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The South American archaeological record has ample evidence of the socio-cultural dynamism of human populations in the past. This has also been supported through the analysis of ancient genomes, by showing evidence of gene flow across the region. While the extent of these signals is yet to be tested, the growing number of ancient genomes allows for more fine-scaled hypotheses to be evaluated. In this study, we assessed the genetic diversity of individuals associated with the Inka ritual, Qhapaq hucha. As part of this ceremony, one or more individuals were buried with Inka and local-style offerings on mountain summits along the Andes, leaving a very distinctive record. Using paleogenomic tools, we analyzed three individuals: two newly generated genomes from El Plomo Mountain (Chile) and El Toro Mountain (Argentina), and a previously published genome from Argentina (Aconcagua Mountain). Our results reveal a complex demographic scenario with each of the individuals showing different genetic affinities. Furthermore, while two individuals showed genetic similarities with present-day and ancient populations from the southern region of the Inka empire, the third individual may have undertaken long-distance movement. The genetic diversity we observed between individuals from similar cultural contexts supports the highly diverse strategies Inka implemented while incorporating new territories. More broadly, this research contributes to our growing understanding of the population dynamics in the Andes by discussing the implications and temporality of population movements in the region.
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Genoma Humano , Humanos , Argentina , Chile , Variação Genética , Diversidade Cultural , Comportamento Ritualístico , Indígenas Sul-Americanos/genética , GenômicaRESUMO
Genomic surveillance (GS) programmes were crucial in identifying and quantifying the mutating patterns of SARS-CoV-2 during the COVID-19 pandemic. In this work, we develop a Bayesian framework to quantify the relative transmissibility of different variants tailored for regions with limited GS. We use it to study the relative transmissibility of SARS-CoV-2 variants in Chile. Among the 3443 SARS-CoV-2 genomes collected between January and June 2021, where sampling was designed to be representative, the Gamma (P.1), Lambda (C.37), Alpha (B.1.1.7), B.1.1.348, and B.1.1 lineages were predominant. We found that Lambda and Gamma variants' reproduction numbers were 5% (95% CI: [1%, 14%]) and 16% (95% CI: [11%, 21%]) larger than Alpha's, respectively. Besides, we observed a systematic mutation enrichment in the Spike gene for all circulating variants, which strongly correlated with variants' transmissibility during the studied period (r = 0.93, p-value = 0.025). We also characterised the mutational signatures of local samples and their evolution over time and with the progress of vaccination, comparing them with those of samples collected in other regions worldwide. Altogether, our work provides a reliable method for quantifying variant transmissibility under subsampling and emphasises the importance of continuous genomic surveillance.
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Teorema de Bayes , COVID-19 , Mutação , SARS-CoV-2 , Chile , Humanos , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , COVID-19/transmissão , COVID-19/virologia , COVID-19/epidemiologia , Genoma Viral , Glicoproteína da Espícula de Coronavírus/genéticaRESUMO
Introduction: Long-term pulmonary dysfunction (L-TPD) is one of the most critical manifestations of long-COVID. This lung affection has been associated with disease severity during the acute phase and the presence of previous comorbidities, however, the clinical manifestations, the concomitant consequences and the molecular pathways supporting this clinical condition remain unknown. The aim of this study was to identify and characterize L-TPD in patients with long-COVID and elucidate the main pathways and long-term consequences attributed to this condition by analyzing clinical parameters and functional tests supported by machine learning and serum proteome profiling. Methods: Patients with L-TPD were classified according to the results of their computer-tomography (CT) scan and diffusing capacity of the lungs for carbon monoxide adjusted for hemoglobin (DLCOc) tests at 4 and 12-months post-infection. Results: Regarding the acute phase, our data showed that L-TPD was favored in elderly patients with hypertension or insulin resistance, supported by pathways associated with vascular inflammation and chemotaxis of phagocytes, according to computer proteomics. Then, at 4-months post-infection, clinical and functional tests revealed that L-TPD patients exhibited a restrictive lung condition, impaired aerobic capacity and reduced muscular strength. At this time point, high circulating levels of platelets and CXCL9, and an inhibited FCgamma-receptor-mediated-phagocytosis due to reduced FcγRIII (CD16) expression in CD14+ monocytes was observed in patients with L-TPD. Finally, 1-year post infection, patients with L-TPD worsened metabolic syndrome and augmented body mass index in comparison with other patient groups. Discussion: Overall, our data demonstrated that CT scan and DLCOc identified patients with L-TPD after COVID-19. This condition was associated with vascular inflammation and impair phagocytosis of virus-antibody immune complexes by reduced FcγRIII expression. In addition, we conclude that COVID-19 survivors required a personalized follow-up and adequate intervention to reduce long-term sequelae and the appearance of further metabolic diseases.
