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Purpose: To investigate the distribution of genotypes and natural history of ABCA4-associated retinal disease in a large cohort of patients seen at a single institution., Design: Retrospective, single-institution cohort review., Participants: Patients seen at the University of Iowa between November 1986 and August 2022 clinically suspected to have disease caused by sequence variations in ABCA4., Methods: DNA samples from participants were subjected to a tiered testing strategy progressing from allele-specific screening to whole genome sequencing. Charts were reviewed, and clinical data were tabulated. The pathogenic severity of the most common alleles was estimated by studying groups of patients who shared 1 allele. Groups of patients with shared genotypes were reviewed for evidence of modifying factor effects., Main Outcome Measures: Age at first uncorrectable vision loss, best-corrected visual acuity, and the area of the I2e isopter of the Goldmann visual field., Results: A total of 460 patients from 390 families demonstrated convincing clinical features of ABCA4-associated retinal disease. Complete genotypes were identified in 399 patients, and partial genotypes were identified in 61. The median age at first vision loss was 16 years (range, 4-76 years). Two hundred sixty-five families (68%) harbored a unique genotype, and no more than 10 patients shared any single genotype. Review of the patients with shared genotypes revealed evidence of modifying factors that in several cases resulted in a > 15-year difference in age at first vision loss. Two hundred forty-one different alleles were identified among the members of this cohort, and 161 of these (67%) were found in only a single individual., Conclusions: ABCA4-associated retinal disease ranges from a very severe photoreceptor disease with an onset before 5 years of age to a late-onset retinal pigment epithelium-based condition resembling pattern dystrophy. Modifying factors frequently impact the ABCA4 disease phenotype to a degree that is similar in magnitude to the detectable ABCA4 alleles themselves. It is likely that most patients in any cohort will harbor a unique genotype. The latter observations taken together suggest that patients' clinical findings in most cases will be more useful for predicting their clinical course than their genotype., Financial Disclosure(s): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article., (Copyright © 2024 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Background: People with cognitive disabilities such as intellectual and developmental disabilities face significant barriers to accessing high-quality health care services. Barriers may be exacerbated for those with co-occurring mental health conditions., Objective: This study compares patient experiences of health care services between adults with and without cognitive disabilities and, among people with a cognitive disability, those with and without co-occurring mental health conditions., Methods: Cross-sectional analyses were conducted using 2021 Medical Expenditure Panel Survey data, a national U.S. survey, to examine differences in Consumer Assessment of Healthcare Providers and Systems measures., Results: Adults with cognitive disabilities reported lower satisfaction with health care services compared to the general population (7.62 (95% confidence interval (CI): 7.41-7.83) vs. 8.33 (95% CI: 8.29-8.38) on scale from 0 to 10). Adults with cognitive disabilities were less likely to report that providers listened carefully to them (odds ratio (OR): 0.55, 95% CI: 0.42-0.71), explained things in a way that was easy to understand (OR: 0.48, 95% CI: 0.35-0.66), showed respect for what they had to say (OR: 0.38, 95% CI: 0.29-0.51), spent enough time with them (OR: 0.52, 95% CI: 0.40-0.69), or gave advice that was easy to understand (OR: 0.40, 95% CI: 0.28-0.58) compared to the general population. Among adults with cognitive disabilities, there were no differences based on co-occurring mental health conditions., Conclusions: Adults with cognitive disabilities report lower satisfaction with health care services driven by worse experiences with the health care system. Policies to increase provider capacity to support this population should be prioritized., Competing Interests: Declaration of competing interest Authors have no conflicts of interest to report., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Some human retinal diseases are characterized by pathology that is restricted to specific cell types and to specific regions of the eye. Several disease entities either selectively affect or spare the macula, the retina region at the center of the posterior pole. Photoreceptor cells in the macula are involved in high-acuity vision and require metabolic support from non-neuronal cell types. Some macular diseases involve the retinal pigment epithelium (RPE), an epithelial cell layer with several metabolic-support functions essential for the overlying photoreceptors. In the current study, the ways in which RPE confers region-specific disease susceptibility were determined by examining heterogeneity within RPE tissue from human donors. RPE nuclei from the macular and peripheral retina were profiled using joint single-nucleus RNA and ATAC sequencing. The expression of several genes differed between macular and peripheral RPE. Region-specific ATAC peaks were found, suggesting regulatory elements used exclusively by macular or peripheral RPE. Across anatomic regions, subpopulations of RPE were identified that appeared to have differential levels of expression of visual cycle genes. Finally, loci associated with age-related macular degeneration were examined for a better understanding of RPE-specific disease phenotypes. These findings showed variations in the regulation of gene expression in the human RPE by region and subpopulation, and provide a source for a better understanding of the molecular basis of macular disease., (Copyright © 2023 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

