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Purpose The phase 2 BOULEVARD trial compared safety and efficacy of faricimab, a novel bispecific antibody targeting angiopoietin-2 and vascular endothelial growth factor-A (VEGF-A), with ranibizumab in patients with diabetic macular edema (DME). Design The BOULEVARD trial ( ClinicalTrials.gov identifier, NCT02699450 ) was a prospective, randomized, active comparator-controlled, double-masked, multicenter, phase 2 study conducted at 59 sites in the United States. Participants The trial enrolled patients 18 years of age or older with center-involving DME, best-corrected visual acuity (BCVA) of 73 to 24 Early Treatment Diabetic Retinopathy Study (ETDRS) letters, and central subfield thickness (CST) of 325 μm or more. Methods Anti-VEGF treatment-naive patients were randomized 1:1:1 to intravitreal 6.0 mg faricimab, 1.5 mg faricimab, or 0.3 mg ranibizumab, and patients previously treated with anti-VEGF were randomized 1:1 to 6.0 mg faricimab or 0.3 mg ranibizumab. Patients were dosed monthly for 20 weeks, followed by an observation period up to week 36 to assess durability. Main Outcome Measures The prespecified primary outcome measure was mean change in BCVA from baseline at week 24 for faricimab versus ranibizumab in treatment-naive patients. Key secondary and exploratory outcome measures included CST, Diabetic Retinopathy Severity Scale (DRSS) score, and durability as assessed by time to re-treatment. Results The trial enrolled 229 patients (168 treatment-naive and 61 previously treated with anti-VEGF). In treatment-naive patients, 6.0 mg faricimab, 1.5 mg faricimab, and 0.3 mg ranibizumab resulted in mean improvements of 13.9, 11.7, and 10.3 ETDRS letters from baseline, respectively. The 6.0-mg faricimab dose demonstrated a statistically significant gain of 3.6 letters over ranibizumab (P = 0.03). In both patient populations, faricimab resulted in dose-dependent reductions in CST, improvements in DRSS score, and longer time to re-treatment during the observation period compared with ranibizumab. Faricimab showed no new or unexpected safety signals. Conclusions The BOULEVARD trial met its primary end point; faricimab demonstrated statistically superior visual acuity gains versus ranibizumab at week 24 in treatment-naive patients. Central subfield thickness reduction, DRSS score improvement, and extended durability outcomes support the primary outcome. These findings suggest the benefit of simultaneous inhibition of angiopoietin-2 and VEGF-A with faricimab for patients with DME.

We propose a hybrid sequential prediction model called “Deep Sequence”, integrating radiomics-engineered imaging features, demographic, and visual factors, with a recursive neural network (RNN) model in the same platform to predict the risk of exudation within a future time-frame in non-exudative AMD eyes. The proposed model provides scores associated with risk of exudation in the short term (within 3 months) and long term (within 21 months), handling challenges related to variability of OCT scan characteristics and the size of the training cohort. We used a retrospective clinical trial dataset that includes 671 AMD fellow eyes with 13,954 observations before any signs of exudation for training and validation in a tenfold cross validation setting. Deep Sequence achieved high performance for the prediction of exudation within 3 months (0.96 ± 0.02 AUCROC) and within 21 months (0.97 ± 0.02 AUCROC) on cross-validation. Training the proposed model on this clinical trial dataset and testing it on an external real-world clinical dataset showed high performance for the prediction within 3-months (0.82 AUCROC) but a clear decrease in performance for the prediction within 21-months (0.68 AUCROC). While performance differences at longer time intervals may be derived from dataset differences, we believe that the high performance and generalizability achieved in short-term predictions may have a high clinical impact allowing for optimal patient follow-up, adding the possibility of more frequent, detailed screening and tailored treatments for those patients with imminent risk of exudation.

Artificial intelligence has recently made a disruptive impact in medical imaging by successfully automatizing expert-level diagnostic tasks. However, replicating human-made decisions may inherently be biased by the fallible and dogmatic nature of human experts, in addition to requiring prohibitive amounts of training data. In this paper, we introduce an unsupervised deep learning architecture particularly designed for OCT representations for unbiased, purely data-driven biomarker discovery. We developed artificial intelligence technology that provides biomarker candidates without any restricting input or domain knowledge beyond raw images. Analyzing 54,900 retinal optical coherence tomography (OCT) volume scans of 1094 patients with age-related macular degeneration, we generated a vocabulary of 20 local and global markers capturing characteristic retinal patterns. The resulting markers were validated by linking them with clinical outcomes (visual acuity, lesion activity and retinal morphology) using correlation and machine learning regression. The newly identified features correlated well with specific biomarkers traditionally used in clinical practice (r up to 0.73), and outperformed them in correlating with visual acuity ($$\hbox {R}^{2} = 0.46$$R2=0.46 compared to $$\hbox {R}^{2} = 0.29$$R2=0.29 for conventional markers), despite representing an enormous compression of OCT imaging data (67 million voxels to 20 features). In addition, our method also discovered hitherto unknown, clinically relevant biomarker candidates. The presented deep learning approach identified known as well as novel medical imaging biomarkers without any prior domain knowledge. Similar approaches may be worthwhile across other medical imaging fields.

Purpose To characterize retinal morphology differences among different types of choroidal neovascularization and visual function changes at the onset of exudative age-related macular degeneration. Methods In a post hoc analysis of a prospective clinical study, 1,097 fellow eyes from subjects with choroidal neovascularization in the study eye enrolled in the HARBOR trial were evaluated. The onset of exudation was diagnosed on monthly optical coherence tomography by two masked graders. At conversion as well as 1 month earlier, pigment epithelial detachment, intraretinal cystoid fluid, subretinal fluid, subretinal hyperreflective material, as well as ellipsoid zone and external limiting membrane loss were quantitatively analyzed. Hyperreflective foci, retinal pigment epithelial defects, haze and vitreoretinal interface status were evaluated qualitatively. Main outcome measures included visual acuity and rates of morphologic features at conversion and 1 month earlier. Results New-onset exudation was detected in 92 eyes. One month before conversion, hyperreflective foci, pigment epithelial detachment, retinal pigment epithelial defects, and haze were present in the majority of eyes. At the onset of exudation, the volumes of intraretinal cystoid fluid, subretinal fluid, subretinal hyperreflective material and pigment epithelial detachment, and the areas of external limiting membrane and ellipsoid zone loss significantly increased. The mean vision loss was -2.2 letters. Pathognomonic patterns of the different choroidal neovascularization types were already apparent 1 month before conversion. Conclusion Characteristic choroidal neovascularization-associated morphological changes are preceding disease conversion, while vision loss at the onset of exudation is minimal. Individual lesion types are related to specific changes in optical coherence tomography morphology already before the time of conversion. Our findings may help to elucidate the pathophysiology of neovascular age-related macular degeneration and support the diagnosis of imminent disease conversion.