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The mechanisms by which the genotype interacts with nutrition during development to contribute to the variation of complex behaviors and brain morphology of adults are not well understood. Here we use the Drosophila Genetic Reference Panel to identify genes and pathways underlying these interactions in sleep behavior and mushroom body morphology. We show that early-life nutritional restriction effects on sleep behavior and brain morphology depends on the genotype. We mapped genes associated with sleep sensitivity to early-life nutrition, which were enriched for protein-protein interactions responsible for translation, endocytosis regulation, ubiquitination, lipid metabolism, and neural development. By manipulating the expression of candidate genes in the mushroom bodies (MBs) and all neurons, we confirm that genes regulating neural development, translation and insulin signaling contribute to the variable response of sleep and brain morphology to early-life nutrition. We show that the interaction between differential expression of candidate genes with nutritional restriction in early life resides in the MBs or other neurons and that these effects are sex-specific. Natural variations in genes that control the systemic response to nutrition and brain development and function interact with early-life nutrition in different types of neurons to contribute to the variation of brain morphology and adult sleep behavior.
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Drosophila melanogaster , Drosophila , Animais , Masculino , Feminino , Drosophila melanogaster/genética , Drosophila/genética , Encéfalo/fisiologia , Sono/fisiologia , Genes Controladores do DesenvolvimentoRESUMO
Next-generation sequencing (NGS) is progressively being used in clinical practice. However, several barriers preclude using this technology for precision oncology in most Latin American countries. To overcome some of these barriers, we have designed a 25-gene panel that contains predictive biomarkers for most current and near-future available therapies in Chile and Latin America. Library preparation was optimized to account for low DNA integrity observed in formalin-fixed paraffin-embedded tissue. The workflow includes an automated bioinformatic pipeline that accounts for the underrepresentation of Latin Americans in genome databases. The panel detected small insertions, deletions, and single nucleotide variants down to allelic frequencies of 0.05 with high sensitivity, specificity, and reproducibility. The workflow was validated in 272 clinical samples from several solid tumor types, including gallbladder (GBC). More than 50 biomarkers were detected in these samples, mainly in BRCA1/2, KRAS, and PIK3CA genes. In GBC, biomarkers for PARP, EGFR, PIK3CA, mTOR, and Hedgehog signaling inhibitors were found. Thus, this small NGS panel is an accurate and sensitive method that may constitute a more cost-efficient alternative to multiple non-NGS assays and costly, large NGS panels. This kind of streamlined assay with automated bioinformatics analysis may facilitate the implementation of precision medicine in Latin America.
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Polynesia was settled in a series of extraordinary voyages across an ocean spanning one third of the Earth1, but the sequences of islands settled remain unknown and their timings disputed. Currently, several centuries separate the dates suggested by different archaeological surveys2-4. Here, using genome-wide data from merely 430 modern individuals from 21 key Pacific island populations and novel ancestry-specific computational analyses, we unravel the detailed genetic history of this vast, dispersed island network. Our reconstruction of the branching Polynesian migration sequence reveals a serial founder expansion, characterized by directional loss of variants, that originated in Samoa and spread first through the Cook Islands (Rarotonga), then to the Society (Totaiete ma) Islands (11th century), the western Austral (Tuha'a Pae) Islands and Tuamotu Archipelago (12th century), and finally to the widely separated, but genetically connected, megalithic statue-building cultures of the Marquesas (Te Henua 'Enana) Islands in the north, Raivavae in the south, and Easter Island (Rapa Nui), the easternmost of the Polynesian islands, settled in approximately AD 1200 via Mangareva.
