RESUMO
The Neotropical region is the most diverse on the planet, largely owing to its mosaic of tropical rainforests. Multiple tectonic and climatic processes have been hypothesized to contribute to generating this diversity, including Andean orogeny, the closure of the Isthmus of Panama, the GAARlandia land bridge and historical connections among currently isolated forests. Micrathena spiders are diverse and widespread in the region, and thus a complete phylogeny of this genus allows the testing of hypotheses at multiple scales. We estimated a complete, dated phylogeny using morphological data for 117 Micrathena species and molecular data of up to five genes for a subset of 79 species. Employing eventc-based approaches and biogeographic stochastic mapping while considering phylogenetic uncertainty, we estimated ancestral distributions, the timing and direction of dispersal events and diversification rates among areas. The phylogeny is generally robust, with uncertainty in the position of some of the species lacking sequences. Micrathena started diversifying around 25 Ma. Andean cloud forests show the highest in-situ speciation, while the Amazon is the major dispersal source for adjacent areas. The Dry Diagonal generated few species and is a sink of diversity. Species exchange between Central and South America involved approximately 23 dispersal events and started ~20 Ma, which is consistent with a Miocene age for the Isthmus of Panama closure. We inferred four dispersal events from Central America to the Antilles in the last 20 Myr, indicating the spiders did not reach the islands through the GAARlandia land bridge. We identified important species exchange routes among the Amazon, Andean cloud forests and Atlantic forests during the Plio-Pleistocene. Sampling all species of the genus was fundamental to the conclusions above, especially in identifying the Andean forests as the area that generated the majority of species. This highlights the importance of complete taxonomic sampling in biogeographic studies.
RESUMO
During the colonial period in South America, many autochthonous populations were affected by relocation by European missionary reductions and other factors that impacted and reconfigured their genetic makeup. Presently, the descendants of some "reduced" and other isolated groups are distributed in the Amazonian areas of Peru, Bolivia, and Brazil, and among them, speakers of Takanan and Panoan languages. Based on linguistics, these peoples should be closely related, but so far no DNA comparison studies have been conducted to corroborate a genetic relationship. To clarify these questions, we used a set of 15 short tandem repeats of the non-recombining part of the Y-chromosome (Y-STRs) and mitochondrial DNA (mtDNA) control region sequence data. Paternal line comparisons showed the Takanan-speaking peoples from Peru and Bolivia descended from recent common ancestors; one group was related to Arawakan, Jivaroan, and Cocama and the other to Panoan speakers, consistent with linguistics. Also, a genetic affinity for maternal lines was observed between some Takanan speakers and individuals who spoke different Amazonian languages. Our results supported a shared ancestry of Takanan, Panoan, Cocama, and Jivaroan-speaking communities who appeared to be related to each other and came likely from an early Arawak expansion in the western Amazonia of South America.
Assuntos
DNA Mitocondrial , Genética Populacional , Humanos , Bolívia , Peru , Haplótipos , Brasil , DNA Mitocondrial/genética , Cromossomos Humanos Y/genética , Variação GenéticaRESUMO
Hybridization is known to be part of many species' evolutionary history. Sea turtles have a fascinating hybridization system in which species separated by as much as 43 million years are still capable of hybridizing. Indeed, the largest nesting populations in Brazil of loggerheads (Caretta caretta) and hawksbills (Eretmochelys imbricata) have a high incidence of hybrids between these two species. A third species, olive ridleys (Lepidochelys olivacea), is also known to hybridize although at a smaller scale. Here, we used restriction site-associated DNA sequencing (RAD-Seq) markers, mitogenomes, and satellite-telemetry to investigate the patterns of hybridization and introgression in the Brazilian sea turtle population and their relationship with the migratory behaviours between feeding and nesting aggregations. We also explicitly test if the mixing of two divergent genomes in sea turtle hybrids causes mitochondrial paternal leakage. We developed a new species-specific PCR-assay capable of detecting mitochondrial DNA (mtDNA) inheritance from both parental species and performed ultra-deep sequencing to estimate the abundance of each mtDNA type. Our results show that all adult hybrids are first generation (F1) and most display a loggerhead migratory behaviour. We detected paternal leakage in F1 hybrids and different proportions of mitochondria from maternal and paternal species. Although previous studies showed no significant fitness decrease in hatchlings, our results support genetically-related hybrid breakdown possibly caused by cytonuclear incompatibility. Further research on hybrids from other populations in addition to Brazil and between different species will show if backcross inviability and mitochondrial paternal leakage is observed across sea turtle species.
