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With the largest genomic dataset to date of Bantu-speaking populations, including newly generated data of modern-day and ancient DNA from previously unsampled regions in Africa, we shed fresh light on the expansion of peoples speaking Bantu languages that started ∼4000 years ago in western Africa. We have genotyped 1,740 participants, including 1,487 Bantu speakers from 143 populations across 14 African countries, and generated whole-genome sequences from 12 Late Iron Age individuals. Our results show that Bantu speakers received significant gene-flow from local groups in regions they expanded into. We show for the first time that genetic diversity amongst Bantu-speaking populations declines with distance from western Africa, with current-day Zambia and the DRC as possible crossroads of interaction. Using spatially explicit methods and correlating genetic, linguistic and geographical data, we provide cross-disciplinary support for a serial founder migration model. Finally, we discuss the utility of our dataset as an exhaustive modern-day African comparative dataset for ancient DNA studies. These new findings and data will be important to a wide range of disciplines from science and humanities as well as to the medical sector studying human genetic variation and health in African and African-descendant populations.One-sentence summaryA comprehensive genetic analysis of the expansion of people speaking Bantu languages reveals a complex history of serial founder events, variable levels of contact with local groups, and spread-over-spread events.

Analysis of microbial data from archaeological samples is a rapidly growing field with a great potential for understanding ancient environments, lifestyles and disease spread in the past. However, high error rates have been a long-standing challenge in ancient metagenomics analysis. This is also complicated by a limited choice of ancient microbiome specific computational frameworks that meet the growing computational demands of the field. Here, we propose aMeta, an accurate ancient Metagenomic profiling workflow designed primarily to minimize the amount of false discoveries and computer memory requirements. Using simulated ancient metagenomic samples, we benchmark aMeta against a current state-of-the-art workflow, and demonstrate its superior sensitivity and specificity in both microbial detection and authentication, as well as substantially lower usage of computer memory. aMeta is implemented as a Snakemake workflow to facilitate use and reproducibility.

The southern African indigenous Khoe-San populations harbor the most divergent lineages of all living peoples. Exploring their genomes is key to understanding deep human history. We sequenced 25 full genomes from five Khoe-San populations, revealing many novel variants, that 25% of variants are unique to the Khoe-San, and that the Khoe-San group harbors the greatest level of diversity across the globe. In line with previous studies, we found several gene regions with extreme values in genome-wide scans for selection, potentially caused by natural selection in the lineage leading to Homo sapiens and more recent in time. These gene regions included immunity-, sperm-, brain-, diet-, and muscle-related genes. When accounting for recent admixture, all Khoe-San groups display genetic diversity approaching the levels in other African groups and a reduction in effective population size starting around 100,000 years ago. Hence, all human groups show a reduction in effective population size commencing around the time of the Out-of-Africa migrations, which coincides with changes in the paleoclimate records, changes that potentially impacted all humans at the time.

Each region of the world, and the human groups living in them, have unique histories of migration, genetic mixing (admixture) and adaptation that have shaped their past. While archaeology has been of extreme value in elucidating this complex, multifaceted past, the genesis of DNA studies has enriched their story, and now ancient DNA (aDNA) has helped answer even more questions surrounding our prehistory. aDNA offers a unique opportunity to access genetic variation of past populations and enables us to contextualize past populations in present-day genetic variation. By linking the past to the present in this way, we now have a deeper understanding of our prehistory, and how our genetic landscape has changed from the past to the present. However, the study of aDNA is complex and there are various factors that need to be considered to yield successful aDNA results.

Humans living in the Andes Mountains have been historically exposed to arsenic from natural sources, including drinking water. Enzymatic methylation of arsenic allows it to be excreted more efficiently by the human body. Adaptation to high-arsenic environments via enhanced methylation and excretion of arsenic was first reported in indigenous women in the Argentinean Andes, but whether adaptation to arsenic is a general phenomenon across native populations from the Andes Mountains remains unclear. Therefore, we evaluated whether adaptation to arsenic has occurred in the Bolivian Andes by studying indigenous groups who belong to the Aymara-Quechua and Uru ethnicities and have lived in the Bolivian Andes for generations. Our population genetics methods, including genome-wide selection scans based on linkage disequilibrium patterns and allele frequency differences, in combination with targeted and whole-genome sequencing and genotype-phenotype association analyses, detected signatures of positive selection near the gene encoding arsenite methyltransferase (AS3MT), the main arsenic methylating enzyme. This was among the strongest selection signals (top 0.5% signals via locus-specific branch length and extended haplotype homozygosity tests) at a genome-wide level in the Bolivian study groups. We found a large haplotype block of 676 kb in the AS3MT region and identified candidate functional variants for further analysis. Moreover, our analyses revealed associations between AS3MT variants and the fraction of mono-methylated arsenic in urine and showed that the Bolivian study groups had the highest frequency of alleles associated with more efficient arsenic metabolism reported so far. Our data support the idea that arsenic exposure has been a driver for human adaptation to tolerate arsenic through more efficient arsenic detoxification in different Andean populations.