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Genoma Humano/genética , Genômica , Migração Humana/história , Havaiano Nativo ou Outro Ilhéu do Pacífico/genética , Feminino , História Medieval , Humanos , Masculino , PolinésiaRESUMO
For human/SARS-CoV-2 interactome genes ACE2, TMPRSS2 and BSG, there is a convincing evidence of association in Asians with influenza-induced SARS for TMPRSS2-rs2070788, tag-SNP of the eQTL rs383510. This case illustrates the importance of population genetics and of sequencing data in the design of genetic association studies in different human populations: the high linkage disequilibrium (LD) between rs2070788 and rs383510 is Asian-specific. Leveraging on a combination of genotyping and sequencing data for Native Americans (neglected in genetic studies), we show that while their frequencies of the Asian tag-SNP rs2070788 is, surprisingly, the highest worldwide, it is not in LD with the eQTL rs383510, that therefore, should be directly genotyped in genetic association studies of SARS in populations with Native American ancestry.
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Chile has high incidence rates of gallbladder cancer globally, particularly among Amerindian women, who also have a high prevalence of gallstones. We examined differences in inflammatory biomarkers between Mapuche and non-Mapuche women from the Chile Biliary Longitudinal Study, a cohort of women with ultrasound-detected gallstones. We randomly selected 200 Mapuche women frequency matched to non-Mapuche women on age and statin use Inflammatory biomarkers were analyzed using a multiplex assay and linear regression to assess associations of a priori markers (CCL20, CXCL10, IL-6, and IL-8) with ethnicity. Novel biomarkers were analyzed using exploratory factor analysis (EFA) and sufficient dimension reduction (SDR) to identify correlated marker groups, followed by linear regression to examine their association with ethnicity. The mean values of IL-8 were higher in Mapuche than non-Mapuche women (P = 0.04), while CCL20, CXCL10, and IL-6 did not differ significantly by ethnicity. EFA revealed two marker groups associated with ethnicity (P = 0.03 and P < 0.001). SDR analysis confirmed correlation between the biomarkers and ethnicity. We found higher IL-8 levels among Mapuche than non-Mapuche women. Novel inflammatory biomarkers were correlated with ethnicity and should be studied further for their role in gallbladder disease. These findings may elucidate underlying ethnic disparities in gallstones and carcinogenesis among Amerindians.
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Quimiocina CCL20/genética , Quimiocina CXCL10/genética , Neoplasias da Vesícula Biliar/sangue , Interleucina-6/genética , Interleucina-8/genética , Idoso , Carcinogênese/genética , Quimiocina CCL20/sangue , Quimiocina CXCL10/sangue , Chile , Etnicidade/genética , Feminino , Vesícula Biliar/diagnóstico por imagem , Vesícula Biliar/metabolismo , Vesícula Biliar/patologia , Neoplasias da Vesícula Biliar/diagnóstico por imagem , Neoplasias da Vesícula Biliar/genética , Neoplasias da Vesícula Biliar/patologia , Cálculos Biliares/diagnóstico por imagem , Cálculos Biliares/metabolismo , Cálculos Biliares/patologia , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Indígenas Sul-Americanos/genética , Inflamação/diagnóstico por imagem , Inflamação/genética , Inflamação/patologia , Interleucina-6/sangue , Interleucina-8/sangue , Estudos Longitudinais , Pessoa de Meia-Idade , UltrassonografiaRESUMO
Chile is one of the largest consumers of sugar-sweetened beverages (SSB) world-wide. However, it is unknown whether the effects from this highly industrialized food will mimic those reported in industrialized countries or whether they will be modified by local lifestyle or population genetics. Our goal is to evaluate the interaction effect between SSB intake and T2D susceptibility on fasting glucose. We calculated a weighted genetic risk score (GRSw) based on 16 T2D risk SNPs in 2828 non-diabetic participants of the MAUCO cohort. SSB intake was categorized in four levels using a food frequency questionnaire. Log-fasting glucose was regressed on SSB and GRSw tertiles while accounting for socio-demography, lifestyle, obesity, and Amerindian ancestry. Fasting glucose increased systematically per unit of GRSw (ß = 0.02 ± 0.006, p = 0.00002) and by SSB intake (ß[cat4] = 0.04 ± 0.01, p = 0.0001), showing a significant interaction, where the strongest effect was observed in the highest GRSw-tertile and in the highest SSB consumption category (ß = 0.05 ± 0.02, p = 0.02). SNP-wise, SSB interacted with additive effects of rs7903146 (TCF7L2) (ß = 0.05 ± 0.01, p = 0.002) and with the G/G genotype of rs10830963 (MTNRB1B) (ß = 0.19 ± 0.05, p = 0.001). Conclusions: The association between SSB intake and fasting glucose in the Chilean population without diabetes is modified by T2D genetic susceptibility.
