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Anterior segment dysgenesis describes a group of heterogeneous developmental disorders that affect the anterior chamber of the eye and are associated with an increased risk of glaucoma. Here, we report homozygous mutations in peroxidasin (PXDN) in two consanguineous Pakistani families with congenital cataract-microcornea with mild to moderate corneal opacity and in a consanguineous Cambodian family with developmental glaucoma and severe corneal opacification. These results highlight the diverse ocular phenotypes caused by PXDN mutations, which are likely due to differences in genetic background and environmental factors. Peroxidasin is an extracellular matrix-associated protein with peroxidase catalytic activity, and we confirmed localization of the protein to the cornea and lens epithelial layers. Our findings imply that peroxidasin is essential for normal development of the anterior chamber of the eye, where it may have a structural role in supporting cornea and lens architecture as well as an enzymatic role as an antioxidant enzyme in protecting the lens, trabecular meshwork, and cornea against oxidative damage.

Many genes have been suggested as candidate genes for keratoconus based on their function, their proximity to associated polymorphisms or due to the identification of putative causative variants within the gene. However, very few of these genes have been assessed for rare variation in keratoconus more broadly. In contrast, VSX1 and SOD1 have been widely assessed, however, the vast majority of studies have been small and the findings conflicting. In a cohort of Australians of European descent, consisting of 385 keratoconus cases and 396 controls, we screened 21 keratoconus candidate genes: BANP, CAST, COL4A3, COL4A4, COL5A1, FOXO1, FNDC3B, HGF, IL1A, IL1B, ILRN, IMMP2L, MPDZ, NFIB, RAB3GAP1, RAD51, RXRA, SLC4A11, SOD1, TF and VSX1. The candidate genes were sequenced in these individuals by either whole exome sequencing or targeted gene sequencing. Variants were filtered to identify rare (minor allele frequency

PURPOSE: To identify genetic risk factors contributing to central corneal thickness (CCT) in individuals from South India, a population with a high prevalence of ocular disorders. METHODS: One hundred ninety-five individuals from 15 large South Indian pedigrees were genotyped using the Omni2.5 bead array. Family-based association for CCT was conducted using the score test in MERLIN. RESULTS: Genome-wide association study (GWAS) identified strongest association for single nucleotide polymorphisms (SNPs) in the first intron of WNT7B and CCT (top SNP rs9330813; β = −0.57, 95% confidence interval CI: −0.78 to −0.36; P = 1.7 × 10−7). We further investigated rs9330813 in a Latino cohort and four independent European cohorts. A meta-analysis of these data sets demonstrated statistically significant association between rs9330813 and CCT (β = −3.94, 95% CI: −5.23 to −2.66; P = 1.7 × 10−9). WNT7B SNPs located in the same genomic region that includes rs9330813 have previously been associated with CCT in Latinos but with other ocular quantitative traits related to myopia (corneal curvature and axial length) in a Japanese population (rs10453441 and rs200329677). To evaluate the specificity of the observed WNT7B association with CCT in the South Indian families, we completed an ocular phenome-wide association study (PheWAS) for the top WNT7B SNPs using 45 ocular traits measured in these same families including corneal curvature and axial length. The ocular PheWAS results indicate that in the South Indian families WNT7B SNPs are primarily associated with CCT. CONCLUSIONS: The results indicate robust evidence for association between WNT7B SNPs and CCT in South Indian pedigrees, and suggest that WNT7B SNPs can have population-specific effects on ocular quantitative traits.

Aims. Genes of the 5-lipoxygenase pathway are compelling candidates for atherosclerosis. We hypothesize that polymorphisms inALOX12, ALOX15, ALOX5, andALOX5APgenes are associated with subclinical atherosclerosis in multiple vascular beds.Methods. Families with two or more siblings with type 2 diabetes and their nondiabetic siblings were studied as part of the Diabetes Heart Study (DHS). European American diabetic (n=828) and nondiabetic (n=170) siblings were genotyped for SNPs in theALOX12, ALOX15, ALOX5, andALOX5APgenes. Subclinical measures of atherosclerosis (IMT, coronary (CorCP), carotid (CarCP) and aortic (AorCP) calcified plaque) were obtained.Results. Associations were observed betweenALOX12with CorCP,ALOX5with CorCP, AorCP, and IMT, andALOX5APwith CorCP and CarCP, independent of known epidemiologic risk factors. Further, lipoxygenase pathway SNPs that were associated with measures of atherosclerosis were associated with markers of inflammation (CRP, ICAM-1) and calcification (MGP).Conclusions. Polymorphisms withinALOX12, ALOX5, andALOX5APare genetically associated with subclinical atherosclerosis and with biomarkers of disease in families with type 2 diabetes. These results suggest that variants in lipoxygenase pathway genes may have pleiotropic effects on multiple components that determine risk of cardiovascular disease.

Genome-wide association studies (GWAS) have now successfully identified important genetic variants associated with many human traits and diseases. The high cost of genotyping arrays in large data sets remains the major barrier to wider utilization of GWAS. We have developed a novel method in which whole blood from cases and controls, respectively, is pooled prior to DNA extraction for genotyping. We demonstrate proof of principle by clearly identifying the associated variants for eye color, age-related macular degeneration, and pseudoexfoliation syndrome in cohorts not previously studied. Blood pooling has the potential to reduce GWAS cost by several orders of magnitude and dramatically shorten gene discovery time. This method has profound implications for translation of modern genetic approaches to a multitude of diseases and traits yet to be analyzed by GWAS, and will enable developing nations to participate in GWAS.

Pseudoexfoliation (PEX) syndrome is the commonest cause of secondary glaucoma. Many extracellular matrix proteins and elastic fibre structure components are present in the pathological PEX deposits in the anterior segment of the eye including the anterior lens capsule. Common coding variants in the lysyl oxidase-like 1 (LOXL1) gene, involved in cross-linking elastin, have been reported to be strongly associated with PEX syndrome in various human populations. The mechanism by which the LOXL1 protein contributes to the formation of PEX material is unknown. A comprehensive map of the component proteins of PEX deposits can aid the understanding of disease pathogenesis. The purpose of this study was to identify additional protein constituents of pathological PEX deposits. We employed a novel proteomics approach by performing mass spectrometry on "isolated" PEX material surgically removed from the anterior lens capsule of affected eyes. This approach led to the identification of LOXL1 protein and Apolipoprotein E (ApoE) in PEX material. Previously identified protein constituents, latent-transforming growth factor beta-binding protein-2, complement 3 and clusterin were also detected. Immunohistochemical analysis of lens capsules from affected eyes confirmed the presence of both LOXL1 and ApoE in pathological PEX deposits. ApoE is a novel component of these deposits. This is the first report where a direct analytical approach has led to the identification of LOXL1 in PEX deposits and is consistent with its detection in these deposits by immunolabelling in another recent report. LOXL1 is both genetically associated with PEX syndrome and present in pathological PEX deposits. Hence it clearly has an important and direct role in pathophysiology of the disease. In conclusion, additional as yet unknown components are present in pathological PEX deposits and mass spectrometry of "isolated" PEX material is an effective strategy for their identification.