Background Mitochondrial haplogroup assignment is an important tool for forensics and evolutionary genetics. African populations are known to display a high diversity of mitochondrial haplogroups. In this research we explored mitochondrial haplogroup assignment in African populations using commonly used genome-wide SNP arrays. Results We show that, from eight commonly used SNP arrays, two SNP arrays outperform the other arrays when it comes to the correct assignment of African mitochondrial haplogroups. One array enables the recognition of 81% of the African mitochondrial haplogroups from our compiled dataset of full mitochondrial sequences. Other SNP arrays were able to assign 4–62% of the African mitochondrial haplogroups present in our dataset. We also assessed the performance of available software for assigning mitochondrial haplogroups from SNP array data. Conclusions These results provide the first cross-checked quantification of mitochondrial haplogroup assignment performance from SNP array data. Mitochondrial haplogroup frequencies inferred from most common SNP arrays used for human population analysis should be considered with caution.

Southern African indigenous groups, traditionally hunter-gatherers (San) and herders (Khoekhoe), are commonly referred to as “Khoe-San” populations and have a long history in southern Africa. Their ancestors were largely isolated up until ∼2,000 years ago before the arrival of pastoralists and farmers in southern Africa. Assessing relationships among regional Khoe-San groups has been challenging due to admixture with immigrant populations that obscure past population affinities and gene flow among these autochthonous communities. We re-evaluate a combined genome-wide data set of previously published southern Africa Khoe-San populations in conjunction with novel data from Khoe-San individuals collected in Xade (Central Kalahari Game Reserve, Botswana) prior to their resettlement outside the reserve. After excluding regions in the genome that trace their ancestry to recent migrant groups, the genetic diversity of 20 Khoe-San groups fitted an isolation-by-distance model. Even though isolation-by-distance explained most genetic affinities between the different autochthonous groups, additional signals of contact between Khoe-San groups could be detected. For instance, we found stronger genetic affinities, than what would be explained by isolation-by-distance gene flow, between the two geographically separated Khoe-San groups, who speak branches of the Kx’a-language family (ǂHoan and Ju). We also scanned the genome-wide data for signals of adaptive gene flow from farmers/herders into Khoe-San groups and identified a number of genomic regions potentially introduced by the arrival of the new groups. This study provides a comprehensive picture of affinities among Khoe-San groups, prior to the arrival of recent migrants, and found that these affinities are primarily determined by the geographic landscape.

Ancient DNA (aDNA) has played a major role in our understanding of the past. Important advances in the sequencing and analysis of aDNA from a range of organisms have enabled a detailed understanding of processes such as past demography, introgression, domestication, adaptation and speciation. However, to date and with the notable exception of microbiomes and sediments, most aDNA studies have focused on single taxa or taxonomic groups, making the study of changes at the community level challenging. This is rather surprising because current sequencing and analytical approaches allow us to obtain and analyse aDNA from multiple source materials. When combined, these data can enable the simultaneous study of multiple taxa through space and time, and could thus provide a more comprehensive understanding of ecosystem-wide changes. It is therefore timely to develop an integrative approach to aDNA studies by combining data from multiple taxa and substrates. In this review, we discuss the various applications, associated challenges and future prospects of such an approach.

