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Purpose: To report patient acceptance and safety of repeated intravitreal injections of anti-VEGF agents for exudative AMD, by retina specialists, without an eye examination before every injection. Methods: Retrospective chart review. 115 eyes (110 patients) with exudative AMD underwent repeated intravitreal anti-VEGF injections with limited interval examination and diagnostic testing. Medication, laterality, number of injection cycles started and completed, number of injections per injection cycle, subjective visual changes, pre- and post-injection visual acuity (VA), pre- and post-injection intraocular pressure (IOP), nurse- and patient-initiated phone calls, emergency (non-scheduled) clinic visits, complications, new diagnoses, and patient complaints after each injection were recorded. The main outcome measures were complications and patient complaints. Results: 396 injections were administered in the injection clinic to 110 patients in 175 injection cycles (range: 0 to 5 injections per cycle). Of 175 injection cycles, there were 134 uninterrupted cycles and 41 interrupted cycles where an eye exam was performed. Fourteen new diagnoses were made: six during emergency visits, three at injection clinic appointments, and five at the next full examination after completion of a prescribed injection clinic cycle. Conclusions: Administration of anti-VEGF injections in a designated injection clinic, by retina specialists, according to a prescribed schedule, and with limited pre-injection testing, for patients with wet AMD, is well-tolerated. [ABSTRACT FROM AUTHOR]

Purpose/objectives: to evaluate new onset uveitis or reactivated uveitis by biologic agents and characterize their features., Materials and Methods: This is a multicenter, retrospective case series. Patients under biologic therapy were included if they developed uveitis for the first time or experienced intraocular inflammation which was different in location or laterality to previous inflammation., Results: Sixteen patients were identified. The underlying disorders included ankylosing spondylitis, juvenile idiopathic arthritis, rheumatoid arthritis, and Behçet's Disease. The biologic agents associated with a first episode of uveitis (n = 11) or with a new recurrence of uveitis (n = 5) were etanercept, adalimumab, abatacept, infliximab, and golimumab. Sarcoidosis based on bihilar lymphadenopathy, other computer tomography-findings, or biopsy was diagnosed in five patients under therapy with etanercep, adalimumab, and abatacept. Additionally, seven patients developed clinical changes in their uveitis pattern, suggesting sarcoid uveitis., Conclusions: Biologic treatment-induced uveitis often presents as granulomatous disease.

Purpose: To characterize inheritance, penetrance, and trinucleotide repeat expansion stability in Fuchs endothelial corneal dystrophy (FECD)., Methods: One thousand unrelated and related subjects with and without FECD were prospectively recruited. CTG18.1 repeat length (CTG18.1L) was determined via short tandem repeat assay and Southern blotting of leukocyte DNA. Multivariable logistic regression and generalized estimating equation models were employed., Results: There were 546 unrelated FECD cases (67.6% female; 70 ± 10 years) and 235 controls (63.8% female; 73 ± 8 years; all ≥ 50 years). CTG18.1 expansion (CTG18.1exp+) was observed in 424 (77.7%) cases and 18 (7.7%) controls (P = 2.48 × 10-44). CTG18.1 expansion was associated with FECD severity (P = 5.62 × 10-7). The family arm of the study included 331 members from 112 FECD-affected families; 87 families were CTG18.1exp+. Autosomal dominant inheritance with variable expression of FECD was observed, regardless of expansion status. FECD penetrance of CTG18.1 expansion increased with age, ranging from 44.4% in the youngest (19-46 years) to 86.2% in the oldest (64-91 years) age quartiles. Among 62 parent-offspring transmissions of CTG18.1exp+, 48 (77.4%) had a change in CTG18.1L ≤ 10 repeats, and eight (12.9%) were ≥50 repeats, including five large expansions (∼1000-2000 repeats) that contracted. Among 44 offspring who did not inherit the CTG18.1exp+ allele, eight (18.2%) exhibited FECD., Conclusions: CTG18.1 expansion was highly associated with FECD but demonstrated incomplete penetrance. CTG18.1L instability occurred in a minority of parent-offspring transmissions, with large expansions exhibiting contraction. The observation of FECD without CTG18.1 expansion among family members in CTG18.1exp+ families highlights the complexity of the relationship between the FECD phenotype and CTG18.1 expansion.

Purpose: Alpha lipoic acid (ALA) is a nutraceutical and potent antioxidant that has shown efficacy in the retina light damage mouse model and in humans for multiple sclerosis. Our objective was to evaluate the efficacy and safety of oral ALA for the treatment of geographic atrophy (GA)., Design: Randomized, controlled, double-masked, multicenter phase 2 clinical trial of ALA versus placebo., Participants: Participants with unilateral or bilateral GA from age-related macular degeneration., Methods: Participants were randomized to 1200 mg daily of ALA or placebo. Fundus autofluorescence, fundus color photography, and spectral-domain OCT were conducted and best-corrected visual acuity (BCVA) was obtained at baseline and every 6 months through month 18., Main Outcome Measures: Annual rate of change over 18 months in square root-transformed area of GA in study eyes as measured on fundus autofluorescence. Secondary outcomes included the number of adverse events (AEs), change in BCVA, and annual rate of change in area of GA measured on color photographs., Results: Fifty-three participants (mean age, 80 years) were randomized (April 2016-August 2017). Twenty-seven participants (37 eyes) were in the placebo group, and 26 participants (36 eyes) were in the ALA group. Unadjusted mean (standard error) annual change in GA area was 0.28 (0.02) mm and 0.31 (0.02) mm for the placebo and ALA groups, respectively (difference, 0.04 mm; 95% confidence interval [CI], -0.03 to 0.11 mm; P = 0.30). Adjusting for baseline GA area, number of GA lesions, and presence of subfoveal GA, the mean annual change in GA area was 0.27 (0.04) mm and 0.32 (0.05) mm for the placebo and ALA groups, respectively (difference, 0.05 mm; 95% CI, -0.02 to 0.12 mm; P = 0.14). At 18 months, the percent of eyes losing 15 letters or more of BCVA was 22% (8 of 36) and 14% (5 of 36) in the placebo and ALA groups, respectively (P = 0.54). No difference was found in the percentage of participants with nonserious AEs (P = 0.96) or serious AEs (P = 0.28) between the placebo and ALA groups., Conclusions: Results do not support ALA having beneficial effects on GA or BCVA. This trial design may be useful for other GA repurposing drug trials., (Copyright © 2020 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

The encapsulation of small hydrophilic molecules and response to specific biological triggers in a controlled manner have become two of the significant challenges in biomedical research, in particular in the field of localized drug delivery and biosensing. This work reports the fabrication of free-standing microchamber array films made of biodegradable polymers for the encapsulation and enzymatically triggered release of small hydrophilic molecules. Polycaprolactone (PCL) microchamber arrays were demonstrated to fully biodegrade within 5 hours of exposure to lipase from Pseudomonas cepacia (lipase PS) at a concentration of 0.5 mg ml-1, with lower concentrations producing correspondingly longer degradation times. The gradual process of deterioration was real-time monitored utilising laser Fraunhofer diffraction patterns. Additionally, a small hydrophilic molecule, 5(6)-carboxyfluorescein (CF), was loaded into the PCL microchamber arrays in a dry state; however, the substantial permeability of the PCL film led to leakage of the dye molecules. Consequently, polylactic acid (PLA) was blended with PCL to reduce its permeability, enabling blended PCL-PLA (1 : 2 ratio correspondingly) microchamber arrays to trap the small hydrophilic molecule CF. PCL-PLA (1 : 2) microchamber arrays hold potential for controlled release under the catalysis of lipase within 26 hours. Additionally, it is calculated that approximately 11 pg of CF dye crystals was loaded into individual microchambers of 10 μm size, indicating that the microchamber array films could yield a highly efficient encapsulation.

