Genetic architecture of the toxicological response to eucalyptol and citronellal in Drosophila melanogaster.

The excessive and indiscriminate use of synthetic insecticides has led to environmental pollution, wildlife destruction, and adverse effects on human health, while simultaneously giving rise to resistance in insect pest populations. This adaptive trait is expressed through various mechanisms, such as changes in the cuticle, heightened activities of detoxifying enzymes, and alterations in the sites of action that reduce their affinity for insecticides. In this context, we associate variation in toxicological response with genomic variation, to identify genetic polymorphisms underlying the different steps of the insect (genotype)-response (phenotype)-insecticide (environment) interaction. Under this framework, our objective was to investigate the genetic factors involved in the toxicological response of D. melanogaster lines when exposed to citronellal and eucalyptol vapors (monoterpenes of plant origin). We quantified KT50 in adult males, representing the time necessary for half of the exposed individuals to be turned upside down (unable to walk or fly). Since the genomes of all lines used are completely sequenced, we perform a Genome Wide Association Study to analyze the genetic underpinnings of the toxicological response. Our investigation enabled the identification of 656 genetic polymorphisms and 316 candidate genes responsible for the overall phenotypic variation. Among these, 162 candidate genes (77.1%) exhibited specificity to citronellal, 45 (21.4%) were specific to eucalyptol, and 3 candidate genes (1.5%) namely CG34345, robo2, and Ac13E, were implicated in the variation for both monoterpenes. These suggest a widespread adaptability in the response to insecticides, encompassing genes influenced by monoterpenes and those orchestrating resistance to the toxicity of these compounds.

Phenotypic variation seems not to be associated with the genetic profile in Zygopetalum (Orchidaceae): a case study of a high-elevation rocky complex.

BACKGROUND: Hybridization associated with polyploidy studies is rare in the tropics. The genus Zygopetalum (Orchidaceae) was investigated here as a case study of Neotropical plants. In the rocky highlands of the Ibitipoca State Park (ISP), southeast Brazil, individuals with intermediate colors and forms between the species Z. maculatum and Z. triste were commonly identified. METHODS AND RESULTS: Chromosomal analysis and DNA quantity showed a uniform population. Regardless of the aspects related to the color and shape of floral structures, all individuals showed 2n = 96 chromosomes and an average of 14.05 pg of DNA. Irregularities in meiosis associated with chromosome number and C value suggest the occurrence of polyploidy. The genetic distance estimated using ISSR molecular markers revealed the existence of genetic variability not related to morphological clusters. Morphometric measurements of the flower pieces revealed that Z. maculatum shows higher variation than Z. triste although lacking a defined circumscription. CONCLUSION: The observed variation can be explained by the polyploid and phenotypic plasticity resulting from the interaction of the genotypes with the heterogeneous environments observed in this habitat.

Association of the rs1966265 and rs351855 FGFR4 Variants with Colorectal Cancer in a Mexican Population and Their Analysis In Silico.

The aim of this study was to associate FGFR4 rs1966265 and rs351855 variants with colorectal cancer (CRC) in a Mexican population and to perform in silico analysis. Genomic DNA from 412 healthy individuals and 475 CRC patients was analyzed. In silico analysis was performed using the PolyPhen-V2, GEPIA, GTEx, and Cytoscape platforms. The GA genotype dominant model (GAAA) of rs1966265 and the AA genotype dominant and recessive models of rs351855 were identified as CRC risk factors (p < 0.05). CRC patients aged ≥ 50 years at diagnosis who consumed alcohol had a higher incidence of the rs351855 GA genotype than the control group (p < 0.05). Associations were observed between the rs1966265 GA genotype and patients with rectal cancer and stage III-IV disease. The rs351855 AA genotype was a risk factor for partial chemotherapy response, and the GA + AA genotype for age ≥ 50 years at diagnosis and rectal cancer was associated with a partial response to chemotherapy (p < 0.05). The AA haplotype was associated with increased susceptibility to CRC. In silico analysis indicated that the rs351855 variant is likely pathogenic (score = 0.998). Genotypic expression analysis in blood samples showed statistically significant differences (p < 0.05). EFNA4, SLC3A2, and HNF1A share signaling pathways with FGFR4. Therefore, rs1966265 and rs351855 may be potential CRC risk factors.

