DNA preservation: a microsatellite-DNA study on ancient skeletal remains

Area of Science:

• Archaeogenetics
• Environmental Archaeology
• Molecular Anthropology

Background:

• DNA degradation is a major challenge in ancient sample analysis.
• Environmental conditions at archaeological sites profoundly influence biomolecular preservation.
• Understanding DNA preservation factors is key to successful ancient DNA extraction and analysis.

Purpose of the Study:

• To investigate the influence of various environmental factors on DNA preservation in archaeological human teeth.
• To identify key environmental parameters affecting the quantity and quality of ancient DNA.
• To correlate environmental conditions with DNA integrity for improved ancient DNA recovery.

Main Methods:

• Analysis of DNA content in archaeological teeth from diverse environmental settings.
• Measurement of environmental factors: temperature, humidity, soil pH, geochemistry, organic content, and microbial load.
• Quantification of relative DNA content using polymerase chain reaction (PCR) amplification success rates.

Main Results:

• Dryness, low temperatures, and absence of microorganisms significantly favor DNA preservation.
• Neutral to slightly alkaline soil pH supports the preservation of both DNA and bioapatite.
• Storage conditions impact DNA amplifiability; prolonged room temperature storage reduces DNA quantity and reproducibility.

Conclusions:

• Environmental factors like temperature, humidity, and microbial activity are critical determinants of ancient DNA preservation.
• Optimal conditions for DNA preservation in archaeological contexts include cool, dry, and low-microbial environments.
• Proper sample storage, particularly avoiding prolonged room temperature exposure, is essential for maintaining DNA integrity in ancient specimens.