[This corrects the article DOI: 10.1371/journal.pone.0025598.].

Neurodegenerative diseases affecting the macula constitute a major cause of incurable vision loss and exhibit considerable clinical and genetic heterogeneity, from early-onset monogenic disease to multifactorial late-onset age-related macular degeneration (AMD). As part of our continued efforts to define genetic causes of macular degeneration, we performed whole exome sequencing in four individuals of a two-generation family with autosomal dominant maculopathy and identified a rare variant p.Glu1144Lys in Fibrillin 2 (FBN2), a glycoprotein of the elastin-rich extracellular matrix (ECM). Sanger sequencing validated the segregation of this variant in the complete pedigree, including two additional affected and one unaffected individual. Sequencing of 192 maculopathy patients revealed additional rare variants, predicted to disrupt FBN2 function. We then undertook additional studies to explore the relationship of FBN2 to macular disease. We show that FBN2 localizes to Bruch's membrane and its expression appears to be reduced in aging and AMD eyes, prompting us to examine its relationship with AMD. We detect suggestive association of a common FBN2 non-synonymous variant, rs154001 (p.Val965Ile) with AMD in 10 337 cases and 11 174 controls (OR = 1.10; P-value = 3.79 × 10(-5)). Thus, it appears that rare and common variants in a single gene--FBN2--can contribute to Mendelian and complex forms of macular degeneration. Our studies provide genetic evidence for a key role of elastin microfibers and Bruch's membrane in maintaining blood-retina homeostasis and establish the importance of studying orphan diseases for understanding more common clinical phenotypes., (Published by Oxford University Press 2014. This work is written by (a) US Government employee(s) and is in the public domain in the US.)

Objective: To determine whether genotypes at 2 major loci associated with late age-related macular degeneration (AMD), complement factor H (CFH) and age-related maculopathy susceptibility 2 (ARMS2), influence the relative benefits of Age-Related Eye Disease Study (AREDS) supplements., Design: Unplanned retrospective evaluation of a prospective, randomized, placebo-controlled clinical trial of vitamins and minerals for the treatment of AMD., Subjects: AREDS participants (mean age, 69 years) who were at risk of developing late AMD and who were randomized to the 4 arms of AREDS supplement treatment., Methods: Analyses were performed using the Cox proportional hazards model to predict progression to late AMD (neovascular or central geographic atrophy). Statistical models, adjusted for age, gender, smoking status, and baseline AMD severity, were used to examine the influence of genotypes on the response to therapy with 4 randomly assigned arms of AREDS supplement components: placebo, antioxidants (vitamin C, vitamin E, β-carotene), zinc, or a combination., Main Outcome Measures: The influence of the genotype on the relative treatment response to the randomized components of the AREDS supplement, measured as progression to late AMD., Results: Of the 1237 genotyped AREDS participants of white ethnicity, late AMD developed in 385 (31.1%) during the mean follow-up of 6.6 years. As previously demonstrated, CFH genotype (P = 0.005), ARMS2 (P< 0.0001), and supplement were associated individually with progression to late AMD. An interaction analysis found no evidence that the relative benefits of AREDS supplementation varied by genotype. Analysis of (1) CFH rs1061170 and rs1410996 combined with ARMS2 rs10490924 with the 4 randomly assigned arms of AREDS supplement and (2) analysis of the combination of CFH rs412852 and rs3766405 with ARMS2 c.372&#95;815del443ins54 with the AREDS components resulted in no interaction (P = 0.06 and P = 0.45, respectively, before multiplicity adjustment)., Conclusions: The AREDS supplements reduced the rate of AMD progression across all genotype groups. Furthermore, the genotypes at the CFH and ARMS2 loci did not statistically significantly alter the benefits of AREDS supplements. Genetic testing remains a valuable research tool, but these analyses suggest it provides no benefits in managing nutritional supplementation for patients at risk of late AMD., (Copyright © 2014 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Snowflake Vitreoretinal Degeneration (SVD) is associated with the R162W mutation of the Kir7.1 inwardly-rectifying potassium channel. Kir7.1 is found at the apical membrane of Retinal Pigment Epithelial (RPE) cells, adjacent to the photoreceptor neurons. The SVD phenotype ranges from RPE degeneration to an abnormal b-wave to a liquid vitreous. We sought to determine how this mutation alters the structure and function of the human Kir7.1 channel. In this study, we expressed a Kir7.1 construct with the R162W mutation in CHO cells to evaluate function of the ion channel. Compared to the wild-type protein, the mutant protein exhibited a non-functional Kir channel that resulted in depolarization of the resting membrane potential. Upon co-expression with wild-type Kir7.1, R162W mutant showed a reduction of IKir7.1 and positive shift in '0' current potential. Homology modeling based on the structure of a bacterial Kir channel protein suggested that the effect of R162W mutation is a result of loss of hydrogen bonding by the regulatory lipid binding domain of the cytoplasmic structure.

Age-related macular degeneration (AMD) is a common cause of blindness in older individuals. To accelerate the understanding of AMD biology and help design new therapies, we executed a collaborative genome-wide association study, including >17,100 advanced AMD cases and >60,000 controls of European and Asian ancestry. We identified 19 loci associated at P < 5 × 10(-8). These loci show enrichment for genes involved in the regulation of complement activity, lipid metabolism, extracellular matrix remodeling and angiogenesis. Our results include seven loci with associations reaching P < 5 × 10(-8) for the first time, near the genes COL8A1-FILIP1L, IER3-DDR1, SLC16A8, TGFBR1, RAD51B, ADAMTS9 and B3GALTL. A genetic risk score combining SNP genotypes from all loci showed similar ability to distinguish cases and controls in all samples examined. Our findings provide new directions for biological, genetic and therapeutic studies of AMD.

KCNJ13 encodes Kir7.1, an inwardly rectifying K(+) channel that is expressed in multiple ion-transporting epithelia. A mutation in KCNJ13 resulting in an arginine-to-tryptophan change at residue 162 (R162W) of Kir7.1 was associated with snowflake vitreoretinal degeneration, an inherited autosomal-dominant disease characterized by vitreous degeneration and mild retinal degeneration. We used the Xenopus laevis oocyte expression system to assess the functional properties of the R162W (mutant) Kir7.1 channel and determine how wild-type (WT) Kir7.1 is affected by the presence of the mutant subunit. Recordings obtained via the two-electrode voltage-clamp technique revealed that injection of oocytes with mutant Kir7.1 cRNA resulted in currents and cation selectivity that were indistinguishable from those in water-injected oocytes, suggesting that the mutant protein does not form functional channels in the plasma membrane. Coinjection of oocytes with equal amounts of mutant and WT Kir7.1 cRNAs resulted in inward K(+) and Rb(+) currents with amplitudes that were ∼17% of those in oocytes injected with WT Kir7.1 cRNA alone, demonstrating a dominant-negative effect of the mutant subunit. Similar to oocytes injected with WT Kir7.1 cRNA alone, coinjected oocytes exhibited inwardly rectifying Rb(+) currents that were more than seven times larger than K(+) currents, indicating that mutant subunits did not alter Kir7.1 channel selectivity. Immunostaining of Xenopus oocytes or Madin-Darby canine kidney cells expressing mutant or WT Kir7.1 demonstrated distribution of both proteins primarily in the plasma membrane. Our data suggest that the R162W mutation suppresses Kir7.1 channel activity, possibly by negatively impacting gating by membrane phosphadidylinositol 4,5-bisphosphate.

The authors performed a systematic review of the association of complement component 2(C2)/complement factor B (CFB) gene polymorphisms with age-related macular degeneration (AMD). In total, data from 19 studies published between 2006 and 2011 were pooled for 4 polymorphisms: rs9332739 and rs547154 in the C2 gene and rs4151667 and rs641153 in the CFB gene. Data extraction and assessments for risk of bias were independently performed by 2 reviewers. Allele frequencies and allele and genotypic effects were pooled. Heterogeneity and publication bias were explored. Pooled minor allele frequencies for all 4 SNPs were between 4.7% and 9.6% for all polymorphisms, except for an Indian population in which the C allele at rs9332739 was the major allele. For the C2 polymorphisms, the minor C allele at rs9332739 and the minor T allele at rs547154 carried estimated relative risks (odds ratios) of 0.55 (95% confidence interval (CI): 0.46, 0.65) and 0.47 (95% CI: 0.39, 0.57), respectively. For the CFB polymorphisms, the minor A alleles at rs4151667 and rs614153 carried estimated risks of 0.54 (95% CI: 0.45, 0.64) and 0.41 (95% CI: 0.34, 0.51), respectively. These allele effects contributed to an absolute lowering of the risk of all AMD in Caucasian populations by 2.0%-6.0%. This meta-analysis provides a robust estimate of the protective association of C2/CFB with AMD.

Fuchs endothelial corneal dystrophy (FECD) is a common, familial disease of the corneal endothelium and is the leading indication for corneal transplantation. Variation in the transcription factor 4 (TCF4) gene has been identified as a major contributor to the disease. We tested for an association between an intronic TGC trinucleotide repeat in TCF4 and FECD by determining repeat length in 66 affected participants with severe FECD and 63 participants with normal corneas in a 3-stage discovery/replication/validation study. PCR primers flanking the TGC repeat were used to amplify leukocyte-derived genomic DNA. Repeat length was determined by direct sequencing, short tandem repeat (STR) assay and Southern blotting. Genomic Southern blots were used to evaluate samples for which only a single allele was identified by STR analysis. Compiling data for 3 arms of the study, a TGC repeat length >50 was present in 79% of FECD cases and in 3% of normal controls cases (p<0.001). Among cases, 52 of 66 (79%) subjects had >50 TGC repeats, 13 (20%) had <40 repeats and 1 (2%) had an intermediate repeat length. In comparison, only 2 of 63 (3%) unaffected control subjects had >50 repeats, 60 (95%) had <40 repeats and 1 (2%) had an intermediate repeat length. The repeat length was greater than 1000 in 4 FECD cases. The sensitivity and specificity of >50 TGC repeats identifying FECD in this patient cohort was 79% and 96%, respectively Expanded TGC repeat was more specific for FECD cases than the previously identified, highly associated, single nucleotide polymorphism, rs613872 (specificity = 79%). The TGC trinucleotide repeat expansion in TCF4 is strongly associated with FECD, and a repeat length >50 is highly specific for the disease This association suggests that trinucleotide expansion may play a pathogenic role in the majority of FECD cases and is a predictor of disease risk.

Purpose: To determine the contribution of copy number variation (CNV) in the regulation of complement activation (RCA) locus to the development of age-related macular degeneration (AMD)., Methods: A multiplex ligation-dependent probe amplification assay was developed to quantify the number of copies of CFH, CFHR3, CFHR1, CFHR4, CFHR2, and CFHR5 in humans. Subjects with (451) and without (362) AMD were genotyped using the assay, and the impact on AMD risk was evaluated., Results: Eight unique combinations of copy number variation were observed in the 813 subjects. Combined deletion of CFHR3 and CFHR1 was protective (OR=0.47, 95% confidence interval 0.36-0.62) against AMD and was observed in 88 (82 [18.6%] with one deletion, 6 [1.4%] with two deletions) subjects with AMD and 127 (108 [30.7%] with one deletion, 19 [5.4%] with two deletions) subjects without AMD. Other deletions were much less common: CFH intron 1 (n=2), CFH exon 18 (n=2), combined CFH exon 18 and CFHR3 (n=1), CFHR3 (n=2), CFHR1 (n=1), combined CFHR1 and CFHR4 (n=15), and CFHR2 deletion (n=7, 0.9%). The combined CFHR3 and CFHR1 deletion was observed on a common protective haplotype, while the others appeared to have arisen on multiple different haplotypes., Conclusions: We found copy number variations of CFHR3, CFHR1, CFHR4, and CFHR2. Combined deletion of CFHR3 and CFHR1 was associated with a decreased risk of developing AMD. Other deletions were not sufficiently common to have a statistically detectable impact on the risk of AMD, and duplications were not observed.

Complement factor H shows very strong association with Age-related Macular Degeneration (AMD), and recent data suggest that multiple causal variants are associated with disease. To refine the location of the disease associated variants, we characterized in detail the structural variation at CFH and its paralogs, including two copy number polymorphisms (CNP), CNP147 and CNP148, and several rare deletions and duplications. Examination of 34 AMD-enriched extended families (N = 293) and AMD cases (White N = 4210 Indian = 134; Malay = 140) and controls (White N = 3229; Indian = 117; Malay = 2390) demonstrated that deletion CNP148 was protective against AMD, independent of SNPs at CFH. Regression analysis of seven common haplotypes showed three haplotypes, H1, H6 and H7, as conferring risk for AMD development. Being the most common haplotype H1 confers the greatest risk by increasing the odds of AMD by 2.75-fold (95% CI = [2.51, 3.01]; p = 8.31×10(-109)); Caucasian (H6) and Indian-specific (H7) recombinant haplotypes increase the odds of AMD by 1.85-fold (p = 3.52×10(-9)) and by 15.57-fold (P = 0.007), respectively. We identified a 32-kb region downstream of Y402H (rs1061170), shared by all three risk haplotypes, suggesting that this region may be critical for AMD development. Further analysis showed that two SNPs within the 32 kb block, rs1329428 and rs203687, optimally explain disease association. rs1329428 resides in 20 kb unique sequence block, but rs203687 resides in a 12 kb block that is 89% similar to a noncoding region contained in ΔCNP148. We conclude that causal variation in this region potentially encompasses both regulatory effects at single markers and copy number.

Purpose: To present genome-wide association analyses of genotypic and environmental risks on age-related macular degeneration (AMD) using 593 subjects from the age-related eye disease study (AREDS), after adjusting for population stratification and including questionable controls., Methods: Single nucleotide polymorphism (SNP) associations with AMD for the non-Hispanic white population were investigated using a log-additive model after adjusting for population stratification. Replication of possible SNP-disease association was performed by genotyping an independent group of 444 AMD case and 300 control subjects. Logistic regression models were used to assess interaction effects between smoking and SNPs associated with AMD. Independent genetic risk effects among the disease-associated SNPs were also investigated using multiple logistic regression models., Results: Population stratification was observed among the individuals having a self-reported race of non-Hispanic white. Risk allele frequencies at established AMD loci demonstrated that questionable control subjects were similar to control subjects in the AREDS, suggesting that they could be used as true controls in the analyses. Genetic loci (complement factor H [CFH], complement factor B [CFB], the age-related maculopathy susceptibility 2 locus containing the hypothetical gene [LOC387715]/the high-temperature requirement A-1 [HTRA1], and complement component 3 [C3]) that were already known to be associated with AMD were identified. An additional 26 novel SNPs potentially associated with AMD were identified, but none were definitely replicated in a second independent group of subjects. Smoking did not interact with known AMD loci, but was associated with late AMD. Statistically independent genetic signals were observed within the Pleckstrin homology domain-containing family A member 1 (PLEKHA1) region near LOC387715/HTRA1 and within a haplotype spanning exon 19 of the C3 gene., Conclusions: Population stratification among Caucasian subjects from the multicentered AREDS was observed, suggesting that it should be adjusted for in future studies. The AREDS questionable control subjects can be used as control subjects in the AREDS genome-wide association study (GWAS). Smoking was an independent risk factor for advanced AMD in the AREDS subjects. There continues to be evidence that the 10q26 (age-related maculopathy susceptibility 2 gene [ARMS2]) locus spanning PLEKHA1-LOC387715-HTRA1 and the C3 gene may contain multiple independent genetic risks contributing to AMD.

First syntheses of a deuterium-labeled very long C34-containing polyunsaturated fatty acid, C34:5n5.d(2), and three other unlabeled very long chain C30-32-containing polyunsaturated fatty acids are reported here. These syntheses were achieved by coupling chemically modified C22- and C20-containing polyunsaturated fatty acids with carbanions derived from arylalkyl sulfones, followed by sodium amalgam-mediated desulfonylation.

Background: Fuchs's corneal dystrophy (FCD) is a leading cause of corneal transplantation and affects 5% of persons in the United States who are over the age of 40 years. Clinically visible deposits called guttae develop under the corneal endothelium in patients with FCD. A loss of endothelial cells and deposition of an abnormal extracellular matrix are observed microscopically. In advanced disease, the cornea swells and becomes cloudy because the remaining endothelial cells are not sufficient to keep the cornea dehydrated and clear. Although rare genetic variation that contributes to both early-onset and typical late-onset forms of FCD has been identified, to our knowledge, no common variants have been reported., Methods: We performed a genomewide association study and replicated the most significant observations in a second, independent group of subjects., Results: Alleles in the transcription factor 4 gene (TCF4), encoding a member of the E-protein family (E2-2), were associated with typical FCD (P=2.3x10(-26)). The association increased the odds of having FCD by a factor of 30 for persons with two copies of the disease variants (homozygotes) and discriminated between case subjects and control subjects with about 76% accuracy. At least two regions of the TCF4 locus were associated independently with FCD. Alleles in the gene encoding protein tyrosine phosphatase receptor type G (PTPRG) were associated with FCD (P=4.0x10(-7)), but the association did not reach genomewide significance., Conclusions: Genetic variation in TCF4 contributes to the development of FCD. (Funded by the National Eye Institute and others.)

Retinal pigment epithelium (RPE) is a polarized cell layer critical for photoreceptor function and survival. The unique physiology and relationship to the photoreceptors make the RPE a critical determinant of human vision. Therefore, we performed a global expression profiling of native and cultured human fetal and adult RPE and determined a set of highly expressed 'signature' genes by comparing the observed RPE gene profiles to the Novartis expression database (SymAtlas: http://wombat.gnf.org/index.html) of 78 tissues. Using stringent selection criteria of at least 10-fold higher expression in three distinct preparations, we identified 154 RPE signature genes, which were validated by qRT-PCR analysis in RPE and in an independent set of 11 tissues. Several of the highly expressed signature genes encode proteins involved in visual cycle, melanogenesis and cell adhesion and Gene ontology analysis enabled the assignment of RPE signature genes to epithelial channels and transporters (ClCN4, BEST1, SLCA20) or matrix remodeling (TIMP3, COL8A2). Fifteen RPE signature genes were associated with known ophthalmic diseases, and 25 others were mapped to regions of disease loci. An evaluation of the RPE signature genes in a recently completed AMD genomewide association (GWA) data set revealed that TIMP3, GRAMD3, PITPNA and CHRNA3 signature genes may have potential roles in AMD pathogenesis and deserve further examination. We propose that RPE signature genes are excellent candidates for retinal diseases and for physiological investigations (e.g. dopachrome tautomerase in melanogenesis). The RPE signature gene set should allow the validation of RPE-like cells derived from human embryonic or induced pluripotent stem cells for cell-based therapies of degenerative retinal diseases.

We executed a genome-wide association scan for age-related macular degeneration (AMD) in 2,157 cases and 1,150 controls. Our results validate AMD susceptibility loci near CFH (P < 10(-75)), ARMS2 (P < 10(-59)), C2/CFB (P < 10(-20)), C3 (P < 10(-9)), and CFI (P < 10(-6)). We compared our top findings with the Tufts/Massachusetts General Hospital genome-wide association study of advanced AMD (821 cases, 1,709 controls) and genotyped 30 promising markers in additional individuals (up to 7,749 cases and 4,625 controls). With these data, we identified a susceptibility locus near TIMP3 (overall P = 1.1 x 10(-11)), a metalloproteinase involved in degradation of the extracellular matrix and previously implicated in early-onset maculopathy. In addition, our data revealed strong association signals with alleles at two loci (LIPC, P = 1.3 x 10(-7); CETP, P = 7.4 x 10(-7)) that were previously associated with high-density lipoprotein cholesterol (HDL-c) levels in blood. Consistent with the hypothesis that HDL metabolism is associated with AMD pathogenesis, we also observed association with AMD of HDL-c-associated alleles near LPL (P = 3.0 x 10(-3)) and ABCA1 (P = 5.6 x 10(-4)). Multilocus analysis including all susceptibility loci showed that 329 of 331 individuals (99%) with the highest-risk genotypes were cases, and 85% of these had advanced AMD. Our studies extend the catalog of AMD associated loci, help identify individuals at high risk of disease, and provide clues about underlying cellular pathways that should eventually lead to new therapies.

The major focus of our research is to understand how age-related macular degeneration (AMD) develops. It is known that genetic variation can explain much of the risk of developing AMD. However, we do not know what controls the transition between a normal fundus and the extensive accumulation of subretinal inflammatory material that we recognize as drusen in AMD. We do know that the accumulation of this inflammatory material that characterizes the maculopathy underlying AMD is by far the most important predictor of late AMD. Late or advanced forms of AMD include geographic atrophy in which there is patchy death of the retina and exudation in which abnormal neovascularization invades the subretinal or subretinal pigment epithelial space. Thus, preventing the accumulation of the inflammatory debris underneath the retina could be expected to alleviate much of the vision loss from this devastating disease.

Activation of the alternative pathway of complement is implicated in common neurodegenerative diseases including age-related macular degeneration (AMD). We explored the impact of common variation in genes encoding proteins of the alternative pathway on complement activation in human blood and in AMD. Genetic variation across the genes encoding complement factor H (CFH), factor B (CFB) and component 3 (C3) was determined. The influence of common haplotypes defining transcriptional and translational units on complement activation in blood was determined in a quantitative genomic association study. Individual haplotypes in CFH and CFB were associated with distinct and novel effects on plasma levels of precursors, regulators and activation products of the alternative pathway of complement in human blood. Further, genetic variation in CFH thought to influence cell surface regulation of complement did not alter plasma complement levels in human blood. Plasma markers of chronic activation (split-products Ba and C3d) and an activating enzyme (factor D) were elevated in AMD subjects. Most of the elevation in AMD was accounted for by the genetic variation controlling complement activation in human blood. Activation of the alternative pathway of complement in blood is under genetic control and increases with age. The genetic variation associated with increased activation of complement in human blood also increased the risk of AMD. Our data are consistent with a disease model in which genetic variation in the complement system increases the risk of AMD by a combination of systemic complement activation and abnormal regulation of complement activation in local tissues.

Purpose: To develop an assay for determining the number of copies of the genes encoding complement factor H related 3 (CFHR3) and 1 (CFHR1) and determine the contribution of copy number variation (CNV) at CFHR3 and CFHR1 to the development of age-related macular degeneration (AMD)., Methods: A multiplex ligation-dependent probe amplification (MLPA) assay was developed to quantify the number of copies of CFHR3 and CFHR1 in humans. Subjects with (n = 252) and without (n = 249) AMD were genotyped using the assay, and the impact on AMD risk was evaluated., Results: The MLPA assay provided a consistent estimate of the number of copies of CFHR3 and CFHR1 in 500 of the 501 samples. Four different combinations of CNVs were observed with frequencies as follows: both CFHR3 and CFHR1 deletion (14%), CFHR3-only deletion (0.4%), CFHR1-only deletion (1.1%), and CFHR1 duplication (0.1%). Deletion of both copies of CFHR3 and CFHR1 decreased the odds of having AMD eightfold (95% CI 2-36) and always occurred on a protective haplotype, never on the risk haplotype tagged by the Y402H risk allele in CFH. The protection conferred by deletion of CFHR3 and CFHR1 could not be distinguished from the absence of the risk haplotype., Conclusions: Both deletions and duplications of genes in the regulation of complement activation locus segregated in Caucasians. Deletion of CFHR3 and CFHR1 protected against the development of AMD at least in part because the deletion tagged a protective haplotype and did not occur on the risk haplotype.

Purpose: To report the outcomes and complications of bilateral simultaneous intravitreal injections performed in the office., Design: Retrospective case series., Methods: Records of 35 patients receiving simultaneous bilateral intravitreal injections between November 2007 and November 2008 were reviewed. Data collected included indication for injection, preinjection and postinjection intraocular pressure (IOP), preinjection and postinjection visual acuity (VA), and complications/complaints after each injection., Results: A total of 208 injections were administered to 35 patients, with a mean of 5.9 injections per patient (range, 2 to 14; standard deviation [SD], 3.68). One hundred and thirty-three eyes received bevacizumab (Avastin; Genentech Inc, South San Francisco, California, USA) alone, 14 received bevacizumab plus preservative-free intravitreal triamcinolone or Triescence (Kenalog; Bristol-Myers Squibb Co, New York, New York, USA), 56 received ranibizumab (Lucentis; Genentech Inc), and 5 received bevacizumab plus dexamethasone (Decadron; Merck, Whitehouse Station, New Jersey, USA). Mean time of postinjection follow-up was 39 days. Postinjection VA follow-up measurements were available for 194 injections. The indication for initiating therapy was choroidal neovascularization from age-related macular degeneration (49 eyes), diabetic macular edema (ME) (13 eyes), proliferative diabetic retinopathy (4 eyes), ME attributable to retinal vein occlusion (2 eyes), and ME attributable to autoimmune retinopathy (2 eyes). The mean VA before each injection was 20/96 and at the next follow-up was 20/91 (P = .40). One patient had a painless, culture-negative endophthalmitis in 1 eye 3 days after bilateral bevacizumab; at 1 year VA improved from 20/400 to 20/80., Conclusions: Simultaneous bilateral intravitreal injections in the office are well tolerated. A separate povidone-iodine preparation, speculum, needle, and syringe were used for each eye. None of the patients requested alternating unilateral injections, after receiving bilateral injections. Patients should be counseled as to the risk of complications.

Purpose: Nonsynonymous coding single nucleotide polymorphisms (nsSNPs) in complement component 3 (C3) alter the risk of age-related macular degeneration (AMD). This was a study of the effect of haplotypes across C3 on AMD risk., Methods: Nine SNPs tagging haplotypes across C3 were genotyped on 738 subjects at the Mayo Clinic. Haplotype analyses were performed with and without conditioning on individual SNPs. Replication studies were performed using 1541 subjects from the age-related eye disease study (AREDS)., Results: Two nsSNPs located 5125 bp apart in the 5' end of C3 showed the highest association (rs1047286 or P314L, P = 9.2E-05; rs2230199 or R102G, P = 4.1E-05) with AMD. The minor alleles of both SNPs tagged a single risk haplotype. The effects of the two nsSNPs could not be distinguished due to high linkage disequilibrium. The risk SNPs preferentially promoted the development of advanced AMD relative to early AMD in both the Mayo and AREDS subjects. Haplotypes in the 3' end of the C3 locus were associated with AMD in both the Mayo and AREDS subjects. The effect persisted after conditioning on the nsSNPs only in the Mayo subjects. No interaction was found between rs2230199 and smoking or other AMD loci., Conclusions: nsSNPs in C3 increased the risk of developing AMD 1.8-fold for 1 risk allele or 2.4-fold for two risk alleles and were preferentially associated with advanced AMD. Further study is needed to determine whether haplotypes in the 3' end of C3 have an independent association with AMD.

Purpose: To report a case of noninfectious endophthalmitis occurring after intravitreal Triesence (preservative-free triamcinolone acetonide) injection., Method: Case report., Results: A 62-year-old patient with macular edema occurring after cataract surgery received 0.1 mL (4 mg) of intravitreal Triesence to the left eye. His vision was 20/60. One day later, he presented with a decrease in vision to light perception upon awakening. He denied ocular pain, and the eye was not red. Clinical examination was remarkable for orbital proptosis, minimal fibrin on the anterior chamber intraocular lens, and a white hypopyon. There was no view of the retina due to vitreous opacities. A vitreous tap and injection of intravitreal Ceftazidime and Vancomycin were performed. Microbiology showed no organisms on gram stain, and the cultures were negative. The endophthalmitis resolved, and the patient recovered vision to 20/70., Conclusions: Noninfectious endophthalmitis can occur after preservative-free commercially available intravitreal Triesence. This case suggests that noninfectious endophthalmitis can occur in the absence of the benzyl alcohol found in preserved preparations of Kenalog.