Assuntos
DNA Mitocondrial , Tartarugas , Animais , DNA Mitocondrial/genética , Tartarugas/genética , Mitocôndrias/genética , Evolução Biológica , Reação em Cadeia da PolimeraseRESUMO
Prolactin (PRL) is a pleiotropic neurohormone secreted by the mammalian pituitary gland into the blood, thus reaching many tissues and organs beyond the brain. PRL binds to its receptor, PRLR, eliciting a molecular signaling cascade. This system modulates essential mammalian behaviors and promotes notable modifications in the reproductive female tissues and organs. Here, we explore how the intracellular domain of PRLR (PRLR-ICD) modulates the expression of the PRLR gene. Despite differences in the reproductive strategies between eutherian and metatherian mammals, there is no clear distinction between PRLR-ICD functional motifs. However, we found selection signatures that showed differences between groups, with many conserved functional elements strongly maintained through purifying selection across the class Mammalia. We observed a few residues under relaxed selection, the levels of which were more pronounced in Eutheria and particularly striking in primates (Simiiformes), which could represent a pre-adaptive genetic element protected from purifying selection. Alternative, new motifs, such as YLDP (318-321) and others with residues Y283 and Y290, may already be functional. These motifs would have been co-opted in primates as part of a complex genetic repertoire related to some derived adaptive phenotypes, but these changes would have no impact on the primordial functions that characterize the mammals as a whole and that are related to the PRL-PRLR system.
Assuntos
Prolactina , Receptores da Prolactina , Animais , Evolução Molecular , Feminino , Mamíferos/genética , Mamíferos/metabolismo , Hipófise/metabolismo , Prolactina/metabolismo , Receptores da Prolactina/genética , Receptores da Prolactina/metabolismoRESUMO
BACKGROUND: According to history, in the pre-Hispanic period, during the conquest and Inka expansion in Ecuador, many Andean families of the Cañar region would have been displaced to several places of Tawantinsuyu, including Kañaris, a Quechua-speaking community located at the highlands of the Province of Ferreñafe, Lambayeque (Peru). Other families were probably taken from the Central Andes to a place close to Kañaris, named Inkawasi. Evidence of this migration comes from the presence near the Kañaris-Inkawasi communities of a village, a former Inka camp, which persists until the present day. This scenario could explain these toponyms, but it is still controversial. To clarify this historical question, the study presented here focused on the inference of the genetic relationship between 'Cañaris' populations, particularly of Cañar and Ferreñafe, compared to other highland populations. We analysed native patrilineal Y chromosome haplotypes composed of 15 short tandem repeats, a set of SNPs, and maternal mitochondrial DNA haplotypes of control region sequences. RESULTS: After the genetic comparisons of local populations-three from Ecuador and seven from Peru-, Y chromosome analyses (n = 376) indicated that individuals from the Cañar region do not share Y haplotypes with the Kañaris, or even with those of the Inkawasi. However, some Y haplotypes of Ecuadorian 'Cañaris' were associated with haplotypes of the Peruvian populations of Cajamarca, Chivay (Arequipa), Cusco and Lake Titicaca, an observation that is congruent with colonial records. Within the Kañaris and Inkawasi communities there are at least five clans in which several individuals share haplotypes, indicating that they have recent common ancestors. Despite their relative isolation, most individuals of both communities are related to those of the Cajamarca and Chachapoyas in Peru, consistent with the spoken Quechua and their geographic proximity. With respect to mitochondrial DNA haplotypes (n = 379), with the exception of a shared haplotype of the D1 lineage between the Cañar and Kañaris, there are no genetic affinities. CONCLUSION: Although there is no close genetic relationship between the Peruvian Kañaris (including Inkawasi) and Ecuadorian Cañar populations, our results showed some congruence with historical records.
