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Importance: This research confirms and further establishes that pathogenic variants in a fourth gene, METTL23, are associated with autosomal dominant normal-tension glaucoma (NTG)., Objective: To determine the frequency of glaucoma-causing pathogenic variants in the METTL23 gene in a cohort of patients with NTG from Iowa., Design, Setting, and Participants: This case-control study took place at a single tertiary care center in Iowa from January 1997 to January 2024, with analysis occurring between January 2023 and January 2024. Two groups of participants were enrolled from the University of Iowa clinics: 331 patients with NTG and 362 control individuals without glaucoma. Patients with a history of trauma; steroid use; stigmata of pigment dispersion syndrome; exfoliation syndrome; or pathogenic variants in MYOC, TBK1, or OPTN were also excluded., Main Outcomes and Measures: Detection of an enrichment of METTL23 pathogenic variants in individuals with NTG compared with control individuals without glaucoma., Results: The study included 331 patients with NTG (mean [SD] age, 68.0 [11.7] years; 228 [68.9%] female and 103 [31.1%] male) and 362 control individuals without glaucoma (mean [SD] age, 64.5 [12.6] years; 207 [57.2%] female and 155 [42.8%] male). There were 5 detected instances of 4 unique METTL23 pathogenic variants in patients with NTG. Three METTL23 variants-p.Ala7Val, p.Pro22Arg, and p.Arg63Trp-were judged to be likely pathogenic and were detected in 3 patients (0.91%) with NTG. However, when all detected variants were evaluated with either mutation burden analysis or logistic regression, their frequency was not statistically higher in individuals with NTG than in control individuals without glaucoma (1.5% vs 2.5%; P = .27)., Conclusion and Relevance: This investigation provides evidence that pathogenic variants in METTL23 are associated with NTG. Within an NTG cohort at a tertiary care center, pathogenic variants were associated with approximately 1% of NTG cases, a frequency similar to that of other known normal-tension glaucoma genes, including optineurin (OPTN), TANK-binding kinase 1 (TBK1), and myocilin (MYOC). The findings suggest that METTL23 pathogenic variants are likely involved in a biologic pathway that is associated with glaucoma that occurs at lower intraocular pressures.

Exfoliation syndrome is a leading cause of secondary glaucoma worldwide. Among the risk-factors for exfoliation syndrome and exfoliation glaucoma that have been investigated, a genetic association with 15q24.1 is among the most striking. The leading candidates for the causal gene at this locus are LOXL1 and/or LOXL1-AS1, but studies have not yet coalesced in establishing, or ruling out, either candidate. Here, we contribute to studies of the 15q24.1 locus by making a partially humanized mouse model in which 166 kb of human genomic DNA from the 15q24.1 locus was introduced into the mouse genome via BAC transgenesis (B6-Tg(RP11-71M11)Andm). Transgenic expression of human genes in the BAC was only detectable for LOXL1-AS1. One cohort of 34 mice (21 experimental hemizygotes and 13 non-carrier control littermates) was assessed by slit-lamp exams and SD-OCT imaging at early (1-2 months) and mid (4-5 months) time points; fundus exams were performed at 5 months of age. A second smaller cohort (3 hemizygotes) were aged extensively (>12 months) to screen for overt abnormalities. Across all genotypes and ages, 136 slit-lamp exams, 128 SD-OCT exams, and 42 fundus exams detected no overt indices of exfoliation syndrome. Quantitatively, small, but statistically significant, age-related declines in ganglion cell complex thickness and total retinal thickness were detected in the hemizygotes at 4 months of age. Overall, this study demonstrates complexity in gene regulation from the 15q24.1 locus and suggests that LOXL1-AS1 is unlikely to be a monogenic cause of exfoliation syndrome but may contribute to glaucomatous retinal damage., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: M.G.A. is a paid consultant for Santen Pharmaceutical., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Mutations in the thrombospondin 1 ( THBS1 ) gene have been previously reported in primary congenital glaucoma (PCG) pedigrees that exhibit autosomal dominant inheritance with low penetrance. We sought to determine the role of THBS1 mutations in a cohort of 20 patients with PCG and 362 normal controls from Iowa using a combination of Sanger sequencing and whole exome sequencing. We detected 16 different THBS1 variants, including 4 rare, nonsynonymous variants (p.Thr611Met, p.Asn708Lys, p.Gln1089His, and p.Glu1166Lys). However, none of these variants were judged to be disease-causing mutations based on: 1) prevalence in cases and controls from Iowa, 2) prevalence in the public database gnomAD, 3) mutation analysis algorithms, and 4) THBS1 DNA sequence conservation. These results indicate THBS1 mutations are not a common cause of PCG in patients from Iowa and may be a rare cause of PCG overall., Competing Interests: Disclosure: The authors declare no conflict of interest., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Importance: The p.Asp67Tyr genetic variant in the GJA3 gene is responsible for congenital cataracts in a family with a high incidence of glaucoma following cataract surgery., Objective: To describe the clinical features of a family with a strong association between congenital cataracts and glaucoma following cataract surgery secondary to a genetic variant in the GJA3 gene (NM_021954.4:c.199G>T, p.Asp67Tyr)., Design, Setting, and Participants: This was a retrospective, observational, case series, genetic association study from the University of Iowa spanning 61 years. Examined were the ophthalmic records from 1961 through 2022 of the family members of a 4-generation pedigree with autosomal dominant congenital cataracts., Main Outcomes and Measures: Frequency of glaucoma following cataract surgery and postoperative complications among family members with congenital cataract due to the p.Asp67Tyr GJA3 genetic variant., Results: Medical records were available from 11 of 12 family members (7 male [63.6%]) with congenital cataract with a mean (SD) follow-up of 30 (21.7) years (range, 0.2-61 years). Eight of 9 patients with congenital cataracts developed glaucoma, and 8 of 8 patients who had cataract surgery at age 2 years or younger developed glaucoma following cataract surgery. The only family member with congenital cataracts who did not develop glaucoma had delayed cataract surgery until 12 and 21 years of age. Five of 11 family members (45.5%) had retinal detachments after cataract extraction and vitrectomy. No patients developed retinal detachments after prophylactic 360-degree endolaser., Conclusions and Relevance: The GJA3 genetic variant, p.Asp67Tyr, was identified in a 4-generation congenital cataract pedigree from Iowa. This report suggests that patients with congenital cataract due to some GJA3 genetic variants may be at especially high risk for glaucoma following cataract surgery. Retinal detachments after cataract extraction in the first 2 years of life were also common in this family, and prophylactic retinal endolaser may be indicated at the time of surgery.

