Trends in Anti-Vascular Endothelial Growth Factor Original Medicare Part B Claims in the United States, 2014-2019

PURPOSE

To characterize trends in use of and expenditure for the intravitreal injection of anti-vascular endothelial growth factor (anti-VEGF) agents aflibercept, ranibizumab, and bevacizumab among the population enrolled in Original Medicare from 2014 to 2019.

METHODS

The Centers for Medicare and Medicaid Services Physician and Other Supplier Public Use File was used to extract Medicare Part B fee-for-service outpatient injection claims data submitted by ophthalmologists. Multivariable linear regression models were used to evaluate the association between reimbursement, ophthalmologist availability, and agent administration rate.

RESULTS

Between 2014 and 2019, 17,588,995 intravitreal injection claims were filed by 4218 US ophthalmologists. Medicare costs for anti-VEGF injections increased from 2.51 B USD in 2014 to 4.02 B USD in 2019. Increased state-level ophthalmologist availability and incremental increases in average reimbursement amounts were found to be significantly associated with a 6.8-fold variation in 2019 overall anti-VEGF injection rates across states.

CONCLUSIONS

Medicare injection rates and costs for anti-VEGF injections have both increased between 2014 and 2019, largely driven by increased aflibercept use. There is a significant association between ophthalmologist availability and anti-VEGF injection rate on the state level, suggesting access to care may contribute to the observed state-level disparities in intravitreal injection rates. Further characterization of factors contributing to the state-level variation in injection rates of individual anti-VEGF agents may help inform interventions promoting equitable access to and use of these drugs.

Open Globe Injuries From Garage Door Springs

We describe seven patients who were attempting to repair their garage door when a spring dislodged at high velocity, resulting in open globe injury. All patients were seen at Massachusetts Eye and Ear between the years 2008 and 2023. Their final visual acuities ranged from 20/125 to no light perception. Open globe injury appears to be a risk of attempts to repair a garage door by people who are inexperienced in doing so. [Ophthalmic Surg Lasers Imaging Retina 2023;54:666-669.].

Structure-based network analysis predicts mutations associated with inherited retinal disease

With continued advances in gene sequencing technologies comes the need to develop better tools to understand which mutations cause disease. Here we validate structure-based network analysis (SBNA)1,2 in well-studied human proteins and report results of using SBNA to identify critical amino acids that may cause retinal disease if subject to missense mutation. We computed SBNA scores for genes with high-quality structural data, starting with validating the method using 4 well-studied human disease-associated proteins. We then analyzed 47 inherited retinal disease (IRD) genes. We compared SBNA scores to phenotype data from the ClinVar database and found a significant difference between benign and pathogenic mutations with respect to network score. Finally, we applied this approach to 65 patients at Massachusetts Eye and Ear (MEE) who were diagnosed with IRD but for whom no genetic cause was found. Multivariable logistic regression models built using SBNA scores for IRD-associated genes successfully predicted pathogenicity of novel mutations, allowing us to identify likely causative disease variants in 37 patients with IRD from our clinic. In conclusion, SBNA can be meaningfully applied to human proteins and may help predict mutations causative of IRD.

Overlap of Genetic Loci for Central Serous Chorioretinopathy With Age-Related Macular Degeneration

Importance

Central serous chorioretinopathy (CSC) is a serous maculopathy of unknown etiology. Two of 3 previously reported CSC genetic risk loci are also associated with AMD. Improved understanding of CSC genetics may broaden our understanding of this genetic overlap and unveil mechanisms in both diseases.

Objective

To identify novel genetic risk factors for CSC and compare genetic risk factors for CSC and AMD.

Design, Setting, and Participants

Using International Classification of Diseases, Ninth (ICD-9) and Tenth (ICD-10) Revision code-based inclusion and exclusion criteria, patients with CSC and controls were identified in both the FinnGen study and the Estonian Biobank (EstBB). Also included in a meta-analysis were previously reported patients with chronic CSC and controls. Data were analyzed from March 1 to September 31, 2022.

Main Outcomes and Measures

Genome-wide association studies (GWASs) were performed in the biobank-based cohorts followed by a meta-analysis of all cohorts. The expression of genes prioritized by the polygenic priority score and nearest-gene methods were assessed in cultured choroidal endothelial cells and public ocular single-cell RNA sequencing data sets. The predictive utility of polygenic scores (PGSs) for CSC and AMD were evaluated in the FinnGen study.