OBJECTIVE Diabetic retinopathy is a sight-threatening microvascular complication of diabetes with a complex multifactorial pathogenesis. A systematic meta-analysis was undertaken to collectively assess genetic studies and determine which previously investigated polymorphisms are associated with diabetic retinopathy. RESEARCH DESIGN AND METHODS All studies investigating the association of genetic variants with the development of diabetic retinopathy were identified in PubMed and ISI Web of Knowledge. Crude odds ratios (ORs) and 95% CIs were calculated for single nucleotide polymorphisms and microsatellite markers previously investigated in at least two published studies. RESULTS Twenty genes and 34 variants have previously been studied in multiple cohorts. The aldose reductase (AKR1B1) gene was found to have the largest number of polymorphisms significantly associated with diabetic retinopathy. The z−2 micro satellite was found to confer risk (OR 2.33 [95% CI 1.49–3.64], P = 2 × 10−4) in type 1 and type 2 diabetes and z+2 to confer protection (0.58 [0.36–0.93], P = 0.02) against diabetic retinopathy in type 2 diabetes regardless of ethnicity. The T allele of the AKR1B1 promoter rs759853 variant is also significantly protective against diabetic retinopathy in type 1 diabetes (0.5 [0.35–0.71], P = 1.00 × 10−4), regardless of ethnicity. These associations were also found in the white population alone (P < 0.05). Polymorphisms in NOS3, VEGF, ITGA2, and ICAM1 are also associated with diabetic retinopathy after meta-analysis. CONCLUSIONS Variations within the AKR1B1 gene are highly significantly associated with diabetic retinopathy development irrespective of ethnicity. Identification of genetic risk factors in diabetic retinopathy will assist in further understanding of this complex and debilitating diabetes complication.

Aim: To investigate, in a large cohort of 2494 individuals with diabetes mellitus, whether functional single nucleotide polymorphisms in the promoter region of tumour necrosis factor ( TNF) and lymphotoxin-alpha ( LTA) genes are associated with type of diabetes or presence of diabetic retinopathy. Methods: A total of 334 type 1 diabetes and 999 type 2 diabetes participants with sight-threatening diabetic retinopathy, and 260 type 1 diabetes and 901 type 2 diabetes participants with no diabetic retinopathy or minimal non-proliferative diabetic retinopathy, were genotyped for two single nucleotide polymorphisms (rs1800629 and rs361525). Results: The A allele of rs1800629 was associated with type 1 diabetes ( p Conclusion: An association between the A allele of rs1800629 and type of diabetes was found. No association was found between two promoter variants of TNF and LTA, and diabetic retinopathy in a large cohort of Caucasian patients with type 1 diabetes and type 2 diabetes.

Primary congenital glaucoma (PCG) is a devastating eye disease and an important cause of childhood blindness worldwide. In PCG, defects in the anterior chamber aqueous humor outflow structures of the eye result in elevated intraocular pressure (IOP); however, the genes and molecular mechanisms involved in the etiology of these defects have not been fully characterized. Previously, we observed PCG-like phenotypes in transgenic mice that lack functional angiopoietin-TEK signaling. Herein, we identified rare TEK variants in 10 of 189 unrelated PCG families and demonstrated that each mutation results in haploinsufficiency due to protein loss of function. Multiple cellular mechanisms were responsible for the loss of protein function resulting from individual TEK variants, including an absence of normal protein production, protein aggregate formation, enhanced proteasomal degradation, altered subcellular localization, and reduced responsiveness to ligand stimulation. Further, in mice, hemizygosity for Tek led to the formation of severely hypomorphic Schlemm’s canal and trabecular meshwork, as well as elevated IOP, demonstrating that anterior chamber vascular development is sensitive to Tek gene dosage and the resulting decrease in angiopoietin-TEK signaling. Collectively, these results identify TEK mutations in patients with PCG that likely underlie disease and are transmitted in an autosomal dominant pattern with variable expressivity. Published version

Purpose : We aimed to determine differentially expressed genes relevant to orbital inflammation and orbital fat expansion in thyroid orbitopathy (TO) using microarray gene profiling in a case-control study. Methods : Human orbital adipose samples were obtained from individuals with active TO ( n = 12), inactive TO ( n = 21), and normal controls ( n = 21). Gene expression profiles were examined using microarray analysis and were compared between active and inactive TO, and between active TO and normal controls. Top ranked differentially expressed genes were validated by real-time RT-PCR in an additional eight active TO, 13 inactive TO, and 11 normal controls and correlated with gene set enrichment analysis (GSEA) and molecular pathways analysis. Results : Seven hundred twenty-one probes (683 genes) and 806 probes (735 genes) were significantly differentially expressed in comparing active to inactive TO and in comparing active TO to healthy controls, respectively. All selected genes were confirmed to be differentially expressed by real-time RT-PCR. Multiple top ranked genes in active versus inactive TO comparison are overrepresented by immune and inflammatory response genes. They include defensins ( DEFA1 , DEFA1B , DEFA3 ), which were overexpressed by 3.05- to 4.14-fold and TIMD4 by 4.20-fold. Markers for adipogenesis were overexpressed including SCD , FADS1 , and SCDP1 . Gene set enrichment analysis revealed dysregulation of epigenetic signatures, T-cell activation, Th1 differentiation, defensin pathway, cell adhesion, cytoskeleton organization, apoptosis, cell cycling, and lipid metabolism in active TO. Conclusions : Active TO is characterized by upregulation of genes involved in cell-mediated immune, innate immune, and inflammatory response and enhanced orbital adipogenesis. TIMD4 , DEFA1 , DEFA1B , and DEFA3 genes may be involved in the innate immune-mediated orbital inflammation in TO. Epigenetic mechanisms may play a role in the pathogenesis of TO.

Myocilin (MYOC) is a well-established primary open-angle glaucoma (POAG) risk gene, with rare variants known to have high penetrance. The most common clinically relevant risk variant, Gln368Ter, has an allele frequency of 0.1% to 0.3% in populations of European ancestry. Detection of rare MYOC variants has traditionally been conducted using Sanger sequencing. Here we report the use of genotyping arrays and imputation to assess whether rare variants including Gln368Ter can be reliably detected.A total of 1155 cases with advanced POAG and 1992 unscreened controls genotyped on common variant arrays participated in this study. Accuracy of imputation of Gln368Ter variants was compared with direct sequencing. A genome-wide association study was performed using additive model adjusted for sex and the first six principal components.We found that although the arrays we used were designed to tag common variants, we could reliably impute the Gln368Ter variant (rs74315329). When tested in 1155 POAG cases and 1992 controls, rs74315329 was strongly associated with risk (odds ratio = 15.53, P = 1.07 × 10-9). All POAG samples underwent full sequencing of the MYOC gene, and we found a sensitivity of 100%, specificity of 99.91%, positive predictive value of 95.65%, and negative predictive value of 100% between imputation and sequencing. Gln368Ter was also accurately imputed in a further set of 1801 individuals without POAG. Among the total set of 3793 (1992 + 1801) individuals without POAG, six were predicted (probability95%) to carry the risk variant.We demonstrate that some clinically important rare variants can be reliably detected using arrays and imputation. These results have important implications for the detection of clinically relevant incidental findings in ongoing and future studies using arrays.