Purpose: The Faroe Islands are home to 50,000 genetically isolated people in the North Atlantic. The prevalence of open-angle glaucoma (OAG) in the Faroese population is unknown. Consequently, we conducted a survey to determine the prevalence of OAG in the Faroese population. We also investigated the role of known glaucoma-causing genes in Faroese OAG., Materials and Methods: We conducted a prospective survey of known and newly diagnosed glaucoma patients at the Faroese National Hospital, Landssjukrahusid, Tórshavn between October 1, 2015 to December 31, 2017. In addition we reviewed the only eye care provider in the Faroese Islands by scrutinizing electronic medical records between 2009 and June 15, 2014, October 1, 2015 and the partly overlapping prescriptions for ocular hypotensive medications in 2016 to identify patients with either a diagnosis of glaucoma, a diagnosis of ocular hypertension or a prescription for ocular hypotensive medications. Next, we prospectively confirmed diagnoses with complete eye examinations. Patient DNA samples were tested for variations in known glaucoma-causing genes [myocilin (MYOC), optineurin (OPTN), and TANK binding kinase 1 (TBK1)]., Results: We determined the age-related prevalence of OAG January 1, 2017 in individuals 40 years or older to be 10.7/1000 (1.07%) and highly age-related. A diagnosis of OAG was present in 264 patients, of whom 211 (79.9%) had primary OAG (including normal tension glaucoma), 49 (18.6%) had pseudoexfoliation glaucoma, and 4 (1.5%) had pigmentary glaucoma. Among patients receiving medications for glaucoma, nearly 50% had primary OAG, while the majority of the rest had ocular hypertension or secondary glaucoma. No disease-causing variants were detected in MYOC, OPTN, or TBK1., Conclusions: The calculated prevalence of OAG in the Faroe Islands was 1.07%. The absence of MYOC, OPTN, or TBK1 disease-causing variants in Faroese primary OAG patients suggests that a different, potentially unique set of genes may be contributing to the pathogenesis of glaucoma in this population., Competing Interests: Disclosure: The authors declare no conflict of interest., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Glaucoma is a leading cause of visual disability and blindness. Release of iris pigment within the eye, pigment dispersion syndrome (PDS), can lead to one type of glaucoma known as pigmentary glaucoma. PDS has a genetic component, however, the genes involved with this condition are largely unknown. We sought to discover genes that cause PDS by testing cohorts of patients and controls for mutations using a tiered analysis of exome data., Results: Our primary analysis evaluated melanosome-related genes that cause dispersion of iris pigment in mice (TYRP1, GPNMB, LYST, DCT, and MITF). We identified rare mutations, but they were not statistically enriched in PDS patients. Our secondary analyses examined PMEL (previously linked with PDS), MRAP, and 19 other genes. Four MRAP mutations were identified in PDS cases but not in controls (p = 0.016). Immunohistochemical analysis of human donor eyes revealed abundant MRAP protein in the iris, the source of pigment in PDS. However, analysis of MRAP in additional cohorts (415 cases and 1645 controls) did not support an association with PDS. We also did not confirm a link between PMEL and PDS in our cohorts due to lack of reported mutations and similar frequency of the variants in PDS patients as in control subjects., Conclusions: We did not detect a statistical enrichment of mutations in melanosome-related genes in human PDS patients and we found conflicting data about the likely pathogenicity of MRAP mutations. PDS may have a complex genetic basis that is not easily unraveled with exome analyses.