Introduction: In response to the role of opioid prescribing in the U.S. opioid crisis, states have enacted laws intended to curb high risk opioid prescribing practices. This study assessed the effects of state prescribing cap laws that limit the dose and/or duration of dispensed opioid prescriptions on opioid prescribing patterns and opioid overdose., Methods: We identified 1,414,908 adults from a large U.S. administrative insurance claims database. Treatment states included 32 states that implemented a prescribing cap law between 2017 and 2019. Comparison states included 16 states and DC without a prescribing cap law by 2019. A difference-in-differences approach with staggered policy adoption was used to assess effects of these laws on opioid analgesic prescribing and opioid overdose., Results: State opioid prescribing cap laws were not associated with changes in the proportion of people receiving opioid analgesic prescriptions, the dose or duration of opioid prescriptions, or opioid overdose. States with laws that imposed days' supply limits only versus days' supply and dosage limits, as well as with specific law provisions also showed no association with opioid prescribing or opioid overdose outcomes., Conclusions: State opioid prescribing cap laws did not appear to impact outcomes related to opioid analgesic prescribing or opioid overdose. These findings are potentially due to the limited scope of these laws, which often apply only to a subset of opioid prescriptions and include professional judgment exemptions., Competing Interests: Conflict of Interest Drs. Tormohlen, McCourt, Schmid, Stone, Stuart, Davis, and McGinty have no financial disclosures. Dr. Bicket reports past service as a consultant for Axial Healthcare and Alosa Health, both unrelated to the submitted work., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Objectives: To characterize primary care physicians' (PCPs) attitudes and beliefs about people with opioid use disorder (OUD) and to understand the association between PCPs' stigmatizing attitudes and their OUD treatment practices, beliefs about treatment effectiveness, and support for policies designed to improve access to OUD medications., Methods: We conducted a national postal survey of U.S. PCPs from January to August 2019. Survey items measured respondents' attitudes, beliefs, and current treatment practices. Data were analyzed using descriptive statistics and logistic regression., Results: Of the original 1000 PCPs in the survey sample, 668 were deemed eligible to participate in the study. The survey was completed by 361 PCPs for an adjusted response rate of 54 %. PCPs reported high levels of stigmatizing attitudes. Less than 30 % of PCPs reported that they were willing to have a person taking medication for OUD as a neighbor or marry into their family, even if that person was being treated with medication. Greater stigma was associated with an 11 percentage point lower likelihood that PCPs prescribed OUD medication and lower support for policies intended to increase access to OUD medication., Conclusions: Addressing OUD stigma among PCPs is a public health priority in addressing the ongoing opioid crisis., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Background: In response to the role overprescribing has played in the U.S. opioid crisis, in the past decade states have enacted four main types of laws to curb opioid prescribing: mandatory prescription drug monitoring program (PDMP) enrollment laws requiring clinicians to register with a PDMP; mandatory PDMP query laws requiring clinicians to check a PDMP prior to prescribing opioids; pill mill laws regulating pain management clinics; and opioid prescribing cap laws limiting the dose/duration of opioid prescriptions. While 47 states now have one or more of these laws in place, little is known about implementation and enforcement strategies, facilitators, and barriers., Methods: From November 2017 to February 2019, we interviewed 114 professionals involved in state opioid prescribing law implementation and enforcement in 20 states and identified common themes., Results: Implementation efforts focused on awareness campaigns and targeted training of key front-line implementers. Enforcement strategies included active, complaint-based, and automated strategies. Collaboration across agencies and stakeholders, particularly health agencies and law enforcement, was identified as an important facilitator of implementation and enforcement. Two key interrelated barriers were identified: the complexity of state opioid prescribing laws in terms of which providers, patients, and prescriptions they applied to, and IT infrastructure., Conclusion: Despite differing approaches, our findings suggest similar barriers to implementation and enforcement across state opioid prescribing laws. Strategies are needed to ease implementation and enforcement of laws that apply only to specific sub-sets of providers, patients, or prescriptions and address issues of access and data utilization of the PDMP., Competing Interests: Declaration of Competing Interests Dr. Bicket reports Axial Healthcare (past served on an advisory board, stock options) and Alosa Health (advisory board). These arrangements have been reviewed and approved by Johns Hopkins University in accordance with its conflict of interest policies. Dr. Alexander previously served as Chair of FDA’s Peripheral and Central Nervous System Advisory Committee; has served as a paid advisor to IQVIA; and is a consultant and holds equity in Monument Analytics, a health care consultancy whose clients include the life sciences industry as well as plaintiffs in opioid litigation; and is a member of OptumRx’s National P&T Committee. This arrangement has been reviewed and approved by Johns Hopkins University in accordance with its conflict of interest policies. The other co-authors have no conflicts of interest to disclose., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Cell replacement therapies are often enhanced by utilizing polymer scaffolds to improve retention or direct cell orientation and migration. Obstacles to refinement of such polymer scaffolds often include challenges in controlling the microstructure of biocompatible molecules in three dimensions at cellular scales. Two-photon polymerization of acrylated poly(caprolactone) (PCL) could offer a means of achieving precise microstructural control of a material in a biocompatible platform. In this work, we studied the effect of various formulation and two-photon polymerization parameters on minimum laser power needed to achieve polymerization, resolution, and fidelity to a target 3D model designed to be used for retinal cell replacement. Overall, we found that increasing the concentration of crosslink-able groups decreased polymerization threshold and the size of resolvable features while increasing fidelity of the scaffold to the 3D model. In general, this improvement was achieved by increasing the number of acrylate groups per prepolymer molecule, increasing the acrylated PCL concentration, or decreasing its molecular weight. Resulting two-photon polymerized PCL scaffolds successfully supported human iPSC derived retinal progenitor cells in vitro. Sub-retinal implantation of cell free scaffolds in a porcine model of retinitis pigmentosa did not cause inflammation, infection or local or systemic toxicity after one month. In addition, comprehensive ISO 10993 testing of photopolymerized scaffolds revealed a favorable biocompatibility profile. These results represent an important step towards understanding how two-photon polymerization can be applied to a wide range of biologically compatible chemistries for various biomedical applications. STATEMENT OF SIGNIFICANCE: Inherited retinal degenerative blindness results from the death of light sensing photoreceptor cells. To restore high-acuity vision a photoreceptor cell replacement strategy will likely be necessary. Unfortunately, single cell injection typically results in poor cell survival and integration post-transplantation. Polymeric biomaterial cell delivery scaffolds can be used to promote donor cell viability, control cellular polarity and increase packing density. A challenge faced in this endeavor has been developing methods suitable for generating scaffolds that can be used to deliver stem cell derived photoreceptors in an ordered columnar orientation (i.e., similar to that of the native retina). In this study we combined the biomaterial poly(caprolactone) with two-photon lithography to generate a biocompatible, clinically relevant scaffold suitable for retina cell delivery., (Copyright © 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Early age-related macular degeneration (AMD) is characterized by degeneration of the choriocapillaris, the vascular supply of retinal photoreceptor cells. We assessed vascular loss during disease progression in the choriocapillaris and larger vessels in the deeper choroid. Human donor maculae from controls (n = 99), early AMD (n = 35), or clinically diagnosed with geographic atrophy (GA; n = 9, collected from outside the zone of retinal pigment epithelium degeneration) were evaluated using Ulex europaeus agglutinin-I labeling to discriminate between vessels with intact endothelial cells and ghost vessels. Morphometric analyses of choriocapillaris density (cross-sectional area of capillary lumens divided by length) and of vascular lumen/stroma ratio in the outer choroid were performed. Choriocapillaris loss was observed in early AMD (Bonferroni-corrected P = 0.024) with greater loss in GA (Bonferroni-corrected P < 10 -9 ), even in areas of intact retinal pigment epithelium. In contrast, changes in lumen/stroma ratio in the outer choroid were not found to differ between controls and AMD or GA eyes (P > 0.05), suggesting choriocapillaris changes are more prevalent in AMD than those in the outer choroid. In addition, vascular endothelial growth factor-A levels were negatively correlated with choriocapillaris vascular density. These findings support the concept that choroidal vascular degeneration, predominantly in the microvasculature, contributes to dry AMD progression. Addressing capillary loss in AMD remains an important translational target., (Copyright © 2019 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

