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...

Excess body weight leads to a variety of metabolic changes and increases the risk for cardiovascular diseases (CVD) in adulthood. The objective of this study was to investigate the presence of risk markers for CVD among Brazilian adolescents of normal weight and with excess body weight. The markers included blood pressure, C-reactive protein, homocysteine, tumor necrosis factor alpha, fibrinogen, fasting insulin and glucose, homeostasis model assessment of insulin resistance (HOMA-IR), leptin, total cholesterol, low-density lipoprotein cholesterol (LDL-c), high-density lipoprotein cholesterol (HDL-c), and triglycerides. We calculated odds ratios (OR) using logistic regression and adjusted for potential confounders such as age, sex, physical activity, and socioeconomic background. Compared with normal weight subjects, overweight/obese adolescents were more likely to have higher systolic blood pressure (OR = 3.49, p < 0.001), fasting insulin (OR = 8.03, p < 0.001), HOMA-IR (OR = 8.03, p < 0.001), leptin (OR = 5.55, p < 0.001), and LDL-c (OR = 5.50, p < 0.001) and lower serum HDL-c concentrations (OR = 2.76, p = 0.004). After adjustment for confounders, the estimates did not change substantially, except for leptin for which the risk associated with overweight increased to 11.09 (95% CI: 4.05-30.35). In conclusion, excess body weight in adolescents exhibits strong associations with several markers that are established as causes of CVD in adults. This observation stresses the importance of primary prevention and of maintaining a healthy body weight throughout adolescence to reduce the global burden of CVD.

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the South Asian subcontinent is characterized by a complex history of human migrations and population interactions. In this study, we used genome-wide data to provide novel insights on the demographic history and population relationships of six indo-european populations from the indian State of West Maharashtra. the samples correspond to two castes (Deshastha Brahmins and Kunbi Marathas) and four tribal groups (Kokana, Warli, Bhil and Pawara). We show that tribal groups have had much smaller effective population sizes than castes, and that genetic drift has had a higher impact in tribal populations. We also show clear affinities between the Bhil and Pawara tribes, and to a lesser extent, between the Warli and Kokana tribes. Our comparisons with available modern and ancient DnA datasets from South Asia indicate that the Brahmin caste has higher Ancient iranian and Steppe pastoralist contributions than the Kunbi Marathas caste. Additionally, in contrast to the two castes, tribal groups have very high Ancient Ancestral South indian (AASi) contributions. indo-european tribal groups tend to have higher Steppe contributions than Dravidian tribal groups, providing further support for the hypothesis that Steppe pastoralists were the source of Indo-European languages in South Asia, as well as europe.