Summary Multiple lines of evidence show that modern humans interbred with archaic Denisovans. Here, we report an account of shared demographic history between Australasians and Denisovans distinctively in Island Southeast Asia. Our analyses are based on ∼2.3 million genotypes from 118 ethnic groups of the Philippines, including 25 diverse self-identified Negrito populations, along with high-coverage genomes of Australopapuans and Ayta Magbukon Negritos. We show that Ayta Magbukon possess the highest level of Denisovan ancestry in the world—∼30%–40% greater than that of Australians and Papuans—consistent with an independent admixture event into Negritos from Denisovans. Together with the recently described Homo luzonensis, we suggest that there were multiple archaic species that inhabited the Philippines prior to the arrival of modern humans and that these archaic groups may have been genetically related. Altogether, our findings unveil a complex intertwined history of modern and archaic humans in the Asia-Pacific region, where distinct Islander Denisovan populations differentially admixed with incoming Australasians across multiple locations and at various points in time., Highlights • Comprehensive analyses of archaic ancestry among 118 Philippine ethnic groups • Ayta Magbukon display ∼30%–40% greater Denisovan ancestry than Australopapuans • The model is explained by a distinct admixture event into Negritos from Denisovans • Prior to modern humans, Islander Denisovans may have been present in the Philippines, Larena et al. reveal Philippine Ayta to possess the highest level of Denisovan ancestry in the world—∼30%–40% greater than that of Australopapuans—consistent with an independent admixture event into Negritos from Denisovans. The Philippine archipelago is thus likely inhabited by multiple archaic groups prior to the arrival of modern humans.

Significance A key link to understand human history in Island Southeast Asia is the Philippine archipelago and its poorly investigated genetic diversity. We analyzed the most comprehensive set of population-genomic data for the Philippines: 1,028 individuals covering 115 indigenous communities. We demonstrate that the Philippines were populated by at least five waves of human migration. The Cordillerans migrated into the Philippines prior to the arrival of rice agriculture, where some remain as the least admixed East Asians carrying an ancestry shared by all Austronesian-speaking populations, thereby challenging an exclusive out-of-Taiwan model of joint farming–language–people dispersal. Altogether, our findings portray the Philippines as a crucial gateway, with a multilayered history, that ultimately changed the genetic landscape of the Asia-Pacific region., Island Southeast Asia has recently produced several surprises regarding human history, but the region’s complex demography remains poorly understood. Here, we report ∼2.3 million genotypes from 1,028 individuals representing 115 indigenous Philippine populations and genome-sequence data from two ∼8,000-y-old individuals from Liangdao in the Taiwan Strait. We show that the Philippine islands were populated by at least five waves of human migration: initially by Northern and Southern Negritos (distantly related to Australian and Papuan groups), followed by Manobo, Sama, Papuan, and Cordilleran-related populations. The ancestors of Cordillerans diverged from indigenous peoples of Taiwan at least ∼8,000 y ago, prior to the arrival of paddy field rice agriculture in the Philippines ∼2,500 y ago, where some of their descendants remain to be the least admixed East Asian groups carrying an ancestry shared by all Austronesian-speaking populations. These observations contradict an exclusive “out-of-Taiwan” model of farming–language–people dispersal within the last four millennia for the Philippines and Island Southeast Asia. Sama-related ethnic groups of southwestern Philippines additionally experienced some minimal South Asian gene flow starting ∼1,000 y ago. Lastly, only a few lowlanders, accounting for

Background Suicidal ideation is an important mental health issue among homeless people. Despite the fact that spirituality and religiousness (S/R) have been associated with lower levels of suicide behavior, there is little evidence on this relationship among homeless individuals. Thus, this study aims to investigate the association between S/R and suicidal ideation among homeless people living in a large Brazilian city. Methods This cross-sectional study included 456 homeless individuals living in Sao Paulo, Brazil. Logistic and linear regression models were used to determine the role of religious and spiritual beliefs (Duke Religion Index, FACIT SP-12 and Brief-RCOPE) on suicidal ideation, after adjustements. Results Most participants were male (75%) with a mean age of 44.53(SD 12.62) years. A total of 49.6% had significant depressive symptoms and the prevalence of suicidal ideation was 29.8%. In the adjusted logistic regression, higher levels of religiousness (organizational, nonorganizational and intrinsic), positive religious/spiritual coping, peace and meaning were associated with a lower suicidal ideation. The same results were found when using linear regression models. Limitations Long questionnaires can be factors of inhibition and fatigue for the participants. Suicidal ideation was based on a single question. Conclusion Our results revealed a high prevalence of suicidal ideation and depression in our sample. Religiousness and spirtuality were important factors in the life of homeless individuals, being negatively associated with suicidal ideation. These results could make healthcare professionals aware of the importance of addressing S/R issues in this vulnerable population.

