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Purpose: Autoimmune retinopathy (AIR) is a poorly characterized disease with a wide phenotypic spectrum, complicating investigations of its underlying pathophysiology. We sought to analyze optical coherence tomography (OCT) retinal thickness changes in AIR patients., Methods: A retrospective chart review from 2007 to 2017 was performed evaluating AIR patients at a single academic, tertiary referral center. OCT retinal sublayer analysis was performed, and paradoxical thickening phenotypes were reviewed., Results: Twenty-nine AIR patients with positive anti-retinal antibodies and OCT imaging were identified. Overall, AIR patients had thinner retinal sublayers compared to controls; however, 12 patients (41.4%) had paradoxical thickening of the outer plexiform layer (OPL). This revealed two distinct OCT phenotypes. No association was found between retinal sublayer thickness and specific antiretinal antibodies., Conclusions: While the pathogenicity of antiretinal antibodies remains unclear, the OCT phenotypes observed underscore the potential for identifying clues in the underlying disease processes and clinical diagnosis.

Renowned French painter Edgar Degas suffered of progressive light sensitivity and blurred central vision in both eyes, which affected his life and art in many ways. A first cousin from his mother's side, Estelle Musson of New Orleans also lost vision in a similar fashion at a comparable age. We postulated that Edgar and Estelle shared the same retinal pathology that possibly developed in a hereditary fashion, and we were interested whether any of their living family descendants might carry ABCA4 mutations to test the possibility that Edgar Degas may have had Stargardt disease.Edgar was never married and had no children, but Estelle had five children, four of whom from her marriage to Edgar's younger brother, and there are several descendants still living in New Orleans area. Genetic testing on five of Estelle's great grandchildren (Edgar's great grandnieces) were performed searching for ABCA4 mutations.We could not document any disease-causing variations in the ABCA4 gene in any of the descendants and therefore concluded that Edgar Degas most likely did not have Stargardt disease. Estelle and Edgar may have shared a different hereditary disease or have had two different retinal dystrophies or had another eye disease, including the unlikely possibility of inflammatory disease.

Purpose: Age-related macular degeneration (AMD) is a devastating disease characterized by central vision impairment in individuals with advanced age. Neovascular AMD is a form of end-stage disease in which choroidal vessel outgrowth occurs beneath the retina. While many hypotheses have been raised as to what triggers the formation of pathological choroidal neovascular membranes, the exact mechanism for their initiation remains unresolved. Polymorphisms in the FLT1 gene have previously been associated with neovascular AMD risk, including the rs9943922 single nucleotide polymorphism (SNP). Here, we aimed to determine the association between the high-risk FLT1 genotype and FLT1 protein levels in human retina or retinal pigment epithelium (RPE)/choroid tissue., Methods: Retina and RPE/choroid tissue from 10 human donor eyes was selected from a collection of eyes genotyped for the rs9943922 SNP. Differences in soluble and membrane bound FLT1 protein levels were assessed for retina versus RPE/choroid donor tissue using ELISA and Western blotting analyses. Genotype-associated changes in FLT1 protein levels were also evaluated., Results: We found soluble FLT1 levels in the RPE/choroid tissue to be approximately three times higher than that of the retina (p < 0.001), while both samples have similar levels of the membrane bound form. When tissue with the rs9943922 SNP was compared with controls, no significant genotypic differences in FLT1 protein levels were observed., Conclusions: Based on these data, we conclude that the rs9943922 SNP in the FLT1 gene does not result in a large difference in FLT1 protein levels, regardless of whether it is the soluble or the membrane bound form.