Results

A total of 1176 patients with CSC and 526 787 controls (312 162 female [59.3%]) were included in this analysis: 552 patients with CSC and 343 461 controls were identified in the FinnGen study, 103 patients with CSC and 178 573 controls were identified in the EstBB, and 521 patients with chronic CSC and 3577 controls were included in a meta-analysis. Two previously reported CSC risk loci were replicated (near CFH and GATA5) and 3 novel loci were identified (near CD34/46, NOTCH4, and PREX1). The CFH and NOTCH4 loci were associated with AMD but in the opposite direction. Prioritized genes showed increased expression in cultured choroidal endothelial cells compared with other genes in the loci (median [IQR] of log 2 [counts per million], 7.3 [0.6] vs 4.7 [3.7]; P = .004) and were differentially expressed in choroidal vascular endothelial cells in single-cell RNA sequencing data (mean [SD] fold change, 2.05 [0.38] compared with other cell types; P < 7.1 × 10-20). A PGS for AMD was predictive of reduced CSC risk (odds ratio, 0.76; 95% CI, 0.70-0.83 per +1 SD in AMD-PGS; P = 7.4 × 10-10). This association may have been mediated by loci containing complement genes.

Conclusions and Relevance

In this 3-cohort genetic association study, 5 genetic risk loci for CSC were identified, highlighting a likely role for genes involved in choroidal vascular function and complement regulation. Results suggest that polygenic AMD risk was associated with reduced risk of CSC and that this genetic overlap was largely due to loci containing complement genes.

Effectiveness of a telemedicine program for triage and diagnosis of emergent ophthalmic conditions

BACKGROUND

To study the utility of a teleophthalmology program to diagnose and triage common ophthalmic complaints presenting to an ophthalmic emergency room.

METHODS

Prospective, observational study of 258 eyes of 129 patients presenting to the Massachusetts Eye and Ear Infirmary Emergency Ward (MEE EW) who completed a questionnaire to gather chief complaint (CC), history of present illness, and medical history. Anterior and posterior segment photographs were collected via iPhone 5 C camera and a Canon non-mydriatic fundus camera, respectively. Ophthalmic vital signs were collected. All information was reviewed remotely by three ophthalmologists; a diagnosis and urgency designation were recorded. The remote assessment was compared to gold standard in-person assessment.

RESULTS

The 129 recruited patients collectively contributed 220 visual complaints, of which 121 (55%) were from females with mean age 56.5 years (range 24-89). Sensitivities and specificities for telemedical triage were as follows: eye pain (n = 56; sensitivity: 0.58, CI [0.41, 0.74]; specificity: 0.91, CI [0.80, 1]), eye redness (n = 54; 0.68, CI [0.50, 0.86]; 0.93, CI [0.84, 1]), blurry vision (n = 68; 0.73, CI [0.60, 0.86]; 0.91, CI [0.80, 1]), and eyelid complaints (n = 42; 0.67, CI [0.43, 0.91]; 0.96, CI [0.89, 1]). The remote diagnostic accuracies, as stratified by CC, were eye pain (27/56; 48.21%), eye redness: (32/54; 59.26%), blurry vision: (30/68; 44.11%), eyelid (24/42; 57.14%).

CONCLUSIONS

Telemedical examination of emergent ophthalmic complaints consisting of a patient questionnaire, anterior segment and fundus photos, and ophthalmic vital signs, may be useful to reliably triage eye disease based on presenting complaint.

Bacillary Layer Detachment Associated With Endogenous Fungal Endophthalmitis

Purpose: To recognize the novel finding of a bacillary layer detachment (BALAD) secondary to endogenous fungal endophthalmitis. Methods: Chart review, literature review. Results: BALAD is a recently described condition in which the photoreceptor layer splits at the level of the inner segment myoid. We describe a case of BALAD associated with endogenous fungal endophthalmitis and subsequent development of choroidal neovascularization, although it is unclear if BALAD contributed to neovessel formation. Conclusions: BALAD is generally seen in the setting of inflammatory or infectious retinal diseases. This is the first report of BALAD secondary to endogenous fungal endophthalmitis.

SARS-CoV-2 RNA Detected in Vitreous Samples Obtained at Autopsy

Purpose:

This work aims to examine the vitreous of autopsy patients with COVID-19 for the presence of SARS-CoV-2 RNA.

Methods:

Four deceased patients with COVID-19 had an autopsy at Massachusetts General Hospital. Two control specimens were obtained from patients undergoing retinal detachment repair with negative preoperative polymerase chain reaction (PCR) testing for SARS-CoV-2 RNA. Vitreous specimens were obtained from autopsy patients with COVID-19 after povidone was placed on the ocular surface to decrease the risk of contamination of the vitreous specimen. SARS-CoV-2 RNA for gene N (nucleocapsid) was tested using reverse transcription–PCR.