Introdução: Os dispositivos intrauterinos (DIU) são excelentes métodos contraceptivos, denominados LARCs (Long-Action Reversible Contraception). O DIU de cobre é um método contraceptivo muito utilizado, com alta eficácia (índice de Pearl de 0,2‒0,4), e tem excelente custo-benefício, podendo ser obtido e inserido na rede pública de saúde. Há alguns profissionais de saúde e pessoas leigas que advogam se a nuliparidade é um fator impeditivo para o uso do DIU, por haver maior dificuldade na inserção e maior taxa de expulsão da cavidade endometrial. Objetivos: Avaliar se a nuliparidade está associada ao maior desconforto na inserção e à taxa de sucesso quando realizada ambulatorialmente. Além disso, o estudo visou analisar a taxa de satisfação e continuidade do uso dos DIU entre mulheres com e sem filhos. Pacientes e Métodos: Estudo descritivo por meio da aplicação de formulário on-line (Google Forms®), não validado e desenvolvido pelos pesquisadores. O formulário foi distribuído em grupos específicos das redes sociais e do WhatsApp®, estando disponível para respostas entre os meses de abril e maio de 2020. Só participaram do estudo mulheres que afirmaram ter mais de 18 anos e que usam ou já utilizaram DIU de cobre. Para a análise do desconforto durante a inserção foi utilizada a escala visual analógica (EVA). Os dados foram inseridos no programa Microsoft Office Excel 2016®. Para identificar a homogeneidade da amostra, foram utilizados o programa GraphPad InStat v. 3.0 para Windows 10, GraphPad Software, San Diego California USA, e o teste de Kolmogorov-Smirnov; para variáveis categóricas, foi utilizado o teste χ2 ou de Fisher; e para variáveis contínuas, o teste de Mann-Whitney ou Kruskall-Wallis. Para significância estatística dos resultados, foi adotado p0,05). Conclusões: A nuliparidade está associada ao maior desconforto durante a inserção do DIU, mas as taxas de sucesso da inserção ambulatorial são iguais entre nuligestas e mulheres com filhos. As taxas de continuidade e reações adversas são similares entre os grupos estudados. A nuliparidade não é fator impeditivo para uso do DIU.

Introdução: Há dois tipos de dispositivos intrauterinos disponíveis no Brasil: com cobre (DIU T Cobre ou Multiload) e com levonorgestrel (Mirena® ou Kyleena®). Apesar da possibilidade do longo tempo de uso, não depender da mulher para ter efeito contraceptivo e ter poucas contraindicações, deve-se levar em consideração se as usuárias desses dispositivos estão satisfeitas com o método. Objetivos: Analisar a taxa de satisfação e continuidade do uso dos dispositivos intrauterinos de cobre e com levonorgestrel; identificar os principais efeitos adversos dos dispositivos intrauterinos responsáveis pela desistência do método contraceptivo. Pacientes e Métodos: Estudo descritivo por meio da aplicação de formulário on-line (Google Forms®), não validado e desenvolvido pelos pesquisadores. O formulário foi distribuído em grupos específicos das redes sociais e do WhatsApp®, estando disponível para respostas entre abril e maio de 2020. Só participaram do estudo mulheres acima dos 18 anos e que usam ou já utilizaram dispositivos intrauterinos. Os dados foram inseridos no programa Microsoft Office Excel 2016®. Para identificar a homogeneidade da amostra, foram utilizados o programa GraphPad InStat v. 3.0 para Windows 10, GraphPad Software, San Diego California USA, e o teste de Kolmogorov-Smirnov; para variáveis categóricas, foi utilizado o teste χ2 ou de Fisher; e para variáveis contínuas, o teste de Mann-Whitney ou Kruskall-Wallis. Para significância estatística dos resultados, foi adotado p

The history of human populations in Africa is complex and includes various demographic events that influenced patterns of genetic variation across the continent. Through genetic studies of modern-day, and most recently, ancient African genetic variation, it became evident that deep African history is captured by the relationships among hunter-gatherers. Furthermore, it was shown that agriculture had a large influence on the distribution of current-day Africans. These later population movements changed the demographic face of the continent and descendants of farming groups today form the majority populations across Africa. Ancient DNA methods are continually evolving, and we see evidence of this in how research has advanced in the last decade. With the increased availability of full genomic data from diverse sets of modern-day and prehistoric Africans we now have more power to infer human demography. Future ancient DNA research promises to reveal more detailed stories of human prehistory in Africa.