Genetic basis and repeatability for desiccation resistance in Drosophila melanogaster (Diptera: Drosophilidae).

Dehydration is a stress factor for organisms inhabiting natural habitats where water is scarce. Thus, it may be expected that species facing arid environments will develop mechanisms that maximize resistance to desiccation. Insects are excellent models for studying the effects of dehydration as well as the mechanisms and processes that prevent water loss since the effect of desiccation is greater due to the higher area/volume ratio than larger animals. Even though physiological and behavioral mechanisms to cope with desiccation are being understood, the genetic basis underlying the mechanisms related to variation in desiccation resistance and the context-dependent effect remain unsolved. Here we analyze the genetic bases of desiccation resistance in Drosophila melanogaster and identify candidate genes that underlie trait variation. Our quantitative genetic analysis of desiccation resistance revealed sexual dimorphism and extensive genetic variation. The phenotype-genotype association analyses (GWAS) identified 71 candidate genes responsible for total phenotypic variation in desiccation resistance. Half of these candidate genes were sex-specific suggesting that the genetic architecture underlying this adaptive trait differs between males and females. Moreover, the public availability of desiccation data analyzed on the same lines but in a different lab allows us to investigate the reliability and repeatability of results obtained in independent screens. Our survey indicates a pervasive micro-environment lab-dependent effect since we did not detect overlap in the sets of genes affecting desiccation resistance identified between labs.

Genetic, haplotype and phylogenetic analysis of Ligula intestinalis by using mt-CO1 gene marker: ecological implications, climate change and eco-genetic diversity / Análise genética, haplótipo e filogenética de Ligula intestinalis usando marcador do gene mt-CO1: implicações ecológicas, mudanças climáticas e diversidade ecogenética

Ligula intestinalis is a cestode parasite that affects freshwater fish in different countries of the world. The current study aims to reveal the phylogenetic, genetic and haplotype diversity of mt-CO1 gene sequences sent to the NCBI database from different countries by using in-silico analysis. The 105 mt-CO1 (371 bp) gene sequences of L. intestinalis obtained from NCBI were used for bioinformatics analyses. Sequences were subjected to phylogenetic and haplotype analysis. As a result of the haplotype analysis of L. intestinalis, 38 haplotypes were obtained from 13 different countries. Hap24 constituted 44.76% of the obtained haplotype network. Changes in nucleotides between haplotypes occurred at 1-84 different points. China and Turkey have highest fixation index (Fst) values of 0.59761, while the lowest (-0.10526) was found between Russia and Turkey. This study provides a baseline for future studies on extensive scale on the epidemiology, ecological aspects, distribution pattern, transmission dynamics and population dispersion of L. intestinalis worldwide.

Ligula intestinalis é um parasita cestódeo que acomete peixes de água doce em diversos países do mundo. O presente estudo visa revelar a diversidade filogenética, genética e de haplótipos das sequências do gene mt-CO1 enviadas ao banco de dados do NCBI de diferentes países, por meio de análise in-silico. As sequências gênicas de 105 mt-CO1 (371 pb) de L. intestinalis obtidas do NCBI foram utilizadas para análises bioinformáticas. As sequências foram submetidas a análise filogenética e de haplótipos. Como resultado da análise de haplótipos de L. intestinalis, 38 haplótipos foram obtidos de 13 países diferentes. Hap24 constituiu 44,76% da rede de haplótipos obtida. Mudanças nos nucleotídeos entre os haplótipos ocorreram em 1-84 pontos diferentes. A China e a Turquia apresentam os maiores valores do índice de fixação (Fst), 0,59761, enquanto o menor (-0,10526) foi encontrado entre a Rússia e a Turquia. Este estudo fornece uma linha de base para futuros estudos em larga escala sobre epidemiologia, aspectos ecológicos, padrão de distribuição, dinâmica de transmissão e dispersão populacional de L. intestinalis em todo o mundo.

Genetic characterization of domestic pigs in the core zone of swine production of Argentina.

Argentina is a small player in the global pork market, contributing only 0.7% of the total production. With increasing global demand for meat, there is an opportunity for countries with an agricultural profile to grow their pork production. However, there is a need to understand the current state of the pork production sector in all aspects to inform decision-making. The aim of this study was to genetically characterize pig herds from different production strata in the primary region for pork production in the country. For this purpose, phylogenetic and genetic variability analyses were performed using the mitochondrial control region marker (n=95 pig samples). Moreover, genotyping of ryr1 and PRKAG3 genes (n=108 pig samples) were performed to evaluate the frequency of deleterious alleles for meat quality traits in the region. The results showed high levels of genetic variability in the pig herds (Hd= 0.840 ± 0.031 and π= 0.010 ± 0.001), with a creole sow and Iberian lineage standing out in the phylogeny. The genotyping of the ryr1 marker revealed the presence of the deleterious t allele in all analyzed strata. However, the RN-allele of the PRKAG3 gene was detected only in the two lower strata. This study represents the first analysis of the phylogenetic relationships among domestic pigs from Argentina and provides an initial assessment of genetic variability in the region. Additionally, the results present, for the first time, the frequency of deleterious alleles for pig production in the productive core area, demonstrating their prevalence.

FTO genotypes (rs9939609 T>A) are Associated with Increased Added Sugar Intake in Healthy Young Adults.

INTRODUCTION: Single-nucleotide polymorphism (SNP) rs9939609 in the FTO gene has been associated with dietary intake and appetite traits, mainly in participants with obesity; however, it remains widely unexplored in normal weight participants. Thus, the aims of this study were (1) to compare the changes in subjective appetite sensations, ghrelin, and insulin concentrations according to the SNP rs9939609 T>A in FTO and (2) to compare dietary intake between rs9939609 genotype groups in normal weight young participants. METHODS: We conducted a quasi-experimental study involving 88 normal weight participants to analyze subjective perception of appetite, hormonal response for hunger and satiety, and dietary intake according to the rs9939609 SNP. Participants received a standardized single breakfast. Visual analogue scales (VAS) were utilized for assessing the subjective perception of appetite at fasting and immediately after breakfast and at 30, 60, 90, and 120 min postprandially. Glucose, lipid profile, ghrelin, and insulin were measured at fasting and at 120 min after breakfast. Dietary intake was assessed with a 3-day food record. The SNP was determined by allelic discrimination with TaqMan probes. To compare dietetic, biochemical, and the subjective appetite sensations, Student t test, ANCOVA test, and the repeated measures ANOVA were used. The linear regression model and the linear mixed model were used for the association analysis. Pearson correlation was used to test the correlation between two quantitative variables. RESULTS: A total of 88 people participated, 81.8% were female, with a mean body mass index of 21.8 ± 2.0 kg/m2 and a mean age of 20.6 ± 2.0. Genotype frequencies of the rs9939609 SNP were 52% for the TT allele and 48% for the TA/AA. The subjective perception of appetite named hunger, fullness, satiety, desire to eat, and prospective food consumption were similar between genotypes of the rs9939609. Participants with the TA/AA genotype showed a higher intake of added sugar (p = 0.039) than TT participants. No differences were found in ghrelin, insulin, glucose, or lipid parameters between genotypes. CONCLUSION: Carriers of the A allele from FTO gene SNP rs9939609 may have an increased preference for foods, specifically for added sugars.

Association of the rs8720 and rs12587 KRAS Gene Variants with Colorectal Cancer in a Mexican Population and Their Analysis In Silico.

Colorectal cancer (CRC) is a major global health challenge and one of the top 10 cancers in Mexico. Lifestyle and genetic factors influence CRC development, prognosis, and therapeutic response; identifying risk factors, such as the genes involved, is critical to understanding its behavior, mechanisms, and prognosis. The association between KRAS gene variants (rs8720 and rs12587) and CRC in the Mexican population was analyzed. We performed in silico analysis and analyzed 310 healthy individuals and 385 CRC patients using TaqMan assays and real-time PCR. The CC and GG genotypes of rs8720 and rs12587 were identified as CRC risk factors (p < 0.05). The CC and TC genotypes of the rs8720 were associated with rectal cancer, age over 50 years, moderately differentiated histology, and advanced cancer stage. TG and GG genotypes of the rs12587 variant were a risk factor in the CRC group, in patients with stage I-II, males, and stage III-IV non-chemotherapy response. The TG haplotype is protected against CRC. The combined CCGG genotype was linked to CRC risk. In silico analysis revealed that the rs12587 and rs8720 variants could influence KRAS gene regulation via miRNAs. In conclusion, rs8720 and rs12587 variants of the KRAS gene were associated with CRC risk and could influence KRAS regulation via miRNAs.

Prevalence and clinical implications of germline pathogenic variants in cancer predisposing genes in young patients across sarcoma subtypes.

BACKGROUND: Sarcomas are a rare and diverse group of cancers occurring mainly in young individuals for which an underlying germline genetic cause remains unclear in most cases. METHODS: Germline DNA from 177 children, adolescents and young adults with soft tissue or bone sarcomas was tested using multigene panels with 113 or 126 cancer predisposing genes (CPGs) to describe the prevalence of germline pathogenic/likely pathogenic variants (GPVs). Subsequent testing of a subset of tumours for loss of heterozygosity (LOH) evaluation was performed to investigate the clinical and molecular significance of these variants. RESULTS: GPVs were detected in 21.5% (38/177) of the patients (15.8% in children and 21.6% in adolescents and young adults), with dominant CPGs being altered in 15.2% overall. These variants were found in genes previously associated with the risk of developing sarcomas (TP53, RB1, NF1, EXT1/2) but also in genes where that risk is still emerging/limited (ERCC2, TSC2 and BRCA2) or unknown (PALB2, RAD50, FANCM and others). The detection rates of GPVs varied from 0% to 33% across sarcoma subtypes and GPV carriers were more likely to present more than one primary tumour than non-carriers (21.1%×6.5%; p=0.012). Loss of the wild-type allele was detected in 48% of tumours from GPV carriers, mostly in genes definitively associated with sarcoma risk. CONCLUSION: Our findings reveal that a high proportion of young patients with sarcomas presented a GPV in a CPG, underscoring the urgency of establishing appropriate genetic screening strategies for these individuals and their families.

Impact of genetic variations in the WNT family members and RUNX2 on dental and skeletal maturation: a cross-sectional study.

BACKGROUND: This study evaluated if genetic variations in the WNT family members and RUNX2 are associated with craniofacial maturation, investigating dental and skeletal maturity in children and teenagers. METHODS: Radiographs from pre-orthodontic treatment of Brazilian patients (7 to 17 years-old) were used to assess dental (panoramic radiographs) and skeletal maturity (cephalometric radiographs). The chronological age (CA) was calculated based on the date of birth and the time the radiographs were performed. For the dental maturity analysis, the Demirjian (1973) method was used and a delta [dental age - chronological age (DA-CA)] was calculated. For the skeletal maturity analysis, the Baccetti et al. (2005) method was used and the patients were classified as "delayed skeletal maturation", "advanced skeletal maturation" or "normal skeletal maturation". DNA isolated from buccal cells was used for genotyping of two genetic variations in WNT family genes: rs708111 (G > A) in WNT3A and rs1533767 (G > A) in WNT11; and two genetic variations in RUNX2: rs1200425 (G > A) and rs59983488 (G > T). A statistical analysis was performed and values of p < 0.05 indicated a significant difference. RESULTS: There were no associations between dental maturity and genotypes (p > 0.05). In the skeletal maturity analysis, the allele A in the rs708111 (WNT3A) was statistically more frequent in patients with delayed skeletal maturation (Prevalence Ratio = 1.6; 95% Confidence Interval = 1.00 to 2.54; p-value = 0.042). CONCLUSIONS: The rs708111 in the WNT3A gene impacts on skeletal maturation.

Habilidad combinatoria de los caracteres relacionados con la producción de habichuela (Phaseolus vulgaris L.)

Las variedades de habichuela cultivadas en Colombia presentan un bajo potencial de producción, por lo que se hace necesario adelantar programas de mejoramiento, cuya ejecución depende del conocimiento de la habilidad combinatoria de los cultivares disponibles. Con el objetivo de evaluar la acción génica predominante en caracteres de importancia económica, se evaluaron 15 híbridos directos y seis progenitores. Las habilidades combinatorias general (HCG) y específica (HCE), se estimaron con el Método 2 modelo 1 de Griffing, que considera a los progenitores y sus cruzamientos directos. Se midieron los caracteres: número de vainas y producción por planta, peso promedio y longitud de la vaina. Los resultados indicaron efectos genéticos aditivos para longitud de la vaina; por el contrario, el número de vainas y producción por planta, se vieron influenciados por efectos genéticos no aditivos, mientras que el peso promedio de la vaina fue controlado por efectos genéticos, tanto aditivos como no aditivos. Los progenitores 1 y 6 mostraron efectos positivos más altos de HCG, para el peso promedio y longitud de la vaina, mientras los progenitores 5 y 6, lo fueron para la producción de vainas por planta y los progenitores 4 y 5, para el número de vainas por planta. La estimación de HCE más alta para todos los caracteres, se presentó en el hibrido 1x2, siendo la más adecuada para mejorar la producción de la habichuela.

Green bean varieties grown in Colombia have low production potential, therefore it is necessary to carry out plant breeding programs, which execution depends on the knowledge of the combinatorial ability of the available cultivars. To evaluate the predominant gene action in economically important traits 15 direct hybrids and six parents were evaluated. General combining ability (GCA) and specific combining ability (SCA) were estimated with Griffing's Method 2 model 1, which considers parents and their direct crosses. The characters: number of pods and yield per plant, average weight and pod length were measured. The results indicated additive genetic effects for pod length. In contrast, pod number and yield per plant were influenced by non-additive genetic effects, while average pod weight was controlled by both additive and non-additive genetic effects. Parents 1 and 6 showed higher positive effects of HCG for average pod weight and pod length, while parents 5 and 6 for pod yield per plant and parents 4 and 5 for number of pods per plant. The highest ECGH estimation for all traits was found in the 1x2 hybrid, being the most suitable for improving bean production.

Genetics of spontaneous cervical and coronary artery dissections.

Objectives: Spontaneous cervical artery dissections (SCeAD) and coronary artery dissections (SCoAD) are major causes of neurovascular and cardiovascular morbidity in young adults. Although multiple aspects of their etiology are still unknown, most consensuses are focused on the presence of constitutional genetic aspects and environmental triggers. Since recent evidence of genetic contribution points to a possible overlap between these conditions, we aimed to describe current information on SCeAD and SCoAD genetics and their potential shared pathological aspects. Materials and methods: A narrative review is presented. Publications in English and Spanish were queried using database search. The articles were evaluated by one team member in terms of inclusion criteria. After collecting, the articles were categorized based on scientific content. Results: Given that patients with SCeAD and SCoAD rarely present connective tissue disorders, other genetic loci are probably responsible for the increased susceptibility in some individuals. The common variant rs9349379 at PHACTR1 gene is associated with predisposition to pathologies of the arterial wall, likely mediated by variations in Endothelin-1 (ET-1) levels. The risk of arterial dissection may be increased for those who carry the rs9349379(A) allele, associated with lower expression levels of ET-1; however, the local effect of this vasomotor imbalance remains unclear. Sex differences seen in SCeAD and SCoAD support a role for sex hormones that could modulate risk, tilting the delicate balance and forcing vasodilator actions to prevail over vasoconstriction due to a reduction in ET-1 expression. Conclusions: New evidence points to a common gene variation that could explain dissection in both the cervical and coronary vasculatures. To further confirm the risk conferred by the rs9349379 variant, genome wide association studies are warranted, hopefully in larger and ethnically diverse populations.

Investigation of associations between apolipoprotein A5 and C3 gene polymorphisms with plasma triglyceride and lipid levels

SUMMARY OBJECTIVE: The aim of this study was to determine frequency and associations between APOA5 c.56C>G, −1131T>C, c.553G>T, and APOC3 −482C>T and SstI gene polymorphisms with hypertriglyceridemia. METHODS: Under a case-control study model, 135 hypertriglyceridemic and 178 normotriglyceridemic control participants were recruited. Polymerase chain reaction and restriction fragment length polymorphism methods were utilized for genotyping. Statistical calculations were performed by comparing allele and genotype frequencies between groups. Clinical characteristics were compared between groups and intra-group genotypes. RESULTS: APOC3 gene −482C>T and SstI polymorphic genotypes and allele frequencies were significantly higher in hypertriglyceridemic group (genotype frequencies, p=0.035, p=0.028, respectively). Regression analysis under unadjusted model confirmed that APOC3 −482C>T and SstI polymorphisms were significantly contributing to have hypertriglyceridemia (p=0.02, odds ratio [OR]=1.831 (95% confidence interval [CI] 1.095-3.060); p=0.04, OR=1.812 (1.031-3.183), respectively). APOA5 c.56C>G was in complete linkage disequilibrium with APOA5 c.553G>T polymorphism (D'=1). CONCLUSION: For the first time in a population sample from Turkey, among the five polymorphisms of APOA5 and APOC3 genes investigated, APOC3 −482C>T and SstI polymorphisms were associated with elevated serum TG levels, while APOA5 c.56C>G, −1131T>C, and c.553G>T polymorphisms were not.

Mechanisms of robustness in gene regulatory networks involved in neural development.

The functions of living organisms are affected by different kinds of perturbation, both internal and external, which in many cases have functional effects and phenotypic impact. The effects of these perturbations become particularly relevant for multicellular organisms with complex body patterns and cell type heterogeneity, where transcriptional programs controlled by gene regulatory networks determine, for example, the cell fate during embryonic development. Therefore, an essential aspect of development in these organisms is the ability to maintain the functionality of their genetic developmental programs even in the presence of genetic variation, changing environmental conditions and biochemical noise, a property commonly termed robustness. We discuss the implication of different molecular mechanisms of robustness involved in neurodevelopment, which is characterized by the interplay of many developmental programs at a molecular, cellular and systemic level. We specifically focus on processes affecting the function of gene regulatory networks, encompassing transcriptional regulatory elements and post-transcriptional processes such as miRNA-based regulation, but also higher order regulatory organization, such as gene network topology. We also present cases where impairment of robustness mechanisms can be associated with neurodevelopmental disorders, as well as reasons why understanding these mechanisms should represent an important part of the study of gene regulatory networks driving neural development.

Impact of pharmacogenetics on aspirin resistance: a systematic review / Impacto da farmacogenética na resistência à aspirina: uma revisão sistemática

