MicroRNAs as Diagnostic Biomarkers and Predictors of Antidepressant Response in Major Depressive Disorder: A Systematic Review.

Despite the hardships of major depressive disorder (MDD), biomarkers for the diagnosis and pharmacological management of this condition are lacking. MicroRNAs are epigenetic mechanisms that could provide promising MDD biomarkers. Our aim was to summarize the findings and provide validation for the selection and use of specific microRNAs as biomarkers in the diagnosis and treatment of MDD. A systematic review was conducted using the PubMed/Medline, Cochrane, PsycINFO, Embase, and LILACS databases from March 2022 to November 2023, with clusters of terms based on "microRNA" and "antidepressant". Studies involving human subjects, animal models, and cell cultures were included, whereas those that evaluated herbal medicines, non-pharmacological therapies, or epigenetic mechanisms other than miRNA were excluded. The review revealed differences in the expression of various microRNAs when considering the time of assessment (before or after antidepressant treatment) and the population studied. However, due to the heterogeneity of the microRNAs investigated, the limited size of the samples, and the wide variety of antidepressants used, few conclusions could be made. Despite the observed heterogeneity, the following microRNAs were determined to be important factors in MDD and the antidepressant response: mir-1202, mir-135, mir-124, and mir-16. The findings indicate the potential for the use of microRNAs as biomarkers for the diagnosis and treatment of MDD; however, more homogeneous studies are needed.

The role of IL10 and IL17 gene polymorphisms in treatment response in children and adolescents with severe asthma.

OBJECTIVE: To determine whether polymorphisms of the IL10 and IL17 genes are associated with severe asthma control and bronchodilator reversibility in children and adolescents with severe asthma. METHODS: This was a cross-sectional study, nested within a prospective cohort study of patients with severe asthma. Two outcomes were evaluated: asthma control and bronchodilator reversibility. We extracted DNA from peripheral blood and genotyped three single nucleotide polymorphisms: rs3819024 and rs2275913 in the IL17A gene; and rs3024498 in the IL10 gene. For the association analyses, we performed logistic regression in three genetic models (allelic, additive, and dominant). RESULTS: The rs3024498 C allele in the IL10 gene was associated with failure to achieve asthma control despite regular treatment (p = 0.02). However, the G allele of the IL17A rs3819024 polymorphism was associated with failure to respond to stimulation with a b2 agonist. The rs2275913 polymorphism of the IL17A gene showed no relationship with asthma control or bronchodilator reversibility. CONCLUSIONS: In pediatric patients with severe asthma, the IL10 polymorphism appears to be associated with failure to achieve clinical control, whereas the IL17A polymorphism appears to be associated with a worse bronchodilator response. Knowledge of the involvement of these polymorphisms opens future directions for pharmacogenetic studies and for the implementation of individualized therapeutic management of severe asthma in pediatric patients.

MTOR gene variants are associated with severe COVID-19 outcomes: A multicenter study.

BACKGROUND: The worst outcomes linked to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection have been attributed to the cytokine storm, which contributes significantly to the immunopathogenesis of the disease. The mammalian target of rapamycin (mTOR) pathway is essential for orchestrating innate immune cell defense including cytokine production and is dysregulated in severe Coronavirus Disease 2019 (COVID-19) individuals. The individual genetic background might play a role in the exacerbated immune response. OBJECTIVE: In this study, we aimed to investigate the association between MTOR genetic variants and COVID-19 outcomes. METHODS: This study enrolled groups of individuals with severe (n = 285) and mild (n = 207) COVID-19 from Brazilian states. The MTOR variants, rs1057079 and rs2536, were genotyped. A logistic regression analysis and Kaplan-Meier survival curves were performed. We applied a genotyping risk score to estimate the cumulative contribution of the risk alleles. Tumor necrosis factor (TNF) and interleukin-6 (IL-6) plasma levels were also measured. RESULTS: The T allele of the MTOR rs1057079 variant was associated with a higher likelihood of developing the most severe form of COVID-19. In addition, higher levels of IL-6 and COVID-19 death was linked to the T allele of the rs2536 variant. These variants exhibited a cumulative risk when inherited collectively. CONCLUSIONS: These results show a potential pathogenetic role of MTOR gene variants and may be useful for predicting severe outcomes following COVID-19 infection, resulting in a more effective allocation of health resources.