Purpose: To examine the association between sequence variants in genetic risk factors for age-related macular degeneration (AMD) and delayed rod-mediated dark adaptation (RMDA), the first functional biomarker for incident AMD, in older adults with normal macular health and early AMD., Design: Cross-sectional., Participants: Adults 60 years of age or older showing normal macular health (defined as both eyes at step 1 on the Age-Related Eye Disease Study 9-step AMD classification system) and those with AMD in one or both eyes (defined as steps 2-9)., Methods: Single nucleotide polymorphisms were genotyped in the complement factor H (CFH) and ARMS2 genes using a Taqman assay. Rod-mediated dark adaptation was assessed in 1 eye after photobleach with targets centered at 5° on the inferior vertical meridian. Rate of dark adaptation was defined by rod intercept time (RIT), duration (in minutes) required for sensitivity to reach a criterion sensitivity level in the latter half of the second component of rod recovery. Associations between CFH and ARMS2 polymorphisms and RMDA were adjusted for age and smoking., Main Outcome Measure: Rod intercept time., Results: The sample consisted of 543 participants having both genotype and RIT determination; 408 showed normal macular health and 135 demonstrated AMD, most having early AMD (124 of 135). For the combined sample, higher RIT (slower RMDA) was observed for both the A69S variant in ARMS2 and the Y402H variant in CFH (adjusted P = 0.0001 and P = 0.0023, respectively). For healthy participants, the A69S variant in ARMS2 was associated with higher RIT (adjusted P = 0.0011), whereas the Y402H variant in CFH was not (adjusted P = 0.2175). For AMD patients, the A69S variant of ARMS2 and the Y402H variant of CFH were associated with higher RIT (adjusted P = 0.0182 and P = 0.0222, respectively). Those with a larger number of high-risk ARMS2 and CFH alleles showed higher RIT, in both healthy and AMD groups (adjusted P = 0.0002 and P < 0.0001, respectively)., Conclusions: We report a novel association wherein older adults with high-risk ARMS2 and CFH genotypes are more likely to demonstrate delayed RMDA, the first functional biomarker for incident early AMD. Before the AMD clinical phenotype is present, those showing normal macular health with the ARMS2 A69S allele demonstrate delayed RMDA. Understanding ARMS2 function is a research priority., (Copyright © 2018 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Purpose: To devise a comprehensive multiplatform genetic testing strategy for inherited retinal disease and to describe its performance in 1000 consecutive families seen by a single clinician., Design: Retrospective series., Participants: One thousand consecutive families seen by a single clinician., Methods: The clinical records of all patients seen by a single retina specialist between January 2010 and June 2016 were reviewed, and all patients who met the clinical criteria for a diagnosis of inherited retinal disease were included in the study. Each patient was assigned to 1 of 62 diagnostic categories, and this clinical diagnosis was used to define the scope and order of the molecular investigations that were performed. The number of nucleotides evaluated in a given subject ranged from 2 to nearly 900 000., Main Outcome Measures: Sensitivity and false genotype rate., Results: Disease-causing genotypes were identified in 760 families (76%). These genotypes were distributed across 104 different genes. More than 75% of these 104 genes have coding sequences small enough to be packaged efficiently into an adeno-associated virus. Mutations in ABCA4 were the most common cause of disease in this cohort (173 families), whereas mutations in 80 genes caused disease in 5 or fewer families (i.e., 0.5% or less). Disease-causing genotypes were identified in 576 of the families without next-generation sequencing (NGS). This included 23 families with mutations in the repetitive region of RPGR exon 15 that would have been missed by NGS. Whole-exome sequencing of the remaining 424 families revealed mutations in an additional 182 families, and whole-genome sequencing of 4 of the remaining 242 families revealed 2 additional genotypes that were invisible by the other methods. Performing the testing in a clinically focused tiered fashion would be 6.1% more sensitive and 17.7% less expensive and would have a significantly lower average false genotype rate than using whole-exome sequencing to assess more than 300 genes in all patients (7.1% vs. 128%; P < 0.001)., Conclusions: Genetic testing for inherited retinal disease is now more than 75% sensitive. A clinically directed tiered testing strategy can increase sensitivity and improve statistical significance without increasing cost., (Copyright © 2017 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Endothelial cells (ECs) of the choriocapillaris are one of the first cell types lost during age-related macular degeneration (AMD), and cell replacement therapy is currently a very promising option for patients with advanced AMD. We sought to develop a reliable method for the production of human choroidal extracellular matrix (ECM) scaffolds, which will allow for the study of choroidal EC (CEC) replacement strategies in an environment that closely resembles the native tissue. Human RPE/choroid tissue was treated sequentially with Triton X-100, SDS, and DNase to remove all native cells. While all cells were successfully removed from the tissue, collagen IV, elastin, and laminin remained, with preserved architecture of the acellular vascular tubes. The ECM scaffolds were then co-cultured with exogenous ECs to determine if the tissue can support cell growth and allow EC reintegration into the decellularized choroidal vasculature. Both monkey and human ECs took up residence in the choriocapillary tubes of the decellularized tissue. Together, these data suggest that our decellularization methods are sufficient to remove all cellular material yet gentle enough to preserve tissue structure and allow for the optimization of cell replacement strategies., Statement of Significance: Age-related macular degeneration (AMD) is a devastating disease affecting more than 600 million people worldwide. Endothelial cells of the choriocapillaris (CECs) are among the first cell types lost in early AMD, and cell replacement therapy is currently the most promising option for restoring vision in patients with advanced AMD. In order to study CEC replacement strategies we have generated a 3D choroid scaffold using a novel decellularization method in human RPE/choroid tissue. To our knowledge, this is the first report describing decellularization of human RPE/choroid, as well as recellularization of a choroid scaffold with CECs. This work will aid in our development and optimization of cell replacement strategies using a tissue scaffold that is similar to the in vivo environment., (Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Recent advances in induced pluripotent stem cell (iPSC) technology have paved the way for the production of patient-specific neurons that are ideal for autologous cell replacement for treatment of neurodegenerative diseases. In the case of retinal degeneration and associated photoreceptor cell therapy, polymer scaffolds are critical for cellular survival and integration; however, prior attempts to materialize this concept have been unsuccessful in part due to the materials' inability to guide cell alignment. In this work, we used two-photon polymerization to create 180μm wide non-degradable prototype photoreceptor scaffolds with varying pore sizes, slicing distances, hatching distances and hatching types. Hatching distance and hatching type were significant factors for the error of vertical pore diameter, while slicing distance and hatching type most affected the integrity and geometry of horizontal pores. We optimized printing parameters in terms of structural integrity and printing time in order to create 1mm wide scaffolds for cell loading studies. We fabricated these larger structures directly on a porous membrane with 3µm diameter pores and seeded them with human iPSC-derived retinal progenitor cells. After two days in culture, cells nested in and extended neuronal processes parallel to the vertical pores of the scaffolds, with maximum cell loading occurring in 25μm diameter pores. These results highlight the feasibility of using this technique as part of an autologous stem cell strategy for restoring vision to patients affected with retinal degenerative diseases., Statement of Significance: Cell replacement therapy is an important goal for investigators aiming to restore neural function to those suffering from neurodegenerative disease. Cell delivery scaffolds are frequently necessary for the success of such treatments, but traditional biomaterials often fail to facilitate the neuronal orientation and close packing needed to recapitulate the in vivo environment. Here, we use two-photon polymerization to create prototype cell scaffolds with densely packed vertical pores for photoreceptor cell loading and small, interconnected horizontal pores for nutrient diffusion. This study offers a thorough characterization of how two-photon polymerization parameters affect final structural outcomes and printing time. Our findings demonstrate the feasibility of using two-photon polymerization to create scaffolds that can align neuronal cells in 3D and are large enough to be used for transplantation. In future work, these scaffolds could comprise biodegradable materials with tunable microstructure, elastic modulus and degradation time; a significant step towards a promising treatment option for those suffering from late-stage neurodegeneration, including retinal degenerative blindness., (Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Retinitis pigmentosa (RP) is a heterogeneous group of monogenic disorders characterized by progressive death of the light-sensing photoreceptor cells of the outer neural retina. We recently identified novel hypomorphic mutations in the tRNA Nucleotidyl Transferase, CCA-Adding 1 (TRNT1) gene that cause early-onset RP. To model this disease in vitro, we generated patient-specific iPSCs and iPSC-derived retinal organoids from dermal fibroblasts of patients with molecularly confirmed TRNT1-associated RP. Pluripotency was confirmed using rt-PCR, immunocytochemistry, and a TaqMan Scorecard Assay. Mutations in TRNT1 caused reduced levels of full-length TRNT1 protein and expression of a truncated smaller protein in both patient-specific iPSCs and iPSC-derived retinal organoids. Patient-specific iPSCs and iPSC-derived retinal organoids exhibited a deficit in autophagy, as evidenced by aberrant accumulation of LC3-II and elevated levels of oxidative stress. Autologous stem cell-based disease modeling will provide a platform for testing multiple avenues of treatment in patients suffering from TRNT1-associated RP., (Copyright © 2017. Published by Elsevier B.V.)

