Exploring the relationship between admixture and genetic susceptibility to attention deficit hyperactivity disorder in two Latin American cohorts.

Contemporary research on the genomics of Attention Deficit Hyperactivity Disorder (ADHD) often underrepresents admixed populations of diverse genomic ancestries, such as Latin Americans. This study explores the relationship between admixture and genetic associations for ADHD in Colombian and Mexican cohorts. Some 546 participants in two groups, ADHD and Control, were genotyped with Infinium PsychArray®. Global ancestry levels were estimated using overall admixture proportions and principal component analysis, while local ancestry was determined using a method to estimate ancestral components along the genome. Genome-wide association analysis (GWAS) was conducted to identify significant associations. Differences between Colombia and Mexico were evaluated using appropriate statistical tests. 354 Single-nucleotide polymorphisms (SNPs) and Single-nucleotide variants (SNVs) related to some genes and intergenic regions exhibited suggestive significance (p-value < 5*10e-5) in the GWAS. None of the variants revealed genome-wide significance (p-value < 5*10e-8). The study identified a significant relationship between risk SNPs and the European component of admixture, notably observed in the LOC105379109 gene. Despite differences in risk association loci, such as FOXP2, our findings suggest a possible homogeneity in genetic variation's impact on ADHD between Colombian and Mexican populations. Current reference datasets for ADHD predominantly consist of samples with high European ancestry, underscoring the need for further research to enhance the representation of reference populations and improve the identification of ADHD risk traits in Latin Americans.

Prevalence of Poor Sleep Quality and Associated Factors in Individuals with Rheumatoid Arthritis: A Cross-Sectional Study.

Background and Objectives: Poor sleep quality has been frequently observed in individuals with rheumatoid arthritis. In the present study, we analyzed the presence of poor sleep quality in a sample of Mexican individuals with rheumatoid arthritis; then, we compared sociodemographic and clinical characteristics among patients to determine risk factors for poor sleep quality. Materials and Methods: In this cross-sectional study, we included 102 individuals with rheumatoid arthritis from a hospital in Mexico. We evaluated disease activity (DAS28), quality of sleep using the Pittsburgh Sleep Quality Index, and the presence of depression and anxiety with the Hospital Anxiety and Depression Scale. We performed a Chi-square test and a t-test. Then, we performed a logistic regressions model of the associated features in a univariable analysis. Results: Poor sleep quality was observed in 41.75% of the individuals with rheumatoid arthritis. Being married was a proactive factor (OR 0.04, 95% CI 0.1-0.9, p = 0.04), whereas having one's hips affected or presenting with anxiety and depression was associated with poor sleep quality (OR 4.6, 95% CI 1.2-17.69, p = 0.02). After a multivariate analysis, having anxiety (OR 5.0, 95% CI 1.4-17.7, p < 0.01) and depression (OR 9.2, 95% CI 1.0-8.1, p < 0.01) remained associated with a higher risk of having poor sleep quality. Other clinical characteristics among patients were not significantly different. Conclusions: Our results showed that individuals with rheumatoid arthritis who also presented with depression or anxiety had a higher risk of suffering from poor sleep quality. However, more studies with larger samples are necessary to replicate these results in the Mexican population.

Early intervention in obsessive-compulsive disorder: From theory to practice.

Obsessive-compulsive disorder (OCD) is frequent and often disabling. Yet, correct diagnosis and appropriate treatment implementation are usually delayed, with undesirable consequences. In this paper we review the rationale for early intervention in OCD and provide recommendations for early intervention services. Two scenarios are discussed, i.e., subclinical (prodromal) obsessive-compulsive symptoms (OCS) and full-blown OCD. Although the typical patient with OCD reports a long history of subclinical OCS, longitudinal studies suggest most individuals with OCS in the community do not convert to full-blown OCD. Thus, research on "at risk" phenotypes for OCD and how they should incorporate different risk factors (e.g., polygenic risk scores) are badly needed. For this specific scenario, preventative treatments that are cheap, well tolerated and highly scalable (e.g., lifestyle interventions) are of major interest. On the other hand, increasing evidence suggests OCD to be a progressive disorder and the severity and duration of illness to be associated with both biological changes and increased clinical complexity, including greater number of physical and psychiatric comorbidities, increased family accommodation and worse treatment response. Therefore, prompt identification and early treatment implementation for full-blown OCD are also critical for ethical, clinical and therapeutic reasons. Based on the existing findings, we argue that, regardless of focusing on subclinical OCS or clinical OCD, early intervention services need to target a childhood age group. In addition to delivering well established treatments to people with full-blown OCD early on their illness, early intervention services also need to provide psychoeducation for patients, families and teachers.

