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Resistant hypertension (RH) is defined as uncontrolled blood pressure despite treatment with three or more antihypertensive medications, including, if tolerated, a diuretic in adequate doses. It has been widely known that race is associated with blood pressure control. However, intense debate persists as to whether this is solely explained by unadjusted socioeconomical variables or genetic variation. In this scenario, the main aim was to evaluate the association between genetic ancestry and resistant hypertension in a large sample from a multicenter trial of stage II hypertension, the ReHOT study. Samples from 1,358 patients were analyzed, of which 167 were defined as resistant hypertensive. Genetic ancestry was defined using a panel of 192 polymorphic markers. The genetic ancestry was similar in resistant (52.0% European, 36.7% African and 11.3% Amerindian) and nonresistant hypertensive patients (54.0% European, 34.4% African and 11.6% Amerindian) (p > 0.05). However, we observed a statistically suggestive association of African ancestry with resistant hypertension in brown patient group. In conclusion, increased African genetic ancestry was not associated with RH in Brazilian patients from a prospective randomized hypertension clinical trial.

Previous genetic studies have suggested that the Americas were peopled by a single founding population of Eurasian origin, but a genome-wide study of 30 Native American groups shows that Amazonian Native Americans also have a second source of ancestry that is deeply related to indigenous Australians, New Guineans and Andaman Islanders. Populating the Americas Most genetic studies have suggested that the Americas were peopled by a single founding population of Eurasian origin, but morphological studies have cast doubt on this. David Reich and colleagues analysed genome-wide data from 63 individuals from 21 Native American populations from Central and South America, and from 197 non-American populations sampled worldwide. They find evidence for a more diverse set of founding populations of the Americas than previously accepted. Some Amazonian Native Americans are partly descended from a founding population of southern origin, related to indigenous Australians, New Guineans and Andaman Islanders. This is distinct from the predominantly Eurasian ancestry of Northern and Central Native American populations. Genetic studies have consistently indicated a single common origin of Native American groups from Central and South America 1 , 2 , 3 , 4 . However, some morphological studies have suggested a more complex picture, whereby the northeast Asian affinities of present-day Native Americans contrast with a distinctive morphology seen in some of the earliest American skeletons, which share traits with present-day Australasians (indigenous groups in Australia, Melanesia, and island Southeast Asia) 5 , 6 , 7 , 8 . Here we analyse genome-wide data to show that some Amazonian Native Americans descend partly from a Native American founding population that carried ancestry more closely related to indigenous Australians, New Guineans and Andaman Islanders than to any present-day Eurasians or Native Americans. This signature is not present to the same extent, or at all, in present-day Northern and Central Americans or in a ∼12,600-year-old Clovis-associated genome, suggesting a more diverse set of founding populations of the Americas than previously accepted.

When humans moved from Asia toward the Americas over 18,000 y ago and eventually peopled the New World they encountered a new environment with extreme climate conditions and distinct dietary resources. These environmental and dietary pressures may have led to instances of genetic adaptation with the potential to influence the phenotypic variation in extant Native American populations. An example of such an event is the evolution of the fatty acid desaturases (FADS) genes, which have been claimed to harbor signals of positive selection in Inuit populations due to adaptation to the cold Greenland Arctic climate and to a protein-rich diet. Because there was evidence of intercontinental variation in this genetic region, with indications of positive selection for its variants, we decided to compare the Inuit findings with other Native American data. Here, we use several lines of evidence to show that the signal of FADS-positive selection is not restricted to the Arctic but instead is broadly observed throughout the Americas. The shared signature of selection among populations living in such a diverse range of environments is likely due to a single and strong instance of local adaptation that took place in the common ancestral population before their entrance into the New World. These first Americans peopled the whole continent and spread this adaptive variant across a diverse set of environments.

Native Americans from the Amazon, Andes, and coastal geographic regions of South America have a rich cultural heritage but are genetically understudied, therefore leading to gaps in our knowledge of their genomic architecture and demographic history. In this study, we sequence 150 genomes to high coverage combined with an additional 130 genotype array samples from Native American and mestizo populations in Peru. The majority of our samples possess greater than 90% Native American ancestry, which makes this the most extensive Native American sequencing project to date. Demographic modeling reveals that the peopling of Peru began ∼12,000 y ago, consistent with the hypothesis of the rapid peopling of the Americas and Peruvian archeological data. We find that the Native American populations possess distinct ancestral divisions, whereas the mestizo groups were admixtures of multiple Native American communities that occurred before and during the Inca Empire and Spanish rule. In addition, the mestizo communities also show Spanish introgression largely following Peruvian Independence, nearly 300 y after Spain conquered Peru. Further, we estimate migration events between Peruvian populations from all three geographic regions with the majority of between-region migration moving from the high Andes to the low-altitude Amazon and coast. As such, we present a detailed model of the evolutionary dynamics which impacted the genomes of modern-day Peruvians and a Native American ancestry dataset that will serve as a beneficial resource to addressing the underrepresentation of Native American ancestry in sequencing studies.

