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More globally diverse perspectives are needed in genomic studies and precision medicine practices on non-Europeans. Here, we illustrate this by discussing the distribution of clinically actionable genetic variants involved in drug response in Andean highlanders and Amazonians, considering their environment, history, genetic structure, and historical biases in the perception of biological diversity of Native Americans.
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Western South America was one of the worldwide cradles of civilization. The well-known Inca Empire was the tip of the iceberg of an evolutionary process that started 11,000 to 14,000 years ago. Genetic data from 18 Peruvian populations reveal the following: 1) The between-population homogenization of the central southern Andes and its differentiation with respect to Amazonian populations of similar latitudes do not extend northward. Instead, longitudinal gene flow between the northern coast of Peru, Andes, and Amazonia accompanied cultural and socioeconomic interactions revealed by archeology. This pattern recapitulates the environmental and cultural differentiation between the fertile north, where altitudes are lower, and the arid south, where the Andes are higher, acting as a genetic barrier between the sharply different environments of the Andes and Amazonia. 2) The genetic homogenization between the populations of the arid Andes is not only due to migrations during the Inca Empire or the subsequent colonial period. It started at least during the earlier expansion of the Wari Empire (600 to 1,000 years before present). 3) This demographic history allowed for cases of positive natural selection in the high and arid Andes vs. the low Amazon tropical forest: in the Andes, a putative enhancer in HAND2-AS1 (heart and neural crest derivatives expressed 2 antisense RNA1, a noncoding gene related to cardiovascular function) and rs269868-C/Ser1067 in DUOX2 (dual oxidase 2, related to thyroid function and innate immunity) genes and, in the Amazon, the gene encoding for the CD45 protein, essential for antigen recognition by T and B lymphocytes in viral-host interaction.
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Adaptação Fisiológica/genética , Indígenas Sul-Americanos/genética , Altitude , Civilização , Clima , Oxidases Duais/genética , Fluxo Gênico , Frequência do Gene , Genética Populacional , Humanos , Antígenos Comuns de Leucócito/genética , Peru/etnologia , Polimorfismo de Nucleotídeo Único , RNA Longo não Codificante/genética , Floresta Úmida , Seleção Genética , Fatores Socioeconômicos , Proteínas com Domínio T/genéticaRESUMO
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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Using smartphones during a task that requires an upright posture can be detrimental for the overall motor performance. The aim of this study was to determine the risks of accidents caused by the use of smartphones by pedestrians while walking in a controlled (laboratory) and a non-controlled (public street) environment. Two hundred and one participants, 100 men and 101 women, all young adults, were submitted to walking activities while texting messages and talking on the phone. The risk of accident was measured by the time and the number of steps necessary to walk a 20 ft distance. Assessments were performed with no external distractors (laboratory) and on a public street with vehicles, pedestrians, lights, and noises. Multivariate analysis of variance tests provided the main effect of task (using × not using smartphone), environment (laboratory × street), sex (men × women), and interactions. Significance was set at 5%. The results showed that using a smartphone while walking demanded a greater number of steps and time to perform the task (main effect of task: 0.84; p = 0.001). The risk of accident was higher on the streets where, due to traffic hazards, pedestrians performed the task faster and with a lower number of steps (the main effect of environment: 0.82; p = 0.001). There was no difference of risks between men and women (main effect of sex: 0.01; p = 0.225), whether in the laboratory or on the street (main effect of sex × environment: 0.01; p = 0.905). The task × environment interaction showed that using a smartphone on the street potentiates risks of accidents of pedestrians (main effect of task × environment: 0.41; p = 0.001). In conclusion, using a smartphone while walking can be risky for pedestrians, especially in a traffic environment. People should avoid using their smartphone while crossing streets.
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Pedestres , Acidentes de Trânsito , Atenção , Feminino , Humanos , Masculino , Segurança , Smartphone , Caminhada , Adulto JovemRESUMO
Jubaea chilensis (Molina) Baill., also named Chilean palm, is an endemic species found in the coastal area of Mediterranean sclerophyllous forest in Chile. It has a highly restricted and fragmented distribution along the coast, being under intense exploitation and anthropogenic impact. Based on 1038 SNP markers, we evaluated the genetic diversity and population structure among six J. chilensis natural groups encompassing 96% of the species distribution. We observed low levels of genetic diversity, a deficit of heterozygotes (mean HE = 0.024; HO = 0.014), and high levels of inbreeding (mean FIS = 0.424). The fixation index (FST) and Nei's genetic distance pairwise comparisons indicated low to moderate structuring among populations. There was no evidence of isolation by distance (r = -0.214, p = 0.799). In the cluster analysis, we observed a closer relationship among Culimo, Cocalán, and Candelaria populations. Migration rates among populations were low, except for some populations with moderate values. The K value that best represented the spatial distribution of genetic diversity was ∆K = 3. Habitat fragmentation, deterioration of the sclerophyllous forest, lack of long-distance dispersers, and a natural regeneration deficit may have driven inbreeding and low levels of genetic diversity in the palm groves of J. chilensis. Although extant populations are not at imminent risk of extinction, the rate of inbreeding could increase and migration could decrease if the effects of climate change and human impact become more acute.
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The effects of laser etching, decontamination, and storage treatments on dentin components were studied using Fourier transform (FT)-Raman spectroscopy. Thirty bovine incisors were prepared to expose the dentin surface and then divided in two main groups based upon the decontamination process and storage procedure: autoclaved (group A, n=15) or stored in thymol aqueous solution (group B, n=15). The surfaces of the dentin slices were schematically divided into four areas, with each one corresponding to a treatment subgroup. The specimens were either etched with phosphoric acid (control subgroup) or irradiated with erbium-doped yttrium-aluminum-garnet (Er:YAG) laser (subgroups: I-80 mJ, II-120 mJ, and III-180 mJ, and total energy of 12 J). Samples were analyzed by FT-Raman spectroscopy; we collected three spectra for each area (before and after treatment). The integrated areas of five Raman peaks were calculated to yield average spectra. The areas of the peaks associated with phosphate content (P<0.001), type I collagen, and organic C-H bonds (P<0.05) were reduced significantly in group A (control). Analyses of samples irradiated with reduced laser energies did not show significant changes in the dentin components. These results suggest that thymol storage treatment is advised for in vitro study; furthermore, 12 J of Er:YAG laser energy does not affect dentin components.
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Dentina/química , Dentina/efeitos da radiação , Lasers de Estado Sólido , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise Espectral Raman/métodos , Animais , Bovinos , Relação Dose-Resposta à Radiação , Técnicas In Vitro , Incisivo/química , Incisivo/efeitos da radiação , Doses de RadiaçãoRESUMO
Humans fundamentally affect dispersal, directly by transporting individuals and indirectly by altering landscapes and natural vectors. This human-mediated dispersal (HMD) modifies long-distance dispersal, changes dispersal paths, and overall benefits certain species or genotypes while disadvantaging others. HMD is leading to radical changes in the structure and functioning of spatial networks, which are likely to intensify as human activities increase in scope and extent. Here, we provide an overview to guide research into HMD and the resulting rewiring of spatial networks, making predictions about the ecological and evolutionary consequences and how these vary according to spatial scale and the traits of species. Future research should consider HMD holistically, assessing the range of direct and indirect processes to understand the complex impacts on eco-evolutionary dynamics.