Importance Juvenile open-angle glaucoma (JOAG) is a severe neurodegenerative eye disorder in which most of the genetic contribution remains unexplained. Objective To assess the prevalence of pathogenic CYP1B1 sequence variants in an Australian cohort of patients with JOAG and severe visual field loss. Design, Setting, and Participants For this cohort study, we recruited 160 patients with JOAG classified as advanced (n = 118) and nonadvanced (n = 42) through the Australian and New Zealand Registry of Advanced Glaucoma from January 1, 2007, through April 1, 2014. Eighty individuals with no evidence of glaucoma served as a control group. We defined JOAG as diagnosis before age 40 years and advanced JOAG as visual field loss in 2 of the 4 central fixation squares on a reliable visual field test result. We performed direct sequencing of the entire coding region of CYP1B1 . Data analysis was performed in October 2014. Main Outcomes and Measures Identification and characterization of CYP1B1 sequence variants. Results We identified 7 different pathogenic variants among 8 of 118 patients with advanced JOAG (6.8%) but none among the patients with nonadvanced JOAG. Three patients were homozygous or compound heterozygous for CYP1B1 pathogenic variants, which provided a likely basis for their disease. Five patients were heterozygous. The allele frequency among the patients with advanced JOAG (11 in 236 [4.7%]) was higher than among our controls (1 in 160 [0.6%]; P = .02; odds ratio, 7.8 [95% CI, 0.02-1.0]) or among the control population from the Exome Aggregation Consortium database (2946 of 122 960 [2.4%]; P = .02; odds ratio, 2.0 [95% CI, 0.3-0.9]). Individuals with CYP1B1 pathogenic variants, whether heterozygous or homozygous, had worse mean (SD) deviation on visual fields (−24.5 [5.1] [95% CI, −31.8 to −17.2] vs −15.6 [10.0] [95% CI, −17.1 to −13.6] dB; F 1,126 = 5.90; P = .02; partial η p 2 = 0.05) and were younger at diagnosis (mean [SD] age, 23.1 [8.4] [95% CI, 17.2-29.1] vs 31.5 [8.0] [95% CI, 30.1-33.0] years; F 1,122 = 7.18; P = .008; η p 2 = 0.06) than patients without CYP1B1 pathogenic variants. Conclusions and Relevance Patients with advanced JOAG based on visual field loss had enrichment of CYP1B1 pathogenic variants and a more severe phenotype compared with unaffected controls and patients with nonadvanced JOAG.

Primary open-angle glaucoma (POAG) is a blinding disease. Two important risk factors for this disease are a positive family history and elevated intraocular pressure (IOP), which is also highly heritable. Genes found to date associated with IOP and POAG are ABCA1, CAV1/CAV2, GAS7 and TMCO1. However, these genes explain only a small part of the heritability of IOP and POAG. We performed a genome-wide association study of IOP in the population-based Rotterdam Study I and Rotterdam Study II using single nucleotide polymorphisms (SNPs) imputed to 1000 Genomes. In this discovery cohort (n = 8105), we identified a new locus associated with IOP. The most significantly associated SNP was rs58073046 (? = 0.44, P-value = 1.87 ? 10(-8), minor allele frequency = 0.12), within the gene ARHGEF12. Independent replication in five population-based studies (n = 7471) resulted in an effect size in the same direction that was significantly associated (? = 0.16, P-value = 0.04). The SNP was also significantly associated with POAG in two independent case-control studies [n = 1225 cases and n = 4117 controls; odds ratio (OR) = 1.53, P-value = 1.99 ? 10(-8)], especially with high-tension glaucoma (OR = 1.66, P-value = 2.81 ? 10(-9); for normal-tension glaucoma OR = 1.29, P-value = 4.23 ? 10(-2)). ARHGEF12 plays an important role in the RhoA/RhoA kinase pathway, which has been implicated in IOP regulation. Furthermore, it binds to ABCA1 and links the ABCA1, CAV1/CAV2 and GAS7 pathway to Mendelian POAG genes (MYOC, OPTN, WDR36). In conclusion, this study identified a novel association between IOP and ARHGEF12.? The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Primary open-angle glaucoma is the most common optic neuropathy and an important cause of irreversible blindness worldwide. The optic nerve head or optic disc is divided in two parts: a central cup (without nerve fibers) surrounded by the neuroretinal rim (containing axons of the retinal ganglion cells). The International Glaucoma Genetics Consortium conducted a meta-analysis of genome-wide association studies consisting of 17,248 individuals of European ancestry and 6,841 individuals of Asian ancestry. The outcomes of the genome-wide association studies were disc area and cup area. These specific measurements describe optic nerve morphology in another way than the vertical cup-disc ratio, which is a clinically used measurement, and may shed light on new glaucoma mechanisms. We identified 10 new loci associated with disc area (CDC42BPA, F5, DIRC3, RARB, ABI3BP, DCAF4L2, ELP4, TMTC2, NR2F2, and HORMAD2) and another 10 new loci associated with cup area (DHRS3, TRIB2, EFEMP1, FLNB, FAM101, DDHD1, ASB7, KPNB1, BCAS3, and TRIOBP). The new genes participate in a number of pathways and future work is likely to identify more functions related to the pathogenesis of glaucoma. ? 2015