Assuntos
Cromossomos Humanos Y , Indígenas Sul-Americanos , DNA Mitocondrial/genética , Equador , Marcadores Genéticos , Variação Genética , Genética Populacional , Haplótipos , Humanos , Indígenas Sul-Americanos/genética , PeruRESUMO
We review studies from our laboratories using different molecular tools to characterize the Amerindian, European and African ancestry of Brazilians. Initially we used uniparental DNA markers to investigate the contribution of distinct Y chromosome and mitochondrial DNA lineages to present-day populations. High levels of genetic admixture and strong directional mating between European males and Amerindian and African females were unraveled. We next analyzed different types of biparental autosomal polymorphisms. Especially useful was a set of 40 insertion-deletion polymorphisms (indels) that when studied worldwide proved exquisitely sensitive in discriminating between Amerindians, Europeans and Sub-Saharan Africans. When applied to the study of Brazilians these markers confirmed extensive genomic admixture. We then studied ancestry differences in different regions by statistically controlling them to eliminate color considerations. The European ancestry was predominant in all regions studied, with proportions ranging from 60.6% in the Northeast to 77.7% in the South. We propose that the immigration of 6 million Europeans to Brazil in the 19th and 20th centuries is in large part responsible for dissipating previous ancestry dissimilarities that reflected region-specific population histories. Brazilians should be assessed individually, as 210 million human beings, and not as members of specific regions or color groups.
Assuntos
População Negra , População Branca , População Negra/genética , Brasil , DNA Mitocondrial/genética , Feminino , Marcadores Genéticos , Variação Genética , Humanos , Masculino , População Branca/genéticaRESUMO
The central Andean rainforests and the Atlantic Forest are two similar biomes that are fully isolated by xerophytic and open-vegetation regions (the Chaco and Cerrado, respectively). Even though there is evidence suggesting that these rainforests have been connected in the past, their dynamics of connection, the geographic areas that bridged these regions, and the biological processes that have promoted diversification between them remain to be studied. In this research, we used three passerine species (Poecilotriccus plumbeiceps, Phylloscartes ventralis and Cacicus chrysopterus) as models to address whether the Andean and the Atlantic forests have acted as a refugia system (macrorefugia), and to evaluate biogeographic hypotheses of diversification and connection between them. In order to achieve these goals, we performed traditional phylogeographic analyses and compared alternative biogeographic scenarios by using Approximate Bayesian Computation. Additionally, we performed morphological analyses to evaluate phenotypic divergence between these regions. Our findings support that both rainforest regions acted as refugia, but that the impact of their isolation was stronger on the genetic than on the morphologic characters. Our results provided evidence that both geographic isolation as well as ecological factors have modeled the external traits of forest organisms in the region. Regarding the connection routes between the Andes and the Atlantic Forest, the genetic data rejected the hypothesis of a Chaco connection in the tested species, providing evidence for a connection through the Cerrado or through the transition between the Cerrado and Chaco, in a process that could have started as early as the Late Miocene.
Assuntos
Evolução Biológica , Florestas , Variação Genética , Passeriformes/anatomia & histologia , Passeriformes/genética , Animais , Teorema de Bayes , Ecossistema , Genética Populacional , Filogenia , Filogeografia , Especificidade da EspécieRESUMO
The Brazilian Atlantic Forest harbors high levels of anuran diversity and endemism, including several taxa restricted to small geographic ranges. Here, we provide a multilocus phylogeny for Paratelmatobiinae, a leptodactylid subfamily composed of small-ranged species distributed in the Brazilian Atlantic Forest and in the campo rupestre ecosystem. We performed Bayesian inference and maximum likelihood analyses using three mitochondrial and five nuclear markers, and a matrix comprising a broad taxonomic sampling. We then delimitated independently evolving lineages within the group. We recovered Paratelmatobiinae and each of its four genera as monophyletic and robustly supported. Five putatively new species included in our analyses were unambiguously supported in the phylogenetic trees and delimitation analyses. We also recovered other deeply divergent and geographically structured lineages within the four genera of Paratelmatobiinae. Our estimation of divergence times indicates that diversification in the subfamily began in the Eocene and continued until the Pleistocene. We discuss possible scenarios of diversification for the four genera of Paratelmatobiinae, and outline the implications of our findings for taxonomy and conservation.