Genetic variants associated with SARS-CoV-2 infection also affect lung function and asthma severity.

Background: Host genetic factors may be associated with COVID-19 unfavourable outcomes. The first genome-wide association study (GWAS) conducted in individuals with respiratory failure due to COVID-19 revealed susceptibility loci close to six genes (SLC6A20, LZTFL1, CCR9, FYCO1, CXCR6 and XCR1) and the ABO blood-group gene. We aimed to investigate how polymorphisms in those genes could relate to lung function and severe asthma in a Brazilian population. Methods: DNA samples of 784 individuals following the ProAR (Programa para Controle da Asma e Rinite Alérgica da Bahia) were genotyped by the Multi-Ethnic Global Array panel with ∼2 million polymorphisms (Illumina). Polymorphisms in SLC6A20, LZTFL1, CCR9, FYCO1, CXCR6, XCR1 and the ABO blood-group gene were evaluated. Logistic regression for severe asthma, airway obstruction and lack of FEV1 reversibility was performed using PLINK software 1.9, in the additive model and was adjusted for sex, age and PCA-1. Pairwise Linkage disequilibrium analyses were performed using Haploview 4.2. The haplotypes and gene score analyses were performed in the SNPstat tool. In silico functions of polymorphisms were analysed using rSNPbase and RegulomeDB plataforms. Results: We identified the rs8176733 (G allele) and rs8176725 (A allele) in the ABO blood-group gene as risk factors for severe asthma, lower pulmonary obstruction and lack of FEV1 reversibility. Polymorphisms in CCR9 are risk factors for both severe asthma (A allele of rs34338823) and airway obstruction (A allele of rs6806802). The markers rs13079478 (A allele) and rs75817942 (A allele) in FYCO1 are related to more severe asthma and a lack of FEV1 reversibility, respectively. We identified the A allele of both rs35731912 and rs34338823 in LZTFL1 as risk factors for severe asthma. The marker rs6806802 (C allele) was associated with airway obstruction and rs7614952 (A allele), rs7625839 (G allele) and rs112509260 (A allele) are related to a lack of FEV1 reversibility. The A allele of rs2531747 in the SLC6A20 gene is also associated with severe asthma. Conversely, polymorphisms in XCR1 play a protective role in relation to severe asthma (A allele of rs2036295) and airway obstruction (A allele of rs2036295). Additionally, we found that individuals with a higher number of risk alleles have a greater risk of severe asthma, airway obstruction and FEV1 reversibility. Conclusion: Our study suggests that polymorphisms in genes associated with respiratory failure in SARS-CoV-2-infected individuals are associated with greater susceptibility to severe asthma and reduced lung function in subjects with asthma.

The rs2601796 variant in ADCY9 gene is associated with severe asthma and less bronchodilator response.

Asthma is a respiratory disease caused by the interaction of genetic and environmental factors. The adenylyl cyclase type 9 (ADCY9) enzyme produces the cyclic-adenosinemonophosphate (cAMP), important mediator involved in bronchodilation and immunomodulatory response. The aim of this study was to investigate if rs2601796 and rs2532019 variants in the ADCY9 gene are associated with asthma and lung function. The study comprised 1,052 subjects. Logistic regressions were done using PLINK 1.9 adjusted by sex, age, BMI, smoke and principal components. Bronchodilator responsiveness was assessed using the percentage of difference in FEV1 before and after the bronchodilator use. The in silico analysis for gene expression was performed in the GTEx Portal. The variant rs2601796 (AA/AG genotype) was positively associated with asthma severity (OR: 1.60 IC95%: 1.08-2.39) and with obstruction in individuals with severe asthma (OR: 3.10, IC95%: 1.11-8.62). Individuals with severe asthma and the AA/AG genotype of rs2601796 had less responsiveness to bronchodilators and also a lower expression of ADCY9 in lung and whole blood. The variant rs2532019 (TT/GT genotype) also downregulated the ADCY9 gene expression, but no significant association with the studied phenotypes was found. Thus, the variant in ADCY9 was associated with worse asthma outcomes, including a lower response to bronchodilators, likely due to the impact on its gene expression rate. This variant may be useful in the future to assist in personalized management of patients with asthma.