Results:

SARS-CoV-2 RNA was detected in the vitreous of 2 of 4 autopsy patients who died from complications of COVID-19.

Conclusions:

SARS-CoV-2 RNA can penetrate into the vitreous of systemically infected patients, which might present risks to operating room personnel during ophthalmic surgical procedures.

Hypopyon and White Cataract Due to an Intraocular Helminth

We describe a case of a 29-year-old man with a history of intravenous drug use and vague history of eye trauma who presented with a hypopyon and white cataract in the right eye. He underwent pars plana vitrectomy and lensectomy; his anterior chamber aspirate revealed a single helminth on calcofluor stain. We suspect that his helminth infection may be secondary to unsanitary eating and drinking practices. As overall hygiene and dietary habits have improved during the years, parasitic helminth infections are relatively rare in nonendemic areas, especially in the nonpediatric population. [Ophthalmic Surg Lasers Imaging Retina. 2022;53:168-171.].

Two Cases of Cutibacterium acnes (C acnes) Endophthalmitis Manifesting With Unusual Epiretinal Deposits

This article describes two cases of delayed-onset Cutibacterium acnes (C acnes) endophthalmitis 1 month after cataract surgery manifesting with unusual epiretinal deposits. Both patients were referred for persistent inflammation after cataract surgery. After failing to respond to a vitreous tap with injection of antibiotics, the patients underwent pars plana vitrectomy and in one of the cases partial posterior capsulectomy for a posterior capsular plaque. Intraoperatively, both cases were found to have unusual multifocal epiretinal deposits. The clinical presentations described here represent a highly unique manifestation of C acnes endophthalmitis distinct from the classic anterior segment findings. [Ophthalmic Surg Lasers Imaging Retina. 2022;53:164-167.].

Aflibercept for Retinopathy of Prematurity: A Systematic Review and Meta-Analysis

BACKGROUND AND OBJECTIVE

To determine the effectiveness of aflibercept in retinopathy of prematurity (ROP).

PATIENTS AND METHODS

We performed a systematic review and meta-analysis of proportions from the literature in PubMed and Cochrane Library using search terms related to the use of aflibercept in ROP. Studies in non-preterm infants or that did not use aflibercept as the initial treatment were excluded. Risk of bias was assessed by the ROBINS-I (Risk Of Bias in Non-randomized Studies of Interventions) tool.

RESULTS

We identified six case series. Collectively, 218 eyes were treated with aflibercept for ROP. We found an average 97% (95% confidence interval [CI], 93% to 99%) regression rate with aflibercept and an average 16% (95% CI, 5% to 41%) recurrence rate. With the exception of one outlier study, these numbers are similar to previous reports using anti-vascular endothelial growth factor (VEGF) agents in ROP.

CONCLUSIONS

Aflibercept holds promise for use in ROP and has been demonstrated to be efficacious in six case series. Randomized, controlled clinical trials appear warranted to compare aflibercept with other anti-VEGF agents. [Ophthalmic Surg Lasers Imaging. 2021;52:673-681.].

HLA class-I-peptide stability mediates CD8+ T cell immunodominance hierarchies and facilitates HLA-associated immune control of HIV

Defining factors that govern CD8⁺ T cell immunodominance is critical for the rational design of vaccines for viral pathogens. Here, we assess the contribution of human leukocyte antigen (HLA) class-I-peptide stability for 186 optimal HIV epitopes across 18 HLA alleles using transporter associated with antigen processing (TAP)-deficient mono-allelic HLA-expressing cell lines. We find that immunodominant HIV epitopes increase surface stabilization of HLA class-I molecules in comparison to subdominant epitopes. HLA class-I-peptide stability is also strongly correlated with overall immunodominance hierarchies, particularly for epitopes from high-abundance proteins (e.g., Gag). Moreover, HLA alleles associated with HIV protection are preferentially stabilized by epitopes derived from topologically important viral regions at a greater frequency than neutral and risk alleles. These findings indicate that relative stabilization of HLA class-I is a key factor for CD8⁺ T cell epitope immunodominance hierarchies, with implications for HIV control and the design of T-cell-based vaccines.