Background: In a four-generation Caucasian family variably diagnosed with autosomal dominant (AD) Stickler or Wagner disease, commercial gene screening failed to identify a mutation in COL2A1 or VCAN. We utilized linkage mapping and exome sequencing to identify the causal variant., Materials and Methods: Genomic DNA samples collected from 40 family members were analyzed. A whole-genome linkage scan was performed using Illumina HumanLinkage-24 BeadChip followed by two-point and multipoint linkage analyses using FASTLINK and MERLIN. Exome sequencing was performed on two affected individuals, followed by co-segregation analysis., Results: Parametric multipoint linkage analysis using an AD inheritance model demonstrated HLOD scores > 2.00 at chromosomes 1p36.13-1p36.11 and 12q12-12q14.1. SIMWALK multipoint analysis replicated the peak in chromosome 12q (peak LOD = 1.975). FASTLINK two-point analysis highlighted several clustered chromosome 12q SNPs with HLOD > 1.0. Exome sequencing revealed a novel nonsense mutation (c.115C>T, p.Gln39*) in exon 2 of COL2A1 that is expected to result in nonsense-mediated decay of the RNA transcript. This mutation co-segregated with all clinically affected individuals and seven individuals who were clinically unaffected., Conclusions: The utility of combining traditional linkage mapping and exome sequencing is highlighted to identify gene mutations in large families displaying a Mendelian inheritance of disease. Historically, nonsense mutations in exon 2 of COL2A1 have been reported to cause a fully penetrant ocular-only Stickler phenotype with few or no systemic manifestations. We report a novel nonsense mutation in exon 2 of COL2A1 that displays incomplete penetrance and/or variable age of onset with extraocular manifestations.

Purpose: To phenotypically and genotypically characterize a large Puerto Rican kindred with X-linked retinitis pigmentosa associated with a novel RP GTPase regulator (RPGR) genotype., Methods: A total of 100 family members of a single kindred with X-linked RP were evaluated with ophthalmic examinations and blood DNA analysis. Visual fields, OCT, and full-field ERG were obtained on all affected males and carriers., Results: Of the 100 family members examined, 13 were affected males and 18 were carriers. A deletion of 2 base pair of the RPGR gene in the ORF15 region at position c.2267-2268 (Lys756del2aaAG hemi) was identified with the affected and carriers. Best eye visual acuity was correlated with age (Spearman coefficient = 0.95) with hand-motion acuity by age 35 and light perception to no light perception by age 50-60. Visual fields were minimally plottable by age 40, and ERG responses reached non-detectable levels by late teens. Carriers had no or mild visual symptoms. All carriers had visual acuity of at least 20/50 or better in one eye, and the amount of retinal degeneration was variable with ERG responses ranging from severely impaired to normal., Conclusions: Profound visual loss occurred by the second decade of life with progression to near no light perception by age 60 in this kindred of X-linked RP associated with the RPGR genotype. Female carriers maintained visual acuity with age and were identifiable by clinical and ERG examination. The information from this study is important to determine the optimal age for intervention, as new RP treatments are being developed and tested.

Purpose: To determine the role of the single nucleotide polymorphism (SNP) (rs613872) in the TCF4 gene in Fuchs endothelial corneal dystrophy (FECD) in patients from Iowa., Methods: A cohort of 82 patients with FECD and 163 normal control subjects from Iowa were genotyped at the SNP rs613872 using a real-time allelic discrimination assay., Results: The frequencies of the alleles of rs613872 were compared between FECD patients and control subjects. A highly significant association (p-value = 2.96 × 10(-10)) was detected between this SNP and FECD. Comparison of the genotypes of SNP rs613872 between FECD patients and control subjects produced a p-value of 2.43 × 10(-10)., Conclusion: Prior reports have shown that SNP rs613872 in the TCF4 gene is highly associated with FECD. Our study confirms this association and shows that the TCF4 gene has an important role in the pathogenesis of corneal disease in patients from Iowa.