PDE4D gene variants and haplotypes are associated with asthma and atopy in Brazilian children.

PDE4D (Phosphodiesterase 4D) gene encodes a hydrolase of cyclic AMP. PDE4D genetic variants have been associated with asthma susceptibility. Therefore, this study aimed to investigate the association between PDE4D variants (and haplotypes) with asthma and atopy in a Brazilian population. The study comprised 1,246 unrelated participants from the SCAALA (Social Changes Asthma and Allergy in Latin America) program. Genotyping was performed using the Illumina 2.5 Human Omni bead chip. Multivariate logistic regression was used to investigate the association between PDE4D variants and asthma/atopy phenotypes in PLINK 1.09 software. Twenty-four SNVs in PDE4D were associated with atopy or asthma. The rs6898082 (A) variant increased asthma susceptibility (OR 2.76; CI 99% 1.26-6.03) and was also related to a greater PDE4D expression in the GTEx database. Also, the variant rs6870632 was further associated with asthma in meta-analysis with a replication cohort. In addition, the variants rs75699812 (C), rs8007656 (G), and rs958851 (T) were positively associated with atopy. Moreover, these variants formed an atopy risk haplotype (OR 1.82; CI 99% 1.15-2.88). Also, these variants were related to lower levels of IL-10. Functional in silico assessment showed that some PDE4D SNVs may have an impact on gene regulation and expression. Variants in the PDE4D are positively associated with asthma and allergy markers. It is possible that these variants lead to alteration in PDE4D expression and therefore impact immunity and pulmonary function.

Exploring dysregulated immune response genes and endothelial dysfunction biomarkers as predictors of severe COVID-19.

Identifying individuals and factors associated with severe cases of COVID-19 is crucial as the pandemic continues to spread globally. Effective biomarkers for predicting severe cases are essential for optimizing clinical management, therapy, and preventing unfavorable outcomes. This exploratory observational study aimed to investigate the expression of dysregulated immune response genes (ARG1, NOS2, ITGA4, and SELPLG) in total leukocytes, plasmatic levels of P-selectin and PSGL-1, and their clinical associations in patients with mild and severe COVID-19. Data from 117 confirmed COVID-19 patients (severe = 58, mild = 59) were collected upon admission. Gene expression was measured using RT-qPCR, and plasma protein levels assessed with ELISA assay. The severe COVID-19 patient group had a higher median age of 62.0 (p = 0.0001), a higher proportion of black individuals (86.2%, p < 0.0001), and more males (65.5%, p = 0.007). The neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) were significantly higher in the severe COVID-19 patient group (p < 0.0001), indicating ongoing systemic inflammation. Severe COVID-19 patients also exhibited increased expression of ARG1 (p < 0.05) and SELPLG (p < 0.0001) genes, as well as higher concentrations of soluble P-selectin (p < 0.005) and PSGL-1 (p < 0.05) proteins. Multivariate analysis revealed that NLR, PLR, the expression of SELPLG and sPSGL-1 were independent predictors of COVID-19 severity. In conclusion, this study suggests that biomarkers of endothelial dysfunction and dysregulated leukocyte responses are associated with COVID-19 severity, serving as promising predictive tools for optimizing clinical management and patient monitoring.

Understanding and controlling asthma in Latin America: A review of recent research informed by the SCAALA programme.

Asthma is an important health concern in Latin America (LA) where it is associated with variable prevalence and disease burden between countries. High prevalence and morbidity have been observed in some regions, particularly marginalized urban populations. Research over the past 10 years from LA has shown that childhood disease is primarily non-atopic. The attenuation of atopy may be explained by enhanced immune regulation induced by intense exposures to environmental factors such as childhood infections and poor environmental conditions of the urban poor. Non-atopic symptoms are associated with environmental and lifestyle factors including poor living conditions, respiratory infections, psychosocial stress, obesity, and a diet of highly processed foods. Ancestry (particularly African) and genetic factors increase asthma risk, and some of these factors may be specific to LA settings. Asthma in LA tends to be poorly controlled and depends on access to health care and medications. There is a need to improve management and access to medication through primary health care. Future research should consider the heterogeneity of asthma to identify relevant endotypes and underlying causes. The outcome of such research will need to focus on implementable strategies relevant to populations living in resource-poor settings where the disease burden is greatest.

