longer period. This observation provides useful data to guide and simplify the current development of effective therapeutic approaches for PRPH2-associated diseases that combine knockdown with high levels of gene supplementation needed to generate prolonged rod improvement.