Global analysis of saliva as a source of bacterial DNA - a potential chronometer for human population and migration studies

• Antragsteller: Professor Dr. Hans-Peter Horz
• Fachliche Zuordnung: Parasitologie und Biologie der Erreger tropischer Infektionskrankheiten
• Förderung: Förderung von 2010 bis 2016
• Projektkennung: Deutsche Forschungsgemeinschaft (DFG) - Projektnummer 168536437

The history of Homo sapiens – a highly challenging field of study – has traditionally been explored by assessing classical human DNA markers. Alternatively, because of their higher evolution rate human-associated bacteria principally hold great potential for providing complementary information on human history and could particularly be useful for shedding light on migrations that are too recent to be studied with human DNA markers. The concept of human-bacterial co-evolution has already been successfully tested for Helicobacter pylori however its analysis requires stomach-biopsies. The aim of this project is to test the hypothesis that members of the human salivary microbiota may function as chronometer of human evolution and thus allow a fine-scale differentiation of human populations. Saliva samples from 10 volunteers each from 12 world-wide areas, representing diverse ethnic groups, will be analyzed. The bacteria of choice will be Streptococcus oralis and Fusobacterium nucleatum, because they are primarily transmitted vertically, easily detectable in human saliva, and distinguishable down to subspecies and clonal-cluster level using defined and well-established marker genes. In addition, terminal restriction fragment length polymorphism (T-RFLP) analysis will be performed to compare the microbial community compositions across samples. This project which is a unique collaboration between a microbiology group and an anthropology group will establish a framework for the identification of bacterial DNA markers from saliva with the ultimate potential to provide new perspectives on unsolved human migration patterns – an issue of great social, anthropological, and medical importance.

• DFG-Verfahren: Sachbeihilfen