Assuntos
Anuros/classificação , Biodiversidade , Florestas , Filogenia , Animais , Teorema de Bayes , Brasil , Calibragem , Núcleo Celular/genética , Consenso , DNA Mitocondrial/genética , Geografia , Especificidade da Espécie , Fatores de TempoRESUMO
An extremely high incidence of hybridization among sea turtles is found along the Brazilian coast. This atypical phenomenon and its impact on sea turtle conservation can be elucidated through research focused on the evolutionary history of sea turtles. We assessed high-quality multilocus haplotypes of 143 samples of the 5 species of sea turtles that occur along the Brazilian coast to investigate the hybridization process and the population structure of hawksbill (Eretmochelys imbricata) and loggerhead turtles (Caretta caretta). The multilocus data were initially used to characterize interspecific hybrids. Introgression (F2 hybrids) was only confirmed in hatchlings of F1 hybrid females (hawksbill × loggerhead), indicating that introgression was either previously overestimated and F2 hybrids may not survive to adulthood, or the first-generation hybrid females nesting in Brazil were born as recent as few decades ago. Phylogenetic analyses using nuclear markers recovered the mtDNA-based Indo-Pacific and Atlantic lineages for hawksbill turtles, demonstrating a deep genetic divergence dating from the early Pliocene. In addition, loggerhead turtles that share a common feeding area and belong to distinct Indo-Pacific and Atlantic mtDNA clades present no clear genetic differentiation at the nuclear level. Finally, our results indicate that hawksbill and loggerhead rookeries along the Brazilian coast are likely connected by male-mediated gene flow.
Assuntos
Genética Populacional , Hibridização Genética , Tartarugas/classificação , Tartarugas/genética , Animais , Brasil , Marcadores Genéticos , Variação Genética , Tipagem de Sequências Multilocus , FilogeniaRESUMO
The Florida manatee (Trichechus manatus latirostris) is an endangered subspecies of the West Indian manatee (T. manatus), which inhabits inland and marine waters of southeastern United States. In this study, we assembled the mitochondrial genome (mtDNA) of the Florida manatee from whole genome shotgun reads. As a result, we show that the currently annotated T. manatus mtDNA belongs to a different species, the Amazonian manatee (T. inunguis). The newly assembled Florida manatee mtDNA is 16,881 bp in length, with 13 protein-coding genes, two ribosomal RNAs (rRNAs), 22 transfer RNAs (tRNAs) and one non-coding control region (D-loop). Phylogenetic analysis based on the control region indicates the newly assembled mtDNA is haplotype A01, characteristic of T. m. latirostris, while the current mtDNA associated with the Florida manatee genome assembly has a Ti02 haplotype that is found in Amazonian manatees and hybrids.
RESUMO
The hawksbill turtle is a broadly distributed, highly migratory and critically endangered sea turtle species. The paucity of studies restricts the comprehension of its behavior and life history. In this work, we performed a global phylogeographic analysis using a compilation of previously published mitochondrial haplotype data to understand the dynamics and diversity of hawksbill populations worldwide. Our results revealed a complex demographic pattern associated to hawksbill phylogeography since the Pliocene. Isolation by distance is not enough to explain distinct demographic units of hawksbill turtles, which are also influenced by other factors as oceanic currents, coral reef distribution and nesting timing. The foraging aggregations are typically mixed stocks of individuals originating from multiple nesting areas, but there is also a trend of foragers coming from nearby natal beaches. Phylogenetic analysis indicates two highly divergent major lineages split between Atlantic and Indo-Pacific rookeries, but there is also a more recent Atlantic Ocean colonization from the Indo-Pacific Ocean. Long-distance dispersal events are likely responsible for homogenization between distant populations within oceans. Our findings provided new insights about population connectivity, identified gaps that should be prioritized in future research and highlighted the need for international efforts aiming at hawksbill's conservation.