The role of gender in a large international OCD sample: A Report from the International College of Obsessive-Compulsive Spectrum Disorders (ICOCS) Network.

INTRODUCTION: Obsessive-compulsive disorder (OCD) is characterized by a range of phenotypic expressions. Gender may be a relevant factor in mediating the disorder's heterogeneity. The aim of the present report was to explore a large multisite clinical sample of OCD patients, hypothesizing existing demographic, geographical and clinical differences between male and female patients with OCD. METHODS: Socio-demographic and clinical variables of 491 adult OCD outpatients recruited in the International College of Obsessive-Compulsive Spectrum Disorders (ICOCS) network were investigated with a retrospective analysis on a previously gathered set of data from eleven countries worldwide. Patients were assessed through structured clinical interviews, the Yale- Brown Obsessive-Compulsive Scale (Y-BOCS), the Montgomery-Asberg Depression Rating Scale (MADRS) and the Self-rating Depression Scale (SDS). RESULTS: Among females, adult onset (>18 years old) was significantly over-represented (67% vs. 33%, p < 0.005), and females showed a significantly older age at illness onset compared with males (20.85 ± 10.76 vs. 17.71 ± 8.96 years, p < 0.005). Females also had a significantly lower education level than males (13.09 ± 4.02 vs. 13.98 ± 3.85 years; p < 0.05), a significantly higher rate of being married (50.8% vs. 33.5%; p < 0.001) and a higher rate of living with a partner (47.5% vs. 37.6%; p < 0.001) than males. Nonetheless, no significant gender differences emerged in terms of the severity of OCD symptoms nor in the severity of comorbid depressive symptoms. No predictive effect of gender was found for Y-BOCS, MADRS and SDS severity. DISCUSSION/CONCLUSIONS: Our findings showed significant differences between genders in OCD. A sexually dimorphic pattern of genetic susceptibility may have a crucial role to OCD clinical heterogeneity, potentially requiring different specific therapeutic strategies. Further research is warranted to validate gender as an important determinant of the heterogeneity in OCD.

Integrative DNA Methylation and Gene Expression Analysis in the Prefrontal Cortex of Mexicans Who Died by Suicide.

BACKGROUND: Suicide represents a major health concern, especially in developing countries. While many demographic risk factors have been proposed, the underlying molecular pathology of suicide remains poorly understood. A body of evidence suggests that aberrant DNA methylation and expression is involved. In this study, we examined DNA methylation profiles and concordant gene expression changes in the prefrontal cortex of Mexicans who died by suicide. METHODS: In collaboration with the coroner's office in Mexico City, brain samples of males who died by suicide (n = 35) and age-matched sudden death controls (n = 13) were collected. DNA and RNA were extracted from prefrontal cortex tissue and analyzed with the Infinium Methylation480k and the HumanHT-12 v4 Expression Beadchips, respectively. RESULTS: We report evidence of altered DNA methylation profiles at 4430 genomic regions together with 622 genes characterized by differential expression in cases vs controls. Seventy genes were found to have concordant methylation and expression changes. Metacore-enriched analysis identified 10 genes with biological relevance to psychiatric phenotypes and suicide (ADCY9, CRH, NFATC4, ABCC8, HMGA1, KAT2A, EPHA2, TRRAP, CD22, and CBLN1) and highlighted the association that ADCY9 has with various pathways, including signal transduction regulated by the cAMP-responsive element modulator, neurophysiological process regulated by the corticotrophin-releasing hormone, and synaptic plasticity. We therefore went on to validate the observed hypomethylation of ADCY9 in cases vs control through targeted bisulfite sequencing. CONCLUSION: Our study represents the first, to our knowledge, analysis of DNA methylation and gene expression associated with suicide in a Mexican population using postmortem brain, providing novel insights for convergent molecular alterations associated with suicide.

