Susanne Hummel’s research while affiliated with University of Göttingen and other places

The analysis of ancient DNA (aDNA) from human skeletal remains can provide useful insights when investigating archaeological finds. One popular application of aDNA is to examine genealogical relationships between individuals recovered at the same archaeological site. For the reconstruction of genealogical relationships, several genetic markers are commonly used: autosomal STRs, mitochondrial lineages (based on SNP-analysis) and Y-chromosomal haplotypes (based on Y-STR-analysis). In this paper, we present the additional opportunities that X-STRs provide in aDNA kinship reconstruction, especially in deficiency cases and for the examination of father-daughter relationships. Possible applications are demonstrated on a range of different kinship reconstructions: confirmation of half-siblingship in the Lichtenstein cave (Germany), exclusion of two potential father-daughter relationships in Goslar (Germany), investigation of three siblingships in Boilstädt (Germany) as well as the confirmation of a father-daughter relationship in Stolpe (Germany). This study shows that the analysis of X-STRs can contribute to the investigation of relationship constellations otherwise difficult to approach (e.g. father-daughter relationships) and that X-STRs are useful to support and complement autosomal STRs, mtDNA and Y-STR data.

My project aims to show that forensic DNA phenotyping using the Dynamic Array™ IFC by Fluidigm® is a useful tool in answering various anthropological research questions. The method will be applied to DNA of different conservation and degradation stages with samples from the Meso- and Neolithic over the Middle Ages to modern history to conclude the general suitability of forensic DNA phenotyping for anthropological questions. Exemplarily four research subjects are addressed: Development of the European Phenotype, Identification, Museal Portrayal and Provenance Research.

For microscopic investigation, archaeological bone samples are often embedded in Biodur ® epoxy resin. This study wants to test whether it is possible to extract DNA suitable for PCR amplification from this sample type. For eight individuals a set of samples – each consisting of a Biodur-embedded femur sample, a native femur sample and a control sample of different anatomical origin – were submitted to organic DNA extraction. The extraction success was tested by autosomal short tandem repeat amplification. Seven out of eight Biodur-embedded femur samples revealed successful amplification results. If Biodur-embedded bone material exists from earlier microscopic investigations, our results encourage the use of this sample type as a source for genetic research.

Objectives: The focus of this research is to evaluate the sex estimation methods on isolated human materials by applying morphological methods published in various forensic and anthropological literature on different skeletal series. Materials and Methods: 165 individuals from the 19th to 20th century Inden skeletal series, 252 individuals from the 13th to 14th century Lübeck skeletal series of German ancestry housed at the Department of Historical Anthropology and Human Ecology, the University of Göttingen, Germany, and 161 individuals from the 19th and 20th century of South African African ancestry housed within the Raymond A. Dart collection of modern human skeletons at the University of Witwatersrand, South Africa, with crania, mandibles, and pelves, were assessed. The evaluation criteria are burial information on the Inden series, genetic sex on both the Inden and the Lübeck series, and previous demography on cadavers from the South African African series. Results and Discussion: The sex estimation with cranial traits perform better in Inden and South Africa samples and worse in Lübeck sample. The mandible accuracies for pooled sexes are not exemplary, but the individual traits perform better for males in the Inden, Lübeck, and South Africa samples, except for gonion and angle, which performs better in females. The pelvic traits perform better in the Inden and South Africa samples compared to the Lübeck sample. The statistical tests show that there is a huge difference in the accuracy rates and the performance between both population groups from Germany itself, considering that Inden and Lübeck samples share the same ancestry. The accuracy rates improve with the exclusion of ambiguous individuals.

Agarose gel electrophoresis is a relatively easy to use method, commonly applied to evaluate PCR reaction success. Intercalating agents or dyes are used to visualize the amplified fragments. However, it is uncertain to what extent the brightness of bands is informative about the concentration of the amplicons. To more closely examine the suitability of agarose gel electrophoresis to assess PCR product yield, we quantified the brightness of bands on a gel and compared these data with the results from spectrophotometry, fluorometry and qPCR. Evaluation of the results suggests that assessment of the relative quantity of amplicons by band brightness is precise enough even for post-PCR analysis steps requiring PCR product concentrations within a certain range to function properly.

DNA extraction is of utmost importance in archaeobiology, as it determines the success of further DNA analyses. This study concentrates on the success of ancient DNA extraction using silica spin columns and PCR-based analysis from archaeological skeletal material and investigates the influence of sample quantity, lysis time and lysis temperature during sample preparation. The results show that lysis times ranging from 2 to 48 h are suitable, and that lysis should be carried out at a constant temperature of 56 Celsius. Concerning sample quantity, 10 mg for mitochondrial DNA and 50 mg for chromosomal DNA are sufficient for high quality analyses. Thus invaluable sample material can be saved, and time of sample preparation can be reduced considerably.

Medieval Europe was repeatedly affected by outbreaks of infectious diseases, some of which reached epidemic proportions. A Late Medieval mass burial next to the Heiligen-Geist-Hospital in Lübeck (present-day Germany) contained the skeletal remains of more than 800 individuals who had presumably died from infectious disease. From 92 individuals, we screened the ancient DNA extracts for the presence of pathogens to determine the cause of death. Metagenomic analysis revealed evidence of Salmonella enterica subsp. enterica serovar Paratyphi C, suggesting an outbreak of enteric paratyphoid fever. Three reconstructed S. Paratyphi C genomes showed close similarity to a strain from Norway (1200 CE). Radiocarbon dates placed the disease outbreak in Lübeck between 1270 and 1400 cal CE, with historical records indicating 1367 CE as the most probable year. The deceased were of northern and eastern European descent, confirming Lübeck as an important trading centre of the Hanseatic League in the Baltic region.