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PURPOSE: To describe the clinical, electrophysiological and genetic spectrum of inherited retinal diseases associated with variants in the PRPH2 gene. METHODS: A total of 241 patients from 168 families across 15 sites in 9 countries with pathogenic or likely pathogenic variants in PRPH2 were included. Records were reviewed for age at symptom onset, visual acuity, full-field ERG, fundus colour photography, fundus autofluorescence (FAF), and SD-OCT. Images were graded into six phenotypes. Statistical analyses were performed to determine genotype-phenotype correlations. RESULTS: The median age at symptom onset was 40 years (range, 4-78 years). FAF phenotypes included normal (5%), butterfly pattern dystrophy, or vitelliform macular dystrophy (11%), central areolar choroidal dystrophy (28%), pseudo-Stargardt pattern dystrophy (41%), and retinitis pigmentosa (25%). Symptom onset was earlier in retinitis pigmentosa as compared with pseudo-Stargardt pattern dystrophy (34 vs 44 years; P = 0.004). The median visual acuity was 0.18 logMAR (interquartile range, 0-0.54 logMAR) and 0.18 logMAR (interquartile range 0-0.42 logMAR) in the right and left eyes, respectively. ERG showed a significantly reduced amplitude across all components (P < 0.001) and a peak time delay in the light-adapted 30-Hz flicker and single-flash b-wave (P < 0.001). Twenty-two variants were novel. The central areolar choroidal dystrophy phenotype was associated with 13 missense variants. The remaining variants showed marked phenotypic variability. CONCLUSIONS: We described six distinct FAF phenotypes associated with variants in the PRPH2 gene. One FAF phenotype may have multiple ERG phenotypes, demonstrating a discordance between structure and function. Given the vast spectrum of PRPH2 disease our findings are useful for future clinical trials.

Background: KCNV2‐associated retinopathy is an autosomal recessive inherited retinal disease classically named cone dystrophy with supernormal rod response (CDSRR). This study aims to identify the best biomarker for evaluating the condition. Methods: A retrospective review of eight patients from seven families with genetically confirmed KCNV2‐associated retinopathy was performed. The best corrected visual acuity (BCVA), full‐field electroretinogram (ffERG), pattern ERG (pERG), fundus imaging: retinal photograph and fundus autofluorescence (FAF), and optical coherence tomography (OCT) were analysed. Results: There was a disproportionate increase in b‐wave amplitude with a relatively small light intensity increase, especially between the two dimmest stimuli of DA 0.002 and 0.01 (−2.7 and −2.0 log cd.s/m2). The a‐wave amplitude was normal. The a‐wave peak time was delayed in all stimuli. The b‐wave peak time was delayed compared to normal, but the gap tightened as intensity increased. The b:a wave ratio was above or at the upper limit for the reference values. FAF bull's eye maculopathy pattern was prominent and variable foveal disruption on OCT was apparent in all patients. Legal blindness was reached before the age of 25. Conclusions: We identified three potential electrophysiology biomarkers to assist in evaluating future therapies: the disproportionate b‐wave amplitude jump, delayed a‐wave and b‐wave peak time, and the higher than normal b:a wave ratio. Any of these biomarkers found with photoreceptor ellipsoid zone foveal‐perifoveal disruption should prompt consideration for KCNV2 retinopathy. The BCVA natural history data suggests the probable optimum therapeutic window in the first three decades of life. [ABSTRACT FROM AUTHOR]

Pulmonary hypoplasia, Diaphragmatic anomalies, Anophthalmia/microphthalmia, and Cardiac defects (PDAC) syndrome is a genetically heterogeneous multiple congenital malformation syndrome. Although pathogenic variants in RARB and STRA6 are established causes of PDAC, many PDAC cases remain unsolved at the molecular level. Recently, we proposed biallelic WNT7B variants as a novel etiology based on several families with typical features of PDAC syndrome albeit with variable expressivity. Here, we report three patients from two families that share a novel founder variant in WNT7B (c.739C > T; Arg247Trp). The phenotypic expression of this variant ranges from typical PDAC features to isolated genitourinary anomalies. Similar to previously reported PDAC‐associated WNT7B variants, this variant was found to significantly impair WNT7B signaling activity further corroborating its proposed pathogenicity. This report adds further evidence to WNT7B‐related PDAC and expands its variable expressivity. [ABSTRACT FROM AUTHOR]

Although eye abnormalities are reported in fetal alcohol spectrum disorders (FASD), no systematic review based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines has been undertaken. Our aim was to document the range and prevalence of eye abnormalities reported in children with prenatal alcohol exposure (PAE) and/or FASD. Searches of electronic databases and manual searches. Eligible articles were observational studies in children with PAE and/or FASD; peer reviewed journal articles in the English language; and studies reporting quantitative or frequency data on functional/structural eye abnormalities. Pooled prevalence, odds ratio, and mean differences were calculated. Of the 1,068 retrieved articles 36 were eligible, including articles on children with diagnosed fetal alcohol syndrome/FASD (N = 31); PAE (N = 3); and FASD or PAE without FASD (N = 2). Structural and functional eye abnormalities were identified, the most prevalent being short palpebral fissure length (66.1%), visual impairment (55.5%), epicanthus (53.5%), subnormal stereoacuity (53.0%), abnormal retinal tortuosity (50.5%), impaired fixation ability (33.3%), telecanthus (31.7%), optic nerve hypoplasia (30.2%), and small optic discs (27.0%). Compared to non-exposed controls, strabismus, subnormal vision, ptosis, short palpebral fissure length, microphthalmos, smaller optic disc area, and retinal vessel tortuosity were more prevalent in children with FASD. Examination of eyes and vision should be considered in children with PAE and suspected or diagnosed FASD to enable early identification and optimal management. This first comprehensive, systematic literature review demonstrates the variety and frequency of eye abnormalities reported in PAE/FASD. [ABSTRACT FROM AUTHOR]