Genetic polymorphism (rs6587666) in FLG protects from eczema in admixed Brazilian children population with high African ancestry.

Genetic variants in filaggrin (FLG) are key in eczema and are less common in Africans than in Europeans and Asians. Here we examined the association between FLG Single Nucleotide Polymorphisms (SNPs) and eczema in a population of admixed Brazilian children and whether African ancestry modifies this association. We included 1010 controls and 137 cases and ran logistic regressions between SNPs in FLG and eczema in the studied population and also stratified the analyses according to the degree of African ancestry. In addition, we tested the replication of the findings on an independent set of individuals, as well as, we verified the impact on FLG expression according to each SNP genotype. The T allele of SNP rs6587666 was negatively associated with eczema in additive model (OR: 0.66, 95% CI: 0.47-0.93, P: 0.017). Moreover, African ancestry modifies the association between rs6587666 and eczema. The effect of the T allele was higher among individuals with higher African ancestry and the association with eczema was lost in individuals with lower African ancestry. In our analyses the expression of FLG in skin was slightly downregulated by the presence of the T allele of rs6587666. In our population, the T allele of rs6587666 in FLG was associated with protection to eczema and the degree of African ancestry was able to modify the observed association.

Variants in interferon gamma inducible protein 16 (IFI16) and absent in melanoma 2 (AIM2) genes that modulate inflammatory response are associated with periodontitis.

OBJECTIVE: Evaluate the association of genetic variants of the interferon gamma inducible protein 16 (IFI16) and absent in melanoma 2 (AIM2) genes with periodontitis. METHODS: The study involved 117 individuals with periodontitis and 389 without periodontitis, all Brazilians, miscegenated. Individuals with periodontitis presented at least 4 teeth with ≥ 1 site with probing depth ≥ 4 mm; clinical attachment level ≥ 3 mm on the same site and bleeding upon stimulus. Genotyping was performed using the Infinium Multi-Ethnic AMR/AFR-8 Bead Chip focused on Hispanic and African American populations with approximately 2 million markers of the human genome. Multivariate logistic regression was performed to identify associations in additive, dominant and recessive models adjusted for covariates age, obesity, mouth breathing, flossing, asthma, and ancestry. RESULTS: In IFI16, the rs75985579-A is positively associated with periodontitis in the additive (Odds Ratio adjusted (ORadjusted) 2.65, 95% confidence interval (CI):1.25-5.60, p value: 0.007) and dominant models (ORadjusted 2.56, 95%CI:1.13-5.81, p value: 0.017). In AIM2, the rs76457189-G, is associated negatively with periodontitis in two genetic models evaluated, additive (ORadjusted 0.21, 95%CI:0.05-0.94, p value: 0.022) and dominant (ORadjusted 0.21, 95%CI:0.05-0.94, p value: 0.022). CONCLUSIONS: These results have shown that variants in the IFI16 and AIM2 genes are associated with periodontitis. Individuals with at least one A (adenine) allele of the rs75985579 (IFI16) are more than twice as likely to have periodontitis, while individuals with the G (guanine) allele of rs76457189 (AIM2) are less likely to be diagnosed with periodontitis, providing a negative association with periodontitis.

The role of IL10 and IL17 gene polymorphisms in treatment response in children and adolescents with severe asthma / O papel de polimorfismos dos genes IL10 e IL17 na resposta ao tratamento em crianças e adolescentes com asma grave