Purpose: Copy number variations (duplications) of TANK binding kinase 1 (TBK1) have been associated with normal tension glaucoma (NTG), a common cause of blindness worldwide. Mutations in other genes involved in autophagy (TLR4 and OPTN) have been associated with NTG. Here we report searching for additional proteins involved in autophagy that may also have roles in NTG., Materials and Methods: HEK-293T cells were transfected to produce synthetic TBK1 protein with FLAG and S tags. Proteins that associate with TBK1 were isolated from HEK-293T lysates using tandem affinity purification (TAP) and polyacrylamide gel electrophoresis (PAGE). Isolated proteins were identified with mass spectrometry. A cohort of 148 NTG patients and 77 controls from Iowa were tested for glaucoma-causing mutations in genes that encode identified proteins that interact with TBK1 using high resolution melt (HRM) analysis and DNA sequencing., Results: TAP studies show that three proteins expressed in HEK-293T cells (NAP1, TANK and TBKBP1) interact with TBK1. Testing cohorts of NTG and normal controls for disease-causing mutations in TANK, identified a total of nine unique variants including three non-synonymous changes, one synonymous changes and five intronic changes. When analyzed alone or as a group, the non-synonymous TBK1 coding sequence changes were not associated with either NTG or primary open angle glaucoma., Conclusion: TAP showed that NAP1, TANK and TBKBP1 interact with TBK1 and are good candidates for contributing to NTG. A mutation screen of TANK detected three non-synonymous variants. Although, it remains possible that one or more of these TANK mutations may have a role in NTG, the data in this report do not provide statistical support for an association between TANK variants and NTG.

Objective: To determine the role of the SLC4A11 gene in two pedigrees affected with autosomal recessive congenital hereditary endothelial dystrophy (CHED)., Methods: Nine members of a pedigree from the Kingdom of Saudi Arabia (pedigree 971G) and 2 twins in a pedigree from Bosnia (pedigree GGO413) were diagnosed with autosomal recessive CHED and contributed DNA samples for genetic studies. The proband of each pedigree was tested for disease-causing mutations in the SLC4A11 gene with bi-directional DNA sequencing. Screening assays using restriction enzyme digests were developed to test a cohort of 99 normal control subjects for the presence of SLC4A11 mutations., Results: A novel, homozygous mutation in the SLC4A11 gene (Thr271Met) was detected in the proband of pedigree 971G. Homozygous Thr271Met mutations were detected in all affected members of pedigree 971G. The Thr271Met mutation was not detected in a cohort of 99 normal control subjects. This mutation alters a highly conserved amino acid in the encoded SLC4A11 protein. No SLC4A11 mutations were detected in pedigree GGO413., Conclusion: A novel SLC4A11 mutation (Thr271Met) is associated with autosomal recessive CHED in a pedigree from the Kingdom of Saudi Arabia and provides additional support that mutations in this gene cause disease.

Leber Hereditary Optic Neuropathy (LHON) is a maternally inherited blinding disease caused by missense mutations in the mitochondrial DNA (mtDNA). However, incomplete penetrance and a predominance of male patients presenting with vision loss suggest that modifying factors play an important role in the development of the disease. Evidence from several studies suggests that both nuclear modifier genes and environmental factors may be necessary to trigger the optic neuropathy in individuals harboring an LHON-causing mtDNA mutation. Recently, an optic neuropathy susceptibility locus at Xp21-Xq21 has been reported. In this study, we performed X-chromosomal linkage analysis in a large Brazilian family harboring a homoplasmic G11778A mtDNA mutation on a haplogroup J background. We report the identification of a novel LHON susceptibility locus on chromosome Xq25-27.2, with multipoint non-parametric linkage scores of > 5.00 (P = 0.005) and a maximum two-point non-parametric linkage score of 10.12, (P = 0.003) for marker DXS984 (Xq27.1). These results suggest genetic heterogeneity for X-linked modifiers of LHON.

Purpose: To determine whether retinal dysfunction in obligate carriers of the Bardet-Biedl syndrome (BBS) could be observed in local electroretinographic responses obtained with the multifocal electroretinogram (mfERG)., Methods: Six obligate carriers of the BBS were examined for the study. Examination of each carrier included an ocular examination and mfERG testing of one eye. For the mfERG, we used a 103-scaled hexagonal stimulus array that subtended a retinal area of approximately 40 degrees in diameter. The amplitudes and implicit times in each location for the mfERG were compared with the corresponding values determined for a group of 34 normally sighted, age-similar control subjects., Results: Mapping of 103 local electroretinographic response amplitudes within a central 40 degrees area with the mfERG showed regions of reduced mfERG amplitudes in three of six carriers. Implicit time measurements in the 6 carriers were all normal except for those locations associated with abnormal amplitude reductions in 3 of the carriers. When present, retinal dysfunction was evident in the presence of a normal-appearing fundus., Conclusions: Multifocal ERG testing can demonstrate areas of retinal dysfunction in carriers of the BBS. This test may therefore be useful for identifying some heterozygous carriers of this disease.

