Isolation and analysis of DNA from archaeological, clinical, and natural history specimens.

The use of ancient DNA (aDNA) in the reconstruction of population origins and evolution is becoming increasingly common. Novel methods exist for the isolation, purification, and analysis of aDNA because these DNA templates are likely to be damaged, fragmented and?or associated with non-nucleic acid material. However, contamination of ancient specimens and DNA extracts with modern DNA is more widespread than is generally acknowledged and remains a significant problem in aDNA analysis. Studies of human aDNA are uniquely sensitive to contamination due to the continual presence of potential contamination sources. Meticulous authentication of results and careful selection of polymorphic markers capable of distinguishing between aDNA and probable DNA contaminants are critical to a successful aDNA study.