ABSTRACT Objective: To determine whether polymorphisms of the IL10 and IL17 genes are associated with severe asthma control and bronchodilator reversibility in children and adolescents with severe asthma. Methods: This was a cross-sectional study, nested within a prospective cohort study of patients with severe asthma. Two outcomes were evaluated: asthma control and bronchodilator reversibility. We extracted DNA from peripheral blood and genotyped three single nucleotide polymorphisms: rs3819024 and rs2275913 in the IL17A gene; and rs3024498 in the IL10 gene. For the association analyses, we performed logistic regression in three genetic models (allelic, additive, and dominant). Results: The rs3024498 C allele in the IL10 gene was associated with failure to achieve asthma control despite regular treatment (p = 0.02). However, the G allele of the IL17A rs3819024 polymorphism was associated with failure to respond to stimulation with a b2 agonist. The rs2275913 polymorphism of the IL17A gene showed no relationship with asthma control or bronchodilator reversibility. Conclusions: In pediatric patients with severe asthma, the IL10 polymorphism appears to be associated with failure to achieve clinical control, whereas the IL17A polymorphism appears to be associated with a worse bronchodilator response. Knowledge of the involvement of these polymorphisms opens future directions for pharmacogenetic studies and for the implementation of individualized therapeutic management of severe asthma in pediatric patients.

RESUMO Objetivo: Determinar se existe relação entre polimorfismos dos genes IL10 e IL17 e controle da asma grave e reversibilidade com broncodilatador em crianças e adolescentes com asma grave. Métodos: Estudo transversal, aninhado em um estudo prospectivo de coorte com pacientes com asma grave. Foram avaliados dois desfechos: controle da asma e reversibilidade com broncodilatador. Extraímos DNA do sangue periférico e genotipamos três polimorfismos de nucleotídeo único: rs3819024 e rs2275913 no gene IL17A e rs3024498 no gene IL10. Para as análises de associação, realizamos regressão logística em três modelos genéticos (alélico, aditivo e dominante). Resultados: O alelo C do polimorfismo rs3024498 do gene IL10 apresentou relação com asma que permaneceu descontrolada mesmo com tratamento regular (p = 0,02). No entanto, o alelo G do polimorfismo rs3819024 do gene IL17A apresentou relação com ausência de resposta ao estímulo com b2-agonista. O polimorfismo rs2275913 do gene IL17A não apresentou relação com controle da asma ou reversibilidade com broncodilatador. Conclusões: Em pacientes pediátricos com asma grave, o polimorfismo do gene IL10 parece estar relacionado com ausência de controle clínico, ao passo que o polimorfismo do gene IL17A parece estar relacionado com pior resposta ao broncodilatador. O conhecimento a respeito do envolvimento desses polimorfismos abre perspectivas futuras para estudos farmacogenéticos e para a implantação de manejo terapêutico individualizado da asma grave em pacientes pediátricos.

Effects of GRIN2B , GRIA1 , and BDNF Polymorphisms on the Therapeutic Action of Ketamine and Esketamine in Treatment-Resistant Depression Patients: Secondary Analysis From a Randomized Clinical Trial.

OBJECTIVE: This study aimed to evaluate the effect of genetic variants in glutamate ionotropic receptor N-methyl- d -aspartate type subunit 2B ( GRIN2B ), glutamate ionotropic receptor α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid type subunit 1 ( GRIA1 ), and brain-derived neurotrophic factor ( BDNF ) genes on therapeutic response, remission, and total Montgomery-Åsberg Depression Rating Scale scores after treatment with ketamine or esketamine in treatment-resistant depression (TRD) patients. METHODS: Participants (N = 60) are from a double-blind, randomized, noninferiority clinical trial comparing single-dose intravenous ketamine (0.5 mg/kg) to esketamine (0.25 mg/kg) for TRD. Montgomery-Åsberg Depression Rating Scale was applied at baseline, 24 hours, 72 hours, and 7 days postinfusion to assess depressive symptoms. Blood samples were collected to evaluate single nucleotide polymorphisms rs1805502 ( GRIN2B ), rs1994862 ( GRIA1 ), and rs6265 ( BDNF ). RESULTS: There was no association between rs1805502, rs1994862, or rs6265 polymorphisms and antidepressant response ( P = 0.909, P = 0.776, and P = 0.482, respectively), remission P = 0.790, P = 0.086, and P = 0.669), or Montgomery-Åsberg Depression Rating Scale scores at each time point ( P = 0.907, P = 0.552, and P = 0.778). CONCLUSIONS: We found no association between the studied single nucleotide polymorphisms (rs6265, rs1805502, and rs1994862) and ketamine's therapeutic action in TRD patients. Further studies with larger samples are needed to clarify the utility of these genes of interest as predictors for antidepressant treatment.

Impact of FOXP3 gene polymorphisms and gene-environment interactions in asthma and atopy in a Brazilian population.