Purpose: To evaluate the rate of infectious endophthalmitis associated with intravitreal injection of bevacizumab, ranibizumab, and pegaptanib sodium., Methods: A retrospective review of patients who received intravitreal injections of bevacizumab, ranibizumab, and pegaptanib sodium was undertaken. Cases of clinical diagnoses of endophthalmitis or suspected endophthalmitis resulting from intravitreal injection were identified and reviewed. From these data, the risk per injection was estimated., Results: Three patients developed endophthalmitis after the intravitreal injection. The risk per injection was 0.00077 (0.077%). The rate of endophthalmitis was 1 per 1,291 injections., Conclusion: A similar risk of endophthalmitis per injection compared with some trials was obtained in this study. Although no definite risk factors could be identified, intravitreal injections performed by nonretina specialist physicians may be a risk factor for the development of endophthalmitis.

Purpose: To report the results of same-day triple therapy with reduced fluence photodynamic therapy, intravitreal dexamethasone, and bevacizumab in patients with neovascular age-related macular degeneration., Methods: Retrospective case series. Records of patients who received same-day triple therapy with reduced fluence photodynamic therapy (25 J/cm), intravitreal dexamethasone (200 microg), and intravitreal bevacizumab (1.25 mg) were reviewed. All patients had neovascular subfoveal age-related macular degeneration with at least 1 year of follow-up. Snellen visual acuity (VA), central macular thickness on optical coherence tomography, intraocular pressure, and endophthalmitis occurrence were recorded., Results: The 31 patients were observed for a mean of 13.7 months. In all patients, mean baseline VA was 20/80 and vision at final follow-up was 20/60 (P = 0.69). In patients who received previous treatment for exudative age-related macular degeneration (n = 18), mean baseline VA was 20/100 and vision at final follow-up (mean, 13.7 months) was 20/100 (P = 0.31). In treatment-naïve patients (n = 13), mean baseline VA was 20/60 and vision at final follow-up (mean, 13.5 months) was 20/40 (P = 0.31). In all patients, mean central macular thickness was 293 mum at baseline and 245 mum at final follow-up (P = 0.053). In previously treated patients (n = 18), mean central macular thickness was 325 mum at baseline and 265 mum at final follow-up (P = 0.10). In treatment-naïve patients, mean central macular thickness was 249 mum at baseline (n = 13) and 218 mum at final follow-up (P = 0.34). Previously treated patients required more antivascular endothelial growth factor injections (mean = 3.6) than treatment-naïve patients (mean = 0.8), but the mean number of repeat triple therapy treatments was 0.3 in both groups. Changes in intraocular pressure and endophthalmitis were not observed during follow-up., Conclusion: Same-day triple therapy maintained VA and decreased macular thickness in patients with and without previous antivascular endothelial growth factor therapy. Triple therapy may reduce the number of antivascular endothelial growth factor injections in some patients and stabilize vision in some patients not responding to antivascular endothelial growth factor therapy.

Purpose: Common genetic variation in the complement component 1 inhibitor gene (SERPING1) was recently reported to increase the risk of developing age-related macular degeneration (AMD). This study was performed to replicate the association between SERPING1 and AMD., Methods: Seven single nucleotide polymorphisms (SNPs) tagging common haplotypes across SERPING1 were genotyped on 786 (The Mayo Clinic) subjects and the association with AMD studied using single SNP and haplotype association analyses. The SNP in intron 6 (rs2511989) previously reported to increase the risk of AMD was studied in an additional 1,541 subjects from the Age-Related Eye Disease Study (AREDS). Association with specific subtypes of AMD and interaction with four other loci: complement factor H (CFH), age-related maculopathy susceptibility 2 (ARMS2/LOC387715), High Temperature Requirement Factor A1 (HTRA1), complement factor B/complement component 2 (CFB/C2), and complement component 3 (C3) involved in AMD was explored., Results: The seven tag-SNPs were not associated with AMD in the Mayo subjects (p=0.13-0.70) and rs2511989 was also not associated with AMD in the Mayo or AREDS subjects (p=0.44-0.45). Evaluation of haplotypes across SERPING1 did not reveal association with AMD (p=0.14-0.97). SNPs were not associated with AMD subtypes (early, geographic atrophy, or exudation). No interaction with other AMD risk variants was observed., Conclusions: We were unable to replicate the reported association between SERPING1 and AMD in two independent groups of subjects.

The inherited vitreoretinal degenerations or vitreoretinopathies are characterized by congenital and acquired disorders of the eye including early onset cataract, anomalies of the vitreous manifesting as optically empty vitreous, course fibrils, and membranes, and retinal detachment. These diseases include Stickler syndrome types I (STL1) and II (STL2), usually caused by mutations in COL2A1 and COL11A1 respectively. Wagner syndrome (WGN1) is associated with mutations in versican (CSPG2) and snowflake vitreoretinal degeneration (SVD) with a mutation in a potassium channel (KCNJ13). The cataract is often cortical and may be wedge-shaped, but does not distinguish between the different syndromes. The congenital vitreous defect is usually characterized as fibrillar degeneration (STL2, WGN1, and SVD) or as a vestigial membrane just behind the lens (STL1). Peripheral chorioretinal atrophy with nyctalopia is prominent in WGN1. Intraretinal crystals may be visible in the periphery using a contact lens in SVD and corneal guttae, a flat appearance to the optic nerve head and mild atrophy of the peripheral retinal pigment epithelium are also common features. Other vitreoretinal degenerations including a number of chondrodysplasias in addition to STL1 and STL2, enhanced S-cone syndrome caused by mutations in NR2E3, and autosomal dominant vitreoretinochoroidopathy caused by mutations in VMD2 are discussed. Patients with unexplained early onset cataract or retinal detachment should be carefully evaluated for vitreoretinal degeneration. Theses diseases share overlapping clinical features with common complex traits affecting the eye (myopia, corneal endothelial dystrophy, lattice degeneration), and may provide insight into the mechanisms of common eye diseases.

Intralesional injection of corticosteroid suspensions into or adjacent to the ocular adnexa is performed by a number of medical specialists including dermatologists. Although not widely known outside of the ophthalmic community, these injections can lead to blindness through embolization of the central retinal artery. A case of blindness following injection into the forehead lesion of a child with the rare dermatologic condition pyogenic arthritis and pyodermic gangrenosum syndrome is reported. Injection into or near the ocular adnexa may be performed in small boluses to reduce the chance of retinal embolization following entry into the arterial system.

Background: To describe the occurrence of ocular hypertension in four patients following injection of ranibizumab intravitreally., Methods: Case series., Results: Four patients had high intraocular pressure after intravitreal ranibizumab 0.5 mg. Ocular hypertension occurred 1 month after the second ranibizumab injection in patients 1 and 3, and 1 month after the first ranibizumab in patient 2. In patient 4, it occurred several hours after the first ranibizumab injection. In all patients, the IOP increase was sustained across several visits, requiring control with topical glaucoma therapy, and in two cases the addition of a systemic carbonic anhydrase inhibitor. None of the patients had a previous history of glaucoma, ocular hypertension or IOP asymmetry and the IOP was as high as 30, 34, 46, and 50 mmHg in the four patients., Conclusion: Severe and sustained ocular hypertension may occur after intravitreal ranibizumab. Although the mechanism of the pressure rise is unknown, all eyes in our series were controlled with medical therapy.