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TAP-deficient HLA-expressing cells provide rapid assessment of HLA-peptide stability

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Immunodominant HIV CD8⁺ T cell epitopes are superior stabilizers of HLA molecules

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HLA class-I-peptide stability correlates with overall immunodominance hierarchies

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Protective HLA alleles are preferentially stabilized by highly networked epitopes

Structure-guided T cell vaccine design for SARS-CoV-2 variants and sarbecoviruses

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants that escape convalescent and vaccine-induced antibody responses has renewed focus on the development of broadly protective T-cell-based vaccines. Here, we apply structure-based network analysis and assessments of HLA class I peptide stability to define mutationally constrained CD8⁺ T cell epitopes across the SARS-CoV-2 proteome. Highly networked residues are conserved temporally among circulating variants and sarbecoviruses and disproportionately impair spike pseudotyped lentivirus infectivity when mutated. Evaluation of HLA class I stabilizing activity for 18 globally prevalent alleles identifies CD8⁺ T cell epitopes within highly networked regions with limited mutational frequencies in circulating SARS-CoV-2 variants and deep-sequenced primary isolates. Moreover, these epitopes elicit demonstrable CD8⁺ T cell reactivity in convalescent individuals but reduced recognition in recipients of mRNA-based vaccines. These data thereby elucidate key mutationally constrained regions and immunogenic epitopes in the SARS-CoV-2 proteome for a global T-cell-based vaccine against emerging variants and SARS-like coronaviruses.

Factors Associated With Increased Risk of Serious Ocular Injury in the Setting of Orbital Fracture

Importance

Orbital fractures are common in ocular trauma, and there is a need to develop predictive tools to estimate risk of concurrent ocular injury.

Objective

To identify clinical and radiographic features that are associated with increased risk of substantial ocular injury in the setting of orbital fracture.

Design, Setting, and Participants

Retrospective consecutive case series of patients who sustained orbital fractures between 2012 and 2018. Examinations were done at 1 of 2 level 1 trauma centers in the emergency or inpatient setting. A total of 430 consecutive patients (500 eyes) between 2012 and 2017 met inclusion criteria for the training sample. After building a predictive model, 88 additional consecutive patients (97 eyes) between 2017 and 2018 who met inclusion criteria were collected as a test sample.

Main Outcomes and Measures

The primary outcome measure was substantial ocular injury distinct from orbital fracture.

Results

The mean age of our patient population was 53.5 years (range, 16-100 years). The overall rate of substantial ocular injury was 20.4%, and the rate of injury requiring immediate ophthalmic attention was 14.4%. Five variables were found to be associated with increased risk of substantial ocular injury: blunt trauma with a foreign object (odds ratio [OR], 19.4; 95% CI, 6.3-64.1; P < .001), inability to count fingers (OR, 10.1; 95% CI, 2.8-41.1; P = .002), roof fracture (OR, 9.1; 95% CI, 2.8-30.0; P = .002), diplopia on primary gaze (OR, 6.7; 95% CI, 1.7-25.1; P = .003), and conjunctival hemorrhage or chemosis (OR, 4.2; 95% CI, 2.2-8.5; P < .001). The results were translated into a bedside tool that was tested in an independent group of eyes (n = 97) and found to be associated with substantial ocular injury with a 95% sensitivity (95% CI, 77.2-99.9), 40% specificity (95% CI, 28.9-52.0), 31.8% positive predictive value (95% CI, 27.5-36.5), and 96.8% negative predictive value (95% CI, 81.3-99.5).

Conclusions and Relevance

A minority of patients with an orbital fracture had a substantial ocular injury. Certain radiographic and clinical findings were associated with substantial ocular injury. Testing of the algorithm in prospective longitudinal settings appears warranted.

Site of Origin of the Ophthalmic Artery Influences the Risk for Retinal Versus Cerebral Embolic Events

BACKGROUND

Embolic events leading to retinal ischemia or cerebral ischemia share common risk factors; however, it has been well documented that the rate of concurrent cerebral infarction is higher in patients with a history of transient ischemic attack (TIA) than in those with monocular vision loss (MVL) due to retinal ischemia. Despite the fact that emboli to the ophthalmic artery (OA) and middle cerebral artery share the internal carotid artery (ICA) as a common origin or transit for emboli, the asymmetry in their final destination has not been fully explained. We hypothesize that the anatomic location of the OA takeoff from the ICA may contribute to the differential flow of small emboli to the retinal circulation vs the cerebral circulation.

METHODS

We report a retrospective, comparative, case-control study on 28 patients with retinal ischemia and 26 patients with TIA or cerebral infarction caused by embolic events. All subjects underwent either computed tomography angiography or MRA. The location of the ipsilateral OA origin off the ICA was then graded in a blinded fashion and compared between cohorts. Vascular risk factors were collected for all patients, including age, sex, hypertension, hyperlipidemia, arrhythmia, diabetes, coronary artery disease, and smoking.