BACKGROUND: Polymorphisms in genes related to the activation and development of regulatory T cells (Tregs), such as FOXP3, may be associated with asthma and atopy development. Additionally, environmental factors such as exposure to infections can modify the effect of these associations. This study evaluated the impact of polymorphisms in the FOXP3 on the risk of asthma and atopy as also gene-environment interactions in these outcomes. METHODS: This study included 1,246 children from the SCAALA program, between 4 and 11 years of age. DNA was extracted from peripheral blood and eight SNPs (rs2280883, rs11465476, rs11465472, rs2232368, rs3761549, rs3761548, rs2232365 and rs2294021) were genotyped using the 2.5 HumanOmni Beadchip from Illumina (San Diego, California, USA) or TaqMan qRT-PCR. RESULTS: The rs2232368 (Allele T) was positively associated with asthma symptoms (OR = 1.95, CI = 1.04 to 3.66, p = 0.040) and skin prick test (SPT) reactivity to aeroallergens (OR = 2.31, CI = 1.16 to 4.59, p = 0.017). The rs3761549 (Allele T) was positively associated with SPT reactivity (OR = 1.44, CI = 1.03 to 2.02, p = 0.034). The rs2280883 (Allele C) was negatively associated with specific IgE to aeroallergens (OR = 0.83, CI = 0.70 to 0.99, p = 0.040). Furthermore, the rs2280883 played a protective role in the development of atopy only in individuals seropositive to Epstein-Barr virus (EBV) infection (OR = 0.74, CI = 0.60 to 0.92, p = 0.003 and OR = 0.74; 95% CI = 0.61-0.91, p = 0.007 for SPT and slgE respectively), but not in individuals without EBV infection. CONCLUSION: Polymorphisms in the FOXP3 gene were associated with the risk of atopy and asthma development in our population. In addition, EBV infection had an effect modifier of the observed association for rs2280883 variant.

Gene expression profile of chronic oral graft-versus-host disease.

Among the complications observed after allogeneic hematopoietic stem cell transplantation, graft-versus-host disease (GVHD) is the primary cause of post-transplant mortality. The oral cavity is the second most affected organ target in chronic GVHD. Tissue damage results from the upregulation of inflammatory mediators, which play a critical role in the immunopathogenesis of the disease. This case series observational study aims to evaluate the participation of cytokines, chemokines, transcription factors, and heat shock proteins in the pathogenesis of oral GVHD (oGVHD), describing the mRNA expression of 28 genes selected. Peripheral blood mononuclear cells were isolated from six participants with oGVHD and two without GVHD, and relative expression of transcripts with established roles as inflammatory mediators was determined in triplicate using the human RT2 Profiler™ PCR Array. The gene expression levels in the group with oGVHD were mainly up-regulated compared to those without GVHD. PBMC from oGVDH expressed consistently higher IFN-γ, TNF, IL-1ß, CCL2, HSP60 (HSPD1) and HSP90 (HSP90B1). These results can provide a basis for developing new molecular diagnostics and targets therapies for the clinical management of oGVHD.

Variants in proinflammatory genes IL1RL1, IL1B and IRF4 are associated with overweight in a pediatric Brazilian population.

BACKGROUND: Obesity is a chronic complex disease with great prevalence for children all over the world. Characterized for low-grade inflammation associated with several comorbidities such as resistance and type 2 diabetes mellitus (T2DM). OBJECTIVES: To investigate whether genetic variants in IL10, IL1RL1, IL1B, IRF4, TNF, IL6, and IL33 genes are associated with being overweight in children. METHODS: We performed the genotyping of 1004 children using Illumina 2.5 Human Omni bead chip, and association analysis on the genetic variants and the overweight through logistic regression adjusted for sex, age and components principal. RESULTS: Of the seven genes analyzed, 16 SNVs significantly associated. Eleven variants in IL1RL1, two in IL1B and one in IRF4 genes increased overweight risk and two SNVs in IL1RL1 were associated with protection against overweight. The rs2287047-A was negatively associated (OR: 0.66, CI95%: 0.19-0.45) and had a reduced IL1RL1 expression in whole blood (p 0.033) in silico eQTL. The rs12203592-T, in IRF4, was positively associated with being overweight, and led to an increased gene expression in whole blood (p < 0.001) and adipose tissue (p < 0.001). CONCLUSION: These results suggest that genetic variants in inflammatory genes may play an important role in the development of overweight in children.