Purpose: To evaluate the first association specific to exudative age-related macular degeneration (AMD) located near the matrix metalloproteinase 9 ( MMP9 ) gene., Design: Genetic association study., Participants: One thousand seven hundred twelve patients with AMD (672 nonexudative, 1040 exudative) of predominantly northern European descent seeking treatment at the University of Iowa Hospitals and Clinics., Methods: We reanalyzed the International AMD Genetics Consortium (IAMDGC) data to validate the association of polymorphisms near MMP9 with exudative AMD and to identify additional associated single nucleotide polymorphisms (SNPs), especially MMP9 coding sequence SNPs. We genotyped a cohort of 1712 AMD patients from Iowa with 3 SNPs identified with our analysis of the IAMDGC cohort using commercially available real-time quantitative polymerase chain reaction (PCR) assays. Firth regression was used to measure the association between MMP9 SNP genotypes and exudative AMD in our cohort of patients from Iowa. In addition, we developed a PCR-based assay to genotype the Iowa cohort at a short tandem repeat polymorphism (STRP) at the MMP9 locus., Main Outcome Measures: Odds ratios and P values for exudative compared with nonexudative AMD patients in the Iowa cohort for MMP9 SNPs (rs4810482, rs17576, and rs17577) and STRP., Results: We identified 3 SNPs in the MMP9 locus (rs4810482, rs17576, and rs17577) that are highly associated with exudative AMD in patient cohorts of the IAMDGC. These MMP9 SNPs also are associated with exudative AMD in the cohort of 1712 AMD patients from Iowa (rs4810482: odds ratio [OR], 0.82; P  = 0.010; rs17576: OR, 0.86; P  = 0.046; and rs17577: OR, 0.80; P  = 0.041). We also genotyped the cohort of AMD patients from Iowa at rs142450006, another MMP9 polymorphism that previously was associated with exudative AMD. We detected a 4bp STRP, (TTTC) n , at the rs142450006 locus that is highly polymorphic and associated significantly with exudative AMD (OR, 0.78; P  = 0.016)., Conclusions: This study independently confirms and expands an association between the MMP9 locus and exudative AMD, further implicating a role for extracellular matrix abnormalities in choroidal neovascularization., (© 2020 by the American Academy of Ophthalmology.)

Background: Nanophthalmos has a significant genetic background and disease-causing mutations have been recently been reported in the myelin regulatory factor (MYRF) gene. We report clinical features in a patient with nanophthalmos and a Thr518Met MYRF mutation., Case Presentation: A three-year-old male was discovered to have nanophthalmos after first presenting to the emergency department for a frontal headache, eye pain, emesis, and lethargy. Imaging studies (CT and MRI) were negative except for increased posterior fossa cerebrospinal fluid. Subsequent examinations revealed nanophthalmos (short axial eye lengths 18.1 mm OD and 18.3 mm OS), microcornea, and a large crystalline lens. Peripheral chorioretinal pigment abnormalities were also observed. He experienced episodes of marked ocular hypertension (53 mmHg OD and 60 mmHg) likely due to intermittent angle closure precipitated by nanophthalmos. The ocular hypertension was responsive to topical medicines. Genetic analysis of known nanophthalmos genes MFRP and TMEM98 were negative, while a novel mutation, Thr518Met was detected in MYRF. The Thr518Met mutation was absent from 362 matched normal controls and was extremely rare in a large population database, allele frequency of 0.000024. The Thr518Met mutation altered a highly conserved amino acid in the MYRF protein and three of four algorithms suggested that this mutation is likely pathogenic. Finally, molecular modeling showed that the Thr518Met mutation is damaging to MYRF structure. Together these data suggest that the Thr518Met mutation causes nanophthalmos., Conclusions: Nanophthalmos may present at an early age with features of angle closure glaucoma and a Thr518Met mutation in MYRF was detected in a patient with nanophthalmos. Prevalence data, homology data, mutation analysis data, and protein modeling data suggest that this variant is pathogenic and may expand the phenotypic range of syndromic nanophthalmos caused by MYRF mutations to include central nervous system abnormalities (increased posterior fossa cerebrospinal fluid).

Importance: Mutations in the myocilin (MYOC) gene are the most common molecularly defined cause of primary open-angle glaucoma that typically occurs in patients with high intraocular pressures (IOP). One MYOC mutation, p.Gln368Ter, has been associated with as many as 1.6% of primary open-angle glaucoma cases that had a mean maximum recorded IOP of 30 mm Hg. However, to our knowledge, the role of the p.Gln368Ter mutation in patients with normal-tension glaucoma (NTG) with an IOP of 21 mm Hg or lower has not been investigated., Objective: To evaluate the role of the p.Gln368Ter MYOC mutation in patients with NTG., Design, Setting, and Participants: In this case-control study of the prevalence of the p.Gln368Ter mutation in patients with NTG, cohort 1 was composed of 772 patients with NTG and 2152 controls from the United States (Iowa, Minnesota, and New York) and England and cohort 2 was composed of 561 patients with NTG and 2606 controls from the Massachusetts Eye and Ear Infirmary and the NEIGHBORHOOD consortium. Genotyping was conducted using real-time polymerase chain reaction that was confirmed with Sanger sequencing, the imputation of genome-wide association study data, or an analysis of whole-exome sequence data. Data analysis occurred between April 2007 and April 2018., Main Outcomes and Measures: Comparison of the frequency of the p.Gln368Ter MYOC mutation between NTG cases and controls with the Fisher exact test., Results: Of 6091 total participants, 3346 (54.9%) were women and 5799 (95.2%) were white. We detected the p.Gln368Ter mutation in 7 of 772 patients with NTG (0.91%) and 7 of 2152 controls (0.33%) in cohort 1 (P = .03). In cohort 2, we detected the p.Gln368Ter mutation in 4 of 561 patients with NTG (0.71%) and 10 of 2606 controls (0.38%; P = .15). When the cohorts were analyzed as a group, the p.Gln368Ter mutation was associated with NTG (odds ratio, 2.3; 95% CI, 0.98-5.3; P = .04)., Conclusions and Relevance: In cohorts 1 and 2, the p.Gln368Ter mutation in MYOC was found in patients with IOPs that were 21 mm Hg or lower (NTG), although at a frequency that is lower than previously detected in patients with higher IOP. These data suggest that the p.Gln368Ter mutation may be associated with glaucoma in patients with normal IOPs as well as in patients with IOPs that are greater than 21 mm Hg.