Purpose To investigate associations between single nucleotide polymorphisms (SNPs) in the VEGFC gene and the development of diabetic retinopathy (DR) in white patients with type 1 diabetes mellitus (T1DM) or type 2 diabetes mellitus (T2DM). Design Cross-sectional, case control study. Participants White patients with T1DM or T2DM (n = 2899) were recruited from ophthalmology and endocrine clinics in Australia and the United Kingdom. Patients with T2DM were required to have diabetes mellitus (DM) for at least 5 years and be receiving oral hypoglycemic treatment or insulin. Methods Participants were categorized according to their worst-ever DR grading, as having "no DR" (no history of nonproliferative DR [NPDR], proliferative DR [PDR], or diabetic macular edema [DME]) or "any DR" (further subclassified as NPDR or PDR, without or with DME). Clinical characteristics, glycemic control (hemoglobin A1c [HbA1c]), and presence of diabetic complications were determined at recruitment. Genotyping was performed for 13 VEGFC tag SNPs. Main Outcome Measures Odds ratios (ORs) were determined for associations with DR of VEGFC tag SNPs, individually and within haplotypes. Logistic regression was used to adjust for clinical covariates, including DM type, age, sex, DM duration, hypertension, nephropathy, HbA1c, and smoking. Results Participants with DM but "no DR" (n = 980) were compared with 1919 participants with DM and "any DR." Three VEGFC SNPs were associated with DR after logistic regression: rs17697419 ( P = 0.001; OR, 0.67; confidence interval [CI], 0.52–0.85), rs17697515 ( P = 0.001; OR, 0.62; CI, 0.47–0.81), and rs2333526 ( P = 0.005; OR, 0.69; CI, 0.54–0.90). rs17697515 Was also specifically associated with DME in those with T2DM ( P = 0.004; OR, 0.53; CI, 0.35–0.82). Haplotype analysis revealed 2 significantly associated haplotypes, both protective against DR development. Conclusions Significant associations were found between VEGFC tag SNPs (individually and within haplotypes) and the presence of any DR or DME in white participants with T1DM and T2DM.

Summary Elevated C-reactive protein (CRP) levels are associated with both prevalent and incident cardiovascular disease. In this study, familial aggregation was estimated, and we tested for association between serum CRP levels and polymorphisms within the CRP and APOE genes in sib-ships with type 2 diabetes mellitus, a population at increased risk for cardiovascular disease. CRP levels were determined in 461 diabetes-affected subjects from 224 sibships from the Diabetes Heart Study (DHS). Heritability estimates of CRP levels were obtained using variance component models. Genetic influence on serum CRP levels by single nucleotide polymorphisms (SNPs) in the CRP and APOE genes was evaluated by association analysis using mixed models. Subjects were Caucasian American (84%) and African-American (16%), 53% female, and had an average age of 62.2 ± 9.2 years. The median CRP level was 3.3 mg/L (range 0 to 59.3 mg/L), and estimated heritability for CRP was approximately 40%. Estimates of heritability were significantly greater than zero (P < 0.0001) and relatively constant, despite adjustments for important modifiers (age, sex, ethnicity, diabetes duration, statin-use and anti-inflammatory use) of CRP. There was no significant evidence for association of CRP levels with CRP gene SNPs; however, consistent with previous reports, there was significant evidence of association of CRP levels with polymorphisms within the APOE gene. These data indicate CRP levels are significantly influenced by genetic (and/or environmental) factors that are shared within DHS families. While the APOE locus shows evidence of contributing to CRP levels, no evidence of CRP gene polymorphism association with CRP levels was observed.

Background: To examine the contribution of mutations within the Norrie disease (NDP) gene to the clinically similar retinal diseases Norrie disease, X-linked familial exudative vitreoretinopathy (FEVR), Coat's disease and retinopathy of prematurity (ROP). Methods: A dataset comprising 13 Norrie-FEVR, one Coat's disease, 31 ROP patients and 90 ex-premature babies of

Aims Cardiovascular disease (CVD) is a major complication of Type 2 diabetes mellitus. The renin-angiotensin system (RAS) and nitric oxide production are both important regulators of vascular function and blood pressure. Genes encoding proteins involved in these pathways are candidates for a contribution to CVD in diabetic patients. We have investigated variants of the angiotensinogen (AGT), angiotensin converting enzyme (ACE), angiotensin type 1 receptor (AT1R) and endothelial nitric oxide synthase (NOS3) genes for association with subclinical measures of CVD in families with Type 2 diabetes mellitus (T2DM). Methods Atherosclerosis was measured by carotid intima-media thickness and calcification of the carotid and coronary arteries in 620 European Americans and 117 African Americans in the Diabetes Heart Study. Because of the role of these systems in blood pressure regulation, blood pressure was also investigated. Results Compelling evidence of association was not detected with any of the SNPs with any outcome measures after adjustments for covariates despite sufficient power to detect relatively small differences in traits for specific genotype combinations. Conclusions Genetic variation of the RAS and NOS3 genes do not appear to strongly influence subclinical cardiovascular disease or blood pressure in this diabetic population.

Background CD40/CD40L signaling is known to play an important role in immune response. The proteins are expressed in a variety of cell types and ligation causes cells to produce inflammatory cytokines and cellular adhesion molecules. These processes are implicated in the development and progression of atherosclerosis. Animal models demonstrate that interruption of CD40/CD40L signaling produces a more fibrous and stable atherosclerotic lesion. Methods We investigated the role of genetic variation in CD40 and CD40L genes in subclinical atherosclerosis assessed by coronary artery calcification (CAC) and carotid intima-media thickness in 620 individuals from 230 families in the DHS. Results Two single nucleotide polymorphisms in the CD40 gene (rs1535045 and rs3765459) were significantly associated with decreased CAC ( P ≤ .02) in this population. CD40L single nucleotide polymorphisms were not significantly associated. In addition, no associations with carotid intima-media thickness, carotid artery calcification, or C-reactive protein levels were detected for either gene. Conclusion Genetic variation in the CD40 gene is associated with CAC in diabetic families.

Individuals with type 2 diabetes are at increased risk of cardiovascular disease (CVD) mortality and display increased levels of subclinical CVD. Genetic variation in PTPN1, a diabetes susceptibility gene, was investigated for a role in diabetic atherosclerosis. The PTPN1 gene encodes protein tyrosine phosphatase-1B, which is ubiquitously expressed and plays a role in the regulation of several signaling pathways. Subclinical atherosclerosis was assessed in 590 Caucasian participants with type 2 diabetes in the Diabetes Heart Study using B-mode ultrasound measurement of carotid intima-media thickness (IMT) and computed tomography measurement of carotid calcified plaque (CarCP) and coronary calcified plaque (CorCP). Twenty-three single nucleotide polymorphisms (SNPs) in PTPN1 were genotyped and assessed for association with IMT, CarCP, and CorCP. A total of 12 SNPs within a block of linkage disequilibrium encompassing the coding sequence of PTPN1 were significantly associated with CorCP (P values from

Identification of podocin (NPHS2) gene mutations in African Americans with nondiabetic end-stage renal disease.BackgroundPodocin, encoded byNPHS2 and mapped to 1q25.2, is an integral membrane protein exclusively expressed in glomerular podocytes. Mutations in theNPHS2 gene cause autosomal-recessive nephrotic syndrome and have been associated with proteinuria in several populations. Evidence for linkage of end-stage renal disease (ESRD) to chromosome 1q25-31 in the region ofNPHS2 has been identified in a genome-wide scan in African American (AA) siblings.MethodsTo investigate the potential role of this gene in ESRD, we sequenced all coding regions and approximately 2kb of upstream promoter sequence ofNPHS2 in 96 unrelated AA nondiabetic ESRD cases and 96 healthy population-based AA controls, and assessed several single nucleotide polymorphisms (SNPs) for association in a larger case-control sample.ResultsFifty-five variants were identified with minor allele frequencies ranging from