Genetic association studies are identifying genetic risks for common complex ocular traits such as age-related macular degeneration (AMD). The subjects used for discovery of these loci have been largely from clinic-based, case-control studies. Typically, only the primary phenotype (e.g., AMD) being studied is systematically documented and other complex traits (e.g., affecting the eye) are largely ignored. The purpose of this study was to characterize these other or secondary complex ocular traits present in the cases and controls of clinic-based studies being used for genetic study of AMD. The records of 100 consecutive new patients (of any diagnosis) age 60 or older for which all traits affecting the eye had been recorded systematically were reviewed. The average patient had 3.5 distinct diagnoses. A subset of 10 complex traits was selected for further study because they were common and could be reliably diagnosed. The density of these 10 complex ocular traits increased by 0.017 log-traits/year (P = 0.03), ranging from a predicted 2.74 at age 60 to 4.45 at age 90. Trait-trait association was observed only between AMD and primary vitreomacular traction (P = 0.0009). Only 1% of subjects age 60 or older had no common complex traits affecting the eye. Extrapolations suggested that a study of 2000 similar subjects would have sufficient power to detect genetic association with an odds ratio of 2.0 or less for 4 of these 10 traits. In conclusion, the high prevalence of complex traits affecting the aging eye and the inherent biases in referral patterns leads to the potential for confounding by undocumented secondary traits within case-control studies. In addition to the primary trait, other common ocular phenotypes should be systematically documented in genetic association studies so that adjustments for potential trait-trait associations and other bias can be made and genetic risk variants identified in secondary analyses.

Background: Injection of drugs into the vitreous can lead to intraocular inflammation through infectious and non-infectious processes. Failure to recognize an eye with anterior chamber and vitreous cell as sterile inflammation can lead to unnecessary treatment for endophthalmitis., Methods: Four cases of uveitis following intravitreal bevacizumab (Avastin) for exudative age-related macular degeneration are described followed by review of the literature., Results: Four patients presented with uveitis. Two patients presented with pain and red eye associated with iritis and two patients with vitritis, several days following intravitreal injection of bevacizumab. No paracentesis was performed and no corneal epithelial defect was created. Both patients with iritis were presumed to have sterile intraocular inflammation since the anterior chamber cell was much greater than the vitreous cell and resolved with cycloplegic and topical corticosteroid therapy. The third patient presented only with vitreous cell which resolved without therapy. The fourth patient had anterior chamber cell and vitreous cell with clumps, which resolved with topical prednisolone acetate. The inflammation resolved in all cases within 1 to 2 weeks., Conclusion: There are few published cases of uveitis following bevacizumab. With its rising use, it is important to be aware of its potential to be associated with intraocular inflammation.

Purpose: Evidence from genetic-association studies in conjunction with the demonstration of complement deposition in the retina and choroid implicates noncellular pathways of innate immunity in the pathogenesis of age-related macular degeneration (AMD). The purpose of this study was to determine whether common variation in the 10 human toll-like receptors (TLRs) alters the risk of AMD., Methods: Sixty-eight SNPs were iteratively genotyped across the TLR genes in a cohort of 577 subjects, with and without AMD. Two additional cohorts were used for replication studies. Standard genetic-association methods were used to analyze the results for association with disease and interaction with other loci., Results: Coding SNPs in TLR3 (rs3775291) and TLR7 (rs179008) showed association with AMD in one group (P = 0.01 and P = 0.02, respectively) before correction for multiple testing. For both SNPs, the association with AMD arose due to an excess of heterozygotes compared with homozygotes for the major allele. The two coding SNPs were not associated with AMD in another case-control cohort or an extended-family cohort. Although an intronic SNP in TLR4 was associated marginally with AMD (P = 0.03), it was not possible to replicate a previous association with the rare coding SNP D299G in this gene (P = 0.6)., Conclusions: Although borderline support for association between polymorphisms in TLR genes and AMD was reported for some cohorts, these initial observations of coding SNPs in TLR3, TLR4, and TLR7 were not replicated. TLR variants are unlikely to have a major impact on overall AMD risk, and the common variants studied were not associated with AMD.

Snowflake vitreoretinal degeneration (SVD, MIM 193230) is a developmental and progressive hereditary eye disorder that affects multiple tissues within the eye. Diagnostic features of SVD include fibrillar degeneration of the vitreous humor, early-onset cataract, minute crystalline deposits in the neurosensory retina, and retinal detachment. A genome-wide scan previously localized the genetic locus for SVD to a 20 Mb region flanked by D2S2158 and D2S2202. This region contains 59 genes, of which 20 were sequenced, disclosing a heterozygous mutation (484C > T, R162W) in KCNJ13, member 13 of subfamily J of the potassium inwardly rectifying channel family in all affected individuals. The mutation in KCNJ13, the gene encoding Kir7.1, was not present in unaffected family members and 210 control individuals. Kir7.1 localized to human retina and retinal pigment epithelium and was especially prevalent in the internal limiting membrane adjacent to the vitreous body. Molecular modeling of this mutation predicted disruption of the structure of the potassium channel in the closed state located immediately adjacent to the cell-membrane inner boundary. Functionally, unlike wild-type Kir7.1 whose overexpression in CHO-K1 cells line produces highly selective potassium current, overexpression of R162W mutant Kir7.1 produces a nonselective cation current that depolarizes transfected cells and increases their fragility. These results indicate that the KCNJ13 R162W mutation can cause SVD and further show that vitreoretinal degeneration can arise through mutations in genes whose products are not structural components of the vitreous.

Genome-wide association studies (GWASs) assess correlation between traits and DNA sequence variation using large numbers of genetic variants such as single nucleotide polymorphisms (SNPs) distributed across the genome. A GWAS produces many trait-SNP associations with low p-values, but few are replicated in subsequent studies. We sought to determine if characteristics of the genomic loci associated with a trait could be used to identify initial associations with a higher chance of replication in a second cohort. Data from the age-related eye disease study (AREDS) of 100,000 SNPs on 395 subjects with and 198 without age-related macular degeneration (AMD) were employed. Loci highly associated with AMD were characterized based on the distribution of genotypes, level of significance, and clustering of adjacent SNPs also associated with AMD suggesting linkage disequilibrium or multiple effects. Forty nine loci were highly associated with AMD, including 3 loci (CFH, C2/BF, LOC387715/HTRA1) already known to contain important genetic risks for AMD. One additional locus (C3) reported during the course of this study was identified and replicated in an additional study group. Tag-SNPs and haplotypes for each locus were evaluated for association with AMD in additional cohorts to account for population differences between discovery and replication subjects, but no additional clearly significant associations were identified. Relying on a significant genotype tests using a log-additive model would have excluded 57% of the non-replicated and none of the replicated loci, while use of other SNP features and clustering might have missed true associations.