Purpose: To identify specific mutations causing North Carolina macular dystrophy (NCMD)., Design: Whole-genome sequencing coupled with reverse transcription polymerase chain reaction (RT-PCR) analysis of gene expression in human retinal cells., Participants: A total of 141 members of 12 families with NCMD and 261 unrelated control individuals., Methods: Genome sequencing was performed on 8 affected individuals from 3 families affected with chromosome 6-linked NCMD (MCDR1) and 2 individuals affected with chromosome 5-linked NCMD (MCDR3). Variants observed in the MCDR1 locus with frequencies <1% in published databases were confirmed using Sanger sequencing. Confirmed variants absent from all published databases were sought in 8 additional MCDR1 families and 261 controls. The RT-PCR analysis of selected genes was performed in stem cell-derived human retinal cells., Main Outcome Measures: Co-segregation of rare genetic variants with disease phenotype., Results: Five sequenced individuals with MCDR1-linked NCMD shared a haplotype of 14 rare variants spanning 1 Mb of the disease-causing allele. One of these variants (V1) was absent from all published databases and all 261 controls, but was found in 5 additional NCMD kindreds. This variant lies in a DNase 1 hypersensitivity site (DHS) upstream of both the PRDM13 and CCNC genes. Sanger sequencing of 1 kb centered on V1 was performed in the remaining 4 NCMD probands, and 2 additional novel single nucleotide variants (V2 in 3 families and V3 in 1 family) were identified in the DHS within 134 bp of the location of V1. A complete duplication of the PRDM13 gene was also discovered in a single family (V4). The RT-PCR analysis of PRDM13 expression in developing retinal cells revealed marked developmental regulation. Next-generation sequencing of 2 individuals with MCDR3-linked NCMD revealed a 900-kb duplication that included the entire IRX1 gene (V5). The 5 mutations V1 to V5 segregated perfectly in the 102 affected and 39 unaffected members of the 12 NCMD families., Conclusions: We identified 5 rare mutations, each capable of arresting human macular development. Four of these strongly implicate the involvement of PRDM13 in macular development, whereas the pathophysiologic mechanism of the fifth remains unknown but may involve the developmental dysregulation of IRX1., (Copyright © 2016 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Retinal pigment epithelium-specific 65 kDa (RPE65)-associated Leber congenital amaurosis is an autosomal recessive disease that results in reduced visual acuity and night blindness beginning at birth. It is one of the few retinal degenerative disorders for which promising clinical gene transfer trials are currently underway. However, the ability to enroll patients in a gene augmentation trial is dependent on the identification of 2 bona fide disease-causing mutations, and there are some patients with the phenotype of RPE65-associated disease who might benefit from gene transfer but are ineligible because 2 disease-causing genetic variations have not yet been identified. Some such patients have novel mutations in RPE65 for which pathogenicity is difficult to confirm. The goal of this study was to determine if an intronic mutation identified in a 2-year-old patient with presumed RPE65-associated disease was truly pathogenic and grounds for inclusion in a clinical gene augmentation trial. Sequencing of the RPE65 gene revealed 2 mutations: (1) a previously identified disease-causing exonic leucine-to-proline mutation (L408P) and (2) a novel single point mutation in intron 3 (IVS3-11) resulting in an A>G change. RT-PCR analysis using RNA extracted from control human donor eye-derived primary RPE, control iPSC-RPE cells, and proband iPSC-RPE cells revealed that the identified IVS3-11 variation caused a splicing defect that resulted in a frameshift and insertion of a premature stop codon. In this study, we demonstrate how patient-specific iPSCs can be used to confirm pathogenicity of unknown mutations, which can enable positive clinical outcomes., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Purpose: To determine which types of pediatric retinal degeneration are associated with inflammatory cells in the anterior vitreous., Design: Retrospective, observational study in humans., Methods: Retrospective chart review was performed for pediatric patients with suspected retinal degeneration presenting to a single examiner from 2008 to 2013. Age, visual acuity (VA), slit-lamp examination of anterior vitreous (SLAV), and clinical and molecular genetic diagnoses were documented. Anterior vitreous cells were graded clinically with SLAV from rare cells (1-4) to 1+ (5-9), 2+ (10-30), or 3+ (>30). Cells were also counted in magnified slit beam photographs masked to molecular diagnosis when obtainable., Main Outcome Measures: Cell counts in SLAV, best-corrected VA, and molecular and clinical diagnoses., Results: We evaluated 105 charts, 68 of which (64.8%) included SLAV data. Numerous (1+ or greater) cells were present in 22 of 68 patients (32.4%), whereas 4 of 68 (5.9%) had rare cells and 42 of 68 (61.8%) had no cells. The average age between patients with cells, no cells, and rare cells did not differ significantly (P = 0.25). The VA averaged 20/124 in patients with cells, 20/143 in patients with no cells, and 20/68 in patients with rare cells (P = 0.70). The most frequent diagnoses with cells included Bardet Biedl syndrome (BBS), Leber congenital amaurosis (LCA), and retinitis pigmentosa. The most frequent diagnoses without cells included congenital stationary night blindness (CSNB), LCA, Stargardt disease, and blue cone monochromacy., Discussion: A nonrandom subset of pediatric retinal degenerations exhibit vitritis. Cells were present in 5 of 5 BBS patients (a progressive degeneration), whereas cells were not detected in any of the 12 patients with CSNB (a stable dysfunction)., Conclusions: Studying vitritis in pediatric retinal degenerations may reveal whether inflammation accompanies progressive vision loss in certain subtypes. Potentially, inflammation could be treated. In addition, SLAV may aid in clinical diagnosis., (Copyright © 2015 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Age-related macular degeneration (AMD) is a common disease that can result in severe visual impairment. Abnormal regulation of the complement system has been implicated in its pathogenesis, and CFH polymorphisms contribute substantially to risk. How these polymorphisms exert their effects is poorly understood. We performed enzyme-linked immunosorbent assay (ELISA) analysis on young, aged, and AMD choroids to determine the abundance of the membrane attack complex (MAC) and performed immunofluorescence studies on eyes from 117 donors to evaluate the MAC in aging, early AMD, and advanced AMD. Morphometric studies were performed on eyes with high- or low-risk CFH genotypes. ELISA confirmed that MAC increases significantly with aging and with AMD. MAC was localized to Bruch's membrane and the choriocapillaris and was detectable at low levels as early as 5 years of age. Hard drusen were labeled with anti-MAC antibody, but large or confluent drusen and basal deposits were generally unlabeled. Labeling of retinal pigment epithelium was observed in some cases of advanced AMD, but not in early disease. Eyes homozygous for the high-risk CFH genotype had thinner choroids than low-risk homozygotes (P < 0.05). These findings suggest that increased complement activation in AMD and in high-risk genotypes can lead to loss of endothelial cells in early AMD. Treatments to protect the choriocapillaris in early AMD are needed.