Contributions of common genetic variants to risk of schizophrenia among individuals of African and Latino ancestry.

Schizophrenia is a common, chronic and debilitating neuropsychiatric syndrome affecting tens of millions of individuals worldwide. While rare genetic variants play a role in the etiology of schizophrenia, most of the currently explained liability is within common variation, suggesting that variation predating the human diaspora out of Africa harbors a large fraction of the common variant attributable heritability. However, common variant association studies in schizophrenia have concentrated mainly on cohorts of European descent. We describe genome-wide association studies of 6152 cases and 3918 controls of admixed African ancestry, and of 1234 cases and 3090 controls of Latino ancestry, representing the largest such study in these populations to date. Combining results from the samples with African ancestry with summary statistics from the Psychiatric Genomics Consortium (PGC) study of schizophrenia yielded seven newly genome-wide significant loci, and we identified an additional eight loci by incorporating the results from samples with Latino ancestry. Leveraging population differences in patterns of linkage disequilibrium, we achieve improved fine-mapping resolution at 22 previously reported and 4 newly significant loci. Polygenic risk score profiling revealed improved prediction based on trans-ancestry meta-analysis results for admixed African (Nagelkerke's R2 = 0.032; liability R2 = 0.017; P < 10-52), Latino (Nagelkerke's R2 = 0.089; liability R2 = 0.021; P < 10-58), and European individuals (Nagelkerke's R2 = 0.089; liability R2 = 0.037; P < 10-113), further highlighting the advantages of incorporating data from diverse human populations.

Candidate pharmacological treatments for substance use disorder and suicide identified by gene co-expression network-based drug repositioning.

Patients with substance use disorders (SUD) are at high risk to die by suicide. So far, the neurobiology of the suicide-SUD association has not been elucidated. This study aimed to identify potential pharmacological targets among hub genes from brain gene co-expression networks of individuals with SUD in a suicidal and non-suicidal context. Post-mortem samples from the prefrontal cortex of 79 individuals were analyzed. Individuals were classified into the following groups: suicides with SUD (n = 28), suicides without SUD (n = 23), nonsuicides with SUD (n = 9), nonsuicides without SUD (n = 19). Gene expression profiles were evaluated with the Illumina HumanHT-12 v4 array. Co-expression networks were constructed in WGCNA using the differentially expressed genes found in the comparisons: (a) suicides with and without SUD and (b) nonsuicides with and without SUD. Hub genes were selected for drug-gene interaction testing in the DGIdb database. Among drugs interacting with hub genes in suicides we found MAOA inhibitors and dextromethorphan. In the nonsuicide individuals, we found interactions with eglumegad and antipsychotics (olanzapine, clozapine, loxapine). Modafinil was found to interact with genes in both suicides and nonsuicides. These drugs represent possible candidate treatments for patients with SUD with and without suicidal behavior and their study in each context is encouraged.

Orexin-A up-regulates dopamine D2 receptor and mRNA in the nucleus accumbens Shell.

