Genomic history of coastal societies from eastern South America.

Sambaqui (shellmound) societies are among the most intriguing archaeological phenomena in pre-colonial South America, extending from approximately 8,000 to 1,000 years before present (yr BP) across 3,000 km on the Atlantic coast. However, little is known about their connection to early Holocene hunter-gatherers, how this may have contributed to different historical pathways and the processes through which late Holocene ceramists came to rule the coast shortly before European contact. To contribute to our understanding of the population history of indigenous societies on the eastern coast of South America, we produced genome-wide data from 34 ancient individuals as early as 10,000 yr BP from four different regions in Brazil. Early Holocene hunter-gatherers were found to lack shared genetic drift among themselves and with later populations from eastern South America, suggesting that they derived from a common radiation and did not contribute substantially to later coastal groups. Our analyses show genetic heterogeneity among contemporaneous Sambaqui groups from the southeastern and southern Brazilian coast, contrary to the similarity expressed in the archaeological record. The complex history of intercultural contact between inland horticulturists and coastal populations becomes genetically evident during the final horizon of Sambaqui societies, from around 2,200 yr BP, corroborating evidence of cultural change.

First Paleogenetic Evidence of Probable Syphilis and Treponematoses Cases in the Brazilian Colonial Period.

Despite interest in the origins of syphilis, paleopathological analysis has not provided answers, and paleogenetic diagnosis remains a challenge. Even venereal syphilis has low infectivity which means there are few circulating bacteria for most of the individual's life. Human remains recovered from the Nossa Senhora do Carmo Church (17th to 19th centuries) and the Praça XV Cemetery (18th to 19th centuries), Rio de Janeiro, Brazil, were subjected to Treponema paleogenetic analysis. Historical data point to endemic treponemal infections in the city, including venereal syphilis. Based on the physiopathology of Treponema pallidum infection, 25 samples, mostly from skull remains of young adults, with no visible paleopathological evidence of treponematoses, were analyzed. PCR with three molecular targets, tpp47, polA, and tpp15, were applied. Ancient DNA tpp15 sequences were recovered from two young adults from each archaeological site and revealed the polymorphism that characterizes T. p. subsp. pallidum in a female up to 18 years old, suggesting a probable case of syphilis infection. The results indicated that the epidemiological context and the physiopathology of the disease should be considered in syphilis paleogenetic detection. The findings of Treponema sp. aDNA are consistent with historical documents that describe venereal syphilis and yaws as endemic diseases in Rio de Janeiro. Data on the epidemiological characteristics of the disease and its pathophysiology offer new perspectives in paleopathology.

Tuberculosis in post-contact Native Americans of Brazil: Paleopathological and paleogenetic evidence from the Tenetehara-Guajajara.

Tuberculosis (TB) has been described in Native American populations prior to the arrival of European explorers, and in Brazilian populations dating from the Colonial Period. There are no studies demonstrating TB infection in native Brazilians, and the history and epidemiological scenario of TB in Brazil is still unknown. The aim of this study was to verify the presence of TB infection among the native Tenetehara-Guajajara population from Maranhão State, Brazil, 210 ± 40 years ago. A Tenetehara-Guajajara skeleton collection was submitted to paleopathological analysis, and rib bone samples (n = 17) were used for paleogenetic analysis based on Mycobacterium tuberculosis complex (MTC) targets. Porotic hyperostosis and cribra orbitalia were found in 10 and 13 individuals, respectively. Maternal ancestry analysis revealed Native American mtDNA haplogroups A and C1 in three individuals. Three samples showed osteological evidence suggestive of TB. katG and mtp40 sequences were detected in three individuals, indicating probable TB infection by two MTC lineages. Tuberculosis infection in the Tenetehara-Guajajara population since the 18th century points to a panorama of the disease resulting, most probably, from European contact. However, the important contribution of African slaves in the population of Maranhão State, could be also considered as a source of the disease. This study provides new data on TB during the Brazilian Colonial Period. This is the first report integrating paleopathological and paleogenetic data for the study of TB in Brazil.

Estresse, doença e adaptabilidade: estudo comparativo de dois grupos pré-históricos em perspectiva biocultural / Stress, disease and adaptability

O estudo de indicadores inespecíficos de estresse e condiçöes patológicas em restos esqueletais tem sido desenvolvido, em paleopatologia, em abordagem biocultural. Tenta aproximar o conceito de estresse aos de doença e adptabilidade dos grupos humanos. Embora sendo ainda um enfoque pouco desenvolvido no Brasil, seu emprego no presente trabalho teve por objetivo ampliar as possibilidades da reconstruçäo pré-histórica e testar um pressuposto sobre a existência de melhor qualidade de vida entre os grupos do litoral. Foram reunidos dados sobre indicadores de estresse, condiçöes patológicas e demografia de duas coleçöes funerárias pré-históricas. A primeira representando um grupo que sepultou seus mortos na Furna do Estrago, Pernambuco, uma ocupaçäo de interior; a segunda, representando um grupo que sepultou no sambaqui de Cabeçuda, Santa Catarina, uma ocupaçäo tipicamente adaptada ao litoral. A patocenose mostrou, no primeiro caso, estresse locomotor intenso, na forma de fraturas e artrose, acarretando provável prejuízo adaptativo ao nível da performance física; além de estreita consanguinidade entre os indivíduos, numerosas anomalias ou variaçöes morfológicas, e baixa expressividade das doenças infecto-parasitárias. No segundo caso, associaçöes de sinais de descontinuidades fisiológicas e sinais patológicos sugestivos de anemia, apontam para a provável existência de estresse infeccioso endêmico, cuja explicaçäo poderia ser a hiperexposiçäo a bactérias patogênicas de águas salinas. Modelos bioculturais correlacionando os dados sobre doença, estresse, padröes culturais e meio ambiente foram propostos em cada caso. Os fatores de estresse, as respostas biológicas, os mecanismos culturais de compensaçäo, e possíveis tendências adaptativas foram discutidas, na tentativa de formular hipóteses para investigaçäo futura.