Objective: To identify the genetic factors associated with familial non-arteritic anterior ischemic optic neuropathy (NA-AION) in a large pedigree., Methods: Eleven family members of a single pedigree, including six affected with NA-AION, underwent detailed clinical examinations. The mitochondrial DNA of the proband was sequenced in its entirety in search of disease-causing mutations associated with NA-AION in the pedigree. A control panel comprising 1488 patients suspected of having Leber hereditary optic neuropathy (LHON) and 97 general-population control subjects was screened for the mitochondrial sequence variant identified in the family., Results: Affected family members were all male and exhibited classic features of NA-AION. Their mean age was 50.2 +/- 5.0 years. A total of 23 sequence variations were detected in the mitochondrial genome of the proband, including one novel sequence variation (G4132A, Ala276Thr) in the NADH dehydrogenase subunit 1 gene (ND1). The G4132A mitochondrial variant was detected in six members of a single pedigree with NA-AION. The G4132A variation was not observed in any of the 1585 subjects in the control panel. Moreover, this variant was not identified in over 2469 ethnically diverse individuals previously evaluated through the Human Mitochondrial Genome Database. None of the three major mutations associated with LHON (G3460A, G11778A, T14484C) were identified in the family., Conclusion: The G4132A mitochondrial variation is associated with familial NA-AION in our pedigree.

Purpose: To report a new phenotype in retinitis pigmentosa (RP) patients with CRB1 mutations at the RP12 locus., Patients: Thirty-seven patients from two Pakistani families with severe retinitis pigmentosa., Methods: Samples were screened with single-strand conformation polymorphism analysis followed by DNA sequencing of the coding sequence of the CRB1 gene., Results: Two novel CRB1 mutations were discovered. No patients had evidence of preservation of the para-arteriolar retinal pigment epithelium (PPRPE) that has been previously reported in all cases of RP associated with CRB1 mutations., Conclusions: Patients with severe autosomal recessive (or simplex) RP who lack the finding of PPRPE should not be excluded from molecular analysis of CRB1 purely because they lack the clinical feature of PPRPE. This report illustrates that RP at the RP12 locus is not clinically uniform. The absence of PPRPE cannot be used to exclude CRB1 as a potential molecular explanation for RP.

Congenital hereditary endothelial dystrophy (CHED) is a disorder of the corneal endothelium and has been recognized to segregate in families with both autosomal dominant (AD) and autosomal recessive (AR) modes of transmission. AD-CHED has been previously linked to the pericentric region of chromosome 20. Posterior polymorphous dystrophy (PPMD), a corneal endothelial disorder showing phenotypic overlap with CHED, has also been previously genetically mapped to this region. The genetic interval containing AD-CHED is within the larger genetic interval containing the PPMD locus. This study sought to determine whether AR-CHED segregating in a consanguineous Saudi Arabian pedigree is linked to the previously mapped and overlapping loci for AD-CHED and PPMD on the pericentric region of chromosome 20. Forty members of a consanguineous Saudi Arabian pedigree segregating AR-CHED were ascertained. Short tandem-repeat polymorphic markers from the 20 cM interval on chromosome 20 containing both the PPMD and AD-CHED loci were used to genotype these individuals. LOD score analysis of the genotype data with the MENDEL software package utilizing a model of autosomal recessive inheritance with complete penetrance showed exclusion of CHED from the entire PPMD/AD-CHED interval by utilizing overlapping intervals of LOD scores of at least -2. The results obtained demonstrate that AR-CHED is not allelic to either AD-CHED or PPMD, although it has been proposed that AD-CHED may be allelic to PPMD. Thus, there are at least two genes responsible for CHED and PPMD.