RESUMO
We evaluated whether the Andean and the Atlantic forests acted as refugia during the Quaternary, and tested biogeographic hypotheses about the regions involved in the connectivity between those biomes (through the Chaco or the Cerrado). To achieve these goals we selected the Buff-browed Foliage-gleaner Syndactyla rufosuperciliata (Aves, Furnariidae) as a study system, a taxon distributed between the Andean and Atlantic forest. We first explored the historical connectivity between regions through niche modeling. We subsequently used DNA sequences (nâ¯=â¯71 individuals) and genomic analyses (ddRADseq, nâ¯=â¯33 individuals) to evaluate population genetic structure and gene flow within this species. Finally, we performed population model selection using Approximate Bayesian Computation. Our findings indicate that the Andean and the Atlantic forests acted as refugia, and that the populations of the focal species from both regions contacted through the Cerrado region, thus suggesting that the historical dynamics of Andean and Atlantic forests are important for the evolution of forest birds in the region. The results are in agreement with studies of other organisms and may indicate a more general pattern of connectivity among biomes in the Neotropics. Finally, we recommend recognizing both the Andean and the Altantic forests lineages of S. rufosuperciliata as independent species.
Assuntos
Ecossistema , Florestas , Passeriformes/classificação , Filogeografia , Animais , Teorema de Bayes , Fluxo Gênico , Variação Genética , Genética Populacional , Passeriformes/genética , Filogenia , Densidade Demográfica , Análise de Sequência de DNARESUMO
The West Indian (Trichechus manatus) and Amazonian (T. inunguis) manatees have a sympatric occurrence at the mouth of the Amazon River. A result of this interspecific encounter is the occurrence of hybrids, which are frequently found along the coasts of Amapá state in Brazil, French Guiana and Guyana. Here we present new genetic evidence indicating the occurrence of a hybrid swarm along the Guianas Shield coastline, which is an interspecific hybrid zone that also separates T. manatus populations located east (Brazil) and west (Caribbean, Gulf of Mexico, Florida and Antilles). In addition, we suggest that this hybrid population occupies a peculiar mangrove-rich environment under strong influence of the Amazon River plume, which requires an independent management and should be considered a special conservation area.
Assuntos
Variação Genética/genética , Hibridização Genética , Especificidade da Espécie , Trichechus inunguis/genética , Trichechus manatus/genética , Animais , Teorema de Bayes , Brasil , Região do Caribe , Guiana , Filogenia , Dinâmica Populacional , Rios , Trichechus inunguis/fisiologia , Trichechus manatus/fisiologiaRESUMO
This study focuses on the descendants of the royal Inka family. The Inkas ruled Tawantinsuyu, the largest pre-Columbian empire in South America, which extended from southern Colombia to central Chile. The origin of the royal Inkas is currently unknown. While the mummies of the Inka rulers could have been informative, most were destroyed by Spaniards and the few remaining disappeared without a trace. Moreover, no genetic studies have been conducted on present-day descendants of the Inka rulers. In the present study, we analysed uniparental DNA markers in 18 individuals predominantly from the districts of San Sebastian and San Jerónimo in Cusco (Peru), who belong to 12 families of putative patrilineal descent of Inka rulers, according to documented registries. We used single-nucleotide polymorphisms and short tandem repeat (STR) markers of the Y chromosome (Y-STRs), as well as mitochondrial DNA D-loop sequences, to investigate the paternal and maternal descent of the 18 alleged Inka descendants. Two Q-M3* Y-STR clusters descending from different male founders were identified. The first cluster, named AWKI-1, was associated with five families (eight individuals). By contrast, the second cluster, named AWKI-2, was represented by a single individual; AWKI-2 was part of the Q-Z19483 sub-lineage that was likely associated with a recent male expansion in the Andes, which probably occurred during the Late Intermediate Period (1000-1450 AD), overlapping the Inka period. Concerning the maternal descent, different mtDNA lineages associated with each family were identified, suggesting a high maternal gene flow among Andean populations, probably due to changes in the last 1000 years.
Assuntos
Cromossomos Humanos Y/genética , Indígenas Sul-Americanos/genética , Repetições de Microssatélites , Polimorfismo de Nucleotídeo Único , Feminino , Humanos , Masculino , PeruRESUMO
The central Andean rainforests and the Atlantic Forest are separated by the Chaco and the Cerrado domains. Despite this isolation, diverse evidence suggests that these rainforests have been connected in the past. However, little is known about the timing and geographic positions of these connections, as well as their effects on diversification of species. In this study, we used the Black-goggled Tanager (Trichothraupis melanops, Thraupidae) as a model to study whether the Andean and the Atlantic forests have acted as a refugia system, and to evaluate biogeographic hypotheses of diversification and connection between these rainforests. We compared alternative biogeographic scenarios by using Approximate Bayesian Computation (ABC), modeled range shifts across time, and assessed niche divergence between regions. The results indicated that the major phylogeographic gap within T. melanops is located between these rainforests. The ABC analysis supported peripatric diversification, with initial dispersal from the Atlantic Forest to the Andes during the Mid-Pleistocene. Also, the results supported an Andean-Atlantic forests connection through the current Cerrado-Chaco transition, linking the southern Atlantic Forest with the central Andes. Our findings, taken together with other studies, support that the connection between these biomes has been recurrent, and that has occurred mostly through the Cerrado and/or the Cerrado-Chaco transition. The data also support that the connection dynamic has played an important role in the biological diversification, by promoting peripatric divergence in some forest taxa restricted to both biomes.
Assuntos
Distribuição Animal/fisiologia , Biodiversidade , Florestas , Passeriformes/fisiologia , Animais , Teorema de Bayes , Genética Populacional , Modelos Teóricos , Paleontologia , Filogenia , Filogeografia , Especificidade da EspécieRESUMO
Amazon parrots are long-lived birds with highly developed cognitive skills, including vocal learning. Several parrot mitogenomes have been sequenced, but important aspects of their organization and evolution are not fully understood or have limited experimental support. The main aim of the present study was to describe the mitogenome of the blue-fronted Amazon, Amazona aestiva, and compare it to other mitogenomes from the genus Amazona and the order Psittaciformes. We observed that mitogenomes are highly conserved among Amazon parrots, and a detailed analysis of their duplicated control regions revealed conserved blocks. Population level analyses indicated that the specimen analyzed here seems to be close to A. aestiva individuals from Bahia state. Evolutionary relationships of 41 Psittaciformes species and three outgroups were inferred by BEAST. All relationships were retrieved with high support.
RESUMO
The Atlantic Forest is separated from the Andean tropical forest by dry and open vegetation biomes (Chaco and Cerrado). Despite this isolation, both rainforests share closely related lineages, which suggest a past connection. This connection could have been important for forest taxa evolution. In this study, we used the Saffron-billed Sparrow (Arremon flavirostris) as a model to evaluate whether the Andean and the Atlantic forests act as a refugia system, as well as to test for a history of biogeographic connection between them. In addition, we evaluated the molecular systematic of intraspecific lineages of the studied species. We modeled the current and past distribution of A. flavirostris, performed phylogeographic analyses based on mitochondrial and nuclear genes, and used Approximate Bayesian Computation (ABC) analyses to test for biogeographic scenarios. The major phylogeographic disjunction within A. flavirostris was found between the Andean and the Atlantic forests, with a divergence that occurred during the Mid-Pleistocene. Our paleodistribution models indicated a connection between these forest domains in different periods and through both the Chaco and Cerrado. Additionally, the phylogeographic and ABC analyses supported that the Cerrado was the main route of connection between these rainforests, but without giving decisive evidence against a Chaco connection. Our study with A. flavirostris suggest that the biodiversity of the Andean and of the Atlantic forests could have been impacted (and perhaps enriched?) by cycles of connections through the Cerrado and Chaco. This recurrent cycle of connection between the Andean and the Atlantic Forest could have been important for the evolution of Neotropical forest taxa. In addition, we discussed taxonomic implications of the results and proposed to split the studied taxon into two full species.