Orexins-A (OrxA) and -B (OrxB) neuropeptides are synthesized by a group of neurons located in the lateral hypothalamus and adjacent perifornical area, which send their projections to the mesolimbic dopaminergic (DAergic) system including ventral tegmental area and nucleus accumbens (NAc), where orexin receptors are expressed. NAc plays a central role in reward-seeking behavior and drug abuse. NAc-neurons express dopamine-1 (D1R) and dopamine-2 (D2R) receptors. Orexins bind to their two cognate G-protein-coupled receptors, orexin-receptor type-1 (Orx1R) and type-2 (Orx2R). Orexin receptor signaling is involved in behaviors such as motivation and addiction. Orexin-containing neurons modulate DAergic activity that is key in synaptic plasticity induced by addictive drugs. However, the effect of OrxA on expression and content of DAergic receptors in NAc is unknown. The purpose of this study was to investigate whether OrxA can alter gene expression and protein levels of D1R/D2R in NAc. Gene expression was evaluated by real-time PCR analysis and protein levels by western blot in rats. The results show that intracerebroventricular (i.c.v.) injection of OrxA increases both gene transcription and protein content of D2R but fails to modify D1R. This effect was also confirmed with OrxA infusion in NAc/Shell. Our results demonstrate for the first time that OrxA induces up-regulation of gene and protein of D2R in NAc. These findings support the hypothesis that OrxA modulates the DAergic transmission and this may serve to understand how orexin signaling enhances DA responses at baseline conditions and in response to psychostimulants.

Lifetime bipolar disorder comorbidity and related clinical characteristics in patients with primary obsessive compulsive disorder: a report from the International College of Obsessive-Compulsive Spectrum Disorders (ICOCS).

INTRODUCTION: Bipolar disorder (BD) and obsessive compulsive disorder (OCD) are prevalent, comorbid, and disabling conditions, often characterized by early onset and chronic course. When comorbid, OCD and BD can determine a more pernicious course of illness, posing therapeutic challenges for clinicians. Available reports on prevalence and clinical characteristics of comorbidity between BD and OCD showed mixed results, likely depending on the primary diagnosis of analyzed samples. METHODS: We assessed prevalence and clinical characteristics of BD comorbidity in a large international sample of patients with primary OCD (n = 401), through the International College of Obsessive-Compulsive Spectrum Disorders (ICOCS) snapshot database, by comparing OCD subjects with vs without BD comorbidity. RESULTS: Among primary OCD patients, 6.2% showed comorbidity with BD. OCD patients with vs without BD comorbidity more frequently had a previous hospitalization (p < 0.001) and current augmentation therapies (p < 0.001). They also showed greater severity of OCD (p < 0.001), as measured by the Yale-Brown Obsessive Compulsive Scale (Y-BOCS). CONCLUSION: These findings from a large international sample indicate that approximately 1 out of 16 patients with primary OCD may additionally have BD comorbidity along with other specific clinical characteristics, including more frequent previous hospitalizations, more complex therapeutic regimens, and a greater severity of OCD. Prospective international studies are needed to confirm our findings.

Brain Gene Expression Profiling of Individuals With Dual Diagnosis Who Died by Suicide.

Objective: Dual diagnosis (DD) is the co-occurrence of at least one substance use disorder and one or more mental disorders in a given individual. Despite this comorbidity being highly prevalent and associated with adverse clinical outcomes, its neurobiology remains unclear. Furthermore, patients with DD are at higher risk for suicidal behavior in comparison with single disorder patients. Our objective was to evaluate brain gene expression patterns in individuals with DD who died by suicide. Methods: We compared the gene expression profile in the dorsolateral prefrontal cortex of suicides with DD (n = 10) to the transcriptome of suicides with substance use disorder alone (n = 10), suicides with mood disorders (MD) alone (n = 13), and suicides without mental comorbidities (n = 5). Gene expression profiles were assessed by microarrays. In addition, we performed a brain cell type enrichment to evaluate whether the gene expression profiles could reflect differences in cell type compositions among the groups. Results: When comparing the transcriptome of suicides with DD to suicides with substance use disorder alone and suicides with MD alone, we identified 255 and 172 differentially expressed genes (DEG), respectively. The overlap of DEG between both comparisons (112 genes) highlighted the presence of common disrupted pathways in substance use disorder and MD. When comparing suicides with DD to suicides without mental comorbidities, we identified 330 DEG, mainly enriched in neurogenesis. Cell type enrichment indicated higher levels of glial markers in suicides with DD compared to the other groups. Conclusions: Suicides with DD exhibited a gene expression profile distinct from that of suicides with a single disorder, being substance use disorder or MD, and suicides without mental disorders. Our results suggest alteration in the expression of genes involved in glial specific markers, glutamatergic and GABAergic neurotransmission in suicides with DD compared to suicides with a single disorder and suicides without mental comorbidities. Alterations in the expression of synaptic genes at different levels were found in substance use disorder and MD.