Purpose: The RHO C110Y mutation has been recently reported to cause a phenotypically unspecified form of autosomal dominant retinitis pigmentosa (adRP). The study of a family affected with this mutation allowed us to hereby describe the genotype/phenotype correlation associated with the RHO C110Y mutation., Methods: A six-generation pedigree cosegregating adRP and RHO C110Y in ten accessible individuals was ophthalmologically investigated. All family members affected with RP went through complete eye examination and ERG testing., Results: The disease first manifested with nyctalopia during adulthood and slowly progressed over the next decades towards tubular visual field defects and relatively preserved central vision. Ophthalmoscopically, the fundus remained almost unaltered until the end of the third decade of life, and then slowly progressed towards typical RP changes with minimal macular involvement by the eighth decade. Color vision remained unaltered. Earliest ERG alteration was limited to the rod system followed by a rod-cone pattern. Scotopic and photopic ERG were recordable until the fourth and sixth decades, respectively., Discussion: RHO C110Y-associated adRP is characterized by a late onset and a mild progression compatible with type 2 or regional RP with little intrafamilial phenotypic variability and complete penetrance. Characterization of genotype-phenotype correlations plays a role in the improvement of genetic and prognostic counselling.

Thirty-one members of a family affected with X-linked ocular albinism (OA1) were studied to characterize the clinical phenotype and identify the disease-causing mutation. The family members were examined with ophthalmoscopy, electroretinography, and Goldmann perimetry. Linkage analysis was performed with markers from the OA1 locus. Exons 2 and 8 of the OA1 gene were assayed with the polymerase chain reaction (PCR). The six affected males had visual acuities ranging from 20/40 to 20/200. All had nystagmus, iris transillumination, and foveal hypoplasia. The eldest affected male had 20/40 vision and was asymptomatic. The level of the visual acuity of the affected males was not related to the degree of retinal pigmentation. All seven female carriers had normal visual function but were found to have iris transillumination defects and variable retinal pigmentary appearance ranging from minimal pigmentary disturbance, patchy and diffuse hypopigmentation, to classic 'mud-splattered' appearance. Linkage analysis was consistent with a disease-causing mutation at the OA1 locus. PCR analysis revealed a deletion which includes at least the portion of the OA1 gene between exons 2 and 8. Affected males with X-linked ocular albinism can have a visual disability that ranges from almost none to legal blindness, and the female carriers can have variable retinal pigmentary appearance. Mutation screening of the OA1 gene can be used to confirm the diagnosis in isolated males of some families, and genetic linkage analysis can be used to accurately identify carriers even when the specific mutation cannot be identified.

The objective of this study was to fully characterize the macular dystrophy phenotype and genotype in a large family of the Zermatt area of Switzerland. Clinical and molecular studies of the family included a comprehensive eye examination and a mutational analysis of the RDS, rhodopsin, and TIMP-3 genes. In selected cases, fluorescein angiography, perimetry, and electroretinography were performed. Forty-two family members at risk of expressing the maculopathy were studied. Of these, 24 were found to be clinically affected. The severity of macular disease in these patients was clearly age-related and different stages of progression were identified. Central pigmentary alterations were seen in adolescent patients, while patients in their late teens and twenties exhibited drusen-like deposits. Later, these defects formed focal areas of atrophy which eventually led to central geographic atrophy with severe visual loss by the fifth decade and cone-rod dysfunction. The transmission of this condition is autosomal dominant with complete penetrance. The underlying genetic defect is a mutation in codon 172 of the RDS/peripherin gene, a gene expressed in both rods and cones, which results in the substitution of tryptophan for an arginine residue at that position. 'Zermatt macular dystrophy' is a dominant, age-related, progressive macular dystrophy which in later stages resembles atrophic age-related macular degeneration. The size of the family studied allowed definition of the clinical spectrum of this condition and identification of the related genetic defect which allows more precise diagnosis and counseling.