The Afrikaner population of South Africa are the descendants of European colonists who started to colonize the Cape of Good Hope in the 1600’s. In the early days of the colony, mixed unions between European males and non-European females gave rise to admixed children who later became incorporated into either the Afrikaner or the “Coloured” populations of South Africa. Ancestry, social class, culture, sex ratio and geographic structure affected admixture patterns and caused different ancestry and admixture patterns in Afrikaner and Coloured populations. The Afrikaner population has a predominant European composition, whereas the Coloured population has more diverse ancestries. Genealogical records estimated the non-European contributions into the Afrikaners to 5.5%-7.2%. To investigate the genetic ancestry of the Afrikaner population today (11-13 generations after initial colonization) we genotyped ~5 million genome-wide markers in 77 Afrikaner individuals and compared their genotypes to populations across the world to determine parental source populations and admixture proportions. We found that the majority of Afrikaner ancestry (average 95.3%) came from European populations (specifically northwestern European populations), but that almost all Afrikaners had admixture from non-Europeans. The non-European admixture originated mostly from people who were brought to South Africa as slaves and, to a lesser extent, from local Khoe-San groups. Furthermore, despite a potentially small founding population, there is no sign of a recent bottleneck in the Afrikaner compared to other European populations. Admixture among diverse groups during early colonial times might have counterbalanced the effects of a founding population with a small census size.SIGNIFICANCE STATEMENTAfrikaners are a southern African ethnic group primarily descended from colonial settlers (population ~2.8–3.5 million). Genome-wide studies might offer interesting insights into their ancestry, not the least due to South Africa’s history of segregationist laws known as “apartheid”, resulting in an expectation of low levels of admixture with other groups. Originating from a small founder population, their genetic diversity is also interesting. In our genome-wide study of 77 Afrikaners we found their majority ancestry (average 95.3%) came from Europeans, but almost all Afrikaners had admixture from non-Europeans (Africans and Asians). Despite their small founding population, we found no signs of decreased genetic diversity. Admixture among diverse groups during colonial times might have counterbalanced effects of a small founding population.

Southern Africa is consistently placed as a potential region for the evolution of Homo sapiens . We present genome sequences, up to 13x coverage, from seven ancient individuals from KwaZulu-Natal, South Africa. The remains of three Stone Age hunter-gatherers (about 2000 years old) were genetically similar to current-day southern San groups, and those of four Iron Age farmers (300 to 500 years old) were genetically similar to present-day Bantu-language speakers. We estimate that all modern-day Khoe-San groups have been influenced by 9 to 30% genetic admixture from East Africans/Eurasians. Using traditional and new approaches, we estimate the first modern human population divergence time to between 350,000 and 260,000 years ago. This estimate increases the deepest divergence among modern humans, coinciding with anatomical developments of archaic humans into modern humans, as represented in the local fossil record.

Scandinavia was one of the last geographic areas in Europe to become habitable for humans after the last glaciation. However, the origin(s) of the first colonizers and their migration routes remain unclear. We sequenced the genomes, up to 57x coverage, of seven hunter-gatherers excavated across Scandinavia and dated to 9,500-6,000 years before present. Surprisingly, among the Scandinavian Mesolithic individuals, the genetic data display an east-west genetic gradient that opposes the pattern seen in other parts of Mesolithic Europe. This result suggests that Scandinavia was initially colonized following two different routes: one from the south, the other from the northeast. The latter followed the ice-free Norwegian north Atlantic coast, along which novel and advanced pressure-blade stone-tool techniques may have spread. These two groups met and mixed in Scandinavia, creating a genetically diverse population, which shows patterns of genetic adaptation to high latitude environments. These adaptations include high frequencies of low pigmentation variants and a gene-region associated with physical performance, which shows strong continuity into modern-day northern Europeans.

Arctic populations live in an environment characterized by extreme cold and the absence of plant foods for much of the year and are likely to have undergone genetic adaptations to these environmental conditions in the time they have been living there. Genome-wide selection scans based on genotype data from native Siberians have previously highlighted a 3 Mb chromosome 11 region containing 79 protein-coding genes as the strongest candidates for positive selection in Northeast Siberians. However, it was not possible to determine which of the genes might be driving the selection signal. Here, using whole-genome high-coverage sequence data, we identified the most likely causative variant as a nonsynonymous G>A transition (rs80356779; c.1436C>T [p.Pro479Leu] on the reverse strand) in CPT1A, a key regulator of mitochondrial long-chain fatty-acid oxidation. Remarkably, the derived allele is associated with hypoketotic hypoglycemia and high infant mortality yet occurs at high frequency in Canadian and Greenland Inuits and was also found at 68% frequency in our Northeast Siberian sample. We provide evidence of one of the strongest selective sweeps reported in humans; this sweep has driven this variant to high frequency in circum-Arctic populations within the last 6–23 ka despite associated deleterious consequences, possibly as a result of the selective advantage it originally provided to either a high-fat diet or a cold environment.