Importance Faricimab neutralizes angiopoietin-2 and vascular endothelial growth factor A via both simultaneous and independent binding. Objective To evaluate extended dosing with faricimab, the first bispecific antibody designed for intraocular use, in patients with neovascular age-related macular degeneration. Design, setting, and participants This phase 2 randomized clinical trial was a 52-week multicenter, active comparator-controlled, parallel-group study. Study participants were enrolled in 25 sites in the US from January and March 2017 with treatment-naive choroidal neovascularization secondary to neovascular age-related macular degeneration and best-corrected visual acuity (BCVA) Early Treatment Diabetic Retinopathy Study letter score of 73 (approximate Snellen equivalent, 20/40) to 24 (approximate Snellen equivalent, 20/320). Analysis began January 2017 and ended March 2018. Interventions Participants were randomized 1:2:2 to receive intravitreal ranibizumab, 0.5 mg, every 4 weeks or faricimab, 6.0 mg, every 12 or 16 weeks. Participants in the faricimab arms initially received 4 monthly injections of faricimab. No rescue injections were allowed. Participants randomized to dosing every 16 weeks were assessed for disease activity at week 24 using prespecified criteria. Those with no active disease continued dosing every 16 weeks through trial end; participants with disease activity continued received dosing every 12 weeks. Main outcomes and measures Mean change in BCVA from baseline at week 40. Results Of 76 participants enrolled (mean [SD] age, 78.5 [8.5] years; age range, 56-94 years; 41 women [58%]; 69 white [97%]), 16 (21.0%) were randomized to ranibizumab every 4 weeks, 29 (38.2%) to faricimab every 12 weeks, and 31 (40.8%) to faricimab every 16 weeks. At week 24, 12 weeks after their last initiation injection, 65% (36 of 55) of all faricimab-treated participants had no disease activity. At week 40, adjusted mean BCVA gains from baseline (Early Treatment Diabetic Retinopathy Study letters) were +11.4 (80% CI, 7.8-15.0), +9.3 (80% CI, 6.4-12.3), and +12.5 (80% CI, 9.9-15.1) for the ranibizumab every 4 weeks, faricimab every 12 weeks, and faricimab every 16 weeks arms, respectively. Participants received a mean (SD) total of 12.9 (0.25), 6.7 (0.91), and 6.2 (0.93) injections, for the ranibizumab every 4 weeks, faricimab every 12 weeks, and faricimab every 16 weeks arms, respectively, through week 52. The secondary BCVA and anatomical imaging end points supported the primary end point and were comparable with ranibizumab every 4 weeks. No new or unexpected safety signals were identified. Conclusions and relevance At week 52, faricimab dosing every 16 weeks and every 12 weeks resulted in maintenance of initial vision and anatomic improvements comparable with monthly ranibizumab. These results suggest a role for simultaneous neutralization of angiopoietin-2 and vascular endothelial growth factor A in providing sustained efficacy through extended durability, warranting further investigation. Trial registration ClinicalTrials.gov Identifier: NCT03038880.

Purpose While millions of individuals show early age-related macular degeneration (AMD) signs, yet have excellent vision, the risk of progression to advanced AMD with legal blindness is highly variable. We suggest means of artificial intelligence to individually predict AMD progression. Methods In eyes with intermediate AMD, progression to the neovascular type with choroidal neovascularization (CNV) or the dry type with geographic atrophy (GA) was diagnosed based on standardized monthly optical coherence tomography (OCT) images by independent graders. We obtained automated volumetric segmentation of outer neurosensory layers and retinal pigment epithelium, drusen, and hyperreflective foci by spectral domain-OCT image analysis. Using imaging, demographic, and genetic input features, we developed and validated a machine learning-based predictive model assessing the risk of conversion to advanced AMD. Results Of a total of 495 eyes, 159 eyes (32%) had converted to advanced AMD within 2 years, 114 eyes progressed to CNV, and 45 to GA. Our predictive model differentiated converting versus nonconverting eyes with a performance of 0.68 and 0.80 for CNV and GA, respectively. The most critical quantitative features for progression were outer retinal thickness, hyperreflective foci, and drusen area. The features for conversion showed pathognomonic patterns that were distinctly different for the neovascular and the atrophic pathways. Predictive hallmarks for CNV were mostly drusen-centric, while GA markers were associated with neurosensory retina and age. Conclusions Artificial intelligence with automated analysis of imaging biomarkers allows personalized prediction of AMD progression. Moreover, pathways of progression may be specific in respect to the neovascular/atrophic type.

