To handle chemical damage, researchers may use Uracil-DNA-Glycosylase (UDG) to remove uracil bases, reducing sequencing errors, though this can sometimes shorten already tiny fragments.
Modern DNA from researchers or the environment is "fresher" and more intact than aDNA, making it easy for a tiny amount of modern DNA to overwhelm the ancient sample. 2. Sample Selection and Preparation Ancient DNA: Methods and Protocols
The goal of extraction is to release DNA from the mineral matrix (bone) while removing inhibitors like humic acids. Sample Selection and Preparation The goal of extraction
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. Software checks for high rates of C-to-T transitions
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.
Samples are ground into a fine powder and soaked in EDTA, which chelates calcium and dissolves the bone matrix.