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Glicemia/metabolismo , Diabetes Mellitus Tipo 2/etiologia , Jejum/sangue , Bebidas Adoçadas com Açúcar/efeitos adversos , Adulto , Idoso , Chile , Estudos Transversais , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/genética , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Estudos Prospectivos , Fatores de RiscoRESUMO
HLA-DRB1 shared epitope (SE) alleles are important genetic contributors for the risk of developing anti-citrullinated protein antibodies (ACPA)-positive rheumatoid arthritis (RA), particularly in Caucasians. We aimed to analyze the contribution of HLA-DRB1 alleles and single nucleotide polymorphisms (SNPs) within the major histocompatibility complex (MHC) region to the susceptibility to develop ACPA-positive RA in a Latin American (LA) population with admixed ancestry. A total of 289 ACPA-positive RA patients and 510 controls were enrolled in this study. The presence of HLA-DRB1*04:01, *09:01 and *10:01 was increased in ACPA-positive RA patients compared with healthy controls (p < 0.0001, p < 0.001 and p < 0.01, respectively), whereas DRB1*07:01 and *08:02 was associated with a decreased risk of ACPA-positive RA (p < 0.001 and p < 0.01, respectively). These results showed a strong correlation with estimates from studies in Asians but not in Caucasian populations. The present study describes the protective effects of the HLA-DRB1*07:01 and *08:02 alleles in ACPA-positive RA patients in a LA population for the first time. Identifying relationships between HLA-DRB1 alleles and RA is important for identifying disease associations in different ethnic groups in order to reach a better understanding of RA worldwide.
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Genetic variants are considered risk factors for gastric cancer. To date, 61 polymorphisms have been identified as associated with this disease. The aim of the present study was to analyze the association of some of those polymorphisms with GC in Chile. We performed a case-control study including 310 gastric cancer cases and 311 controls to assess the association of 36 single-nucleotide polymorphisms genotyped by Global Screening Array (GSA). Three polymorphisms was significantly associated: PSCA rs2294008 (allele model, OR = 1.49, 95%CI 1.17-1.88, P = 1.08 × 10-3), IL-4 rs2243250 (allele model, OR = 1.28, 95%CI 1.01-1.62, P = 0.04), and MUC1 rs4072037 (allele model, OR = 0.78, 95%CI 0.61-0.99, P = 0.04).PSCA rs2294008, IL-4 rs2243250 and MUC1 rs4072037 are associated with gastric cancer in Chile. It suggests that those polymorphisms could be used as biomarkers to assess the genetic risk for this cancer outside of the previously studied populations, not only for East Asians and Caucasians populations.
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Antígenos de Neoplasias/genética , Predisposição Genética para Doença/genética , Interleucina-4/genética , Mucina-1/genética , Proteínas de Neoplasias/genética , Polimorfismo de Nucleotídeo Único , Neoplasias Gástricas/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Estudos de Casos e Controles , Chile , Feminino , Proteínas Ligadas por GPI/genética , Frequência do Gene , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Adulto JovemRESUMO
The possibility of voyaging contact between prehistoric Polynesian and Native American populations has long intrigued researchers. Proponents have pointed to the existence of New World crops, such as the sweet potato and bottle gourd, in the Polynesian archaeological record, but nowhere else outside the pre-Columbian Americas1-6, while critics have argued that these botanical dispersals need not have been human mediated7. The Norwegian explorer Thor Heyerdahl controversially suggested that prehistoric South American populations had an important role in the settlement of east Polynesia and particularly of Easter Island (Rapa Nui)2. Several limited molecular genetic studies have reached opposing conclusions, and the possibility continues to be as hotly contested today as it was when first suggested8-12. Here we analyse genome-wide variation in individuals from islands across Polynesia for signs of Native American admixture, analysing 807 individuals from 17 island populations and 15 Pacific coast Native American groups. We find conclusive evidence for prehistoric contact of Polynesian individuals with Native American individuals (around AD 1200) contemporaneous with the settlement of remote Oceania13-15. Our analyses suggest strongly that a single contact event occurred in eastern Polynesia, before the settlement of Rapa Nui, between Polynesian individuals and a Native American group most closely related to the indigenous inhabitants of present-day Colombia.
