While South Americans are underrepresented in human genomic diversity studies, Brazil has been a classical model for population genetics studies on admixture. We present the results of the EPIGEN Brazil Initiative, the most comprehensive up-to-date genomic analysis of any Latin-American population. A population-based genomewide analysis of 6,487 individuals was performed in the context of worldwide genomic diversity to elucidate how ancestry, kinship, and inbreeding interact in three populations with different histories from the Northeast (African ancestry: 50%), Southeast, and South (both with European ancestry >70%) of Brazil. We showed that ancestry-positive assortative mating permeated Brazilian history. We traced European ancestry in the Southeast/South to a wider European/Middle Eastern region with respect to the Northeast, where ancestry seems restricted to Iberia. By developing an approximate Bayesian computation framework, we infer more recent European immigration to the Southeast/South than to the Northeast. Also, the observed low Native-American ancestry (6-8%) was mostly introduced in different regions of Brazil soon after the European Conquest. We broadened our understanding of the African diaspora, the major destination of which was Brazil, by revealing that Brazilians display two within-Africa ancestry components: one associated with non-Bantu/western Africans (more evident in the Northeast and African Americans) and one associated with Bantu/eastern Africans (more present in the Southeast/ South). Furthermore, the whole-genome analysis of 30 individuals (42-fold deep coverage) shows that continental admixture rather than local post-Columbian history is the main and complex determinant of the individual amount of deleterious genotypes.Latin America | population genetics | Salvador SCAALA | Bambuí Cohort Study of Ageing | Pelotas Birth Cohort Study L atin Americans, who are classical models of the effects of admixture in human populations (1, 2), remain underrepresented in studies of human genomic diversity, notwithstanding recent studies (3, 4). Indeed, no large genome-wide study on admixed South Americans has been conducted so far. Brazil is the largest and most populous Latin-American country. Its over 200 million inhabitants are the product of post-Columbian admixture between Amerindians, Europeans colonizers or immigrants, and African slaves (1). Interestingly, Brazil was the destiny of nearly 40% of the African diaspora, receiving seven times more slaves than the United States (nearly 4 million vs. 600,000).Here, we present results of the EPIGEN Brazil Initiative (https:// epigen.grude.ufmg.br), the most comprehensive up-to-date genomic analysis of a Latin-American population. We genotyped nearly 2.2 million SNPs in 6,487 admixed individuals from three population-based cohorts from different regions with distinct demographic and socioeconomic backgrounds and sequenced the whole genome of 30 individuals from these populations at an To whom correspondence should be addressed. Email: edutars@ic...

The applicability of the risk index for surgical site infection of the National Nosocomial Infection Surveillance (NNIS) has been evaluated for its performance in different surgeries.In some procedures, it is necessary to include other variables to predict. Objective: to evaluate the applicability of the NNIS index for prediction of surgical site infection in orthopedic surgeries and to propose an alternative index. The study involved a historical cohort of 8236 patients who had been submitted to orthopaedic surgery. Statistical analysis was performed using multivariate logistic regression to fit the model. The incidence of infection was 1.41%. Prediction models were evaluated and compared to the NNIS index.The proposed model was not considered a good predictor of infection, despite moderately stratified orthopedic surgical patients in at least three of the four scores. The alternative model scored higher than the NNIS models in the prediction of infection. Infección de sitio quirúrgico en pacientes sometidos a cirugías ortopédicas: el índice de riesgo NNIS y la predicción de riesgo La aplicabilidad del Índice de Riesgo de Infección Quirúrgica del National NosocomialInfection Surveillance-NNIS ha sido evaluada en cuanto a su desempeño en diferentes cirugías. En algunos procedimientos es necesaria la inclusión de otras variables de predicción. El objetivo de este estudio fue evaluar la aplicabilidad del Índice NNIS para la predicción de la Infección de Sitio Quirúrgico en cirugías ortopédicas y proponer un índice alternativo. Se realizó un estudio de cohorte histórica en 8.236 pacientes sometidos a cirugías ortopédicas. Se utilizó el modelo logístico multivariado para ajustar el modelo. La incidencia de infección fue 1,41%. Modelos de predicción fueron evaluados y comparados al Índice NNIS. El modelo propuesto fue aquel que presentó mayor precisión en clasificar pacientes con y sin infección. El Índice NNIS no fue considerado un buen factor de predicción de la infección, a pesar de haber estratificado moderadamente a los pacientes quirúrgicos ortopédicos en por el menos tres de los cuatro puntajes. El modelo alternativo fue superior al modelo NNIS en la predicción de infección.

No abstract

While multiallelic copy number variation (mCNV) loci are a major component of genomic variation, quantifying the individual copy number of a locus and defining genotypes is challenging. Few methods exist to study how mCNV genetic diversity is apportioned within and between populations (i.e. to define the population genetic structure of mCNV). These inferences are critical in populations with a small effective size, such as Amerindians, that may not fit the Hardy-Weinberg model due to inbreeding, assortative mating, population subdivision, natural selection or a combination of these evolutionary factors. We propose a likelihood-based method that simultaneously infers mCNV allele frequencies and the population structure parameter , which quantifies the departure of homozygosity from the Hardy-Weinberg expectation. This method is implemented in the freely available software CNVice, which also infers individual genotypes using information from both the population and from trios, if available. We studied the population genetics of five immune-related mCNV loci associated with complex diseases (beta-defensins,, , and ) in 12 traditional Native American populations and found that the population structure parameters inferred for these mCNVs are comparable to but lower than those for single nucleotide polymorphisms studied in the same populations.

Nas últimas semanas muito tem se falado sobre coronavírus pelas mídias sociais e noticiários de todo o mundo. Como de costume, a mais nova gripe teve seu início na China e ultrapassou as fronteiras, se propagando por todo o mundo e logo tornou-se uma pandemia incontrolável e ameaçadora para mais de 7 bilhões de vidas. O que seria então esse monstro microscópico? Qual a sua origem e de onde vem seu poderio de destruição em massa? Será que o isolamento comunitário é a saída para evitar a instalação do caos generalizado? Onde estão os combatentes dessa guerra biológica? Leia esse editorial-cartilha na íntegra e descubra as respostas na visão da ciência moderna sobre esse cenário caótico em que estamos vivendo.