Purpose: To both characterize the clinical features of large primary open angle glaucoma (POAG) pedigree from a village in southern India and to investigate the genetic basis of their disease., Materials and Methods: Eighty-four members of a large pedigree received complete eye examinations including slit lamp examination, tonometry, gonioscopy, and ophthalmoscopy. Some were further studied with perimetry. Those diagnosed with POAG were tested for disease-causing mutations in the myocilin and optineurin genes with Sanger sequencing., Results: Fourteen of 84 family members were diagnosed with POAG, while eight were clinically judged to be POAG-suspects. The family structure and the pattern of glaucoma in the pedigree are complex. Features of glaucoma in this pedigree include relatively early age at diagnosis (mean 50 ± 14 years) and maximum intraocular pressures ranging from 14 to 36 mm Hg with a mean of 23 mm Hg ± 6.5 mm Hg. Patients had an average central corneal thickness (mean 529 ± 37.8 microns) and moderate cup-to-disc ratios (0.74 ± 0.14). No mutations were detected in myocilin, optineurin, or TANK binding kinase 1 (TBK1)., Conclusions: We report a five-generation pedigree with a complex pattern of POAG inheritance that includes 22 POAG patients and glaucoma suspects. Although the familial clustering of POAG in this pedigree is consistent with dominant inheritance of a glaucoma-causing gene, mutations were not detected in genes previously associated with autosomal dominant glaucoma, suggesting the involvement of a novel disease-causing gene in this pedigree.

Purpose: Lacrimo-auriculo-dento-digital (LADD) syndrome is an autosomal dominant disorder displaying variable expression of multiple congenital anomalies including hypoplasia or aplasia of the lacrimal and salivary systems causing abnormal tearing and dry mouth. Mutations in the FGF10 , FGFR2 , and FGFR3 genes were found to cause some cases of LADD syndrome in prior genetic studies. The goal of this study is to identify the genetic basis of a case of LADD syndrome with glaucoma and thin central corneal thickness (CCT)., Methods: Whole exome sequencing was performed, and previously described disease-causing genes ( FGF10, FGFR2, and FGFR3 ) were first evaluated for mutations. Fifty-eight additional prioritized candidate genes were identified by searching gene annotations for features of LADD syndrome. The potential pathogenicity of the identified mutations was assessed by determining their frequency in large public exome databases; through sequence analysis using the Blosum62 matrix, PolyPhen2, and SIFT algorithms; and through homology analyses. A structural analysis of the effects of the top candidate mutation in tumor protein 63 (TP63) was also conducted by superimposing the mutation over the solved crystal structure., Results: No mutations were detected in FGF10 , FGFR2 , or FGFR3 . The LADD syndrome patient's exome data was searched for mutations in the 58 candidate genes and only one mutation was detected, an Arg343Trp mutation in the tumor protein 63 ( TP63 ) gene. This TP63 mutation is absent from the gnomAD sequence database. Analysis of the Arg343Trp mutation with Blosum62, PolyPhen2, and SIFT all suggest it is pathogenic. This arginine residue is highly conserved in orthologous genes. Finally, crystal structure analysis showed that the Arg343Trp mutation causes a significant alteration in the structure of TP63's DNA binding domain., Conclusions: We report a patient with no mutations in known LADD syndrome genes ( FGF10 , FGFR2 , and FGFR3 ). Our analysis provides strong evidence that the Arg343Trp mutation in TP63 caused LADD syndrome in our patient and that TP63 is a fourth gene contributing to this condition. TP63 encodes a transcription factor involved in the development and differentiation of tissues affected by LADD syndrome. These data suggest that TP63 is a novel LADD syndrome gene and may also influence corneal thickness and risk for open-angle glaucoma.