Abstract Background Pharmacogenetics promises better control of diseases such as cardiovascular disease (CVD). Acetylsalicylic acid, aspirin, prevents the formation of an activating agent of platelet aggregation and vasoconstriction, and it is used to prevent CVD. Nevertheless, patients may have treatment failure due to genetic variants that modify the metabolism of the drug causing aspirin resistance (AR). Objectives To realize a systematic literature review to determine the impact of genetic variants on AR. Methods Articles published in the MEDLINE/PubMed, Cochrane, Scopus, LILACS, and SCIELO databases were systematically screened. A total of 290 articles were identified and 269 articles were excluded because they did not comply with the previously established inclusion criteria. A total of 20 case-control studies and 1 cohort was included. Results The genetic variants rs1126643 (ITGA2), rs3842787 (PTGS1), rs20417 (PTGS2), and rs5918 (ITGB3) were the most studied. As for relevance, of the 64 genetic variants evaluated by the articles, 14 had statistical significance (p< 0.05; 95% confidence interval [CI]) in at least one article. Among them, the following have had unanimous results: rs1371097 (P2RY1), rs1045642 (MDR1), rs1051931 and rs7756935 (PLA2G7), rs2071746 (HO1), rs1131882 and rs4523 (TBXA2R), rs434473 (ALOX12), rs9315042 (ALOX5AP), and rs662 (PON1), while these differ in real interference in AR: rs5918 (ITGB3), rs2243093 (GP1BA), rs1330344 (PTGS1), and rs20417 (PTGS2). As study limitations, we highlight the nonuniform methodologies of the analyzed articles and population differences. Conclusion It is noteworthy that pharmacogenetics is an expanding area. Therefore, further studies are needed to better understand the association between genetic variants and AR.

Resumo Antecedentes A farmacogenética promete melhorar o controle de doenças como as cardiovasculares. O ácido acetilsalicílico, a aspirina, previne a formação de um agente ativador da agregação plaquetária e vasoconstrição e é usado na prevenção de tais doenças. No entanto, os pacientes podem ter falha no tratamento devido a variantes genéticas que modificam o metabolismo da droga causando resistência à aspirina (RA). Objetivos Realizar uma revisão sistemática da literatura para determinar o impacto das variantes genéticas na resistência à aspirina. Métodos Artigos publicados nos bancos de dados MEDLINE/PubMed, Cochrane, Scopus, LILACS e SCIELO foram sistematicamente selecionados. Foram identificados 290 artigos e, destes, 269 artigos foram excluídos por não atenderem aos critérios de inclusão previamente estabelecidos. Um total de 20 estudos caso-controles e 1 coorte foi incluído. Resultados As variantes genéticas rs1126643 (ITGA2), rs3842787 (PTGS1), rs20417 (PTGS2) e rs5918 (ITGB3) foram as mais estudadas. Quanto à relevância, das 64 variantes genéticas avaliadas pelos artigos, 14 tiveram significância estatística (p< 0,05; intervalo de confiança [IC] de 95%) em pelo menos um artigo. Entre eles, os seguintes tiveram resultados unânimes: rs1371097 (P2RY1), rs1045642 (MDR1), rs1051931 e rs7756935 (PLA2G7), rs2071746 (HO1), rs1131882 e rs4523 (TBXA2R), rs434473 (ALOX12), rs9315042 (ALOX5AP) e rs662 (PON1), enquanto estes diferiram na interferência real na RA: rs5918 (ITGB3), rs2243093 (GP1BA), rs1330344 (PTGS1) e rs20417 (PTGS2). Como limitações do estudo, destacam-se as metodologias não uniformes dos artigos analisados e as diferenças populacionais. Conclusão Vale ressaltar que a farmacogenética é uma área em expansão. Portanto, mais estudos são necessários para entender melhor a associação entre variantes genéticas e RA.

Demographic changes and life-history strategies predict the genetic diversity in crabs.

Uncovering what predicts genetic diversity (GD) within species can help us access the status of populations and their evolutionary potential. Traits related to effective population size show a proportional association to GD, but evidence supports life-history strategies and habitat as the drivers of GD variation. Instead of investigating highly divergent taxa, focusing on one group could help to elucidate the factors influencing the GD. Additionally, most empirical data is based on vertebrate taxa; therefore, we might be missing novel patterns of GD found in neglected invertebrate groups. Here, we investigated the predictors of the GD in crabs (Brachyura) by compiling the most comprehensive cytochrome c oxidase subunit I (COI) available. Eight predictor variables were analysed across 150 species (16 992 sequences) using linear models (multiple linear regression) and comparative methods (PGLS). Our results indicate that population size fluctuation represents the most critical trait predicting GD, with species that have undergone bottlenecks followed by population expansion showing lower GD. Egg size, pelagic larval duration and habitat might play a role probably because of their association with how species respond to disturbances. Ultimately, K-strategists that have undergone bottlenecks are the species showing lower GD. Some variables do not show an association with GD as expected, most likely due to the taxon-specific role of some predictors, which should be considered in further investigations and generalizations. This work highlights the complexity underlying the predictors of GD and adds results from a marine invertebrate group to the current understanding of this topic.