Assuntos
Biodiversidade , Florestas , Passeriformes/classificação , Filogeografia , Animais , Teorema de Bayes , Brasil , Variação Genética , Genética Populacional , Modelos Teóricos , Passeriformes/genética , Filogenia , Floresta Úmida , Fatores de TempoRESUMO
The giant anteater (Myrmecophaga tridactyla, Pilosa, Linnaeus 1758) belongs to the mammalian order Pilosa and presents a large distribution along South America, occupying a great variety of habitats. It is listed in the IUCN Red List of threatened species as Vulnerable. Despite threatened, there is a lack of studies regarding its genetic variability. The aim of this study was to examine the genetic diversity and patterns of genetic structure within remaining populations. We analyzed 77 individuals from seven different populations distributed in four biomes across Brazil: Cerrado, Pantanal, Atlantic Forest and Amazon Forest. We sequenced two mitochondrial markers (control region and Cyt-b) and two nuclear markers (AMELY and RAG2). We found high genetic diversity within subpopulations from National Parks of Serra da Canastra and Emas, both within the Cerrado biome, with signs of population expansion. Besides, we found a notable population structure between populations from the Cerrado/Pantanal and Amazon Forest biomes. This data is a major contribution to the knowledge of the evolutionary history of the species and to future management actions concerning its conservation.
RESUMO
This study focuses on the genetic history of the Quechua-Lamistas, inhabitants of the Lamas Province in the San Martin Department, Peru, who speak their own distinct variety of the Quechua family of languages. It has been suggested that different pre-Columbian ethnic groups from the Peruvian Amazonia, like the Motilones or "shaven heads", assimilated the Quechua language and then formed the current native population of Lamas. However, many Quechua-Lamistas claim to be direct descendants of the Chankas, a famous pre-Columbian indigenous group that escaped from Inca rule in the Andes. To investigate the Quechua-Lamistas and Chankas' ancestries, we compared uniparental genetic profiles (17 STRs of Q-M3 Y-chromosome and mtDNA complete control region haplotypes) among autochthonous Amazonian and Andean populations from Peru, Bolivia and Ecuador. The phylogeographic and population genetic analyses indicate a fairly heterogeneous ancestry for the Quechua-Lamistas, while they are closely related to their neighbours who speak Amazonian languages, presenting no direct relationships with populations from the region where the ancient Chankas lived. On the other hand, the genetic profiles of self-identified Chanka descendants living in Andahuaylas (located in the Apurimac Department, Peru, in the Central Andes) were closely related to those living in Huancavelica and the assumed Chanka Confederation area before the Inca expansion.
Assuntos
Cromossomos Humanos Y/genética , DNA Mitocondrial/genética , Genética Populacional , Indígenas Sul-Americanos/genética , Bolívia , Equador , Haplótipos , Humanos , Masculino , Peru , Análise EspacialRESUMO
Many single-nucleotide polymorphisms (SNPs) in the non-recombining region of the human Y chromosome have been described in the last decade. High-coverage sequencing has helped to characterize new SNPs, which has in turn increased the level of detail in paternal phylogenies. However, these paternal lineages still provide insufficient information on population history and demography, especially for Native Americans. The present study aimed to identify informative paternal sublineages derived from the main founder lineage of the Americas-haplogroup Q-L54-in a sample of 1841 native South Americans. For this purpose, we used a Y-chromosomal genotyping multiplex platform and conventional genotyping methods to validate 34 new SNPs that were identified in the present study by sequencing, together with many Y-SNPs previously described in the literature. We updated the haplogroup Q phylogeny and identified two new Q-M3 and three new Q-L54*(xM3) sublineages defined by five informative SNPs, designated SA04, SA05, SA02, SA03 and SA29. Within the Q-M3, sublineage Q-SA04 was mostly found in individuals from ethnic groups belonging to the Tukanoan linguistic family in the northwest Amazon, whereas sublineage Q-SA05 was found in Peruvian and Bolivian Amazon ethnic groups. Within Q-L54*, the derived sublineages Q-SA03 and Q-SA02 were exclusively found among Coyaima individuals (Cariban linguistic family) from Colombia, while Q-SA29 was found only in Maxacali individuals (Jean linguistic family) from southeast Brazil. Furthermore, we validated the usefulness of several published SNPs among indigenous South Americans. This new Y chromosome haplogroup Q phylogeny offers an informative paternal genealogy to investigate the pre-Columbian history of South America.Journal of Human Genetics advance online publication, 31 March 2016; doi:10.1038/jhg.2016.26.