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Fluxo Gênico/genética , Genoma Humano/genética , Migração Humana/história , Indígenas Centro-Americanos/genética , Indígenas Sul-Americanos/genética , Ilhas , Havaiano Nativo ou Outro Ilhéu do Pacífico/genética , América Central/etnologia , Colômbia/etnologia , Europa (Continente)/etnologia , Genética Populacional , História Medieval , Humanos , Polimorfismo de Nucleotídeo Único/genética , Polinésia , América do Sul/etnologia , Fatores de TempoRESUMO
BACKGROUND: Current South American populations trace their origins mainly to three continental ancestries, i.e. European, Amerindian and African. Individual variation in relative proportions of each of these ancestries may be confounded with socio-economic factors due to population stratification. Therefore, ancestry is a potential confounder variable that should be considered in epidemiologic studies and in public health plans. However, there are few studies that have assessed the ancestry of the current admixed Chilean population. This is partly due to the high cost of genome-scale technologies commonly used to estimate ancestry. In this study we have designed a small panel of SNPs to accurately assess ancestry in the largest sampling to date of the Chilean mestizo population (n = 3349) from eight cities. Our panel is also able to distinguish between the two main Amerindian components of Chileans: Aymara from the north and Mapuche from the south. RESULTS: A panel of 150 ancestry-informative markers (AIMs) of SNP type was selected to maximize ancestry informativeness and genome coverage. Of these, 147 were successfully genotyped by KASPar assays in 2843 samples, with an average missing rate of 0.012, and a 0.95 concordance with microarray data. The ancestries estimated with the panel of AIMs had relative high correlations (0.88 for European, 0.91 for Amerindian, 0.70 for Aymara, and 0.68 for Mapuche components) with those obtained with AXIOM LAT1 array. The country's average ancestry was 0.53 ± 0.14 European, 0.04 ± 0.04 African, and 0.42 ± 0.14 Amerindian, disaggregated into 0.18 ± 0.15 Aymara and 0.25 ± 0.13 Mapuche. However, Mapuche ancestry was highest in the south (40.03%) and Aymara in the north (35.61%) as expected from the historical location of these ethnic groups. We make our results available through an online app and demonstrate how it can be used to adjust for ancestry when testing association between incidence of a disease and nongenetic risk factors. CONCLUSIONS: We have conducted the most extensive sampling, across many different cities, of current Chilean population. Ancestry varied significantly by latitude and human development. The panel of AIMs is available to the community for estimating ancestry at low cost in Chileans and other populations with similar ancestry.
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Etnicidade/genética , Genética Populacional/organização & administração , Indígenas Sul-Americanos/genética , Polimorfismo de Nucleotídeo Único/genética , Grupos Populacionais/genética , Chile , Feminino , Frequência do Gene/genética , Marcadores Genéticos/genética , Genótipo , Técnicas de Genotipagem , Humanos , Masculino , Filogeografia , SalivaRESUMO
BACKGROUND: Current South American populations trace their origins mainly to three continental ancestries, i.e. European, Amerindian and African. Individual variation in relative proportions of each of these ancestries may be confounded with socio-economic factors due to population stratification. Therefore, ancestry is a potential confounder variable that should be considered in epidemiologic studies and in public health plans. However, there are few studies that have assessed the ancestry of the current admixed Chilean population. This is partly due to the high cost of genome-scale technologies commonly used to estimate ancestry. In this study we have designed a small panel of SNPs to accurately assess ancestry in the largest sampling to date of the Chilean mestizo population (n = 3349) from eight cities. Our panel is also able to distinguish between the two main Amerindian components of Chileans: Aymara from the north and Mapuche from the south. RESULTS: A panel of 150 ancestry-informative markers (AIMs) of SNP type was selected to maximize ancestry informativeness and genome coverage. Of these, 147 were successfully genotyped by KASPar assays in 2843 samples, with an average missing rate of 0.012, and a 0.95 concordance with microarray data. The ancestries estimated with the panel of AIMs had relative high correlations (0.88 for European, 0.91 for Amerindian, 0.70 for Aymara, and 0.68 for Mapuche components) with those obtained with AXIOM LAT1 array. The country's average ancestry was 0.53 ± 0.14 European, 0.04 ± 0.04 African, and 0.42 ± 0.14 Amerindian, disaggregated into 0.18 ± 0.15 Aymara and 0.25 ± 0.13 Mapuche. However, Mapuche ancestry was highest in the south (40.03%) and Aymara in the north (35.61%) as expected from the historical location of these ethnic groups. We make our results available through an online app and demonstrate how it can be used to adjust for ancestry when testing association between incidence of a disease and nongenetic risk factors. CONCLUSIONS: We have conducted the most extensive sampling, across many different cities, of current Chilean population. Ancestry varied significantly by latitude and human development. The panel of AIMs is available to the community for estimating ancestry at low cost in Chileans and other populations with similar ancestry.
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Humanos , Masculino , Feminino , Etnicidade/genética , Indígenas Sul-Americanos/genética , Polimorfismo de Nucleotídeo Único/genética , Grupos Populacionais/genética , Genética Populacional/organização & administração , Saliva , Marcadores Genéticos/genética , Chile , Filogeografia , Técnicas de Genotipagem , Frequência do Gene/genética , GenótipoRESUMO
Maqui (Aristotelia chilensis [Molina] Stunz) is a small dioecious tree, belonging to the Elaeocarpaceae family. Maqui fruit has high levels of antioxidant activity, which are due to elevated anthocyanin and polyphenol content. Here we describe a draft genome sequence data of maqui (A. chilensis). The genomic sequence datasets were obtained using Illumina NextSeq platform. Nucleotide sequences of raw reads and the assembled draft genome are available at NCBI's Sequence Read Archive as BioProject PRJNA544858. Also, a total of 210067 microsatellite or simple sequence repeat (SSR) markers were identified.
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Histone Gene Cluster 1 Member E, HIST1H1E, encodes Histone H1.4, is one of a family of epigenetic regulator genes, acts as a linker histone protein, and is responsible for higher order chromatin structure. HIST1H1E syndrome (also known as Rahman syndrome, OMIM #617537) is a recently described intellectual disability (ID) syndrome. Since the initial description of five unrelated individuals with three different heterozygous protein-truncating variants (PTVs) in the HIST1H1E gene in 2017, we have recruited 30 patients, all with HIST1H1E PTVs that result in the same shift in frame and that cluster to a 94-base pair region in the HIST1H1E carboxy terminal domain. The identification of 30 patients with HIST1H1E variants has allowed the clarification of the HIST1H1E syndrome phenotype. Major findings include an ID and a recognizable facial appearance. ID was reported in all patients and is most frequently of moderate severity. The facial gestalt consists of a high frontal hairline and full lower cheeks in early childhood and, in later childhood and adulthood, affected individuals have a strikingly high frontal hairline, frontal bossing, and deep-set eyes. Other associated clinical features include hypothyroidism, abnormal dentition, behavioral issues, cryptorchidism, skeletal anomalies, and cardiac anomalies. Brain magnetic resonance imaging (MRI) is frequently abnormal with a slender corpus callosum a frequent finding.
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Fácies , Histonas/genética , Deficiência Intelectual/genética , Mutação/genética , Comportamento , Crescimento e Desenvolvimento , Heterozigoto , Humanos , Aprendizagem , Fenótipo , SíndromeRESUMO
The potential of tolerogenic dendritic cells (tolDCs) to shape immune responses and restore tolerance has turn them into a promising therapeutic tool for cellular therapies directed toward immune regulation in autoimmunity. Although the cellular mechanisms by which these cells can exert their regulatory function are well-known, the mechanisms driving their differentiation and function are still poorly known, and the variety of stimuli and protocols applied to differentiate DCs toward a tolerogenic phenotype makes it even more complex to underpin the molecular features involved in their function. Through transcriptional profiling analysis of monocyte-derived tolDCs modulated with dexamethasone (Dex) and activated with monophosphoryl lipid A (MPLA), known as DM-DCs, we were able to identify MYC as one of the transcriptional regulators of several genes differentially expressed on DM-DCs compared to MPLA-matured DCs (M-DCs) and untreated/immature DCs (DCs) as revealed by Ingenuity Pathway Analysis (IPA) upstream regulators evaluation. Additionally, MYC was also amidst the most upregulated genes in DM-DCs, finding that was confirmed at a transcriptional as well as at a protein level. Blockade of transactivation of MYC target genes led to the downregulation of tolerance-related markers IDO1 and JAG1. MYC blockade also led to downregulation of PLZF and STAT3, transcription factors associated with immune regulation and inhibition of DC maturation, further supporting a role of MYC as an upstream regulator contributing to the regulatory phenotype of DM-DCs. On the other hand, we had previously shown that fatty acid oxidation, oxidative metabolism and zinc homeostasis are amongst the main biological functions represented in DM-DCs, and here we show that DM-DCs exhibit higher intracellular expression of ROS and Zinc compared to mature M-DCs and DCs. Taken together, these findings suggest that the regulatory profile of DM-DCs is partly shaped by the effect of the transcriptional regulation of tolerance-inducing genes by MYC and the modulation of oxidative metabolic processes and signaling mediators such as Zinc and ROS.