Teacher education programs in the United States face increasing pressure to demonstrate their effectiveness through pupils' learning gains in classrooms where program graduates teach. The link between teacher candidates' learning in teacher education programs and pupils' learning in K-12 classrooms implicit in the policy discourse suggests a one-to-one correspondence. However, the logical steps leading from what teacher candidates have learned in their programs to what they are doing in classrooms that may contribute to their pupils' learning are anything but straightforward. In this paper, we argue that the logic model approach from scholarship on evaluation can enhance research on teacher education by making explicit the logical links between program processes and intended outcomes. We demonstrate the usefulness of the logic model approach through our own work on designing a longitudinal study that focuses on examining the process and impact of an undergraduate mathematics and science teacher education program., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Purpose: To evaluate macular and extramacular retinal anatomy in patients and carriers of X-linked retinoschisis (XLRS) using a wide-field spectral-domain optical coherence tomography (SD-OCT) imaging technique., Design: Case series., Participants: Six XLRS-affected male subjects and 3 XLRS female carriers., Methods: The subjects prospectively underwent XLRS DNA genotyping and comprehensive ophthalmic examination, including visual acuity, 30-2 Humphrey visual field, fundus photography, and wide-field SD-OCT, a montage technique to generate SD-OCT images spanning approximately 50 degrees horizontally and 35 degrees vertically of the posterior pole., Main Outcome Measures: Distribution and location of schisis cavities., Results: Among male subjects affected by XLRS, asymmetric bilateral schisis was seen in all eyes imaged with montage SD-OCT (11 eyes). Wide-field OCT images demonstrated schisis cavities only in the central macula in 6 eyes (55%), throughout the macula extending to the outside of the temporal arcades in 3 eyes (27%), and throughout the macula extending nasal to the optic nerve in 2 eyes (18%). Cystoid spaces accounting for macular splitting were present in the inner nuclear layer (INL) in all 11 eyes and in the outer nuclear layer (ONL) in 4 eyes. A few small cysts were seen parafoveally in the ganglion cell layer (GCL) or nerve fiber layer (NFL) in 4 eyes. Subclinical extramacular schisis spaces were seen (n=5 eyes) within the INL in 1 eye, the ONL in 1 eye, the INL/GCL/NFL in 1 eye, the ONL/GCL/NFL in 1 eye, and the INL/ONL/GCL/NFL in 1 eye. Schisis was rarely seen nasal to the optic nerve (2 eyes). Central/paracentral visual field defects were seen in 9 eyes. Female carriers did not show schisis on examination or OCT., Conclusions: Wide-field SD-OCT is a useful tool for evaluating complex retinal anatomy. In patients with XLRS, the foveomacular schisis was seen most frequently in the INL. Subclinical extramacular schisis was seen in 45% of eyes and was equally prevalent in the INL, ONL, and GCL/FNL. The GCL/FNL cystoid spaces were small and seen near the fovea and the arcades only. Carriers were schisis-free., Financial Disclosure(s): The author(s) have no proprietary or commercial interest in any materials discussed in this article., (Copyright © 2013 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Genetic testing can make a very positive impact on individuals and families affected with inherited eye disease in a number of ways. When properly performed, interpreted, and acted on, genetic tests can improve the accuracy of diagnoses and prognoses, can improve the accuracy of genetic counseling, can reduce the risk of disease occurrence or recurrence in families at risk, and can facilitate the development and delivery of mechanism-specific care. However, like all medical interventions, genetic testing has some specific risks that vary from patient to patient. For example, the results of a genetic test can affect a patient's plans to have children, can create a sense of anxiety or guilt, and can even perturb a patient's relationships with other family members. For these reasons, skilled counseling should be provided to all individuals who undergo genetic testing to maximize the benefits and minimize the risks associated with each test., (Copyright © 2012 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Purpose: Bardet-Biedl syndrome is a pleiotropic multiple anomaly syndrome inherited in an autosomal recessive pattern. It is now known that this disorder has locus heterogeneity, with causative mutations identified in as many as 14 genes. The aim of this study was to derive locus-specific recurrence risk estimates for family members of a proband affected with Bardet-Biedl syndrome., Methods: Mutation data from 187 probands affected with Bardet-Biedl syndrome were used. The authors counted the relative proportion of families with mutations at each of 10 loci and estimated locus-specific carrier rates for mutations using Hardy-Weinberg principles and an aggregate population frequency of 1/100,000 for the phenotype. Locus-specific recurrence risks were calculated for relatives of an affected proband., Results: Locus-specific carrier frequencies range from 1/250 to 1/2200, and the risks for an offspring of the sibling of an affected individual range from 1/1,500 to 1/13,000. The estimate of this risk derived under a locus homogeneity model is 1/960., Conclusion: Variation of recurrence risks of this magnitude may have implications for genetic counseling of families with affected individuals, in particular about prenatal testing and other reproductive options. Similar analyses to determine locus-specific carrier frequencies for other phenotypes with significant locus heterogeneity may yield similarly relevant results.

Purpose: Usher syndrome is a major cause of genetic deafness and blindness. The hearing loss is usually congenital and the retinitis pigmentosa is progressive and first noticed in early childhood to the middle teenage years. Its frequency may be underestimated. Newly developed molecular technologies can detect the underlying gene mutation of this disorder early in life providing estimation of its prevalence in at risk pediatric populations and laying a foundation for its incorporation as an adjunct to newborn hearing screening programs., Methods: A total of 133 children from two deaf and hard of hearing pediatric populations were genotyped first for GJB2/6 and, if negative, then for Usher syndrome. Children were scored as positive if the test revealed > or =1 pathogenic mutations in any Usher gene., Results: Fifteen children carried pathogenic mutations in one of the Usher genes; the number of deaf and hard of hearing children carrying Usher syndrome mutations was 15/133 (11.3%). The population prevalence was estimated to be 1/6000., Conclusion: Usher syndrome is more prevalent than has been reported before the genome project era. Early diagnosis of Usher syndrome has important positive implications for childhood safety, educational planning, genetic counseling, and treatment. The results demonstrate that DNA testing for Usher syndrome is feasible and may be a useful addition to newborn hearing screening programs.

Purpose: To correlate visual acuity of patients with Leber's congenital amaurosis (LCA) and early childhood-onset retinitis pigmentosa (RP) with mutations in underlying LCA genes., Design: Multicentered retrospective observational study., Participants: After exclusion of 28 subjects, 169 patients with the diagnosis of LCA and 27 patients with early childhood-onset RP were included in the study because the underlying mutations in AIPL1, GUCY2D, RDH12, RPE65, CRX, CRB1, RPGRIP1, CEP290, LCA5, and TULP1 genes could be identified in this cohort of patients., Methods: We collected data on best-corrected visual acuity as recorded at the time of the patient's most recent visit to one of the participating ophthalmology departments. The median and range of visual acuities for each genetic subtype were calculated separately for the LCA and early childhood-onset RP groups., Main Outcome Measures: The range and median best-corrected visual acuities for each genetic subtype and age-related mean visual acuities for each genetic subtype., Results: A wide variation in visual acuity was observed in patients with LCA and RPE65, RDH12, and CRB1 mutations, whereas AIPL1, GUCY2D, CRX, and RPGRIP1 gene mutations were associated with severely decreased visual acuities beginning within the first year of life. It was also noted that patients with either an RPE65 or CRB1 mutation have progressive visual loss with advancing age. Onset of visual symptoms after infancy was associated with a relatively better visual prognosis., Conclusions: The data obtained from this study will help clinicians provide counseling on visual prognosis to patients with known mutations in LCA genes and be of value in future studies aimed at the treatment of LCA and early childhood-onset RP., (Copyright 2010 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Mutations in several dozen genes have been shown to cause inherited photoreceptor degeneration in humans and it is likely that mutations in several dozen more will eventually be identified. Careful study of these genes has provided insight into the cellular and molecular mechanisms of human photoreceptor disease and has accelerated the development of a number of different classes of therapy including: nutritional supplementation, toxin avoidance, small-molecule drugs, large-molecule drugs, gene replacement, cell replacement, and even retinal prostheses. The retina is a very favorable system for the development of novel treatments for neurodegenerative disease because of its optical and physical accessibility as well as its highly ordered structure. With several forms of treatment for inherited retinal disease in or near clinical trial, one of the greatest remaining challenges is to educate clinicians in the appropriate use of genetic testing for identifying the individuals who will be most likely to benefit from each specific modality.

Many enzymes in the pentein superfamily use a transient covalent intermediate in their catalytic mechanisms. Here we trap and determine the structure of a stable covalent adduct that mimics this intermediate using a mutant dimethylarginine dimethylaminohydrolase and an alternative substrate. The interactions observed between the enzyme and trapped adduct suggest an altered angle of attack between the nucleophiles of the first and second half-reactions of normal catalysis. The stable covalent adduct is also capable of further reaction. Addition of imidazole rescues the original hydrolytic activity. Notably, addition of other amines instead yields substituted arginine products, which arise from partitioning of the intermediate into the evolutionarily related amidinotransferase reaction pathway. The enzyme provides both selectivity and catalysis for the amidinotransferase reaction, underscoring commonalities among the reaction pathways in this mechanistically diverse enzyme superfamily. The promiscuous partitioning of this intermediate may also help to illuminate the evolutionary history of these enzymes.