Albuminuria demonstrates significant heritability in multiply affected hypertensive and diabetic families. The role of endothelial nitric oxide synthase (eNOS) gene variants as risk factors for albuminuria was investigated in 590 European American siblings from 230 families in the Diabetes Heart Study. Two polymorphisms in the eNOS gene (T-786C in the promoter region and Glu298Asp in exon 7) were genotyped. Albuminuria was defined as an albumin:creatinine ratio (ACR) >/=17 mg/g in men and >/=25 mg/g in women. Tests of association were based on generalized estimating equations, and tests of linkage disequilibrium were based on the quantitative pedigree disequilibrium test. A total of 83% of participants had type 2 diabetes. The median ACR was 10.7 mg/g (interquartile range, 5.1 to 32.8), and 34% (202 of 590) of participants had an elevated ACR. The eNOS -786C allele but not the Glu298Asp was associated with increased ACR (31% increase in absolute level of ACR for each additional copy of the -786C allele; P < 0.0001) and a higher risk for albuminuria (odds ratio, 1.55 for each additional copy of the -786C allele; P = 0.0005). Adjustment for the nongenetic determinants of ACR had no significant effect on the results; neither did stratification by gender, presence of diabetes, and the Glu298Asp genotype. Results were confirmed by quantitative pedigree disequilibrium test analysis and were consistent with haplotype analysis. The -786C eNOS variant was positively correlated with a higher prevalence and a greater degree of albuminuria in European American families in both diabetic and nondiabetic family members.

An elderly patient with no abnormal bleeding presented with prolongation of the activated partial thromboplastin time (aPTT). Preincubation of plasma with aPTT reagent caused shortening of the abnormal clotting time. Plasma prekallikrein (PK) activity and antigen were

There are many advantages to understanding the genetics of human disease. Genetic markerscan be used to calculate the risk of developing a disease, and elucidation of genetic risk factors can pinpointthe molecular aetiology of disease, which can facilitate the development of targeted therapies. Diabeticretinopathy (DR) is a common complication of diabetes that has a significant impact on quality of life.It has a clear genetic component, but determination of the genetic risk factors has proven difficult. Todate, genome-wide studies for DR have been conducted on relatively small patient cohorts comparedto other complex eye diseases and replication of genetic findings has been limited. The disease is highlyheterogeneous, confounding attempts to classify patients into appropriate groups for genetic analysis andmaking direct comparisons between studies challenging. Future studies to determine the genetic causes ofDR will need to focus on larger sample sizes, detailed phenotyping and appropriate classification of patients.Global co-operation and meta-analyses combining data from multiple studies will be critical to the discoveryof genetic risk loci for DR.

Primary Open Angle Glaucoma (POAG) is a common neurodegenerative disease characterized by the selective and gradual loss of retinal ganglion cells (RGCs). Aging and increased intraocular pressure (IOP) are glaucoma risk factors; nevertheless patients deteriorate at all levels of IOP, implying other causative factors. Recent evidence presents mitochondrial oxidative phosphorylation (OXPHOS) complex-I impairments in POAG. Leber Hereditary Optic Neuropathy (LHON) patients suffer specific and rapid loss of RGCs, predominantly in young adult males, due to complex-I mutations in the mitochondrial genome. This study directly compares the degree of OXPHOS impairment in POAG and LHON patients, testing the hypothesis that the milder clinical disease in POAG is due to a milder complex-I impairment. To assess overall mitochondrial capacity, cells can be forced to produce ATP primarily from mitochondrial OXPHOS by switching the media carbon source to galactose. Under these conditions POAG lymphoblasts grew 1.47 times slower than controls, whilst LHON lymphoblasts demonstrated a greater degree of growth impairment (2.35 times slower). Complex-I enzyme specific activity was reduced by 18% in POAG lymphoblasts and by 29% in LHON lymphoblasts. We also assessed complex-I ATP synthesis, which was 19% decreased in POAG patients and 17% decreased in LHON patients. This study demonstrates both POAG and LHON lymphoblasts have impaired complex-I, and in the majority of aspects the functional defects in POAG were milder than LHON, which could reflect the milder disease development of POAG. This new evidence places POAG in the spectrum of mitochondrial optic neuropathies and raises the possibility for new therapeutic targets aimed at improving mitochondrial function.

PURPOSE:To identify biological processes associated with POAG and its subtypes, high-tension (HTG) and normal-tension glaucoma (NTG), by analyzing rare potentially damaging genetic variants. METHODS:A total of 122 and 65 unrelated HTG and NTG participants, respectively, with early onset advanced POAG, 103 non-glaucoma controls and 993 unscreened ethnicity-matched controls were included in this study. Study participants without myocilin disease-causing variants and non-glaucoma controls were subjected to whole exome sequencing on an Illumina HiSeq2000. Exomes of participants were sequenced on an Illumina HiSeq2000. Qualifying variants were rare in the general population (MAF < 0.001) and potentially functionally damaging (nonsense, frameshift, splice or predicted pathogenic using SIFT or Polyphen2 software). Genes showing enrichment of qualifying variants in cases were selected for pathway and network analysis using InnateDB. RESULTS:POAG cases showed enrichment of rare variants in camera-type eye development genes (p = 1.40×10-7, corrected p = 3.28×10-4). Implicated eye development genes were related to neuronal or retinal development. HTG cases were significantly enriched for key regulators in the unfolded protein response (UPR) (p = 7.72×10-5, corrected p = 0.013). The UPR is known to be involved in myocilin-related glaucoma; our results suggest the UPR has a role in non-myocilin causes of HTG. NTG cases showed enrichment in ion channel transport processes (p = 1.05×10-4, corrected p = 0.027) including calcium, chloride and phospholipid transporters involved in plasma membrane homeostasis. Network analysis also revealed enrichment of the MHC Class I antigen presentation pathway in HTG, and the EGFR1 and cell-cycle pathways in both HTG and NTG. CONCLUSION:This study suggests that mutations in eye development genes are enriched in POAG. HTG can result from aberrant responses to protein misfolding which may be amenable to molecular chaperone therapy. NTG is associated with impaired plasma membrane homeostasis increasing susceptibility to apoptosis.

Primary open angle glaucoma (POAG), a major cause of blindness worldwide, is a complex disease with a significant genetic contribution. We performed Exome Array (Illumina) analysis on 3504 POAG cases and 9746 controls with replication of the most significant findings in 9173 POAG cases and 26 780 controls across 18 collections of Asian, African and European descent. Apart from confirming strong evidence of association at CDKN2B-AS1 (rs2157719 [G], odds ratio [OR] = 0.71, P = 2.81 × 10(-33)), we observed one SNP showing significant association to POAG (CDC7-TGFBR3 rs1192415, ORG-allele = 1.13, Pmeta = 1.60 × 10(-8)). This particular SNP has previously been shown to be strongly associated with optic disc area and vertical cup-to-disc ratio, which are regarded as glaucoma-related quantitative traits. Our study now extends this by directly implicating it in POAG disease pathogenesis.