Brain Gene Expression-DNA Methylation Correlation in Suicide Completers: Preliminary Results.

BACKGROUND: Gene expression alterations have been implicated in suicide pathology. However, the study of the regulatory effect of DNA methylation on gene expression in the suicidal brain has been restricted to candidate genes. OBJECTIVE: The objective of the study was to identify genes whose expression levels are correlated with DNA methylation in the prefrontal cortex of suicides. METHODS: Postmortem prefrontal cortex samples from 21 suicides and six non-suicides were collected. Transcriptomic and DNA methylation profiles were evaluated with microarrays; cis correlations between gene expression and CpG methylation were screened. We then analyzed the presence of transcription factor (TF) binding sites (TFBS) at CpG sites correlated with gene expression. Gene expression of TFs involved in neurodevelopmental binding to predicted TFBS was determined in the BrainSpan database. RESULTS: We identified 22 CpG sites whose methylation levels correlated with gene expression in the prefrontal cortex of suicides. Genes annotated to identified CpG sites were involved in neurodevelopment (BBS4, NKX6-2, AXL, CTNND1, and MBP) and polyamine metabolism (polyamine oxidase [PAOX]). Such correlations were not detected in the nonsuicide group. Nine TFs (USF1, TBP, SF1, NRF1, RFX1, SP3, PKNOX1, MAZ, and POU3F2) showed differential expression in pre- and post-natal developmental periods, according to BrainSpan database. CONCLUSIONS: The integration of different omic technologies provided novel candidates for the investigation of genes whose expression is altered in the suicidal brain and their potential regulatory mechanisms.

Exploratory analysis of genetic variants influencing molecular traits in cerebral cortex of suicide completers.

Genetic factors have been implicated in suicidal behavior. It has been suggested that one of the roles of genetic factors in suicide could be represented by the effect of genetic variants on gene expression regulation. Alteration in the expression of genes participating in multiple biological systems in the suicidal brain has been demonstrated, so it is imperative to identify genetic variants that could influence gene expression or its regulatory mechanisms. In this study, we integrated DNA methylation, gene expression, and genotype data from the prefrontal cortex of suicides to identify genetic variants that could be factors in the regulation of gene expression, generally called quantitative trait locus (xQTLs). We identify 6,224 methylation quantitative trait loci and 2,239 expression quantitative trait loci (eQTLs) in the prefrontal cortex of suicide completers. The xQTLs identified influence the expression of genes involved in neurodevelopment and cell organization. Two of the eQTLs identified (rs8065311 and rs1019238) were previously associated with cannabis dependence, highlighting a candidate genetic variant for the increased suicide risk in subjects with substance use disorders. Our findings suggest that genetic variants may regulate gene expression in the prefrontal cortex of suicides through the modulation of promoter and enhancer activity, and to a lesser extent, binding transcription factors.

Neuroanatomical features and its usefulness in classification of patients with PANDAS.

