Pretreatment: Improving Endogenous Ancient DNA Yields Using a Simple Enzymatic Predigestion Step

Area of Science:

• Paleogenomics
• Molecular Biology
• Ancient DNA Analysis

Background:

• Ancient DNA (aDNA) samples are mixtures of endogenous and exogenous DNA.
• Contamination, primarily microbial and modern human DNA, reduces the proportion of authentic aDNA.
• Existing protocols often use harsh chemical treatments like bleach to reduce contamination.

Purpose of the Study:

• To present a novel, less aggressive pretreatment protocol for aDNA extraction.
• To enhance the endogenous DNA fraction by reducing exogenous contaminants.
• To offer an alternative to aggressive chemical washes for aDNA sample preparation.

Main Methods:

• Development of a brief predigestion step using an EDTA-based lysis buffer.
• Application of the EDTA buffer pretreatment prior to DNA extraction.
• Comparison of the EDTA method with existing pretreatment protocols (implied).

Main Results:

• The EDTA-based predigestion effectively increases the endogenous DNA fraction.
• This method provides a less aggressive approach compared to chemical washes.
• Improved yield of authentic aDNA is achieved prior to downstream analyses.

Conclusions:

• The EDTA-based lysis buffer predigestion is a viable and gentler method for enriching endogenous DNA in ancient samples.
• This protocol offers a promising alternative for ancient DNA researchers seeking to maximize authentic DNA recovery.
• The method contributes to advancing ancient DNA extraction techniques for more reliable results.