Purpose To evaluate the potential of machine learning to predict best-corrected visual acuity (BCVA) outcomes from structural and functional assessments during the initiation phase in patients receiving standardized ranibizumab therapy for neovascular age-related macular degeneration (AMD). Design Post hoc analysis of a randomized, prospective clinical trial. Participants Data of 614 evaluable patients receiving intravitreal ranibizumab monthly or pro re nata according to protocol-specified criteria in the HARBOR trial. Methods Monthly spectral-domain (SD) OCT volume scans were processed by validated, fully automated computational image analysis. This system performs spatially resolved 3-dimensional segmentation of retinal layers, intraretinal cystoid fluid (IRF), subretinal fluid (SRF), and pigment epithelial detachments (PED). The extracted quantitative OCT biomarkers and BCVA measurements at baseline and months 1, 2, and 3 were used to predict BCVA at 12 months using random forest machine learning. This approach was also used to correlate OCT morphology to BCVA at baseline (structure–function correlation). Main Outcome Measures Accuracy (R 2 ) of the prediction models; ranking of input variables. Results Computational image analysis enabled fully automated quantitative characterization of neovascular lesions in a large-scale clinical SD-OCT data set. At baseline, OCT features and BCVA were correlated with R 2 = 0.21. The most relevant biomarker for BCVA was the horizontal extension of IRF in the foveal region, whereas SRF and PED ranked low. In predicting functional outcomes, the model's accuracy increased in a linear fashion with each month. If only the baseline visit was considered, the accuracy was R 2 = 0.34. At month 3, final visual acuity outcomes could be predicted with an accuracy of R 2 = 0.70. The strongest predictive factor for functional outcomes at 1 year was consistently the individual BCVA level during the initiation phase. Conclusions In this large-scale study based on a wide spectrum of morphologic and functional features, baseline BCVA correlated modestly with baseline SD-OCT, whereas functional outcomes were determined by BCVA levels during the initiation phase with a minor influence of fluid-related features. This finding suggests a re-evaluation of current diagnostic imaging features and a search for novel imaging approaches, where machine learning is a promising approach.

Importance Risk factors associated with the development of neovascular age-related macular degeneration (AMD) have been identified. However, population size and methods to integrate imaging, genetic, and demographic factors associated with conversion to neovascular AMD are limited, specifically when treatment is administered in 1 eye. Objective To determine the imaging, genetic, and demographic factors associated with conversion from nonneovascular to neovascular AMD in fellow eyes. Design, Setting, and Participants This post hoc secondary analysis of the 24-month phase 3 multicenter, double-masked, active treatment-controlled HARBOR trial included 686 fellow eyes with nonneovascular AMD at baseline. Imaging features describing the presence, number, extent, density, and relative reflectivity of drusen were automatically extracted from spectral-domain optical coherence tomography scans. Genetic analysis included 34 single-nucleotide polymorphisms. Least absolute shrinkage and selection operator regression was performed to narrow imaging features. Survival analysis and Cox proportional hazards regression were performed to determine the association of the selected imaging features and genetic and demographic factors with conversion to neovascular AMD. Data were collected from November 2016 through October 2017 and analyzed from October 2017 through October 2018. Exposure Nonneovascular AMD in the fellow eye. Main Outcomes and Measures Features associated with conversion to neovascular AMD. Hazard ratios (HRs) and their 95% CIs were calculated. Results Among the 686 fellow eyes included in the analysis (406 [59.2%] women; mean [SD] age, 78.12 [8.28] years), 154 (22.4%) converted to neovascular AMD. Female sex was significantly associated with conversion to neovascular AMD (HR, 1.57; 95% CI, 1.11-2.20; P = .009). After controlling for demographic and treatment effects, drusen area within 3 mm of the fovea (HR, 1.45; 95% CI, 1.24-1.69; HR for 1-SD increase, 1.36 [95% CI, 1.20-1.54]) and mean drusen reflectivity (HR, 3.97; 95% CI, 1.11-14.18; HR for 1-SD increase, 1.32 [95% CI, 1.02-1.71]) were significantly associated with conversion to neovascular AMD. In addition, 1 genetic variant (rs61941274) was found to be associated with conversion to neovascular AMD. Conclusions and Relevance Two imaging features (total en face area of drusen restricted to a circular area 3 mm from the fovea and mean drusen reflectivity) and 1 genetic variant ( ACAD10 locus) were associated with conversion to neovascular AMD. Drusen characteristics may be associated with conversion to neovascular AMD despite treatment in 1 eye. Trial Registration ClinicalTrials.gov identifier:NCT00891735