RESULTS

We find that in patients with retinal ischemia of embolic etiology, the ipsilateral OA takeoff from the ICA is more proximal than in patients with cerebral infarcts or TIA (P = 0.0002). We found no statistically significant differences in demographic, vascular, or systemic risk factors.

CONCLUSIONS

We find that the mean anatomical location of the OA takeoff from the ICA is significantly more proximal in patients with MVL due to retinal ischemia compared with patients with TIA or cerebral ischemia. This finding contributes significantly to our understanding of a long observed but poorly understood phenomenon that patients with MVL are less likely to have concurrent cerebral ischemia than are patients with TIA.

Single-cell RNA sequencing: An overview for the ophthalmologist

Understanding the molecular composition of pathogenic tissues is a critical step in understanding the pathophysiology of disease and designing therapeutics. First described in 2009, single cell RNA sequencing (scRNAseq) is a methodology whereby thousands of cells are simultaneously isolated into individual micro-environments that can be altered experimentally and the genome-wide RNA expression of each cell is captured. It has undergone significant technological improvement over the last decade and gained tremendous popularity. scRNAseq is an improvement over prior pooled RNA analyses which cannot identify the cellular composition and heterogeneity of a tissue of interest. This new approach offers new opportunity for new discovery, as tissue samples can now be sub-categorized into groups of cell types based on genome-wide gene expression in an unbiased fashion. As ophthalmologists, we are uniquely positioned to obtain pathologic samples from the eye for further study. ScRNAseq has already been applied in ophthalmology to characterize retinal tissue, and it may offer the key to understanding various pathological processes in the future.

Topical delivery of a small molecule RUNX1 transcription factor inhibitor for the treatment of proliferative vitreoretinopathy

Proliferative vitreoretinopathy (PVR) is the leading cause of retinal detachment surgery failure. Despite significant advances in vitreoretinal surgery, it still remains without an effective prophylactic or therapeutic medical treatment. After ocular injury or retinal detachment, misplaced retinal cells undergo epithelial to mesenchymal transition (EMT) to form contractile membranes within the eye. We identified Runt-related transcription factor 1 (RUNX1) as a gene highly expressed in surgically-removed human PVR specimens. RUNX1 upregulation was a hallmark of EMT in primary cultures derived from human PVR membranes (C-PVR). The inhibition of RUNX1 reduced proliferation of human C-PVR cells in vitro, and curbed growth of freshly isolated human PVR membranes in an explant assay. We formulated Ro5-3335, a lipophilic small molecule RUNX1 inhibitor, into a nanoemulsion that when administered topically curbed the progression of disease in a novel rabbit model of mild PVR developed using C-PVR cells. Mass spectrometry analysis detected 2.67 ng/mL of Ro5-3335 within the vitreous cavity after treatment. This work shows a critical role for RUNX1 in PVR and supports the feasibility of targeting RUNX1 within the eye for the treatment of an EMT-mediated condition using a topical ophthalmic agent.

Traumatic Retinal Detachment in Patients with Self-Injurious Behavior: An International Multicenter Study

PURPOSE

To describe the clinical characteristics, surgical outcomes, and management recommendations in patients with traumatic rhegmatogenous retinal detachment (RRD) resulting from self-injurious behavior (SIB).

DESIGN

International, multicenter, retrospective, interventional case series.

PARTICIPANTS

Patients with SIB from 23 centers with RRD in at least 1 eye.

METHODS

Clinical histories, preoperative assessment, surgical details, postoperative management, behavioral intervention, and follow-up examination findings were reviewed.

MAIN OUTCOME MEASURES

The rate of single-surgery anatomic success (SSAS) was the primary outcome. Other outcomes included new RRD in formerly attached eyes, final retinal reattachment, and final visual acuity.

RESULTS

One hundred seven eyes with RRDs were included from 78 patients. Fifty-four percent of patients had bilateral RRD or phthisis bulbi in the fellow eye at final follow-up. The most common systemic diagnoses were autism spectrum disorder (35.9%) and trisomy 21 (21.8%) and the most common behavior was face hitting (74.4%). The average follow-up time was 3.3 ± 2.8 years, and surgical outcomes for operable eyes were restricted to patients with at least 3 months of follow-up (81 eyes). Primary initial surgeries were vitrectomy alone (33.3%), primary scleral buckle (SB; 26.9%), and vitrectomy with SB (39.7%), and 5 prophylactic SBs were placed. Twenty-three eyes (21.5%) with RRDs were inoperable. The SSAS was 23.1% without tamponade (37.2% if including silicone oil), and final reattachment was attained in 80% (36.3% without silicone oil tamponade). Funnel-configured RRD (P = 0.006) and the presence of grade C proliferative vitreoretinopathy (P = 0.002) correlated with re-detachment. The use of an SB predicted the final attachment rate during the initial surgery (P = 0.005) or at any surgery (P = 0.008. These associations held if restricting to 64 patients with ≥12 months followup. Anatomic reattachment correlated with better visual acuity (P < 0.001).