Purpose: To determine the treatment potential in Leber congenital amaurosis (LCA) resulting from an RPGRIP1 (retinitis pigmentosa GTPase regulating-interacting protein 1) mutation, a form of LCA with recent gene therapy success in an animal model., Design: Case report of a rare genetic eye disease investigated for intervention potential., Participants: A 19-year-old man with LCA., Methods: We studied the retinal structure and function in an LCA patient with a novel homozygous Val1211Glu mutation in the RPGRIP1 gene using optical coherence tomography and colocalized dark-adapted thresholds., Main Outcome Measure: Optical coherence tomography results., Results: Central retinal laminar architecture was preserved, and there was a measurable outer nuclear layer. The retained retinal structure corresponded to the region of visual sensitivity. With increasing eccentricity, there was no measurable visual function, and retinal laminar disorganization suggested a remodeling process., Conclusions: The RPGRIP1-LCA patient has treatment potential for a gene replacement strategy if targeted to central, but not pericentral or peripheral, retina. The results differ from similarly studied RPE65-LCA and CRB1-LCA patients. Preclinical progress toward therapy in LCA patients warrants detailed structure-function studies in humans to determine feasibility and candidacy for clinical trials.

Objective: To determine the clinical phenotypes in carriers with probable disease-causing sequence variations in 1 of 6 genes established to cause Leber congenital amaurosis (LCA)., Design: Observational prospective comparative study., Participants: Thirty carriers with various probable disease-causing sequence variations in 1 of 6 genes known to cause LCA., Methods: After the establishment of various disease-causing sequence variations in 37 (33.6%) of 110 patients with LCA, we examined a number of carriers who were either parents or offspring and who were willing to participate in our study. Evaluations included assessment of visual acuity, slit-lamp biomicroscopy, dilated fundus examination, and full-field electroretinogram (ERG) measurements., Main Outcome Measures: Dilated fundus examination and full-field ERGs., Results: Of the 30 carriers with probable disease-causing sequence variations for LCA, 5 (16.7%) carriers had an AIPL1 variation, 4 (13.3%) CRB1, 0 (0%) CRX, 5 (16.7%) GUCY2D, 9 (30%) RPE65, and 7 (23.3%) carriers had a RPGRIP1 variation. Twenty-nine (96.7%) carriers had 20/20 or better visual acuity in their better seeing eye with correction. Drusenlike deposits were more selectively observed in carriers with mutations in the AIPL1, CRB1, RPE65, and RPGRIP1 genes, whereas mild peripheral chorioretinal atrophy was only observed in AIPL1 and RPE65 carriers. A reduced dark-adapted isolated rod ERG response and/or maximal combined cone and rod response was recorded in carriers with mutations in the AIPL1, GUCY2D, and RPGRIP1 genes. A reduced light-adapted ERG response to a single-flash and/or 32-Hz flicker was recorded in carriers with mutations in the AIPL1, CRB1, GUCY2D, and RPGRIP1 genes. Overall, our cohort of LCA carriers did not describe significant subjective visual difficulties, including nyctalopia and/or photosensitivity., Conclusions: The variation of phenotypic expression in carriers among 5 LCA genotypes indicates that there is considerable phenotypic overlap. However, phenotypic trends were noted in carriers' fundus findings and ERG responses for each genetic subtype. Observations of phenotypic associations with specific disease-causing sequence variations in carriers have potential practical value for molecular screening strategies of patients with LCA.

Purpose: To define ophthalmic findings in a family with autosomal dominant retinitis pigmentosa and a novel IMPDH1 gene mutation., Design: Genetic and observational family study., Participants: Sixteen affected members of a family with autosomal dominant retinitis pigmentosa., Methods: Ophthalmic examination, including best-corrected visual acuity (VA), slit-lamp biomicroscopy, direct and indirect ophthalmoscopy, Goldmann kinetic perimetry, and electroretinography were performed. Deoxyribonucleic acid single-strand conformation polymorphism (SSCP) analysis was done. Abnormal polymerase chain reaction products identified by SSCP analysis were sequenced bidirectionally., Results: All affected patients had the onset of night blindness within the first decade of life. Ocular findings were characterized by diffuse retinal pigmentary degenerative changes, marked restriction of peripheral visual fields, severe loss of VA, nondetectable electroretinography amplitudes, and a high frequency of posterior subcapsular lens opacities. Affected members were observed to harbor a novel IMPDH1 gene mutation., Conclusion: A novel IMPDH1 gene mutation (Arg231Pro) was associated with a severe form of autosomal dominant retinitis pigmentosa. Families affected with a severe form of this genetic subtype should be investigated for a mutation in the IMPDH1 gene.

The 1997 World Cancer Research Fund and the American Institute for Cancer Research (WCRF/AICR) report, Food, Nutrition and the Prevention of Cancer: a global perspective, has become the most authoritative statement on the topic. WCRF International has begun the process of producing its second global report on food, nutrition, physical activity, and the prevention of cancer. The process is in three stages. The first begins with the development of a suitable methodology as advised by a task force of experts. The second stage will involve the systematic collection and display of the evidence by independent review teams. The final stage will be the assessment and judgment of that evidence by an independent panel of experts responsible for the content of the report, including its conclusions and recommendations. Two major differences between this report and previous reports on the prevention of chronic diseases are that a portfolio approach to the evidence is being used in which all types of study are weighed and the process of collecting and displaying the evidence is being clearly separated from assessment and judgment. This paper outlines the methodological procedures and their development that will be applied for the second WCRF International report.

Purpose: To study the retinal degeneration in an 11 -year-old patient with Leber congenital amaurosis (LCA) caused by mutation in GUCY2D., Study Design: Comparative human tissue study., Participants: Two subjects with LCA; postmortem eye from one LCA patient and three normal donors., Methods: Clinical and visual function studies were performed between the ages of 6 and 10 years in the LCA eye donor and at age 6 in an affected sibling. Genomic DNA was screened for mutations in known LCA genes. The retina of the 11 -year-old subject with LCA was compared with normal retinas from donors age 3 days, 18 years, and 53 years. The tissues were processed for histopathologic studies and immunofluorescence with retinal cell-specific antibodies., Results: Vision in both siblings at the ages examined was limited to severely impaired cone function. Mutation in the GUCY2D gene was identified in both siblings. Histopathologic study revealed rods and cones without outer segments in the macula and far periphery. The cones formed a monolayer of cell bodies, but the rods were clustered and had sprouted neurites in the periphery. Rods and cones were not identified in the midperipheral retina. The inner nuclear layer appeared normal in thickness throughout the retina, but ganglion cells were reduced in number., Conclusions: An 11-year-old subject with LCA caused by mutant GUCY2D had only light perception but retained substantial numbers of cones and rods in the macula and far periphery. The finding of numerous photoreceptors at this age may portend well for therapies designed to restore vision at the photoreceptor level.

It is now recognized that a subset of B-cell chronic lymphocytic leukemia (CLL) is familial. The genetic basis of familial CLL is poorly understood, but recently germ line mutations in the Ataxia Telangiectasia (ATM) gene have been proposed to confer susceptibility to CLL. The evidence for this notion is, however, not unequivocal. To examine this proposition further we have screened the ATM gene for mutations in CLLs from 61 individuals in 29 families. Truncating ATM mutations, including a known ATM mutation, were detected in 2 affected individuals, but the mutations did not cosegregate with CLL in the families. In addition, 3 novel ATM missense mutations were detected. Common ATM missense mutations were not overrepresented. The data support previous observations that ATM mutation is associated with B-CLL. However, ATM mutations do not account for familial clustering of the disease.