OBJECTIVE: An obsessive-compulsive disorder (OCD) subtype has been associated with streptococcal infections and is called pediatric autoimmune neuropsychiatric disorders associated with streptococci (PANDAS). The neuroanatomical characterization of subjects with this disorder is crucial for the better understanding of its pathophysiology; also, evaluation of these features as classifiers between patients and controls is relevant to determine potential biomarkers and useful in clinical diagnosis. This was the first multivariate pattern analysis (MVPA) study on an early-onset OCD subtype. METHODS: Fourteen pediatric patients with PANDAS were paired with 14 healthy subjects and were scanned to obtain structural magnetic resonance images (MRI). We identified neuroanatomical differences between subjects with PANDAS and healthy controls using voxel-based morphometry, diffusion tensor imaging (DTI), and surface analysis. We investigated the usefulness of these neuroanatomical differences to classify patients with PANDAS using MVPA. RESULTS: The pattern for the gray and white matter was significantly different between subjects with PANDAS and controls. Alterations emerged in the cortex, subcortex, and cerebellum. There were no significant group differences in DTI measures (fractional anisotropy, mean diffusivity, radial diffusivity, and axial diffusivity) or cortical features (thickness, sulci, volume, curvature, and gyrification). The overall accuracy of 75% was achieved using the gray matter features to classify patients with PANDAS and healthy controls. CONCLUSION: The results of this integrative study allow a better understanding of the neural substrates in this OCD subtype, suggesting that the anatomical gray matter characteristics could have an immune origin that might be helpful in patient classification.

EXPLORATORY ANALYSIS OF RARE AND NOVEL VARIANTS IN MEXICAN PATIENTS DIAGNOSED WITH SCHIZOPHRENIA AND DEMENTIA.

BACKGROUND: Schizophrenia (SCZ) and dementia, often related, are two of the most common neuropsychiatric diseases; epidemiological studies have shown that SCZ patients present a 2-fold increased risk for dementia compared to non-schizophrenic individuals. We explored the presence of rare and novel damaging gene variants in patients diagnosed with late-onset dementia of Alzheimer's type (DAT) or SCZ. METHODS: We included 7 DAT and 12 SCZ patients and performed high-depth targeted sequencing of 184 genes. RESULTS: We found novel and rare damaging variants in 18 genes in these Mexican patients. Carriers of these variants showed extreme phenotypes, including, treatment-resistant SCZ or cognitive decline. Furthermore, we found a variation on ABCC1 as a possible link between psychosis and cognitive impairment. DISCUSSION: As an exploratory analysis, we report some interesting variations that should be corroborated in larger sample size studies.

EXPLORATORY ANALYSIS OF POLYGENIC RISK SCORES FOR PSYCHIATRIC DISORDERS: APPLIED TO DUAL DIAGNOSIS.

BACKGROUND: Concurrence of substance use disorders (SUDs) is high in individuals with psychiatric illnesses; more importantly, individuals with both disorders (dual diagnosis) have more severe symptoms. Psychiatric disorders have been proposed to share a genetic susceptibility with SUDs. To explore this shared genetic susceptibility, we analyzed whether any of the polygenic risk scores (PRSs) for psychiatric disorders could be associated to dual diagnosis in patients with schizophrenia (SCZ) or bipolar disorder (BD). METHODS: We included 192 individuals of Mexican ancestry: 72 with SCZ, 53 with BD, and 67 unrelated controls without psychiatric disorders. We derived calculations of PRS for autism spectrum disorders, attention-deficit/hyperactive disorder, BD, major depression, and SCZ using summary genome-wide association statistics previously published. RESULTS: We found that dual diagnosis had a shared genetic susceptibility with major depressive disorder (MDD) and SCZ; furthermore, in individuals with BD, dual diagnosis could be predicted by PRS for MDD. CONCLUSIONS: Our results reinforce the notion that individuals with dual diagnosis have a higher genetic susceptibility to develop both disorders. However, analyses of larger sample sizes are required to further clarify how to predict risks through PRS within different populations.

Identification of gene ontology and pathways implicated in suicide behavior: Systematic review and enrichment analysis of GWAS studies.