Duplication of the TBK1 gene is associated with 1-2% of normal tension glaucoma, a common cause of vision loss and blindness that occurs without grossly abnormal intraocular pressure. We generated a transgenic mouse that has one copy of the human TBK1 gene (native promoter and gene structure) incorporated into the mouse genome (Tg-TBK1). Expression of the TBK1 transgene in the retinae of these mice was demonstrated by real-time PCR. Using immunohistochemistry TBK1 protein was predominantly localized to the ganglion cell layer of the retina, the cell type most affected by glaucoma. More intense TBK1 labelling was detected in the retinal ganglion cells (RGCs) of Tg-TBK1 mice than in wild-type littermates. Tg-TBK1 mice exhibit the cardinal sign of glaucoma, a progressive loss of RGCs. Hemizygous Tg-TBK1 mice (with one TBK1 transgene per genome) had a 13% loss of RGCs by 18 months of age (P = 1.5 × 10-8). Homozygous Tg-TBK1 mice had 7.6% fewer RGCs than hemizygous Tg-TBK1 mice and 20% fewer RGCs than wild-type mice (P = 1.9 × 10-5) at 6 months of age. No difference in intraocular pressures was detected between Tg-TBK1 mice and wild-type littermates as they aged (P > 0.05). Tg-TBK1 mice with extra doses of the TBK1 gene recapitulate the phenotype of normal tension glaucoma in human patients with a TBK1 gene duplication. Together, these studies confirm the pathogenicity of the TBK1 gene duplication in human glaucoma and suggest that excess production of TBK1 kinase may have a role in the pathology of glaucoma., (© The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Purpose: Primary open-angle glaucoma (POAG) is a major cause of blindness and visual disability. Several genetic risk factors for POAG and optic nerve features have been identified. We measured the relative risk for glaucoma that these factors contribute to participants in the Ocular Hypertension Treatment Study (OHTS)., Design: Comparative series., Participants: One thousand fifty-seven of 1636 participants (65%) of the OHTS were enrolled in this genetics ancillary study., Methods: Samples of DNA were available from 1057 OHTS participants. Of these, 209 developed POAG (cases) and 848 did not develop glaucoma (controls) between 1994 and 2009. The frequencies of 13 risk alleles previously associated with POAG or with optic disc features in other cohorts were compared between POAG cases and controls in the OHTS cohort using analyses of variance. The 2 largest subgroups, non-Hispanic whites (n = 752; 70.7%) and blacks (n = 249, 23.7%), also were analyzed separately. The probability of glaucoma developing over the course of the OHTS was compared between participants stratified for transmembrane and coiled-coil domains 1 (TMCO1) risk alleles using Kaplan-Meier and Cox proportional hazards analyses., Main Outcome Measures: Association of POAG with known genetic factors., Results: No association was detected between the known POAG risk alleles when the OHTS cohort was examined as a whole. However, in the subgroup of non-Hispanic whites, allele frequencies at the TMCO1 locus were statistically different between cases and controls (P = 0.00028). By 13 years, non-Hispanic white participants with TMCO1 risk alleles had a 12% higher cumulative frequency of glaucoma developing than participants with no TMCO1 risk alleles. Moreover, the Cox proportional hazard analysis demonstrated that TMCO1 alleles increased relative risk comparable with that of some previously analyzed clinical measures (i.e., intraocular pressure)., Conclusions: The size of the OHTS cohort and its composition of 2 large racial subgroups may limit its power to detect some glaucoma risk factors. However, TMCO1 genotype was found to increase the risk of glaucoma developing among non-Hispanic whites, the largest racial subgroup in the OHTS cohort, at a magnitude similar to clinical predictors of disease that long have been associated with glaucoma., (Copyright © 2016 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Glaucoma is the most common cause of irreversible blindness worldwide. One subset of glaucoma, normal tension glaucoma (NTG) occurs in the absence of high intraocular pressure. Mutations in two genes, optineurin (OPTN) and TANK binding kinase 1 (TBK1), cause familial NTG and have known roles in the catabolic cellular process autophagy. TKB1 encodes a kinase that phosphorylates OPTN, an autophagy receptor, which ultimately activates autophagy. The sequestosome (SQSTM1) gene also encodes an autophagy receptor and also is a target of TBK1 phosphorylation. Consequently, we hypothesized that mutations in SQSTM1 may also cause NTG. We tested this hypothesis by searching for glaucoma-causing mutations in a cohort of NTG patients (n = 308) and matched controls (n = 157) using Sanger sequencing. An additional 1098 population control samples were also analyzed using whole exome sequencing. A total of 17 non-synonymous mutations were detected which were not significantly skewed between cases and controls when analyzed separately, or as a group (p > 0.05). These data suggest that SQSTM1 mutations are not a common cause of NTG.

Purpose: Autosomal dominant nanophthalmos is an inherited eye disorder characterized by a structurally normal but smaller eye. Patients with nanophthalmos have high hyperopia (far-sightedness), a greater incidence of angle-closure glaucoma, and increased risk of surgical complications. In this study, the clinical features and the genetic basis of nanophthalmos were investigated in two large autosomal dominant nanophthalmos pedigrees., Methods: Fourteen members of a Caucasian pedigree from the United States and 15 members of a pedigree from the Mariana Islands enrolled in a genetic study of nanophthalmos and contributed DNA samples. Twenty of 29 family members underwent eye examinations that included measurement of axial eye length and/or refractive error. The genetic basis of nanophthalmos in the pedigrees was studied with linkage analysis, whole exome sequencing, and candidate gene (i.e., TMEM98) sequencing to identify the nanophthalmos-causing gene., Results: Nine members of the pedigree from the United States and 11 members of the pedigree from the Mariana Islands were diagnosed with nanophthalmos that is transmitted as an autosomal dominant trait. The patients with nanophthalmos had abnormally short axial eye lengths, which ranged from 15.9 to 18.4 mm. Linkage analysis of the nanophthalmos pedigree from the United States identified nine large regions of the genome (greater than 10 Mbp) that were coinherited with disease in this family. Genes within these "linked regions" were examined for disease-causing mutations using exome sequencing, and a His196Pro mutation was detected in the TMEM98 gene, which was recently reported to be a nanophthalmos gene. Sanger sequencing subsequently showed that all other members of this pedigree with nanophthalmos also carry the His196Pro TMEM98 mutation. Testing the Mariana Islands pedigree for TMEM98 mutations identified a 34 bp heterozygous deletion that spans the 3' end of exon 4 in all affected family members. Neither TMEM98 mutation was detected in public exome sequence databases., Conclusions: A recent report identified a single TMEM98 missense mutation in a nanophthalmos pedigree. Our discovery of two additional TMEM98 mutations confirms the important role of the gene in the pathogenesis of autosomal dominant nanophthalmos.