Purpose: To describe the atypical clinical presentations of pattern dystrophy (PD) in two unrelated families with novel peripherin/RDS mutations., Design: Observational case reports and family genetic study with review of peripherin/RDS mutations., Participants: Affected and unaffected members of two families with PD., Methods: The probands of two families, as well as other family members, underwent an ophthalmologic assessment including slit-lamp biomicroscopy, applanation tonometry, and a dilated fundus examination. Goldmann visual fields and fluorescein angiography were performed, wherever appropriate. Blood samples were obtained from affected and selected unaffected members of the families for DNA analysis., Results: The proband of family 1 had an acute onset of decreased vision and a yellowish lesion in both maculae that appeared inflammatory. However, resolution of the acute lesion ultimately resulted in fundus changes more typical for PD. Moreover, the proband's sister showed more classic-appearing PD lesions. Screening of the peripherin/RDS gene for sequence variations showed a 2-bp deletion, resulting in a translational frameshift at codon 290 in affected members of the family. The proband's father, who showed this sequence variation, did not have a macular lesion. The proband of family 2 was asymptomatic and showed a fundus phenotype similar to fundus flavimaculatus. The patient had normal visual acuity and did not demonstrate a "dark choroid" on fluorescein angiography. Molecular screening showed a Gln331stop variation in the peripherin/RDS gene., Conclusions: We describe two novel mutations in the peripherin/RDS gene in two unrelated families with PD. Clinicians should recognize the atypical features that may occur in patients with PD. A suspected diagnosis of PD may be confirmed by the identification of a mutation in the peripherin/RDS gene. In isolated family members with PD, a mutation in this gene may occur even in the absence of a clinically discernible macular lesion.

Objective: To investigate the phenotype and age-related penetrance of primary open-angle glaucoma (POAG) in Australian families with the most common Myocilin mutation (Gln368STOP)., Design: Cross-sectional genetic study., Participants: Eight pedigrees carrying the Gln368STOP mutation were ascertained from 1730 consecutive cases of POAG in the Glaucoma Inheritance Study in Tasmania., Methods: Index cases and available family members were examined for signs of glaucoma, and the presence of the GLC1A Gln368STOP mutation was ascertained by single-strand conformation polymorphism analysis and subsequent direct sequencing., Results: From the eight pedigrees, 29 Gln368STOP mutation-carrying individuals with either ocular hypertension (OHT) or POAG were found, with a mean age at diagnosis of 52.4 +/- 12.9 years and a mean peak intraocular pressure (IOP) of 28.4 +/- 4.7 mmHg. A further 11 mutation carriers older than 40 years have been studied, who as yet show no signs of OHT or POAG. Within the 8 pedigrees, a further 31 individuals with OHT or POAG were identified who did not carry the Gln368STOP mutation. For these individuals the mean age at diagnosis was higher (62.3 +/- 13.7 years, P < 0.01), and the mean peak IOP was lower (25.4 +/- 6.4 mmHg, P = 0.01). For Gln368STOP carriers, age-related penetrance for OHT or POAG was 72% at age 40 years and 82% at age 65 years. A positive family history of POAG was present in all index cases. Five of the eight pedigrees had a positive family history on both maternal and paternal sides. Seven of the eight pedigrees had one or more individuals with POAG who did not carry the mutation. Eight of the 29 Gln368STOP carriers with OHT or POAG had undergone trabeculectomy., Conclusions: The GLC1A Gln368STOP mutation is associated with POAG, which in the pedigrees studied is of a younger age of onset and higher peak IOP than non-mutation glaucoma cases. In addition, Gln368STOP mutation glaucoma cases were more likely to have undergone glaucoma drainage surgery. We have not observed simple autosomal dominant inheritance patterns for POAG in these pedigrees. Other factors, as yet uncharacterized, are involved in expression of the POAG phenotype in Gln368STOP pedigrees.

Bardet-Biedl syndrome (BBS) has been shown to be a genetically heterogeneous disorder involving genes mapping to at least six known loci. One BBS gene (MKKS) has been identified and the form of the disorder caused by this gene is allelic to McKusick-Kaufman syndrome. MKKS codes for a putative chaperonin, suggesting that other BBS genes may also code for components of chaperone complexes or be substrates of chaperone function.

Background: The myocilin gene is the first glaucoma gene to be associated with primary open-angle glaucoma (POAG). The hereditary subset of POAG and the role of the myocilin gene in our population are not clearly defined. Identification of cases of hereditary glaucoma and a better appreciation of the role of the myocilin gene may allow earlier diagnosis of the disease and optimize management of those at risk for glaucoma., Methods: Patients were recruited from university glaucoma practices in the Greater Toronto area from 1996 to 1998. Pedigree analysis and DNA banking were performed for each participant. Mutational analysis of the myocilin gene by means of single-strand conformation polymorphism analysis and direct sequencing was completed for 140 probands with POAG of diverse ethnic background., Results: A total of 103 patients (55.7%) had a family history of glaucoma. Disease-causing mutations of the myocilin gene were observed in 7 (5.0%) of the 140 probands, which accounted for 6.5% (5/77) of the familial cases. Most mutations were associated with familial disease, which implies a 50% risk of transmission of a high-risk factor for glaucoma., Interpretation: The hereditary subset of POAG is significant, and heritable glaucoma should always be suspected. In spite of the diversity of the ethnic background of our subjects, the observed prevalence of myocilin gene mutations was comparable to that previously reported, and such mutations do not appear to spare any ethnic group.

Purpose: To evaluate the clinical and electrophysiologic findings in a family with two heterozygous sequence changes in the peripherin-retinal degeneration slow (RDS) gene., Methods: A family study was done of a pedigree obtained by screening for rhodopsin, peripherin/RDS, or rom-1 gene mutations in probands from families with hereditary retinal diseases. The patients consisted of three affected and four unaffected members from a family with cone dystrophy. Ophthalmoscopy, visual field testing, electroretinography, and DNA analysis were performed., Results: Denaturing gradient gel electrophoresis showed the presence of two different sequence changes in the RDS genes of this family. In three members with a retinal disease, the authors observed the substitution of phenylalanine for serine in codon 27 (serine-27-phenylalanine). The clinical and functional findings in these three patients were most consistent with autosomal-dominant cone dystrophy. Three other family members, unaffected with retinal disease, were found to show a substitution of serine for cysteine in codon 72 of the peripherin protein., Conclusion: A peripherin/RDS sequence change may produce a cone dystrophy with minimal ophthalmoscopic changes in the macula and limited peripheral degenerative changes. Caution is warranted to avoid ascribing nondisease-causing sequence polymorphisms in candidate genes as responsible for determining the development of a retinal disease phenotype.

The recent progress seen in the development of high-quality genetic markers and high-density human genetic maps is facilitating new strategies for mapping disease-causing and disease-susceptibility genes. These strategies, which include homozygosity mapping, DNA pooling, and the utilization of linkage disequilibrium, have been successfully applied to the mapping and fine mapping of several loci causing diseases segregating in genetically isolated populations.