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Purpose To investigate the presence of TBK1 copy number variations in a large, well-characterized Australian cohort of patients with glaucoma comprising both normal-tension glaucoma and high-tension glaucoma cases. Design A retrospective cohort study. Methods DNA samples from patients with normal-tension glaucoma and high-tension glaucoma and unaffected controls were screened for TBK1 copy number variations using real-time quantitative polymerase chain reaction. Samples with additional copies of the TBK1 gene were further tested using custom comparative genomic hybridization arrays. Results Four out of 334 normal-tension glaucoma cases (1.2%) were found to carry TBK1 copy number variations using quantitative polymerase chain reaction. One extra dose of the TBK1 gene (duplication) was detected in 3 normal-tension glaucoma patients, while 2 extra doses of the gene (triplication) were detected in a fourth normal-tension glaucoma patient. The results were further confirmed by custom comparative genomic hybridization arrays. Further, the TBK1 copy number variation segregated with normal-tension glaucoma in the family members of the probands, showing an autosomal dominant pattern of inheritance. No TBK1 copy number variations were detected in 1045 Australian patients with high-tension glaucoma or in 254 unaffected controls. Conclusion We report the presence of TBK1 copy number variations in our Australian normal-tension glaucoma cohort, including the first example of more than 1 extra copy of this gene in glaucoma patients (gene triplication). These results confirm TBK1 to be an important cause of normal-tension glaucoma, but do not suggest common involvement in high-tension glaucoma.

Primary open-angle glaucoma (POAG) is a major cause of irreversible blindness worldwide. We performed a genome-wide association study in an Australian discovery cohort comprising 1,155 cases with advanced POAG and 1,992 controls. We investigated the association of the top SNPs from the discovery stage in two Australian replication cohorts (932 cases and 6,862 controls total) and two US replication cohorts (2,616 cases and 2,634 controls total). Meta-analysis of all cohorts identified three loci newly associated with development of POAG. These loci are located upstream of ABCA1 (rs2472493[G], odds ratio (OR) = 1.31, P = 2.1 × 10(-19)), within AFAP1 (rs4619890[G], OR = 1.20, P = 7.0 × 10(-10)) and within GMDS (rs11969985[G], OR = 1.31, P = 7.7 × 10(-10)). Using RT-PCR and immunolabeling, we show that these genes are expressed within human retina, optic nerve and trabecular meshwork and that ABCA1 and AFAP1 are also expressed in retinal ganglion cells.

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The purpose of this review is to compare the prevalence of diabetic retinopathy (DR) between Indigenous and non-Indigenous Australians with Diabetes Mellitus (DM). Australian DR prevalence data from 6 Indigenous studies (n = 2865) and 5 non-Indigenous studies (n = 9801) conducted between 1985 and 2013 were included for analysis. Estimated prevalence of any DR among Indigenous Australians with DM was 23.4% compared with 28.9% for non-Indigenous Australians (χ(2) = 26.9, P 0.001). In studies performed after 1990, a significantly higher rate of diabetic macular edema was found in Indigenous compared with non-Indigenous Australians with DM (7.6% versus 4.9%, χ(2) = 6.67, P = 0.01). Although there are limitations in comparing these studies, one explanation for the observed data could be a model in which Indigenous Australians are relatively resistant to early stage DR, but with a subset progressing to sight threatening DR due to individual genetic and environmental susceptibility factors coupled with poor glycemic control.

OBJECTIVE Aldose reductase (ALR) is involved in diabetic microvascular damage via the polyol pathway. A recent meta-analysis found genetic variation in the ALR gene (AKR1B1) to be significantly associated with diabetic retinopathy (DR). We investigated the genetic association of AKR1B1 with DR. RESEARCH DESIGN AND METHODS The study enrolled 909 individuals with diabetes. Participants were genotyped for an AKR1B1 (CA)n microsatellite and 14 tag single nucleotide polymorphisms, and ophthalmological assessment was performed. RESULTS A total of 514 individuals were found to have DR. rs9640883 was significantly associated with DR (P = 0.0005). However, AKR1B1 variation was not independently associated with DR development after adjusting for relevant clinical parameters. rs9640883 was associated with duration of diabetes (P = 0.002). CONCLUSION Many previous reports have failed to account for known risk factors for DR. The commonly reported association of AKR1B1 with DR may be due to an association of the gene with younger age at onset of diabetes.

The X chromosome is unique, both in terms of functional expression and evolutionary history. Population frequencies for a minority of conditions, such as mental retardation, are directly related to the X chromosome. To explore these ideas, we investigated the general role of the X chromosome in ocular genetics through bioinformatic analysis of the distribution of eye-related genes in the human genome. The proportion of eye-disease loci located on the X chromosome compared to those eye diseases with an autosomal locus was calculated. The resultant figure (3.47) is lower than that calculated for mental retardation (9.74). A comparison between the number of X chromosome genes expressed in the eye compared to the number of autosomal genes expressed in the eye also did not reveal significant differences. Of all genes expressed in the eye, 2.9% are thought to be located on the X chromosome, fewer than found for the larger autosomes (which range from 10.1% to 3.6%). The eye's functional genetic components appear to be dispersed throughout the human genome, possibly to ensure survival in the event of significant cytogenetic derangement.

MYOC gene variants are associated with autosomal dominant primary open angle glaucoma (POAG). In this study, we describe a previously unreported MYOC variant segregating with a POAG phenotype in an Australian family. Two individuals affected with POAG and three unaffected individuals from the same family were recruited through the Australian and New Zealand Registry of Advanced Glaucoma (ANZRAG). Direct sequencing of all MYOC coding exons identified the novel heterozygous single nucleotide transition MYOC:c.1119G>A, p.(Trp373), predicted to encode an aberrant truncated MYOC protein in two affected siblings. Two unaffected siblings and an unaffected niece were negative for the MYOC sequence variant.