CONCLUSIONS

RRD resulting from SIB poses therapeutic challenges because of limited patient cooperation, bilateral involvement, chronicity, and ongoing trauma in vulnerable and neglected patients. The surgical success rates were some of the lowest in the modern retinal detachment literature. The use of an SB may result in better outcomes, and visual function can be restored in some patients.

Structural topology defines protective CD8+ T cell epitopes in the HIV proteome

Mutationally constrained epitopes of variable pathogens represent promising targets for vaccine design but are not reliably identified by sequence conservation. In this study, we employed structure-based network analysis, which applies network theory to HIV protein structure data to quantitate the topological importance of individual amino acid residues. Mutation of residues at important network positions disproportionately impaired viral replication and occurred with high frequency in epitopes presented by protective human leukocyte antigen (HLA) class I alleles. Moreover, CD8⁺ T cell targeting of highly networked epitopes distinguished individuals who naturally control HIV, even in the absence of protective HLA alleles. This approach thereby provides a mechanistic basis for immune control and a means to identify CD8⁺ T cell epitopes of topological importance for rational immunogen design, including a T cell-based HIV vaccine.

Multiethnic Genome-Wide Association Study of Diabetic Retinopathy Using Liability Threshold Modeling of Duration of Diabetes and Glycemic Control

To identify genetic variants associated with diabetic retinopathy (DR), we performed a large multiethnic genome-wide association study. Discovery included eight European cohorts (n = 3,246) and seven African American cohorts (n = 2,611). We meta-analyzed across cohorts using inverse-variance weighting, with and without liability threshold modeling of glycemic control and duration of diabetes. Variants with a P value <1 × 10-5 were investigated in replication cohorts that included 18,545 European, 16,453 Asian, and 2,710 Hispanic subjects. After correction for multiple testing, the C allele of rs142293996 in an intron of nuclear VCP-like (NVL) was associated with DR in European discovery cohorts (P = 2.1 × 10-9), but did not reach genome-wide significance after meta-analysis with replication cohorts. We applied the Disease Association Protein-Protein Link Evaluator (DAPPLE) to our discovery results to test for evidence of risk being spread across underlying molecular pathways. One protein-protein interaction network built from genes in regions associated with proliferative DR was found to have significant connectivity (P = 0.0009) and corroborated with gene set enrichment analyses. These findings suggest that genetic variation in NVL, as well as variation within a protein-protein interaction network that includes genes implicated in inflammation, may influence risk for DR.

Bilateral Immediate Sequential Vitrectomy and Lensectomy for Bilateral Lens Dislocation in Severe Neonatal Marfan Syndrome

A newborn with severe neonatal Marfan syndrome (NMS), characterized by aortic root dilation, mitral and tricuspid valve regurgitation, diaphragmatic eventration with respiratory distress, intestinal malrotation, and various skeletal abnormalities, developed bilateral pupillary block from luxated crystalline lenses. He underwent bilateral immediate sequential vitrectomy and lensectomy to prevent further episodes of pupillary block. Bilateral surgery was performed due to the extremely high anesthesia risk. NMS is a rare and severe form of the connective tissue disease that can present with numerous systemic and ocular findings. Measures to decrease anesthesia risk are recommended, including the consideration of bilateral surgery. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:e151-e153.].

Anterior–Posterior Persistent Fetal Vasculature With Multiple Stalks: Persistent Vasa Hyaloidea Propria

An 8-week-old boy referred for an abnormal pupil was found to have an atypical presentation of persistent fetal vasculature (PFV) with multiple vascular stalks. Examination under anesthesia with fluorescein angiography (FA) revealed 2 perfused persistent hyaloid vessels, one extending from the optic disc and another from the inferonasal retina. These vessels meet anteriorly to form a vascular network at the lens, which is the remnant of the tunica vasculosa lentis. Although the posterior portion of PFV typically presents as a single stalk attached at the optic disc, this case features an atypical presentation of 2 distinct vascular stalks, which may expand our understanding of ocular development and pathogenesis of PFV. We hypothesize that the aberrant additional stalk may represent failure of the vasa hyaloidea propria (tributaries of the hyaloid artery) to regress.