Background: Mutations in the peripherin/retinal degeneration slow (RDS) gene have been identified in patients with retinitis pigmentosa and pattern macular dystrophy. The authors initially examined a large family affected with both peripheral and macular degeneration, inherited as an autosomal dominant trait. Screening for peripherin/RDS mutations identified a previously unreported nucleotide alteration in all of the affected individuals. Two additional families later were found to have this same mutation., Methods: DNA samples from the members of three unrelated families were screened for peripherin/RDS mutations by denaturing gradient gel electrophoresis of the polymerase chain reaction-amplified peripherin/RDS coding sequences. The sequence change that was detected was further characterized by DNA sequencing. Family members were examined and evaluated with psychophysical and electrophysiologic methods., Results: A proline to arginine mutation in codon 210 of peripherin/RDS was found in all clinically affected individuals. Macular changes included extensive geographic atrophy, pigment epithelial changes, and/or drusen. The proline to arginine mutation was not found among 100 healthy individuals, making it unlikely to be a nondisease-causing polymorphism., Conclusions: The authors identified a novel peripherin/RDS gene mutation associated with autosomal dominant retinal degeneration in patients from three different families. The largest family showed a broad variability in the expressivity of the mutation. The overlap of clinical features with those of age-related maculopathy highlights the need to consider photoreceptor-specific genes as potential factors in the etiology of the latter condition.

Purpose: Vitreoretinopathies are disorders characterized by an abnormal vitreous gel structure and associated retinal changes. The authors report a pedigree with vitreous changes characteristic of the vitreoretinopathies, but with retinal pigment epithelial changes, electroretinographic abnormalities, and a clinical course distinct from previously described entities., Methods: Twenty-six family members were examined. Complete ophthalmologic examinations, electroretinography, and perimetry were performed on patients who were at genetic risk for the disease. Particular attention was given to vitreous morphology and examination of the retinal and retinal pigment epithelium (RPE)., Results: Fifteen individuals affected with an autosomal dominant vitreoretinal degeneration were identified. The disease is characterized by nyctalopia, progressive visual field loss, marked vitreous syneresis, progressive RPE atrophy, and combined traction-rhegmatogenous retinal detachments (11 patients). Thinning or "erosion" of the RPE in younger patients permits increased visualization of the choroidal vessels. In advanced conditions, equatorial areas are seen that appear clinically devoid of RPE, with extensive posterior atrophy in older patients. Diffuse rod-cone dysfunction is demonstrated by electroretinography. High myopia, epiphyseal dysplasia, orofacial anomalies, and systemic manifestations characteristic of other vitreoretinopathies are not present., Conclusion: The authors describe an entity clinically distinct from other vitreoretinopathies. The disease is characterized by pronounced vitreous abnormalities, complicated retinal detachments, and a progressive pigmentary retinopathy. The most unusual and constant feature is the progressive change in RPE with concurrent visual field constriction and electroretinographic abnormalities. Because the RPE initially seems normal and progressively thins or "erodes" in the equatorial periphery, the descriptive name "erosive" vitreoretinopathy is proposed.

Background: Juvenile glaucoma is an uncommon form of open-angle glaucoma that is usually recognized during childhood or early adulthood and which often has a strong family history., Methods: The authors clinically characterized a large multigeneration family with autosomal-dominant, juvenile-onset, open-angle glaucoma. Linkage analysis with short tandem repeat polymorphisms was used to evaluate the Rieger's syndrome locus as the site of the disease-causing mutation., Results: Forty members of a family with a five-generation history of open-angle glaucoma were examined. Clinical data were available from an additional five individuals, three of whom were decreased. Older family members provided limited information about the visual history of five other deceased individuals in the first three generations. Fifty-nine people were at 50% risk of harboring the disease-causing mutation; and of these, 30 were affected with glaucoma by examination or by family history. All affected patients had an affected parent. The average age at diagnosis was 18 years (range, 8-30 years). Affected family members tended to be myopic but lacked other ocular or systemic abnormalities. The intraocular pressures (IOPs) of affected individuals were commonly more than 50 mmHg when they were first examined. Gonioscopy showed the angles to be open, with no abnormal pigmentation, iris processes, or embryonic tissue. Topical medications were initially effective in controlling IOP, but surgery was usually required for long-term pressure control. The Rieger's syndrome locus on chromosome 4q25 was excluded as the site of the disease-causing mutation., Conclusion: Juvenile open-angle glaucoma can occur as an autosomal dominant trait with high penetrance. Genetic linkage analysis of the family reported here has the potential to identify the chromosomal location of a glaucoma-causing gene. This gene is genetically distinct from the chromosome 4 locus that was recently associated with Rieger's syndrome.

Purpose: The pathologic features of a variant of granular corneal dystrophy has been described in which the presence of lattice changes in addition to characteristic granular lesions has been documented. The authors investigated the mode of inheritance, natural history, and clinical manifestations of this dystrophy., Methods: A family with this condition was investigated, and a pedigree was established. Family members underwent ophthalmic examination, and ophthalmic history was obtained. In addition, pathologic examination of corneal tissue from affected patients was performed., Results: Similar to the four previously described cases, this family also traced its origins to Avellino, Italy. This autosomal dominant condition affected 27 of 92 family members, ranging in age from 5 to 77 years. Granular deposits were the earliest and most common manifestations. Lattice lesions were present in some patients with granular lesions. Older patients had anterior stromal haze between deposits, which impaired visual acuity. Recurrent granular deposits were noted in donor corneal tissue after penetrating keratoplasty for this condition. Pathologic examination of corneal tissue from affected patients confirmed the presence of hyaline material seen in granular dystrophy as well as fusiform deposits of amyloid, similar to those seen in lattice dystrophy type I., Conclusion: This study establishes the natural history and clinical manifestations of this condition.

Mutations in the rhodopsin gene are associated with as many as one quarter of all cases of autosomal dominant retinitis pigmentosa (RP). A number of different rhodopsin mutations have been reported but only the proline to histidine mutation in codon 23 (Pro-23-His) has been well characterized clinically. One recent report described a "sectoral" distribution of the retinal degeneration associated with this mutation, while another reported only that pigment was present in all four quadrants in 13 of 17 patients. This asymmetric distribution of pigmentation and visual field loss may prove to be an important clinical sign of a type of RP with a relatively good visual prognosis. The authors present a family with Pro-23-His rhodopsin-associated RP in which all six affected individuals had a regional distribution of the retinal degeneration in which the inferior hemisphere of the retina was most severely affected.

Twenty-eight of 61 members of a six-generation family are affected by an autosomal dominant eye disease which has not been described previously. Affected patients are asymptomatic in early adulthood, but have vitreous cells and the selective loss of the b-wave on the electroretinogram. Later, peripheral retinal scarring and pigmentation, peripheral arteriolar closure, and neovascularization of the peripheral retina at the ora serrata or occasionally neovascularization of the optic disc develop. Cystoid macular edema, vitreous hemorrhage, tractional retinal detachment, and neovascular glaucoma can cause profound visual loss. Vitrectomy reduces traction on the retina and allows for retinal reattachment. The role of argon laser photocoagulation or cryopexy in reducing the neovascular complications remains uncertain.

The youngest affected member of a family with a five-generation history of posterior amorphous corneal dystrophy underwent penetrating keratoplasty. The corneal button was studied by light and electron microscopy, representing the first pathologic description of this condition. Light microscopy demonstrated fracturing of the most posterior collagen layers of the stroma and focal attenuation of endothelial cells. Electron microscopy showed the collagen fibers in the most posterior stromal lamellae to be disorganized. Descemet's layer was interrupted by a band of collagen fibers resembling stroma, and there was loss of endothelial cells. These findings suggest a developmental abnormality in the formation of the posterior stroma and Descemet's membrane in posterior amorphous corneal dystrophy.