The cell surface HLA-DR molecule binds foreign peptide antigen and forms an intercellular complex with the T cell receptor in the course of the development of an immune response against or immune tolerance to the antigen represented by the bound peptide. The HLA-DR molecule also functions as a receptor that mediates cell signaling pathways, including as yet poorly characterized pathway(s) leading to apoptosis. Expression of HLA-DR mRNA and protein is ordinarily inducible by interferon-γ but is not inducible in tumor cells defective for the retinoblastoma tumor suppressor protein (Rb). In the case of the HLA-DRA gene, which encodes the HLA-DR heavy chain, previous work has indicated that this loss of inducibility is attributable to Oct-1 binding to the HLA-DRA promoter. In this report, we used Oct-1 antisense transformants to determine that Oct-1 represses the interferon-γ response of the endogenous HLA-DRA gene. This determination is consistent with results from a chromatin immunoprecipitation assay, indicating that Oct-1 occupies the endogenous HLA-DRA promoter when the HLA-DRA promoter is inactive in Rb-defective cells but not when the promoter is converted to a previously defined, transcriptionally competent state, induced by treatment of the Rb-defective cells with the HDAC inhibitor, trichostatin A. In vitro DNA-protein binding analyses indicated that Oct-1 prevents HLA-DRA promoter activation by mediating the formation of a complex of proteins, termed DRAN (DRA negative), that blocks NF-Y access to the promoter.

An insulin-responsive line of rat hepatoma cells, H4IIE, was used to investigate the basis for insulin's transcriptional regulation of HMG-CoA reductase. Insulin addition to the media of these cells resulted in at least a 10-fold increase in levels of HMG-CoA reductase protein. Adding insulin to H4IIE cells transfected with pHMGR1 (containing the proximal reductase promoter from -270 to +20 ligated to luciferase) caused greater than 10-fold increases in luciferase activity. Transfections carried out with a series of deletion constructs identified insulin responsive regions between -203 and -130 (contains the SRE sequence) and between -85 and -105 (contains a CRE sequence). Mutation of the SRE in the -203 to -130 sequence did not decrease activation by insulin. In contrast, mutation of the C at -90 of the CRE completely eliminated the insulin response. The data suggest that insulin's activation of HMG-CoA reductase involves the CRE in the -85 to -105 region and the -203 to -130 region of the promoter exclusive of the SRE.

Purpose The purpose of this study was to predict low and high anti-VEGF injection requirements during a pro re nata (PRN) treatment, based on sets of optical coherence tomography (OCT) images acquired during the initiation phase in neovascular AMD. Methods Two-year clinical trial data of subjects receiving PRN ranibizumab according to protocol specified criteria in the HARBOR study after three initial monthly injections were included. OCT images were analyzed at baseline, month 1, and month 2. Quantitative spatio-temporal features computed from automated segmentation of retinal layers and fluid-filled regions were used to describe the macular microstructure. In addition, best-corrected visual acuity and demographic characteristics were included. Patients were grouped into low and high treatment categories based on first and third quartile, respectively. Random forest classification was used to learn and predict treatment categories and was evaluated with cross-validation. Results Of 317 evaluable subjects, 71 patients presented low (≤5), 176 medium, and 70 high (≥16) injection requirements during the PRN maintenance phase from month 3 to month 23. Classification of low and high treatment requirement subgroups demonstrated an area under the receiver operating characteristic curve of 0.7 and 0.77, respectively. The most relevant feature for prediction was subretinal fluid volume in the central 3 mm, with the highest predictive values at month 2. Conclusions We proposed and evaluated a machine learning methodology to predict anti-VEGF treatment needs from OCT scans taken during treatment initiation. The results of this pilot study are an important step toward image-guided prediction of treatment intervals in the management of neovascular AMD.