Heterozygote Advantage of the Type II Deiodinase Thr92Ala Polymorphism on Intrahospital Mortality of COVID-19.

CONTEXT: The type 2 deiodinase and its Thr92Ala-DIO2 polymorphism have been linked to clinical outcomes in acute lung injury and pulmonary fibrosis. OBJECTIVE: Our objectives were to evaluate were cumulative mortality during admission according to Thr92Ala-DIO2 polymorphism. METHODS: Here we conducted an observational, longitudinal, and prospective cohort study to investigate a possible association between the Thr92Ala-DIO2 polymorphism and intrahospital mortality from COVID-19 in adult patients admitted between June and August 2020. Blood biochemistry, thyroid function tests, length of stay, comorbidities, complications, and severity scores were also studied according to Thr92Ala-DIO2 polymorphism. RESULTS: In total, 220 consecutive patients (median age 62; 48-74 years) were stratified into 3 subgroups: Thr/Thr (n = 79), Thr/Ala (n = 119), and Ala/Ala (n = 23). While the overall mortality was 17.3%, the lethality was lower in Ala/Thr patients (12.6%) than in Thr/Thr patients (21.7%) or Ala/Ala patients (23%). The heterozygous genotype (Thr/Ala) was associated with a 47% reduced risk of intrahospital mortality whereas univariate and multivariate logistic regression adjusted for multiple covariates revealed a reduction that ranged from 51% to 66%. The association of the Thr/Ala genotype with better clinical outcomes was confirmed in a metanalysis of 5 studies, including the present one. CONCLUSION: Here we provide evidence for a protective role played by Thr92Ala-DIO2 heterozygosity in patients with COVID-19. This protective effect follows an inheritance model known as overdominance, in which the phenotype of the heterozygote lies outside the phenotypical range of both homozygous.

Zika Virus Congenital Syndrome and MTOR gene variants: insights from a family of dizygotic twins.

Congenital Zika virus syndrome (CZS) is associated with damage to neural progenitor cells by ZIKA virus infection. There are no accurate statistics on the percentage of pregnant mothers who have had babies affected by the syndrome. Few cases of discordant twins have been described in the literature and, therefore, we hypothesize that the genetic background of the progeny and/or mother may play a role in the fate of the syndrome. We performed a complete exome sequencing in a set of dizygotic individuals and their parents. After that, we selected discordant variants on the MTOR gene between the affected and unaffected twin and we observed a mutation (rs2295079), placed in a region restricted to proximal 5'-UTR, as a strong possible causal variant. In addition, in most brain tissues (including fetal brain) evaluated for expression quantitative trait loci (eQTL), this locus is strongly correlated with post-translational modifications of histones (promoter and enhancer marks) and hypersensitivity to DNAse I (open chromatin mark). Taken together, our data suggest that changes in the MTOR gene may be related to CZS. Additional functional studies should be carried out to prove how and why a MTOR mutation can predispose the fetus to the syndrome.

Genetic Determinants of Poor Response to Treatment in Severe Asthma.

Severe asthma is a multifactorial disorder with marked phenotypic heterogeneity and complex interactions between genetics and environmental risk factors, which could, at least in part, explain why during standard pharmacologic treatment, many patients remain poorly controlled and at an increased risk of airway remodeling and disease progression. The concept of "precision medicine" to better suit individual unique needs is an emerging trend in the management of chronic respiratory diseases. Over the past few years, Genome-Wide Association Studies (GWAS) have revealed novel pharmacogenetic variants related to responses to inhaled corticosteroids and the clinical efficacy of bronchodilators. Optimal clinical response to treatment may vary between racial/ethnic groups or individuals due to genetic differences. It is also plausible to assume that epigenetic factors play a key role in the modulation of gene expression patterns and inflammatory cytokines. Remarkably, specific genetic variants related to treatment effectiveness may indicate promising pathways for novel therapies in severe asthma. In this review, we provide a concise update of genetic determinants of poor response to treatment in severe asthma and future directions in the field.

