The goal of extraction is to release DNA from the mineral matrix (bone) while removing inhibitors like humic acids.
Software checks for high rates of C-to-T transitions at the ends of DNA fragments. If these "nicks" are present, it’s a signature of authenticity.
All work must be done in a dedicated "Clean Lab" with HEPA filtration, positive air pressure, and UV sterilization. Researchers wear full-body suits to prevent shedding their own DNA onto the samples. Ancient DNA: Methods and Protocols
Synthetic DNA "adapters" are attached to the ends of the fragments, allowing them to bind to the sequencing platform.
Samples are ground into a fine powder and soaked in EDTA, which chelates calcium and dissolves the bone matrix. The goal of extraction is to release DNA
If the sample has low endogenous DNA (e.g., 99% of the DNA is from soil bacteria), researchers use "baits"—RNA probes that match the target genome—to "fish out" the human or animal DNA of interest. 5. Bioinformatic Authentication The final step is proving the DNA is actually ancient.
The exterior of the bone or tooth is usually mechanically removed (sanding) or treated with bleach and UV light to remove surface contaminants. 3. Extraction Methods All work must be done in a dedicated
Working with aDNA is fundamentally different from modern genomics due to three primary hurdles: