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Altered immune response during pregnancy has been associated with ASD susceptibility. HLA-G is expressed by the trophoblast at the maternal/fetal interface and induces allogenic tolerance toward the fetus. A 14-bp insertion in the HLA-G 3'UTR (rs371194629) was associated with reduced levels of HLA-G. We aimed to assess the influence of the HLA-G*14 bp indel variant in ASD susceptibility and symptomatology in a Brazilian admixed sample. The insertion genotype (14 bp+/14 bp+) was firstly associated with hetero aggression, but statistical significance was lost after correction (p = 0.035, pcorrected = 0.35). No association between the HLA-G variant and susceptibility to ASD or differential clinical manifestations were observed.

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Autism Spectrum Disorder (ASD) is a set of neurodevelopmental disorders usually observed in early life, with impacts on behavioral and social skills. Incidence of ASD has been dramatically increasing worldwide, possibly due to increase in awareness/diagnosis as well as to genetic and environmental triggers. Currently, it is estimated that ∼1% of the world population presents ASD symptoms. In addition to its genetic background, environmental and immune-related factors also influence the ASD etiology. In this context, maternal immune activation (MIA) has recently been suggested as a component potentially involved in ASD development. In addition, extracellular vesicles (EVs) are abundant at the maternal-fetal interface and are actively involved in the immunoregulation required for a healthy pregnancy. Considering that alterations in concentration and content of EVs have also been associated with ASD, this article raises a debate about the potential roles of EVs in the processes surrounding MIA. This represents the major differential of the present review compared to other ASD studies. To support the suggested correlations and hypotheses, findings regarding the roles of EVs during pregnancy and potential influences on ASD are discussed, along with a review and update concerning the participation of infections, cytokine unbalances, overweight and obesity, maternal anti-fetal brain antibodies, maternal fever, gestational diabetes, preeclampsia, labor type and microbiota unbalances in MIA and ASD.

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Autism Spectrum Disorder (ASD) is a set of neurodevelopmental disorders mainly characterized by repetitive, restrictive and stereotypical behaviors, and impaired communication skills. Several lines of evidence indicate that alterations of the immune system account for ASD development, including the presence of brain-reactive antibodies, abnormal T cell activation, altered cytokine levels in brain, cerebrospinal fluid and peripheral blood circulation, increased levels of circulating monocytes, and dysregulation in Natural Killer (NK) cells activity. Regarding NK cells, a lower cytotoxic activity, a higher level of activation and an increased number of these cells in individuals with ASD have been described. In 2019, a study showed that NK cells derived from patients with ASD show a characteristic pattern of NKG2C overexpression, highlighting the importance of the NK cell pathway in ASD. In fact, the study of genes related to NK cell activity has proven to be an excellent research target, both in terms of susceptibility as well as a marker for the different clinical manifestations observed in ASD individuals. Here, we evaluated the influence of KLRC2 gene deletion as well as KLRK1 rs1049174 and rs2255336 variants in a cohort of 185 children diagnosed with ASD and their respective biological parents in southern Brazil. Of note, this is the first study concerning genetic variants of the KLRC2 and KLRK1 genes in an ASD sample. The KLRC2 gene deletion (p = 0.001; pc = 0.009), KLRK1 rs1049174 (p = 0.005; pc = 0.045) and KLRK1 rs2255336 (p = 0.001; pc = 0.009) were associated with epilepsy in ASD patients. The results indicate that KLRC2 deletion, KLRK1 rs2255336, and KLRK1 rs1049174 could be involved in epilepsy manifestation in ASD patients, possibly impacting the NK dysregulation already described in ASD and epileptic patients.

Assuntos

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Autism spectrum disorder (ASD) is a neurodevelopmental disorder, with strong genetic influences as evidenced by its high heritability. Submicroscopic variations (ranging from one kilobase to several megabases) in DNA, called copy number variations (CNVs), have been associated with psychiatric diseases, including ASD. We aimed to identify CNVs in children diagnosed with idiopathic ASD. We used microarray-based comparative genomic hybridization analysis to detect the CNVs, and bioinformatic tools to evaluate their pathogenic potential, based on predicted functional aspects. Using combined cytogenetic and bioinformatic tools, we identified an autism network of genes/proteins related to the CNVs. Among the 40 children analyzed, we found 14 potentially pathogenic CNVs, including those previously associated with ASD (located at 16p11.2, 15q11.2, and 7p21 regions). We suggest that the most relevant biological process and functional attributes involve olfactory receptors. The CNV-related autism network comprised 90 proteins and 754 nodes and indicated the family of olfactory receptors as a significant pathway in ASD. Olfactory receptors were previously associated with neurologic diseases, and they are possibly related to cognition. This integrative analysis that combines cytogenetics and bioinformatics is a promising approach to understand complex conditions such as ASD.

Assuntos

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There is evidence that dopamine receptors D2 (DRD2) and D4 (DRD4) polymorphisms may influence substance use disorders (SUD) susceptibility both individually and through their influence in the formation of DRD2-DRD4 heteromers. The dopaminergic role on the vulnerability to addiction appears to be influenced by sex. A cross-sectional study with 307 crack cocaine addicts and 770 controls was conducted. The influence of DRD2 rs2283265 and DRD4 48 bp VNTR in exon 3 variants, as well as their interaction on crack cocaine addiction susceptibility and severity were evaluated in women and men separately. An association between the DRD2 T allele and crack cocaine addiction was found in women. In this same group, interaction analysis demonstrated that the presence of DRD2-T allele and concomitant absence of DRD4-7R allele were associated with risk for crack cocaine addiction. No influence of DRD2 and DRD4 variants was observed in men regarding addiction severity. This study reinforces the role of dopaminergic genes in externalizing behaviors, especially the influence of DRD2-DRD4 interaction on SUD. This is the fourth sample that independently associated the DRD2-DRD4 interaction with SUD itself or related disorders. In addition, our findings point out to a potential difference of dopaminergic neurotransmission across sex influencing addiction susceptibility.

Assuntos

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Autism spectrum disorder (ASD) is an early-onset neurodevelopmental disorder characterized by impairments in social behaviors and communication. Oxytocin and its signaling pathway are related to a range of human behaviors, from facial expression recognition to aggressive behaviors, and have been suggested as involved in the etiology of ASD. Our aim was to evaluate the influence of two polymorphisms (rs1042778, rs53576) at the oxytocin receptor gene (OXTR) on ASD diagnosis and on specific ASD-related clinical symptoms (seizures, panic, and aggressive behaviors). We also assessed if these SNPs could be related to changes in OXTR availability and functionality using a bioinformatic approach. The sample was composed by 209 probands with ASD and their biological parents. Family-based approach and logistic regression models were used to investigated the outcomes. We observed that panic and aggressive behaviors were nominally associated with presence of rs1042778 T allele (P = 0.019/Pcorr = 0.114; P = 0.046/Pcorr = 0.276 respectively). Also, in the family-based analysis, a trend towards association with ASD susceptibility was observed for rs1042778 (G allele) (P = 0.066). In a bioinformatic approach, we demonstrated that rs1042778 G allele is determinant for the binding of the transcription factor MAZ, suggesting that when the T allele is present, the absence of MAZ binding might be associated with lower transcription levels of the OXTR gene. The overall findings suggest that the OXTR gene may play a role in ASD diagnosis and some of its clinical phenotypes, supported by previous animal and clinical studies. Further investigations are necessary to replicate our findings and fully understand the effects of the oxytocin pathway on ASD.

Assuntos

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Abstract Musicality is defined as a natural tendency, sensibility, knowledge, or talent to create, perceive, and play music. Musical abilities involve a great range of social and cognitive behaviors, which are influenced by both environmental and genetic factors. Although a number of studies have yielded insights into music genetics research, genes and biological pathways related to these traits are not fully understood. Our hypothesis in the current study is that genes associated with different behaviors could also influence the musical phenotype. Our aim was to investigate whether polymorphisms in six genes (AVPR1A, SLC6A4, ITGB3, COMT, DRD2 and DRD4) related to social and cognitive traits are associated with musicality in a sample of children. Musicality was assessed through an individualized music therapy assessment profile (IMTAP) which has been validated in Brazil to measure musical ability. We show here that the RS1 microsatellite of the AVPR1A gene is nominally associated with musicality, corroborating previous results linking AVPR1A with musical activity. This study is one of the first to investigate musicality in a comprehensive way, and it contributes to better understand the genetic basis underlying musical ability.

RESUMO

Musicality is defined as a natural tendency, sensibility, knowledge, or talent to create, perceive, and play music. Musical abilities involve a great range of social and cognitive behaviors, which are influenced by both environmental and genetic factors. Although a number of studies have yielded insights into music genetics research, genes and biological pathways related to these traits are not fully understood. Our hypothesis in the current study is that genes associated with different behaviors could also influence the musical phenotype. Our aim was to investigate whether polymorphisms in six genes (AVPR1A, SLC6A4, ITGB3, COMT, DRD2 and DRD4) related to social and cognitive traits are associated with musicality in a sample of children. Musicality was assessed through an individualized music therapy assessment profile (IMTAP) which has been validated in Brazil to measure musical ability. We show here that the RS1 microsatellite of the AVPR1A gene is nominally associated with musicality, corroborating previous results linking AVPR1A with musical activity. This study is one of the first to investigate musicality in a comprehensive way, and it contributes to better understand the genetic basis underlying musical ability.

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This study examined the effects of glucocorticoid receptor (NR3C1), corticotropin-releasing hormone receptor 1 (CRHR1), and brain-derived neurotrophic factor (BDNF) genes on susceptibility to crack cocaine addiction and BDNF levels. Crack addicted patients who sought treatment (n = 280) and non-addicted individuals (n = 241) were assessed. Three SNPs in NR3C1 (rs6198, rs41423247, and rs10052957), three in CRHR1 (rs12944712, rs110402, and rs878886), and one in BDNF (rs6265) were genotyped. No significant effect was seen in the case-control analyses. Crack cocaine addicted patients showed significantly lower serum BDNF levels. Significant effects were observed for NR3C1 rs41423247 and rs10052957. These effects were restricted to non-addicted individuals and they were supported by significant gene-by-disease status interactions. For CRHR1, all SNPs were associated with BDNF levels. Although there were significant effects only in the analysis restricted to non-addicted individuals, the lack of significant results in the gene-by-disease status interaction analyses suggest a general effect on BDNF levels. The haplotype analyses presented the same effect seen in the single marker analyses. This study suggests that SNPs in the NR3C1 and CRHR1 genes may influence BDNF levels, but this effect is blunted in the context of crack cocaine addiction. Therefore, our data may be interpreted in light of several studies showing pronounced effects of crack cocaine on BDNF levels. Since peripheral BDNF is a biomarker for several psychiatric phenotypes, our results may be useful in interpreting previous associations between stress-related SNPs, drug addiction, and depression.

Assuntos

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BACKGROUND: This study aims to compare allele and genotype frequencies of a 30-bp variable number of tandem repeats (VNTR) polymorphism of the DAT1 gene, located at intron 8, between adult crack cocaine users and nonaddicted individuals. Due to its involvement in drug addiction, this gene is a good candidate for molecular studies. METHODS: A cross-sectional sample of 239 current adult crack abusers or dependents from in- and outpatient clinics and 211 control individuals was collected in Brazil. They were evaluated using ASRS, ASI-6, WAIS-III, and MINI assessments. DNA samples extracted from whole blood were genotyped for the intron 8 VNTR in DAT1. RESULTS: Logistic regression analysis was performed and controlled for gender, age, ethnicity, educational level, and comorbidities of clinical interest (generalized anxiety disorder, suicide risk, major depressive episode, and attention deficit/hyperactivity disorder). This analysis showed that the 6R6R genotype was associated with crack cocaine addiction (OR = 1.844; CI = 1.101-3.089; p = 0.020). CONCLUSIONS: Our results are consistent with the role of DAT1 in the neurobiology of drug addiction. Nevertheless, the study of other genes, environmental factors, and their interactions is also important to gain a broader understanding of this condition.

Assuntos