Population-based analysis of POT1 variants in a cutaneous melanoma case-control cohort.

Pathogenic germline variants in the protection of telomeres 1 gene (POT1) have been associated with predisposition to a range of tumour types, including melanoma, glioma, leukaemia and cardiac angiosarcoma. We sequenced all coding exons of the POT1 gene in 2928 European-descent melanoma cases and 3298 controls, identifying 43 protein-changing genetic variants. We performed POT1-telomere binding assays for all missense and stop-gained variants, finding nine variants that impair or disrupt protein-telomere complex formation, and we further define the role of variants in the regulation of telomere length and complex formation through molecular dynamics simulations. We determine that POT1 coding variants are a minor contributor to melanoma burden in the general population, with only about 0.5% of melanoma cases carrying germline pathogenic variants in this gene, but should be screened in individuals with a strong family history of melanoma and/or multiple malignancies.

Contribution of miR-124 rs531564 polymorphism to the occurrence of congenital Zika syndrome.

Zika virus (ZIKV) cause Congenital Zika Syndrome (CZS) in individuals exposed during pregnancy. Studies have shown that ZIKV infection positively regulates the miR-124 expression in neural cells, which leads to a decrease of TFRC, a gene targeted of this miRNA. Both miR-124 and TFRC exhibit a pivotal role in nervous system development. Therefore, in this study we aimed to investigate whether genetic variants that affect the expression of these genes could act together with ZIKV to increase the risk of individuals developing CZS. TFRC rs406271 and MIR-124-1 rs531564 polymorphisms were genotyped, using TaqMan® Genotyping Assays, in a sample of children who were exposed to ZIKV during pregnancy, of whom 40 were born with CZS and 48 without congenital anomalies. We identified that individuals with CZS presented a higher frequency of CG genotype of rs531564 polymorphism in MIR-124-1 (p=0.048), which is associated with increased expression of miR-124. Since ZIKV also upregulates the expression of this miRNA, the presence of CG genotype in individuals exposed to the virus could lead to a scenario of overexpression of miR-124 in the brain. Since teratogenesis is a multifactorial event, this genetic finding could partly explain why such individuals are more susceptible to CZS, considering both the downregulation of important neurodevelopment genes, as well as deregulation of the neurogenesis process. Thus, we provide preliminary evidence about a possible genetic risk factor to CZS and highlight the importance of analyzing functional polymorphisms related to epigenetic modulators of neurodevelopment genes in the context of ZIKV teratogenesis.

No Association Between Interleukin 6 and Inducible Nitric Oxide Synthase Polymorphisms and Dengue Infection: A Case-Control Study.

BACKGROUND: Dengue is a life-threatening disease. The factors that lead to severe cases are not completely understood. The host immune system is involved in the response to infections and plays an important role in dengue infection. IL-6 and iNOS are components of the immune system and genetic polymorphisms in these genes may be involved in dengue virus infection. The study aimed to investigate the association of genetic polymorphisms in the IL6 and iNOS genes and dengue. METHODS: We performed a case-control study using 60 dengue-infected individuals and 119 healthy controls. Polymorphisms in the IL6 (T15A) and iNOS (-1173CT) genes were amplified by Real-Time PCR. Statistical analyses were performed using BioEstat 5.0. RESULTS: We identified that the frequency of T/A genotype of IL6 was higher in dengue fever patients and C/T genotype of iNOS was higher in dengue hemorrhagic fever patients, however, no association was found between these polymorphisms and dengue. CONCLUSION: Polymorphisms in iNOS and IL6 were not associated with dengue infection.