Survey of variation in human transcription factors reveals prevalent DNA binding changes

Sequencing of exomes and genomes has revealed abundant genetic variation affecting the coding sequences of human transcription factors (TFs), but the consequences of such variation remain largely unexplored. We developed a computational, structure-based approach to evaluate TF variants for their impact on DNA binding activity and used universal protein-binding microarrays to assay sequence-specific DNA binding activity across 41 reference and 117 variant alleles found in individuals of diverse ancestries and families with Mendelian diseases. We found 77 variants in 28 genes that affect DNA binding affinity or specificity and identified thousands of rare alleles likely to alter the DNA binding activity of human sequence-specific TFs. Our results suggest that most individuals have unique repertoires of TF DNA binding activities, which may contribute to phenotypic variation.

Genetic association study of QT interval highlights role for calcium signaling pathways in myocardial repolarization

The QT interval, an electrocardiographic measure reflecting myocardial repolarization, is a heritable trait. QT prolongation is a risk factor for ventricular arrhythmias and sudden cardiac death (SCD) and could indicate the presence of the potentially lethal Mendelian Long QT Syndrome (LQTS). Using a genome-wide association and replication study in up to 100,000 individuals we identified 35 common variant QT interval loci, that collectively explain ∼8-10% of QT variation and highlight the importance of calcium regulation in myocardial repolarization. Rare variant analysis of 6 novel QT loci in 298 unrelated LQTS probands identified coding variants not found in controls but of uncertain causality and therefore requiring validation. Several newly identified loci encode for proteins that physically interact with other recognized repolarization proteins. Our integration of common variant association, expression and orthogonal protein-protein interaction screens provides new insights into cardiac electrophysiology and identifies novel candidate genes for ventricular arrhythmias, LQTS,and SCD.

Genome-wide trans-ancestry meta-analysis provides insight into the genetic architecture of type 2 diabetes susceptibility

To further understanding of the genetic basis of type 2 diabetes (T2D) susceptibility, we aggregated published meta-analyses of genome-wide association studies (GWAS) including 26,488 cases and 83,964 controls of European, East Asian, South Asian, and Mexican and Mexican American ancestry. We observed significant excess in directional consistency of T2D risk alleles across ancestry groups, even at SNPs demonstrating only weak evidence of association. By following up the strongest signals of association from the trans-ethnic meta-analysis in an additional 21,491 cases and 55,647 controls of European ancestry, we identified seven novel T2D susceptibility loci. Furthermore, we observed considerable improvements in fine-mapping resolution of common variant association signals at several T2D susceptibility loci. These observations highlight the benefits of trans-ethnic GWAS for the discovery and characterisation of complex trait loci, and emphasize an exciting opportunity to extend insight into the genetic architecture and pathogenesis of human diseases across populations of diverse ancestry.

Human genetics in rheumatoid arthritis guides a high-throughput drug screen of the CD40 signaling pathway

Although genetic and non-genetic studies in mouse and human implicate the CD40 pathway in rheumatoid arthritis (RA), there are no approved drugs that inhibit CD40 signaling for clinical care in RA or any other disease. Here, we sought to understand the biological consequences of a CD40 risk variant in RA discovered by a previous genome-wide association study (GWAS) and to perform a high-throughput drug screen for modulators of CD40 signaling based on human genetic findings. First, we fine-map the CD40 risk locus in 7,222 seropositive RA patients and 15,870 controls, together with deep sequencing of CD40 coding exons in 500 RA cases and 650 controls, to identify a single SNP that explains the entire signal of association (rs4810485, P = 1.4×10⁻⁹). Second, we demonstrate that subjects homozygous for the RA risk allele have ∼33% more CD40 on the surface of primary human CD19+ B lymphocytes than subjects homozygous for the non-risk allele (P = 10⁻⁹), a finding corroborated by expression quantitative trait loci (eQTL) analysis in peripheral blood mononuclear cells from 1,469 healthy control individuals. Third, we use retroviral shRNA infection to perturb the amount of CD40 on the surface of a human B lymphocyte cell line (BL2) and observe a direct correlation between amount of CD40 protein and phosphorylation of RelA (p65), a subunit of the NF-κB transcription factor. Finally, we develop a high-throughput NF-κB luciferase reporter assay in BL2 cells activated with trimerized CD40 ligand (tCD40L) and conduct an HTS of 1,982 chemical compounds and FDA–approved drugs. After a series of counter-screens and testing in primary human CD19+ B cells, we identify 2 novel chemical inhibitors not previously implicated in inflammation or CD40-mediated NF-κB signaling. Our study demonstrates proof-of-concept that human genetics can be used to guide the development of phenotype-based, high-throughput small-molecule screens to identify potential novel therapies in complex traits such as RA.