Multiple large-scale studies such as genome-wide association studies (GWAS) have been performed to identify genetic contributors to suicidal behaviors (SB). We aimed to summarize and analyze the information obtained in SB GWAS, to explore the biological process gene ontology (GO) of genes associated with SB from GWAS, and to determine the possible implications of the genes associated with SB in Kyoto encyclopedias of genes and genomes (KEGG) biological pathways. The articles included in the analysis were obtained from PubMed and Scopus databases. Enrichment analyses were performed in Enrichr to evaluate the KEGG pathways and GO of the genes associated with SB of GWAS. The findings of biological process GO analysis showed 924 GO involved in genes related with SB; of those, the regulation of glucose import in response to insulin stimulus, regulation of protein localization to plasma membrane, positive regulation of endopeptidase activity, heterotypic cell-cell adhesion, regulation of cardiac muscle cell contraction, positive regulation of protein localization to plasma membrane, and positive regulation of protein localization to cell periphery biological process GO showed significant statistical association. Furthermore, we obtained 130 KEGG pathways involved in genes related with SB, which Aldosterone synthesis and secretion, Rap1 signaling pathway and arrhythmogenic right ventricular cardiomyopathy pathways showed a significant statistical association. These findings give a better perspective of the biological participation of genes associated with SB, which will be important to perform adequate strategies to prevent and treat SB.

Fine-mapping scan of bipolar disorder susceptibility loci in Latino pedigrees.

We previously identified bipolar disorder (BD) susceptibility loci on 8q24, 14q32, and 2q12-14 in a genome-wide nonparametric linkage screen in a Latino cohort. We now perform a fine mapping analysis using a dense map of additional SNPs to identify BD susceptibility genes within these regions. One thousand nine hundred and thirty-eight individuals with Latino ancestry (880 individuals with BD Type I or Schizoaffective, Bipolar Type) from 416 Latino pedigrees from the United States, Mexico, Costa Rica, and Guatemala were genotyped with 3,074 SNPs to provide dense coverage of the 8q24 (11.5 cM), 14q32 (7.5 cM), and 2q12-14 (6.5 cM) chromosomal loci. Single-marker association tests in the presence of linkage were performed using the LAMP software. The top linkage peak (rs7834818; LOD = 5.08, p = 3.30E - 5) and associated single marker (rs2280915, p = 2.70E - 12) were located within FBXO32 on 8q24. On chromosome 2, the top linkage peak (rs6750326; LOD = 5.06, p = 3.50E - 5) and associated single marker (rs11887088, p = 2.90E - 6) were located in intragenic regions near ACTR3 and DPP10. None of the additional markers in the region around chromosome 14q32 met significance levels for linkage or association. We identified six SNPs on 2q12-q14 and one SNP in FBXO32 on 8q24 that were significantly associated with BD in this Latino cohort.

Prevalence of suicide attempt and clinical characteristics of suicide attempters with obsessive-compulsive disorder: a report from the International College of Obsessive-Compulsive Spectrum Disorders (ICOCS).

OBJECTIVE: Obsessive-compulsive disorder (OCD) is associated with variable risk of suicide and prevalence of suicide attempt (SA). The present study aimed to assess the prevalence of SA and associated sociodemographic and clinical features in a large international sample of OCD patients. METHODS: A total of 425 OCD outpatients, recruited through the International College of Obsessive-Compulsive Spectrum Disorders (ICOCS) network, were assessed and categorized in groups with or without a history of SA, and their sociodemographic and clinical features compared through Pearson's chi-squared and t tests. Logistic regression was performed to assess the impact of the collected data on the SA variable. RESULTS: 14.6% of our sample reported at least one SA during their lifetime. Patients with an SA had significantly higher rates of comorbid psychiatric disorders (60 vs. 17%, p<0.001; particularly tic disorder), medical disorders (51 vs. 15%, p<0.001), and previous hospitalizations (62 vs. 11%, p<0.001) than patients with no history of SA. With respect to geographical differences, European and South African patients showed significantly higher rates of SA history (40 and 39%, respectively) compared to North American and Middle-Eastern individuals (13 and 8%, respectively) (χ2=11.4, p<0.001). The logistic regression did not show any statistically significant predictor of SA among selected independent variables. CONCLUSIONS: Our international study found a history of SA prevalence of ~15% in OCD patients, with higher rates of psychiatric and medical comorbidities and previous hospitalizations in patients with a previous SA. Along with potential geographical influences, the presence of the abovementioned features should recommend additional caution in the assessment of suicide risk in OCD patients.