This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited., It has recently been shown that there are highly significant associations for common single nucleotide polymorphisms (SNPs) near the CDKN2B-AS1 gene region at the 9p21 locus with primary open angle glaucoma (POAG), a leading cause of irreversible blindness. This gene region houses the CDKN2B/p15INK4B , CDKN2A/p16INK4A and p14ARF (rat equivalent, p19ARF) tumour suppressor genes and is adjacent to the S-methyl-59-thioadenosine phosphorylase (MTAP) gene. In order to understand the ocular function of these genes and, therefore, how they may be involved in the pathogenesis of POAG, we studied the distribution patterns of each of their products within human and rat ocular tissues. MTAP mRNA was detected in the rat retina and optic nerve and its protein product was localised to the corneal epithelium, trabecular meshwork and retinal glial cells in both human and rat eyes. There was a very low level of p16INK4A mRNA present within the rat retina and slightly more in the optic nerve, although no protein product could be detected in either rat or human eyes with any of the antibodies tested. P19ARF mRNA was likewise only present at very low levels in rat retina and slightly higher levels in the optic nerve. However, no unambiguous evidence was found to indicate expression of specific P19ARF/p14ARF proteins in either rat or human eyes, respectively. In contrast, p15INK4B mRNA was detected in much higher amounts in both retina and optic nerve compared with the other genes under analysis. Moreover, p15INK4B protein was clearly localised to the retinal inner nuclear and ganglion cell layers and the corneal epithelium and trabecular meshwork in rat and human eyes. The presented data provide the basis for future studies that can explore the roles that these gene products may play in the pathogenesis of glaucoma and other models of optic nerve damage.

Author version made available in accordance with the publisher's policy., A mutation miR-184(+57C>T) in the seed region of miR-184 (encoded by MIR184 [MIM*613146]) results in familial severe keratoconus combined with early-onset anterior polar cataract and endothelial dystrophy, iris hypoplasia, congenital cataract, and stromal thinning (EDICT) syndrome (MIM#614303). In order to investigate the phenotypic spectrum resulting from MIR184 mutation, MIR184 was sequenced in a keratoconus cohort of mixed ethnicity and a Chinese axial myopia cohort. Sequencing of MIR184 was performed in 780 unrelated keratoconus patients and 96 unrelated Han southern Chinese subjects with axial myopia. Effects of identified mutations on RNA secondary structure were predicted computationally using mFold and RNAFold algorithms. MIR184 amplicons from patients harboring mutations were cloned and transfected into human embryonic kidney 293T (HEK293T) cells, and mature mutant miR-184 expression was analyzed by stem-loop real-time quantitative PCR (RT-qPCR). Two novel heterozygous substitution mutations in MIR184 were identified in the two patients with isolated keratoconus: miR-184(+8C>A) and miR-184(+3A>G). Computational modeling predicted that these mutations would alter the miR-184 stem-loop stability and secondary structure. Ex vivo miR-184 expression analysis demonstrated that miR-184(+8C>A) almost completely repressed the expression of miR-184 (P = 0.022), and miR-184(+3A>G) reduced the expression of miR-184 by approximately 40% (P = 0.002). There was no significant association of rs41280052, which lies within the stem-loop of miR-184, with keratoconus. No MIR184 mutations were detected in the axial myopia cohort. Two novel heterozygous substitution mutations in MIR184 were identified in two patients with isolated keratoconus: miR-184(+8C>A) and miR-184(+3A>G). Mutations in MIR184 are a rare cause of keratoconus and were found in 2 of 780 (0.25%) cases., Supported by Fight for Sight (United Kingdom; JL, CEW); The Research and Development Office, Northern Ireland (RRG Grant 4.46; CEW); Biotechnology and Biological Sciences Research Council, United Kingdom (Grant BB/H005498/1; JG-F, DAS); National Health and Medical Research Council of Australia (KPB, JEC); ALCON India (GG, MD, PS); and The Aravind Eye Care System (GG, MD, PS). JL is a Fight for Sight PhD student.

Diabetic retinopathy (DR) is a blinding disease of increasing prevalence that is caused by a complex interplay of genetic and environmental factors. Here we describe the patient recruitment methodology, case and control definitions, and clinical characteristics of a study sample to be used for genome-wide association analysis to detect genetic risk variants of DR.One thousand six hundred sixty-nine participants with either type 1 (T1) or type 2 (T2) diabetes mellitus (DM) aged 18 to 95 years were recruited in Australian hospital clinics. Individuals with T2DM had disease duration of at least 5 years and were taking oral hypoglycaemic medication, and/or insulin therapy. Participants underwent ophthalmic examination. Medical history and biochemistry results were collected. Venous blood was obtained for genetic analysis.Six hundred eighty-three diabetic cases (178 T1DM and 505 T2DM participants) with sight-threatening DR, defined as severe non-proliferative DR, proliferative DR or diabetic macular oedema were included in this analysis. Eight hundred twelve individuals with DM but no DR or minimal non-proliferative DR were recruited as controls (191 with T1DM and 621 with T2DM). The presence of sight-threatening DR was significantly correlated with DM duration, hypertension, nephropathy, neuropathy, HbA1C and body mass index. Diabetic macular oedema was associated with T2DM (P 0.001), whereas proliferative DR was associated with T1DM (P 0.001).Adoption of a case-control study design involving extremes of the DR phenotype makes this a suitable cohort, for a well-powered genome-wide association study to detect genetic risk variants for DR.

Primary open-angle glaucoma (POAG) is a genetically complex disease. Genome-wide association study (GWAS) is a particularly useful tool in the search for genetic contributions to glaucoma. Recently, chromosome 9p21 has become a major focus of research endeavour, with multiple genome-wide association studies suggesting associations to POAG. Herein, we provide a review of the chromosome 9p21 susceptibility locus as a risk factor for POAG.

Author version made available in accordance with the publisher's policy., Purpose: Recently, several studies have investigated genetic associations between Cytochrome P450 (CYP1B1), Endothelial nitric oxide synthase (eNOS) and Neurotrophin-4 (NTF4) with primary angle-closure glaucoma (PACG) in various ethnic groups. Here we investigate the association of these candidate genes with PACG in samples from Australia and Nepal. Method: A total of 235 patients with PACG (106 Nepalese and 129 Australian) and 492 controls (204 Nepalese and 288 Australian) were included. Tag single nucleotide polymorphisms (SNPs) were selected to cover the majority of common variation within the candidate genes and genotyped in DNA extracted from peripheral whole blood. Allele and haplotype analyses were conducted in PLINK. Bonferroni correction was applied for the total number of SNPs in this study (p=0.05/15=0.003) Results: In the Australian cohort, one eNOS SNP rs3793342 shows significance association with PACG in the Australian cohort after Bonferroni correction (p-value 0.003, OR 0.5 95% CI 0.3-0.8). After adjusting the results for sex and age both SNPs rs3793342 and rs7830 showed significance after Bonferroni correction (p-value of 0.001 and 0.003, respectively). The eNOS haplotype of all 7 typed SNPs showed significant association with a global p-value of 0.019, with the CGCAATC haplotype giving a specific p-value of 0.008 and odds ratio of 1.5 (95% CI 0.9-2.4). In the Nepalese cohort, SNPs in CYP1B1 and NTF4 genes showed borderline association with PACG but did not survive Bonferroni correction. Conclusions: The present data support the involvement of common variations in eNOS with PACG pathogenesis. Differences were observed in the two populations studied, and additional replication studies in other populations are necessary to confirm these associations

The author manuscript of this article is open access and is freely available online at PubMed Central, Central corneal thickness (CCT) is associated with eye conditions including keratoconus and glaucoma. We performed a meta-analysis on >20,000 individuals in European and Asian populations that identified 16 new loci associated with CCT at genome-wide significance (P < 5 × 10(-8)). We further showed that 2 CCT-associated loci, FOXO1 and FNDC3B, conferred relatively large risks for keratoconus in 2 cohorts with 874 cases and 6,085 controls (rs2721051 near FOXO1 had odds ratio (OR) = 1.62, 95% confidence interval (CI) = 1.4-1.88, P = 2.7 × 10(-10), and rs4894535 in FNDC3B had OR = 1.47, 95% CI = 1.29-1.68, P = 4.9 × 10(-9)). FNDC3B was also associated with primary open-angle glaucoma (P = 5.6 × 10(-4); tested in 3 cohorts with 2,979 cases and 7,399 controls). Further analyses implicate the collagen and extracellular matrix pathways in the regulation of CCT.