A current challenge in human genetics is to follow-up “hits” from genome-wide association studies (GWAS) to guide drug discovery for complex traits. Previously, we identified a common variant in the CD40 locus as associated with risk of rheumatoid arthritis (RA). Here, we fine-map the CD40 signal of association through a combination of dense genotyping and exonic sequencing in large patient collections. Further, we demonstrate that the RA risk allele is a gain-of-function allele that increases the amount of CD40 on the surface of primary human B lymphocyte cells from healthy control individuals. Based on these observations, we develop a high-throughput assay to recapitulate the biology of the RA risk allele in a system suitable for a small molecule drug screen. After a series of primary screens and counter screens, we identify small molecules that inhibit CD40-mediated NF-kB signaling in human B cells. While this is only the first step towards a more comprehensive effort to identify CD40-specific inhibitors that may be used to treat RA, our study demonstrates a successful strategy to progress from a GWAS to a drug screen for complex traits such as RA.

Identification of heart rate-associated loci and their effects on cardiac conduction and rhythm disorders

Elevated resting heart rate is associated with greater risk of cardiovascular disease and mortality. In a 2-stage meta-analysis of genome-wide association studies in up to 181,171 individuals, we identified 14 new loci associated with heart rate and confirmed associations with all 7 previously established loci. Experimental downregulation of gene expression in Drosophila melanogaster and Danio rerio identified 20 genes at 11 loci that are relevant for heart rate regulation and highlight a role for genes involved in signal transmission, embryonic cardiac development and the pathophysiology of dilated cardiomyopathy, congenital heart failure and/or sudden cardiac death. In addition, genetic susceptibility to increased heart rate is associated with altered cardiac conduction and reduced risk of sick sinus syndrome, and both heart rate-increasing and heart rate-decreasing variants associate with risk of atrial fibrillation. Our findings provide fresh insights into the mechanisms regulating heart rate and identify new therapeutic targets.

Large-scale association analysis provides insights into the genetic architecture and pathophysiology of type 2 diabetes

To extend understanding of the genetic architecture and molecular basis of type 2 diabetes (T2D), we conducted a meta-analysis of genetic variants on the Metabochip, including 34,840 cases and 114,981 controls, overwhelmingly of European descent. We identified ten previously unreported T2D susceptibility loci, including two showing sex-differentiated association. Genome-wide analyses of these data are consistent with a long tail of additional common variant loci explaining much of the variation in susceptibility to T2D. Exploration of the enlarged set of susceptibility loci implicates several processes, including CREBBP-related transcription, adipocytokine signaling and cell cycle regulation, in diabetes pathogenesis.

Proteins encoded in genomic regions associated with immune-mediated disease physically interact and suggest underlying biology

Genome-wide association studies (GWAS) have defined over 150 genomic regions unequivocally containing variation predisposing to immune-mediated disease. Inferring disease biology from these observations, however, hinges on our ability to discover the molecular processes being perturbed by these risk variants. It has previously been observed that different genes harboring causal mutations for the same Mendelian disease often physically interact. We sought to evaluate the degree to which this is true of genes within strongly associated loci in complex disease. Using sets of loci defined in rheumatoid arthritis (RA) and Crohn's disease (CD) GWAS, we build protein-protein interaction (PPI) networks for genes within associated loci and find abundant physical interactions between protein products of associated genes. We apply multiple permutation approaches to show that these networks are more densely connected than chance expectation. To confirm biological relevance, we show that the components of the networks tend to be expressed in similar tissues relevant to the phenotypes in question, suggesting the network indicates common underlying processes perturbed by risk loci. Furthermore, we show that the RA and CD networks have predictive power by demonstrating that proteins in these networks, not encoded in the confirmed list of disease associated loci, are significantly enriched for association to the phenotypes in question in extended GWAS analysis. Finally, we test our method in 3 non-immune traits to assess its applicability to complex traits in general. We find that genes in loci associated to height and lipid levels assemble into significantly connected networks but did not detect excess connectivity among Type 2 Diabetes (T2D) loci beyond chance. Taken together, our results constitute evidence that, for many of the complex diseases studied here, common genetic associations implicate regions encoding proteins that physically interact in a preferential manner, in line with observations in Mendelian disease.