Astrogliosis and decreased neural viability as consequences of early consumption of aspartame and acesulfame potassium in male Wistar rats.

Artificial sweeteners are mainly used as substitutes for sucrose derivates. In this study, we analyzed if the chronic consumption of aspartame or acesulfame potassium at an early age, produces histological alterations, astrogliosis and decreased neuronal viability, in hippocampus, prefrontal cortex, amygdala and hypothalamus of male Wistar rats. A histological analysis was performed on male Wistar rats that consumed aspartame or acesulfame potassium during 90 days, initiating the consumption of sweeteners immediately after weaning. The evaluation of neuronal morphology in different areas of the brain was performed with hematoxylin - eosin staining. To measure astrogliosis and neuronal viability, we used the immunohistochemical technique, with the glial fibrillary acidic protein immunomodulators (GFAP) and with neuronal-specific enolase (NSE). The consumption of aspartame or acesulfame potassium promoted morphological changes of neurons including increased pyknotic nuclei and vacuolization in all the brain areas studied. In hippocampus, prefrontal cortex, amygdala and hypothalamus, astrogliosis and reduction of neural viability were observed in sweeteners consumers in comparison with the control group. Chronic consumption of ASP and ACK from early stages of development and during long periods, may promote neural modifications, astrogliosis and decrease neuronal viability in prefrontal cortex, amygdala, hippocampus, and hypothalamus.

[Programa de detección del alelo APOE-E4 en adultos mayores mexicanos con deterioro cognitivo].

INTRODUCTION: In Mexico, the prevalence of neurocognitive disorders (NCDs) has increased in parallel with the increase in life expectancy. The E4 allele of the gene that encodes apolipoprotein E (APOE) is the main genetic risk factor for cognitive impairment. OBJECTIVE: To replicate the association of APOE-E4 allele with neurocognitive impairment in a Mexican population, as well as to implement a genetic risk-detection program with the APOE-E4 allele. METHOD: A program was structured for the detection of APOE-E4 allele risk in different recruiting centers from the central zone of the Mexican Republic, with three stages: recruitment and selection of candidates for the detection of the risk-allele, genetic risk analysis and delivery of results. RESULTS: In the genetic-association study to replicate the association with neurocognitive disorders by means of multivariate logistic models, the APOE-E4 allele increased the risk for cognitive impairment in the Mexican populations by approximately 6 % (OR: 5.83, p = 0.0025). In addition, 367 genetic risk results were delivered. CONCLUSIONS: The present program is the first one to be implemented in Mexico with the purpose to inform on a genetic risk factor for neurocognitive disorders in several centers of the country.

INTRODUCCIÓN: En México, la prevalencia de los trastornos neurocognitivos (TNC) han aumentado a la par del incremento en la esperanza de vida. El alelo E4 del gen que codifica la apolipoproteína E (APOE) es el principal factor de riesgo genético para deterioro neurocognitivo. OBJETIVO: Reproducir la asociación en población mexicana entre APOE-E4 y el deterioro neurocognitivo, así como implementar un programa de detección de riesgo genético con el alelo APOE-E4. MÉTODO: Se estructuró un programa de detección de riesgo basado en APO-EA en diferentes centros de reclutamiento en la zona centro de la República Mexicana, con tres etapas: reclutamiento y selección de los candidatos para la detección del alelo de riesgo, análisis del riesgo genético y entrega del resultado. RESULTADOS: El análisis de asociación genética para replicar la asociación con trastornos neurocognitivos mediante modelos logísticos multivariados mostró que el alelo E4 de APOE incrementó aproximadamente 6 % el riesgo en población mexicana (RM = 5.83, p = 0.0025). Se entregaron 367 resultados de riesgo genético. CONCLUSIONES: El presente programa es el primero en México implementado para dar a conocer un factor de riesgo genético para trastornos neurocognitivos en varios centros del país.