Circulating soluble intercellular adhesion molecule-1 (sICAM-1) and other novel markers have been correlated with a variety of cardiovascular outcomes, including the likelihood of future clinical cardiovascular events (1)(2)(3)(4)(5)(6)(7)(8)(9). We assessed circulating markers to explore relationships between subclinical atherosclerosis, bone density and metabolism, and fat distribution and metabolism in relation to type 2 diabetes mellitus. Serum sICAM-1, soluble vascular cell adhesion molecule-1 (sVCAM-1), sE-selectin, monocyte chemoattractant protein-1, and interleukin-6 were evaluated as markers of inflammation; adiponectin, leptin, and soluble leptin receptor as markers of adiposity; and collagen type I C-terminal propeptide, bone-specific alkaline phosphatase, osteocalcin, and N-telopeptide cross-link of type I collagen as markers of bone metabolism in a random sample of 80 participants from 53 families in the Diabetes Heart Study. The Diabetes Heart Study is a study of the cardiovascular and skeletal systems in families with siblings concordant for type 2 diabetes mellitus (10)(11) as well as unaffected family members. This study population included 42 men and 38 women, ranging in age from 39 to 81 years. Sixty-nine participants (86%) had type 2 diabetes mellitus, and 19 (24%) were African American. Serum was obtained from a morning fasted blood sample and stored at −70 °C before analysis. Commercially available assays from R&D Systems were used for measuring serum …

Congenital cataract is the most common cause of treatable visual impairment in children worldwide. Mutations in many different genes lead to congenital cataract. Recently, mutations in the receptor tyrosine kinase gene, EPHA2, have been found to cause congenital cataract in six different families. Although these findings have established EPHA2 as a causative gene, the total contribution of mutations in this gene to congenital cataract is unknown. In this study, for the first time, a population-based approach was used to investigate the frequency of disease causing mutations in the EPHA2 gene in inherited cataract cases in South-Eastern Australia. A cohort of 84 familial congenital or juvenile cataract index cases was screened for mutations in the EPHA2 gene by direct sequencing. Novel changes were assessed for segregation with the disease within the family and in unrelated controls. Microsatellite marker analysis was performed to establish any relationship between families carrying the same mutation. We report a novel congenital cataract causing mutation c.1751C>T in the EPHA2 gene and the previously reported splice mutation c.2826-9G>A in two new families. Additionally, we report a rare variant rs139787163 potentially associated with increased susceptibility to cataract. Thus mutations in EPHA2 account for 4.7% of inherited cataract cases in South-Eastern Australia. Interestingly, the identified rare variant provides a link between congenital and age-related cataract.

Refractive errors are common eye disorders of public health importance worldwide. Ocular axial length (AL) is the major determinant of refraction and thus of myopia and hyperopia. We conducted a meta-analysis of genome-wide association studies for AL, combining 12,531 Europeans and 8,216 Asians. We identified eight genome-wide significant loci for AL (RSPO1, C3orf26, LAMA2, GJD2, ZNRF3, CD55, MIP, and ALPPL2) and confirmed one previously reported AL locus (ZC3H11B). Of the nine loci, five (LAMA2, GJD2, CD55, ALPPL2, and ZC3H11B) were associated with refraction in 18 independent cohorts (n = 23,591). Differential gene expression was observed for these loci in minus-lens-induced myopia mouse experiments and human ocular tissues. Two of the AL genes, RSPO1 and ZNRF3, are involved in Wnt signaling, a pathway playing a major role in the regulation of eyeball size. This study provides evidence of shared genes between AL and refraction, but importantly also suggests that these traits may have unique pathways.

This work is licensed under a Creative Commons Attribution-Non Commercial-No Derivatives 4.0 International License (http://creativecommons.org/licenses/by-nc-nd/4.0).

Whole genome and whole exome sequencing technologies are being increasingly used in research. However, they have the potential to identify incidental findings (IF), findings not related to the indication of the test, raising questions regarding researchers' responsibilities toward the return of this information to participants. In this study we discuss the ethical considerations related to the return of IF to research participants, emphasizing that the type of the study matters and describing the current practice standards. There are currently no legal obligations for researchers to return IF to participants, but some viewpoints consider that researchers might have an ethical one to return IF of clinical validity and clinical utility and that are actionable. The reality is that most IF are complex to interpret, especially since they were not the indication of the test. The clinical utility often depends on the participants' preferences, which can be challenging to conciliate and relies on participants' understanding. In summary, in the context of a lack of clear guidance, researchers need to have a clear plan for the disclosure or nondisclosure of IF from genomic research, balancing their research goals and resources with the participants' rights and their duty not to harm.

Keratoconus is a progressive and non-inflammatory thinning of the cornea, which may result in severe visual impairment due to irregular curvature and scarring. It can occur in isolation but is often seen in association with other systemic or ocular disorders. There is a well-recognised genetic component to keratoconus, as evidenced by family and twin studies; however, the aetiology of the disease is complex with both genetic and environmental factors playing a role. Over the last decade significant progress has been made in identifying genetic risk factors for keratoconus. Multiple approaches have been taken including candidate gene studies and genome-wide studies. VSX1 remains as the best characterised keratoconus gene but only accounts for rare cases. Other candidate genes with a role to play include SOD1, other corneal dystrophy genes such as ZEB1 and TGFBI and collagen genes. Family-based studies have recently led to the identification of the MIR184 gene for keratoconus with cataract and to the DOCK9 gene in a family with isolated keratoconus. Numerous other linkages have been reported and new sequencing technologies are set to rapidly expand the number of identified keratoconus genes in these regions. Similarly, recent genome-wide association studies in case-controlled cohorts have identified common variations in and around HGF, RAB3GAP1 and LOX as candidate risk factors for keratoconus. These gene identifications are beginning to reveal the molecular aetiology of keratoconus but despite this recent progress, there remain numerous genetic risk factors to be identified for this relatively common yet complex disease.