Patients with a congenital optic nerve disease, cavitary optic disc anomaly (CODA), are born with profound excavation of the optic nerve resembling glaucoma. We previously mapped the gene that causes autosomal-dominant CODA in a large pedigree to a chromosome 12q locus. Using comparative genomic hybridization and quantitative PCR analysis of this pedigree, we report identifying a 6-Kbp heterozygous triplication upstream of the matrix metalloproteinase 19 (MMP19) gene, present in all 17 affected family members and no normal members. Moreover, the triplication was not detected in 78 control subjects or in the Database of Genomic Variants. We further detected the same 6-Kbp triplication in one of 24 unrelated CODA patients and in none of 172 glaucoma patients. Analysis with a Luciferase assay showed that the 6-Kbp sequence has transcription enhancer activity. A 773-bp fragment of the 6-Kbp DNA segment increased downstream gene expression eightfold, suggesting that triplication of this sequence may lead to dysregulation of the downstream gene, MMP19, in CODA patients. Lastly, immunohistochemical analysis of human donor eyes revealed strong expression of MMP19 in optic nerve head. These data strongly suggest that triplication of an enhancer may lead to overexpression of MMP19 in the optic nerve that causes CODA., (© 2015 WILEY PERIODICALS, INC.)

Importance: Normal-tension glaucoma (NTG) is a common cause of vision loss., Objective: To investigate the role of TANK binding kinase 1 (TBK1) gene duplications in NTG to gain insights into the causes of glaucoma that occurs at low intraocular pressure (IOP)., Design, Setting, and Participants: In this multicenter case-control study, we investigated patients who met the criteria for NTG, including glaucomatous optic neuropathy, visual field defects, and maximum recorded untreated IOP of 21 mm Hg or less, and matched controls. Participants (N = 755) were recruited from Southampton, United Kingdom (180 patients and 178 controls), Rochester, Minnesota (65 patients and 12 controls), New York, New York (96 patients and 16 controls), and Iowa City, Iowa (208 controls)., Main Outcomes and Measures: Detection of TBK1 gene duplications and comparison of the extent of the identified DNA that is duplicated with prior TBK1 copy number variations associated with NTG., Results: A TBK1 gene duplication was detected in 1 of 96 patients (1.0%) from New York and none of the controls. Analysis of duplication borders with comparative genome hybridization demonstrated that this patient has a novel duplication that has not been previously reported. No gene duplications were detected in any of the other cohorts of patients or controls., Conclusions and Relevance: Duplication of the TBK1 gene is a rare cause of NTG. The identification of another case of NTG attributed to TBK1 gene duplication strengthens the case that this mutation causes glaucoma.

Purpose: The gene that causes normal tension glaucoma (NTG) in a large pedigree was recently mapped to a region of chromosome 12q14 (GLC1P) that contains the genes TBK1, XPOT, RASSF3, and GNS. We sought to investigate the structure of the chromosome 12q14 duplication and explore the ocular expression of GLC1P locus genes., Methods: The location of the chromosome 12q14 duplication in this pedigree was examined with fluorescent in situ hybridization (FISH) using probes for TBK1 and GNS. The expression pattern of XPOT, TBK1, RASSF3, and GNS was investigated with immunohistochemistry of human eyes., Results: The karyotype of an NTG patient from pedigree GGO-414 was normal and FISH studies demonstrated that the duplicated DNA is organized as a tandem repeat on chromosome 12q14. Of the genes in or near the chromosome 12q14 duplication, TBK1 showed expression in the retina that is specific to the retinal ganglion cells and the retinal nerve fiber layer. Expression of RASSF3 and XPOT was relatively uniform throughout the retina, while GNS expression was expressed in a pattern consistent with Müller cells., Conclusions: Previous studies demonstrated that chromosome 12q14 duplications are associated with NTG inherited as an autosomal dominant trait. FISH studies now demonstrate that the duplicated segments are tandemly organized on chromosome 12q14 in close proximity. The specific expression of TBK1 in human retinal ganglion cells compared to the widespread pattern of expression of neighboring genes provides additional evidence that TBK1 is the glaucoma gene in the chromosome 12q14 duplication within the GLC1P locus.

Duplication of the TBK1 gene causes normal tension glaucoma (NTG); however the mechanism by which this copy number variation leads to retinal ganglion cell death is poorly understood. The ability to use skin-derived induced pluripotent stem cells (iPSCs) to investigate the function or dysfunction of a mutant gene product in inaccessible tissues such as the retina now provides us with the ability to interrogate disease pathophysiology in vitro . iPSCs were generated from dermal fibroblasts obtained from a patient with TBK1 -associated NTG, via viral transduction of the transcription factors OCT4 , SOX2 , KLF4 , and c-MYC . Retinal progenitor cells and subsequent retinal ganglion cell-like neurons were derived using our previously developed stepwise differentiation protocol. Differentiation to retinal ganglion-like cells was demonstrated via rt-PCR targeted against TUJ1, MAP2, THY1, NF200, ATOH7 and BRN3B and immunohistochemistry targeted against NF200 and ATOH7. Western blot analysis demonstrated that both fibroblasts and retinal ganglion cell-like neurons derived from NTG patients with TBK1 gene duplication have increased levels of LC3-II protein (a key marker of autophagy). Duplication of TBK1 has been previously shown to increase expression of TBK1 and here we demonstrate that the same duplication leads to activation of LC3-II. This suggests that TBK1 -associated glaucoma may be caused by dysregulation (over-activation) of this catabolic pathway.

