Wydawnictwo i Pracownia Archeologiczna PROFIL-ARCHEO eBooks, Dec 31, 2021
The anthropological analysis was conducted for human remains found at the bi-ritual cemetery of t... more The anthropological analysis was conducted for human remains found at the bi-ritual cemetery of the Upper Silesian-Lesser Poland group of the Lusatian culture in Gogolin-Strzebniów. Osteological materials were discovered in 29 cremation graves and 3 inhumation burials, and remains of 38 individuals were identified. Whenever it was possible, the age and sex of the buried were estimated. The degree of bone burning and the weight of cremated bones from one grave were also determined. Most of the graves were single burials, four contained remains of two individuals and in one grave three individuals were buried. Burials of adults of Maturus age (35–50 years) dominated at the cemetery and these were mostly male individuals. The lower share of female graves may result from the fragmentary examination of the cemetery, but may also ofreflect sex-related differences in the burial rite. At the analysed cemetery a similar number of children aged Infans I (0–6 years) and Infans II (7–14 years) was identified. Usually, at prehistoric necropolises, the burials of younger children dominate. The equal share of these two age categories is sometimes noted at epidemic cemeteries, but in Gogolin it more likely stems from the prevalence of inhumation graves at the cemetery, in which human remains have not survived. Children, both Infans I and Infans II, were buried in single graves or in double burials with adults. All human remains were heavily, evenly burned, the bones were cream-beige in colour, which indicates that the bone temperature was above 800°C, i.e. the temperature in the pyre was 1000–1200°C. The average weight of the burnt bones was 414 g, with significant variations from grave to grave differentiated. The mass of bones from the graves containing the remains of males exceeded the values obtained for female burials. There are also differences in mean and maximum values between younger and older children age classes, which could be explained by the size of the skeleton. The obtained data demonstrate that at the analysed cemetery, as at other contemporary sepulchral sites, only part of human remains were placed in the graves, which probably was an effect of the applied funeral rite. Anthropological investigations allowed for the observation of the distribution of burials at the cemetery. The obtained planigraphic information indicates that there are no provinces grouping individuals of similar age or the same sex.
Due to postmortem DNA degradation andmicrobial colonization,most ancient genomes have low depth o... more Due to postmortem DNA degradation andmicrobial colonization,most ancient genomes have low depth of coverage, hindering genotype calling. Genotype imputation can improve genotyping accuracy for low-coverage genomes. However, it is unknown how accurate ancient DNA imputation is and whether imputation introduces bias to downstream analyses. Here we re-sequence an ancient trio (mother, father, son) and downsample and impute a total of 43 ancient genomes, including 42 high-coverage (above 10x) genomes.We assess imputation accuracy across ancestries, time, depth of coverage, and sequencing technology.We find that ancient and modern DNA imputation accuracies are comparable. When own sampled at 1x, 36 of the 42 genomes are imputed with low error rates (below 5%) while African genomes have higher error rates. We validate imputation and phasing results using the ancient trio data and an orthogonal approach based on Mendel’s rules of inheritance. We further compare the downstreamanalysis results between imputed and high-coverage genomes, notably principal component analysis, genetic clustering, and runs of homozygosity, observing similar results starting from0.5x coverage, except for the African genomes. These results suggest that, for most populations and depths of coverage as low as 0.5x, imputation is a reliable method that can improve ancient DNA studies.
Wydawnictwo i Pracownia Archeologiczna PROFIL-ARCHEO eBooks, Dec 31, 2021
The anthropological analysis was conducted for human remains found at the bi-ritual cemetery of t... more The anthropological analysis was conducted for human remains found at the bi-ritual cemetery of the Upper Silesian-Lesser Poland group of the Lusatian culture in Gogolin-Strzebniów. Osteological materials were discovered in 29 cremation graves and 3 inhumation burials, and remains of 38 individuals were identified. Whenever it was possible, the age and sex of the buried were estimated. The degree of bone burning and the weight of cremated bones from one grave were also determined. Most of the graves were single burials, four contained remains of two individuals and in one grave three individuals were buried. Burials of adults of Maturus age (35–50 years) dominated at the cemetery and these were mostly male individuals. The lower share of female graves may result from the fragmentary examination of the cemetery, but may also ofreflect sex-related differences in the burial rite. At the analysed cemetery a similar number of children aged Infans I (0–6 years) and Infans II (7–14 years) was identified. Usually, at prehistoric necropolises, the burials of younger children dominate. The equal share of these two age categories is sometimes noted at epidemic cemeteries, but in Gogolin it more likely stems from the prevalence of inhumation graves at the cemetery, in which human remains have not survived. Children, both Infans I and Infans II, were buried in single graves or in double burials with adults. All human remains were heavily, evenly burned, the bones were cream-beige in colour, which indicates that the bone temperature was above 800°C, i.e. the temperature in the pyre was 1000–1200°C. The average weight of the burnt bones was 414 g, with significant variations from grave to grave differentiated. The mass of bones from the graves containing the remains of males exceeded the values obtained for female burials. There are also differences in mean and maximum values between younger and older children age classes, which could be explained by the size of the skeleton. The obtained data demonstrate that at the analysed cemetery, as at other contemporary sepulchral sites, only part of human remains were placed in the graves, which probably was an effect of the applied funeral rite. Anthropological investigations allowed for the observation of the distribution of burials at the cemetery. The obtained planigraphic information indicates that there are no provinces grouping individuals of similar age or the same sex.
Due to postmortem DNA degradation andmicrobial colonization,most ancient genomes have low depth o... more Due to postmortem DNA degradation andmicrobial colonization,most ancient genomes have low depth of coverage, hindering genotype calling. Genotype imputation can improve genotyping accuracy for low-coverage genomes. However, it is unknown how accurate ancient DNA imputation is and whether imputation introduces bias to downstream analyses. Here we re-sequence an ancient trio (mother, father, son) and downsample and impute a total of 43 ancient genomes, including 42 high-coverage (above 10x) genomes.We assess imputation accuracy across ancestries, time, depth of coverage, and sequencing technology.We find that ancient and modern DNA imputation accuracies are comparable. When own sampled at 1x, 36 of the 42 genomes are imputed with low error rates (below 5%) while African genomes have higher error rates. We validate imputation and phasing results using the ancient trio data and an orthogonal approach based on Mendel’s rules of inheritance. We further compare the downstreamanalysis results between imputed and high-coverage genomes, notably principal component analysis, genetic clustering, and runs of homozygosity, observing similar results starting from0.5x coverage, except for the African genomes. These results suggest that, for most populations and depths of coverage as low as 0.5x, imputation is a reliable method that can improve ancient DNA studies.
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Papers by Anita Szczepanek
orthogonal approach based on Mendel’s rules of inheritance. We further
compare the downstreamanalysis results between imputed and high-coverage genomes, notably principal component analysis, genetic clustering, and runs of homozygosity, observing similar results starting from0.5x coverage, except for the African genomes. These results suggest that, for most populations and depths of coverage as low as 0.5x, imputation is a reliable method that can improve ancient DNA studies.
orthogonal approach based on Mendel’s rules of inheritance. We further
compare the downstreamanalysis results between imputed and high-coverage genomes, notably principal component analysis, genetic clustering, and runs of homozygosity, observing similar results starting from0.5x coverage, except for the African genomes. These results suggest that, for most populations and depths of coverage as low as 0.5x, imputation is a reliable method that can improve ancient DNA studies.