WSB1 and IL21R Genetic Variants Are Involved in Th2 Immune Responses to Ascaris lumbricoides.

Genetic and epigenetic factors are considered to be critical for host-parasite interactions. There are limited data on the role of such factors during human infections with Ascaris lumbricoides. Here, we describe the potential role of genetic factors as determinants of the Th2 immune response to A. lumbricoides in Brazilian children. Stool samples were collected from the children to detect A. lumbricoides by microscopy and peripheral blood leukocytes (PBLs) were cultured in whole blood cultures for detection of cytokines (IL-5, IL-10, and IL-13) in vitro. Levels of anti-A. lumbricoides IgE and IgG4 were measured in plasma. DNA was extracted from PBLs and genotyped using Illumina 2.5 Human Omni Beadchip. Candidate genes associated with A. lumbricoides responses were identified and SNVs in these selected genes associated with the Th2 immune response to A. lumbricoides. Haplotype, gene expression, and epigenetic analyses were done to identify potential associations with Th2 immune responses. GWAS on samples from 1,189 children identified WSB1 as a candidate gene, and IL-21R was selected as a biologically relevant linked gene for further analysis. Variants in WSB1 and IL21R were associated with markers of Th2 immune responses: increased A. lumbricoides-specific IgE and IL-5/IL-13 by PBLs from infected compared to uninfected individuals. In infected children, WSB1 but not IL21R gene expression was suppressed and increased methylation was observed in the WSB1 promoter region. This is the first study to show an association between genetic variants in WSB1 and IL21R and Th2 immune responses during A. lumbricoides infections in children. WSB1/IL21R pathways could provide a potential target for the treatment of Th2-mediated diseases.

ADIPOQ and LEP variants on asthma and atopy: Genetic association modified by overweight.

BACKGROUND: Asthma and atopy are considered condition associated with obesity, being affected by genetic and environmental factors. The LEP and ADIPOQ genes, responsible for the expression and secretion of leptin and adiponectin, respectively, and polymorphisms in such genes have been linked to both diseases, independently, and also with the obesity-associated asthma phenotype in populations with high European ancestry and high-income countries. However, in mixed populations, there are few studies evaluating the impact of these variants in genes associated with the phenotype of asthma and obesity. Thus, the aim of this study was to investigate variants in LEP and ADIPOQ associated with asthma and atopy, and whether overweight modifies that effect. METHODS: The study involved 203 asthmatics children and 813 control subjects (between 5 and 11 years old), with or without overweight, from the SCAALA (Asthma and Allergy Social Changes in Latin America) program. Among them, 831 had data for allergy markers, being 258 atopic and 573 non-atopic. Genotyping was performed using a commercial panel Omnium Illumina 2.5. Logistic regression was performed to identify associations expected by using PLINK 1.09 and three genetic models: additive, dominant and recessive adjusted for sex, age, helminth infection, BMI and Principal Components (PC) 1 and 2, for ancestry, in order to control the confounding factor by population structure. RESULTS: For asthma, G allele of rs822396, in ADIPOQ, was positively associated in additive model (OR 1.4, 95% CI 1.08-1.83) and T allele of rs1063537 in dominant model (OR 1.52, 95% CI 1.01-2.30). In LEP, rs11763517 (C allele) and rs11760956 (A allele) were both negatively associated with asthma in the additive model (OR 0.70, 95% CI 0.54-0.91; OR 0.66, 95% CI 0.50-0.89) respectively, and the A allele of rs2167270 in dominant model (OR 0.71, 95% CI 0.51-0.98). The G allele of rs12706832 showed a positive association with asthma in the recessive model (OR 1.66, 95% CI 1.06-2.61). When the population was stratified by the BMI / Age Z-Score, the protection observed for asthma between the variants rs11760956, rs11763517 and rs2167270 was lost overweight individuals; The protection observed for atopy was lost in all variants (rs16861205, rs2167270 and rs17151919) in the overweight group. CONCLUSION: These results suggest that SNPs on the LEP and ADIPOQ genes may have an impact on atopy and asthma. Furthermore, we also show that the asthma and atopy protection attributed to variants on LEP and ADIPOQ genes is lost in individuals exposed to overweight.