Historical records and genetic analyses indicate that Latin Americans trace their ancestry mainly to the intermixing (admixture) of Native Americans, Europeans and Sub-Saharan Africans. Using novel haplotype-based methods, here we infer sub-continental ancestry in over 6,500 Latin Americans and evaluate the impact of regional ancestry variation on physical appearance. We find that Native American ancestry components in Latin Americans correspond geographically to the present-day genetic structure of Native groups, and that sources of non-Native ancestry, and admixture timings, match documented migratory flows. We also detect South/East Mediterranean ancestry across Latin America, probably stemming mostly from the clandestine colonial migration of Christian converts of non-European origin (Conversos). Furthermore, we find that ancestry related to highland (Central Andean) versus lowland (Mapuche) Natives is associated with variation in facial features, particularly nose morphology, and detect significant differences in allele frequencies between these groups at loci previously associated with nose morphology in this sample. Latin Americans trace their ancestry to the admixture of Native Americans, Europeans and Sub-Saharan Africans. Here, the authors develop a novel haplotype-based approach and analyse over 6,500 Latin Americans to infer the geographically-detailed genetic structure of this population.

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 Americas 1 – 6 , while critics have argued that these botanical dispersals need not have been human mediated 7 . 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 suggested 8 – 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 Oceania 13 – 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. Genomic analyses of DNA from modern individuals show that, about 800 years ago, pre-European contact occurred between Polynesian individuals and Native American individuals from near present-day Colombia, while remote Pacific islands were still being settled.

Abstract South America is home to one of the most culturally diverse present-day native populations. However, the dispersion pattern, genetic substructure, and demographic complexity within South America are still poorly understood. Based on genome-wide data of 58 native populations, we provide a comprehensive scenario of South American indigenous groups considering the genomic, environmental, and linguistic data. Clear patterns of genetic structure were inferred among the South American natives, presenting at least four primary genetic clusters in the Amazonian and savanna regions and three clusters in the Andes and Pacific coast. We detected a cline of genetic variation along a west-east axis, contradicting a hard Andes-Amazon divide. This longitudinal genetic variation seemed to have been shaped by both serial population bottlenecks and isolation by distance. Results indicated that present-day South American substructures recapitulate ancient macroregional ancestries and western Amazonia groups show genetic evidence of cultural exchanges that led to language replacement in precontact times. Finally, demographic inferences pointed to a higher resilience of the western South American groups regarding population collapses caused by the European invasion and indicated precontact population reductions and demic expansions in South America.

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.

Genome-wide association studies (GWAS) have identified numerous genetic variants associated with Alzheimer's disease (AD), yet their effect sizes vary across populations. This variability stems from ancestry-dependent differences in the genomic regulatory architecture (GRA), which governs gene expression in a cell-type-specific manner. Notably, the influence of local ancestry on AD risk is particularly pronounced in APOE4 carriers. Here, we investigate ancestry- and cell-type-specific regulatory landscapes of AD GWAS genes using iPSC-derived neural spheroids from individuals of African, Amerindian, or European ancestry. Peripheral blood mononuclear cells (PBMCs) from AD patients and cognitively healthy controls were selected based on >85% global ancestry from a specific background. The PBMCs were reprogrammed into a total of 18 induced pluripotent stem cell (iPSC) lines, 6 from each ancestry, and differentiated into three-dimensional neural spheroids containing astrocytes, neurons, oligodendrocyte precursor cells (OPCs), and oligodendrocytes. On day 76, nuclei were isolated for multiomic profiling, including single-cell ATAC-seq, single-cell RNA-seq, and bulk Hi-C. Data were analyzed to identify ancestry-dependent GRA differences across cell types. The highest number of differentially expressed AD GWAS genes (DEAGG) was observed in astrocytes, followed by neurons, OPCs, and oligodendrocytes. Comparisons involving Amerindian ancestry samples revealed the most DEAGG across all cell types. APOE and PSEN2 were differentially expressed in both astrocytes and neurons. Additional AD-associated genes, including SORL1 and TMEM106B, were differentially expressed in multiple comparisons. Our findings underscore the critical role of ancestry in shaping the regulatory landscapes of AD-related genes, particularly in astrocytes and neurons. By expanding our understanding of ancestry-specific GRA, this study provides crucial insights into the genetic mechanisms underlying AD risk and offers a foundation for more and innovative precision medicine approaches.

Y‐chromosomal haplogroups and the Y‐SNPs defining them are relevant for the exploration of male lineages, inference of paternal ancestry, and reconstruction of migration pathways, to name a few. Currently, over 300,000 Y‐SNPs have been reported, defining 20 main haplogroups. However, ascertainment bias in the investigations has led to some haplogroups being overlooked, which hinders a representative depiction of certain populations and their migration events. For migration pattern analyses of the first settlers of the Americas, the Native American main founding lineage Q‐M3 needs to be further investigated to allow clear genetic differentiation of individuals of different ethnogeographic origins. To increase the resolution within this haplogroup, a total of 7.45 Mb of the Y chromosome of 59 admixed South Americans of haplogroup Q was targeted for sequencing using hybridization capture enrichment. Data were combined with 218 publicly available sequences of Central and South Americans of haplogroup Q. After rigorous data processing, variants not meeting the quality criteria were excluded and 4128 reliable Y‐SNPs were reported. A total of 2224 Y‐SNPs had previously unknown positions in the phylogenetic tree, and 1291 of these are novel. The phylogenetic relationships between the Y‐SNPs were established using the software SNPtotree in order to report a redesigned phylogenetic tree containing 300 branches, defined by 3400 Y‐SNPs. The new tree introduces 117 previously undescribed branches and is the most comprehensive phylogenetic tree of the Native American haplogroup Q lineages to date. The 214 sequences were assigned to 135 different low‐ to high‐resolution branches, while in the previous phylogenetic tree, only 195 sequences could be sorted into 14 low‐resolution branches with the same quality criteria. The improved genetic differentiation of subhaplogroup Q‐M3 has a great potential to resolve migration patterns of Native Americans.