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Células Dendríticas/metabolismo , Dexametasona/farmacologia , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica/efeitos dos fármacos , Genes myc/genética , Lipídeo A/análogos & derivados , Adulto , Diferenciação Celular/genética , Células Cultivadas , Células Dendríticas/imunologia , Feminino , Regulação da Expressão Gênica/imunologia , Humanos , Tolerância Imunológica/genética , Tolerância Imunológica/imunologia , Lipídeo A/farmacologia , Masculino , Pessoa de Meia-Idade , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Regulação para Cima/efeitos dos fármacos , Adulto JovemRESUMO
The peopling of the Andean highlands above 2500 m in elevation was a complex process that included cultural, biological, and genetic adaptations. Here, we present a time series of ancient whole genomes from the Andes of Peru, dating back to 7000 calendar years before the present (BP), and compare them to 42 new genome-wide genetic variation datasets from both highland and lowland populations. We infer three significant features: a split between low- and high-elevation populations that occurred between 9200 and 8200 BP; a population collapse after European contact that is significantly more severe in South American lowlanders than in highland populations; and evidence for positive selection at genetic loci related to starch digestion and plausibly pathogen resistance after European contact. We do not find selective sweep signals related to known components of the human hypoxia response, which may suggest more complex modes of genetic adaptation to high altitude.
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Adaptação Fisiológica/genética , DNA Antigo/análise , Genética Populacional , Genoma Humano , Hipóxia/genética , Indígenas Sul-Americanos/genética , Polimorfismo de Nucleotídeo Único , Genótipo , Humanos , Dinâmica Populacional , Análise de Sequência de DNA , Sequenciamento Completo do GenomaRESUMO
BACKGROUND: Whole transcriptome RNA variant analyses have shown that adenosine deaminases acting on RNA (ADAR) enzymes modify a large proportion of cellular RNAs, contributing to transcriptome diversity and cancer evolution. Despite the advances in the understanding of ADAR function in breast cancer, ADAR RNA editing functional consequences are not fully addressed. RESULTS: We characterized A to G(I) mRNA editing in 81 breast cell lines, showing increased editing at 3'UTR and exonic regions in breast cancer cells compared to immortalized non-malignant cell lines. In addition, tumors from the BRCA TCGA cohort show a 24% increase in editing over normal breast samples when looking at 571 well-characterized UTRs targeted by ADAR1. Basal-like subtype breast cancer patients with high level of ADAR1 mRNA expression shows a worse clinical outcome and increased editing in their 3'UTRs. Interestingly, editing was particularly increased in the 3'UTRs of ATM, GINS4 and POLH transcripts in tumors, which correlated with their mRNA expression. We confirmed the role of ADAR1 in this regulation using a shRNA in a breast cancer cell line (ZR-75-1). CONCLUSIONS: Altogether, these results revealed a significant association between the mRNA editing in genes related to cancer-relevant pathways and clinical outcomes, suggesting an important role of ADAR1 expression and function in breast cancer.
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Regiões 3' não Traduzidas/genética , Adenosina Desaminase/genética , Neoplasias da Mama/genética , Edição de RNA/genética , Estabilidade de RNA/genética , Proteínas de Ligação a RNA/genética , Adenosina Desaminase/metabolismo , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Estabilidade de RNA/fisiologia , Proteínas de Ligação a RNA/metabolismoRESUMO
Ninety healthy and unrelated volunteers were randomly selected to study the gene frequencies of Killer-cell immunoglobulin-like receptors (KIRs) in a Chilean (Talca) population. KIR typing was resolved by PCR-single specific primer (SSP), and their gene frequencies were calculated by direct counting of the number of positive and negative loci. The KIR genotype data is publicly available in the Allele Frequencies Net Database under the name "Chile Talca KIR".