Objective To evaluate long-term efficacy and safety profiles during 3 years of individualized ranibizumab treatment in patients with visual impairment due to diabetic macular edema (DME). Design Phase IIIb, multicenter, 12-month, randomized core study and 24-month open-label extension study. Participants Of the 303 patients who completed the randomized RESTORE 12-month core study, 240 entered the extension study. Methods In the extension study, patients were eligible to receive individualized ranibizumab treatment as of month 12 guided by best-corrected visual acuity (BCVA) and disease progression criteria at the investigators' discretion. Concomitant laser treatment was allowed according to the Early Treatment Diabetic Retinopathy Study guidelines. Based on the treatments received in the core study, the extension study groups were referred to as prior ranibizumab, prior ranibizumab + laser, and laser. Main Outcome Measures Change in BCVA and incidence of ocular and nonocular adverse events (AEs) over 3 years. Results Overall, 208 patients (86.7%) completed the extension study. In patients treated with ranibizumab during the core study, consecutive individualized ranibizumab treatment during the extension study led to an overall maintenance of BCVA and central retinal subfield thickness (CRST) observed at month 12 over the 2-year extension study (+8.0 letters, −142.1 μm [prior ranibizumab] and +6.7 letters, −145.9 μm [prior ranibizumab + laser] from baseline at month 36) with a median of 6.0 injections (mean, 6.8 injections; prior ranibizumab) and 4.0 (mean, 6.0 injections; prior ranibizumab + laser). In the prior laser group, a progressive BCVA improvement (+6.0 letters) and CRST reduction (−142.7 μm) at month 36 were observed after allowing ranibizumab during the extension study, with a median of 4.0 injections (mean, 6.5 injections) from months 12 to 35. Patients in all 3 treatment groups received a mean of Conclusions Ranibizumab was effective in improving and maintaining BCVA and CRST outcomes with a progressively declining number of injections over 3 years of individualized dosing. Ranibizumab was generally well tolerated with no new safety concerns over 3 years.

To evaluate the efficacy and safety of intravitreal ranibizumab in patients with choroidal neovascularisation secondary to pathological myopia (myopic CNV). Data are from a pre-planned, 6-month interim analysis.Phase II, open-label, single arm, multicentre, 12-month study, recruiting patients (aged ≥18 years) with active primary or recurrent subfoveal or juxtafoveal myopic CNV, with a best-corrected visual acuity (BCVA) score of 24-78 Early Treatment Diabetic Retinopathy Study (ETDRS) letters in the study eye and a diagnosis of high myopia of at least -6 dioptres. Patients received 0.5 mg ranibizumab administered intravitreally to the study eye, followed by monthly injections given as needed (based on a predefined algorithm) for up to 11 months.At 6 months, mean BCVA improved from baseline by 12.2 letters, as did central macular thickness (in this interim analysis defined as a measure of either central subfield macular thickness or centre point macular thickness) from baseline by 108 μm in the 48 study eyes of 48 patients. Fewer patients had centre-involving intraretinal oedema (13.0% vs 91.5%), intraretinal cysts (10.9% vs 57.4%), or subretinal fluid (13.0% vs 66.0%) at 6 months than at baseline. Patients received a mean of 1.9 retreatments, were satisfied with ranibizumab treatment, and well being was maintained. No new safety signals were identified.Results from the planned interim analysis support the role of ranibizumab in the treatment of myopic CNV, with excellent efficacy achieved with a low number of injections and few serious adverse events.