LOC387715 is a hypothetical gene located on human chromosome 10q26.13 that is associated with the development of age-related macular degeneration (AMD). The native open reading frame (ORF) of LOC387715 cDNA - LOC387715(ORF), contains a large number of Escherichia coli (E. coli) rare codons (RC) including 5.6% and 15.0% Group-I and IIa translational problem causative (TPC) RCs, respectively, which forms 3 and 4 simple E. coli rare codon clusters (RCC) where RCs are spaced by 1 and 2 respective non-TPC codons and one complex E. coli RCC where RCs and RCCs are spaced by <5 non-TPC codons. We modified the entire 35 E. coli RCs (6, 16 and 13 Group I, IIa and IIb RCs, respectively) present in LOC387715(ORF) with their optimal or sub-optimal synonymous degenerate codons, and the resulted LOC387715(ORF)m was free from Shine-Dalgarno-like sequence (SDLS) and ribosome binding site complementary sequence (RBSCS). SDS-PAGE and Western blotting analysis demonstrated that LOC387715(ORF)m was capable of highly expressing the recombinant protein rLOC387715 in E. coli. Mass spectrometry analysis indicated that the bacterial expressed rLOC387715 contained the correct and expected amino acid (aa) sequence without aa misincorporation, aa missing or frame-shift. The results suggest that high and authentic expression of LOC387715 recombinant protein in E. coli was achieved by the synonymous modification of its native ORF cDNA sequence for all the 3 groups of bacterial RCs and the simultaneous elimination of SDLS and RBSCS sequences.

Purpose: To use the power of knowledge acquisition and machine learning in the development of a collaborative computer classification system based on the features of age-related macular degeneration (AMD)., Methods: A vocabulary was acquired from four AMD experts who examined 100 ophthalmoscopic images. The vocabulary was analyzed, hierarchically structured, and incorporated into a collaborative computer classification system called IDOCS. Using this system, three of the experts examined images from a second set of digital images compiled from more than 1000 patients with AMD. Images were annotated, and features were identified and defined. Decision trees, a machine learning method, were trained on the data collected and used to extract patterns. Interrelationships between the data from the different clinicians were investigated., Results: Six drusen classes in the structured vocabulary were largely sufficient to describe all the identified features. The decision trees classified the data with 76.86% to 88.5% accuracy and distilled patterns in the form of hierarchical trees composed of 5 to 15 nodes. Experts were largely consistent in their characterization of soft, and to a lesser extent, hard drusen, but diverge in definition of other drusen. Size and crystalline morphology were the main determinants of drusen type across all experts., Conclusions: Machine learning is a powerful tool for the characterization of disease phenotypes. The creation of a defined feature set for AMD will facilitate the development of an IDOCS-based classification system.

Purpose: Autosomal dominant Stargardt disease-3 (STGD3) is caused by mutations in elongase of very long chain fatty acids-4 (ELOVL4). The goal of this study was to generate and characterize heterozygous and homozygous knockin-mice that carry a human STGD3 pathogenic mutation in the mouse Elovl4 gene., Methods: Recombinant Stgd3-knockin mice were generated using a DNA construct which introduced a pathogenic five-base pair deletion and two point mutations in exon 6 of the Elovl4 gene. Stgd3-mouse genotypes were confirmed by Southern blot analysis and expression of wild-type (wt) and mutated Elovl4 mRNAs assayed by nuclease protection assay. The retinal phenotype of heterozygous Stgd3 mice was characterized by morphological studies, elecroretinographic (ERG) analysis and assay of lipofuscin accumulation. Homozygous Stgd3 mice were examined for both retinal and gross morphology. They were also analyzed for skin morphology and skin barrier function, and for epidermal lipid content using high performance liquid chromatography (HPLC) combined with mass spectrometry (MS)., Results: The Stgd3 allele codes for a truncated mouse Elovl4 protein, which also contains the same aberrant 8-amino acid C-terminus encoded by the human pathogenic STGD3 allele. Heterozygous Stgd3 mice expressed equal amounts of both wt and mutant Elovl4 mRNAs in the retina, showed no significant changes in retinal morphology, but did show accumulation of lipofuscin and reduced visual function. Homozygous Stgd3 mice were born with an expected Mendelian frequency, without any initial gross anatomical or behavioral abnormalities. By 6-12 h postpartum, they became dehydrated and died. A skin permeability assay detected a defect in epidermal barrier function. Homozygous mutant epidermis expressed a normal content of mutated Elovl4 mRNA and contained all four epidermal cellular layers. HPLC/MS analysis of epidermal lipids revealed the presence of all barrier lipids with the exception of the complete absence of acylceramides, the critical lipids for barrier function of the skin., Conclusions: The generated Stgd3-knockin mice are a genetic model of human STGD3 and reproduce features of the human disease: accumulation of lipofuscin and reduced visual functions. Homozygous Stgd3 mice showed a complete absence of acylceramides from the epidermis. Their absence suggests a role for Elovl4 in acylceramide synthesis, and in particular, a role in the synthesis of the unique very long chain C30-C40 fatty acids present in skin acylceramides.

During the past few years systematic investigation into the epidemiology, genetics, and pathophysiology of age-related macular degeneration (AMD) has provided important new insight into this leading cause of vision loss in older persons. These studies provide a view of AMD as a complex trait influenced by well-established genetic and environmental risks that leads to the deposition of inflammatory deposits in the outer retina. This maculopathy leads to visual dysfunction through a variety of mechanisms and complications that can be observed in both humans and animal models. In this review, the risks associated with AMD in humans and the animal models used to study AMD and its complications will be summarized. No effort has been made to perform a comprehensive citation of all areas of AMD genetics and animal models, but rather a selection of observations and supporting references illustrative of the current state of the field is presented.

Purpose: Adult-onset vitelliform macular dystrophy (AVMD) is a pleomorphic late-onset macular phenotype characterized by a central yellow deposit between the neural retina and retinal pigment epithelium. Mutations in the genes encoding peripherin/RDS and VMD2 have been previously reported in some subjects with AVMD. The purpose of this investigation was to determine the prevalence of mutations in these two genes in a cohort of cases with macular dystrophies presenting with vitelliform lesions in adulthood., Methods: Fifty nine consecutively ascertained and unrelated subjects prospectively coded as pattern or vitelliform macular dystrophies were reviewed and twelve subjects with a vitelliform lesion were identified. Patient evaluation included comprehensive ocular examination, retinal imaging, and functional studies in selected subjects. The RDS and VMD2 genes were screened for variation by direct DNA sequencing of coding regions and intron/exon boundaries., Results: Twenty-two DNA sequence variants were identified in the genes encoding RDS and VMD2. A Pro210Arg variant found in the RDS gene of one subject was the only definite mutation detected in either gene., Conclusions: The Pro210Arg mutation has been reported previously in patients with pattern dystrophy confirming the observation that pattern dystrophy can present with an AVMD phenotype. Although RDS and VMD2 are the only known genes with mutations contributing to AVMD, our series demonstrates that most patients have mutations in genes that have yet to be discovered.

Purpose: To describe the clinical features of and identify the mutation responsible for an autosomal dominant pattern dystrophy occurring in a three-generation family., Methods: Five affected family members underwent clinical examination and additional testing including intravenous fluorescein angiography where indicated. Mutation screening of the peripherin/RDS gene was performed., Results: Visual acuity ranged from 20/20 to counting fingers. All patients who reported vision loss noted the onset after the age of 40 years. Predominantly perifoveal, discrete, retinal pigment epithelial changes were present in all patients. Two patients had extensive peripheral yellowish flecks, and one had an atrophic macular scar. Mutation screening of the complete peripherin/RDS coding sequence and exon/intron boundaries revealed a novel splice site mutation., Conclusion: A three-generation family with an autosomal dominant pattern dystrophy arising from a previously unreported splice site mutation in the RDS gene is described.