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

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

Glaucoma is a common cause of visual disability and affects ∼1.6% of individuals over 40 years of age ( 1). Non-synonymous coding sequence variations in the ankyrin repeat and SOCS box containing gene 10 (ASB10) were recently associated with 6.0% of cases of primary open angle glaucoma (POAG) in patients from Oregon and Germany. We tested a cohort of POAG patients (n= 158) and normal control subjects (n= 82), both from Iowa, for ASB10 mutations. Our study had 80% power to detect a 4.9% mutation frequency in POAG patients. A total of 11 non-synonymous coding sequence mutations were detected in the cohort, but no association with POAG was detected when analyzed individually or as a group (P > 0.05). Furthermore, a survey of the National Heart, Lung, and Blood Institute's (NHLBI's) Exome Sequencing Project revealed that non-synonymous ASB10 mutations are present in the general population at a far higher frequency than the prevalence of POAG. These data suggest that non-synonymous mutations in ASB10 do not cause Mendelian forms of POAG.

Purpose: Analysis of mutant mouse strains and linkage analysis with human families have both demonstrated that mutations influencing the podosomal adaptor protein SH3 and PX domains 2B (SH3PXD2B) can result in a congenital form of glaucoma. Here, we use immunohistochemistry to describe localization of the SH3PXD2B protein throughout the adult human eye and test whether sequence variants in SH3PXD2B occur in multiple other forms of glaucoma., Methods: In immunohistochemical experiments, cryosections of human donor eyes were evaluated for SH3PXD2B immunoreactivity with a polyclonal antibody. In genetic experiments, exon sequences of SH3PXD2B from patients with primary congenital glaucoma (n=21), Axenfeld-Rieger syndrome (n=30), and primary open angle glaucoma (n=127) were compared to control subjects (n=89). The frequency of non-synonymous SH3PXD2B coding sequence variants were compared between patient cohorts and controls using Fisher's exact test., Results: Varying intensities of SH3PXD2B immunoreactivity were detected in almost all ocular tissues. Among tissues important to glaucoma, immunoreactivity was detected in the drainage structures of the iridocorneal angle, ciliary body, and retinal ganglion cells. Intense immunoreactivity was present in photoreceptor inner segments. From DNA analysis, a total of 11 non-synonymous variants were detected. By Fisher's Exact test, there was not a significant skew in the overall frequency of these changes in any patient cohort versus controls (p-value >0.05). Each cohort contained unique variants not detected in other cohorts or patients., Conclusions: SH3PXD2B is widely distributed in the adult human eye, including several tissues important to glaucoma pathogenesis. Analysis of DNA variants in three forms of glaucoma detected multiple variants unique to each patient cohort. While statistical analysis failed to support a pathogenic role for these variants, some of them may be rare disease-causing variants whose biologic significance warrants investigation in follow up replication studies and functional assays.

We report identification of a novel genetic locus (GLC1P) for normal tension glaucoma (NTG) on chromosome 12q14 using linkage studies of an African-American pedigree (maximum non-parametric linkage score = 19.7, max LOD score = 2.7). Subsequent comparative genomic hybridization and quantitative polymerase chain reaction (PCR) experiments identified a 780 kbp duplication within the GLC1P locus that is co-inherited with NTG in the pedigree. Real-time PCR studies showed that the genes within this duplication [TBK1 (TANK-binding kinase 1), XPOT, RASSF3 and GNS] are all expressed in the human retina. Cohorts of 478 glaucoma patients (including 152 NTG patients), 100 normal control subjects and 400 age-related macular degeneration patients were subsequently tested for copy number variation in GLC1P. Overlapping duplications were detected in 2 (1.3%) of the 152 NTG subjects, one of which had a strong family history of glaucoma. These duplications defined a 300 kbp critical region of GLC1P that spans two genes (TBK1 and XPOT). Microarray expression experiments and northern blot analysis using RNA obtained from human skin fibroblast cells showed that duplication of chromosome 12q14 results in increased TBK1 and GNS transcription. Finally, immunohistochemistry studies showed that TBK1 is expressed in the ganglion cells, nerve fiber layer and microvasculature of the human retina. Together, these data link the duplication of genes on chromosome 12q14 with familial NTG and suggest that an extra copy of the encompassed TBK1 gene is likely responsible for these cases of glaucoma. However, animal studies will be necessary to rule out a role for the other duplicated or neighboring genes.

Age-related macular degeneration (AMD) is the most common cause of irreversible visual loss in the developed world. Previous studies have demonstrated that the c.1204T>C, p.Tyr402His allelic variant in the complement factor H (CFH) gene is associated with an approximately three-fold increased risk for AMD in Caucasians of predominantly European descent. Both the prevalence as well as the phenotypic spectrum of AMD varies widely among persons of different ethnicities. We hypothesized that populations with a lower prevalence of AMD might also have a lower prevalence of the CFH risk allele. In this study we sought to determine the frequency of this sequence variant in control populations of Caucasians, African Americans, Hispanics, Somalis, and Japanese. Normal control populations were assembled for each ethnic group: Caucasian (n=148), Somali (n=128), African American (n=75), Hispanic (n=81), and Japanese (n=82). Individuals were genotyped using a restriction digest assay and the frequency of the C allele at nucleotide position 1204 of the CFH gene was determined. A bioinformatic approach was used to identify SNPs in linkage disequilibrium with rs1061170 (c.1204T>C, p.Tyr402His) from the human haplotype map project database (HapMap) in order to validate the findings. We found widely discordant frequencies of the risk allele between some of the different ethnic groups: Japanese 0.07+/-0.02, Hispanics 0.17+/-0.03, African-Americans 0.35+/-0.04, Caucasians 0.34+/-0.03, and Somalis 0.34+/-0.03. Allele frequencies generated by analysis of the HapMap database were consistent with these findings. This study suggests that there are other yet unidentified genetic factors important in the pathogenesis of AMD that may mitigate the effects of c.1204T>C, p.Tyr402His variant., ((c) 2006 Wiley-Liss, Inc.)

Purpose: To investigate the association of sequence variations in the optineurin (OPTN) gene in patients with open-angle glaucoma., Design: Prospective case control study., Methods: The OPTN gene was screened for sequence variations using a combination of single-strand conformational polymorphism analysis and automated DNA sequencing. A total of 1,299 subjects (1048 glaucoma patients and 251 controls) were screened for variations in the four portions of the gene that had been previously associated with glaucoma. A subset of these subjects (376 patients and 176 controls) was screened for variations in the entire coding sequence. Twenty-four percent of the patients and 35% of the controls were Japanese, whereas the remainder were predominantly Caucasian. Allele frequencies were compared with the Fisher exact test., Results: The OPTN sequence variations were not significantly associated with any form of high-tension open-angle glaucoma. One proband with familial normal-tension glaucoma was found to harbor the previously reported Glu50Lys variation. Another previously reported change, Met98Lys, was associated with normal-tension glaucoma in Japanese but not in Caucasian patients., Conclusions: This study provides some additional evidence for the association of the Glu50Lys OPTN sequence variation with familial normal tension glaucoma. However, because familial normal-tension glaucoma is so rare, this change seems to be responsible for less than 0.1% of all open-angle glaucoma. The Arg545Gln variation is likely to be a nondisease-causing polymorphism. The Met98Lys change may be associated with a fraction of normal-tension glaucoma in patients of Japanese ethnicity.

Setting: A major out-patient tuberculosis clinic in Nairobi, Kenya., Objective: To ascertain the cost-effectiveness of the polymerase chain reaction (PCR) for the diagnosis of tuberculosis in an urban setting in a developing country., Design: A cost-effectiveness analysis of PCR and direct smear microscopy examination based on theoretical modelling. The cost-effectiveness was expressed in costs per correctly diagnosed tuberculosis patient for each of the two diagnostic techniques. Data were obtained from the literature, from the staff and the register at the health facility and from structured interviews with patients. Assumptions were made when no data were available., Results: The PCR is expected to be more specific and sensitive than the routine procedure for diagnosis, but it is also more costly. The routine procedure based on direct smear microscopy turned out to be 1.8 times as cost-effective as PCR., Conclusion: It is concluded that the PCR method can potentially be a cost-effective screening procedure for tuberculosis, provided that the largest contributing cost component, the costs of the PCR-kit, can be reduced substantially.

A facility-based assessment (FBA) was done to evaluate a comprehensive leprosy training program in Nepal. The training course was developed to prepare the Basic Health Services staff for integrated leprosy work. FBA is a coordinated set of data collection activities designed to determine the extent to which patients are properly diagnosed, treated, and cared for in the treatment facility. During the present evaluation, the data collection activities included: observation of health worker performance, exit interviews with leprosy patients, interviews with health workers, inventory of essential equipment and supplies, and collection of routine statistical data. The objectives of the training course were used as guidelines for the evaluation. Surveys and observation visits were done repeatedly and compared with a (untrained) control group. Different actors involved in leprosy care were used as informants, and different data collection methods were used which enabled cross-checking of the information. Part of the data collection activities was already routinely carried out. FBA proved to be a very useful and effective tool for the evaluation of a leprosy training program. Those parts of the training which need extra attention during the course itself as well as during refresher training and supervision visits became obvious.

The need for integration of vertical projects into the Basic Health Services (BHS) has been felt in Nepal since 1968. In 1987 it was decided to provide integrated BHS all over the country. The Nepal Leprosy Control Project (NLCP) was one of the vertical projects which had to be integrated from that year. In order to prepare the BHS staff for this new task the NLCP developed a Comprehensive Leprosy Training course. Besides adequate training, three other prerequisites for successful integration are: a) adequate supply of drugs and equipment; b) regular supervision and specialist referral facilities; and c) a well functioning BHS system in which to integrate. This article tries to assess to what extent these prerequisites have been met for leprosy control in Nepal. To do this, some results of an evaluation of the training are used as well as existing literature on the functioning of the BHS system. The first three prerequisites are not fully met, but problems and obstacles related to these are mainly due to problems in the last prerequisite: a not so well functioning BHS system. It was, therefore, recommended to continue a (semi)vertical support system of leprosy control in those districts where the BHS is not so well developed.