Numerous human tumor lines fail to induce major histocompatibility (MHC) class II expression following interferon-γ (IFN-γ) treatment, a response that is considered to be a normal function for almost all human parenchymal and connective tissue cell-types. The effect of MHC class II non-inducibility on solid tumor growth is controversial, but an extensive body of literature indicates that tumor cell MHC class II expression can lead to an antitumor response or tumor tolerance, depending on a number of variables. Thus, understanding the molecular basis for MHC class II induction failures in solid tumor cells will likely lead to ideas for manipulating the antitumor immune response. To date, a handful of tumor associated molecular anomalies have accounted for all the known failures of MHC class II inducibility. In particular, lack of the retinoblastoma tumor suppressor protein (Rb) has been shown in both human and mouse cells to be strongly associated with failure to induce MHC class II. The basis for this relationship is traceable to, among other things, high level Oct-1 DNA binding activity in Rb-defective cells, which represses the prototypical human MHC class II gene, HLA-DRA. Ordinarily, re-establishment of Rb expression leads to elimination of, or substantially reduced Oct-1 DNA binding activity and to rescue of HLA-DRA inducibility. However, in the case of one non-small cell lung carcinoma line (NSCLC), Rb re-expression failed to rescue HLA-DRA inducibility despite successful re-establishment of Rb-function. We now report that this failure is traceable to the failure of Rb to rescue normal Oct-1 function. Furthermore, histone deacetylase inhibitor treatment allows a bypass of the Rb requirement and facilitates the MHC class II induction in this NSCLC line.

In our studies apolipoprotein E4 (APOE4) is associated with both early- and late-onset Alzheimer's disease. Alzheimer's patients from West Texas were screened for the APOE4 allele, which was found at frequencies of 0.43 and 0.59 in familial late- and early-onset cases. Sporadic cases had lower frequencies, but they still were 2-4 times higher than control spouses. To determine whether the APOE association may be a risk factor for coronary disease as well, we examined two APOB gene restriction sites that have previously been found to be associated with coronary artery disease, especially myocardial infarctions. The APOB alleles were found at similar frequencies in Alzheimer's patients and control spouses.

Following the detection of the rare DRD2 codon 311 variant (Ser{yields}Cys) in an affected member from a large, multiply affected panic disorder family, we investigated the occurrence of this variant in other family members. The variant occurred in both affected and unaffected individuals. Further screening in panic disorder sib pairs unrelated to this family failed to detect the Cys311 variant. Our data suggests that this variant has no pathogenic role in panic disorder. 18 refs., 1 fig.

An association has been observed in several independent data sets between late onset Alzheimer`s Disease (AD) and the APOE locus on chromosome 19. We have examined the genotype in family history positive (FHP) and family history negative (FHN) cases and find a distortion of the APOE allele frequencies in accord with previous studies. However, when we examined the allele distribution of the at-risk siblings of the FHP group we found an excess of the {epsilon}4 allele which also differs significantly from historic controls but not from the affected siblings. The age distribution of the affected and unaffected siblings was similar, suggesting that the allelic frequency distortion in the unaffected siblings was not due to their being below the mean age of onset. Lod score linkage analysis, with age dependent onset and non-stringent specification of the genetic parameters, did not suggest linkage to the APOE locus. Furthermore, an analysis of variance of the age of disease free survival suggested that APOE genotype contributes a small fraction of the total variance indicating that the APOE locus is a poor predictor of disease free survival age within late onset families. One explanation for the age dependent association reported by other groups, and ourmore » results, is that the APOE locus enhances the rate of progression of the disease process in otherwise predisposed individuals and that variation at this locus is not able in and of itself to cause the disease. We suggest this hypothesis is compatible with the current literature regarding APOE and AD. 19 refs., 1 fig., 2 tabs.« less

A mutation in the DRD2 receptor gene has been reported in association with schizophrenia in Japanese and Caucasian populations. The variation, Ser to Cys at codon 311, occurs in the third intracellular loop of the receptor and is therefore putatively functional. We report the results of screening US Caucasian schizophrenic and nonschizophrenic populations. We detected the occurrence of the DRD2 Cys311 variant in both schizophrenics and controls. Our data demonstrates no significant difference between the frequency of Cys311 in Caucasian schizophrenic and non-schizophrenic populations, indicating no association with schizophrenia.