DNA extraction and analysis of skeletal remains
(English)Manuscript (preprint) (Other academic)
Skeletal remains are often exposed to diverse conditions that affect the biological material in different ways. As a consequence, DNA in aged skeletal remains is often present in minute amounts, highly degraded and contains inhibitors that can affect the amplification reaction. These issues together with the high risk of contamination with exogenous DNA make molecular analysis of old remains a challenging task. Efficient methods for the extraction of DNA that maximise the yield and simultaneously remove inhibitors as well as contaminants would therefore be desirable, both for forensic investigations and for the study of ancient DNA analysis.
This study describes the evaluation of three protocols for extraction of DNA from aged skeletal remains. Whole and pulverised samples from a skull and ulna that had been buried for approximately 70 years were treated with bleach and different concentrations of EDTA and proteinase K. The DNA was thereafter extracted using a salting out procedure based on the Wizard® Genomic Purification system. The efficiency of the three protocols was estimated by mtDNA quantification, which revealed that the extracts contained between 0 and 14 110 copies/100mg bone. In general, the ulna bone resulted in higher yields of mtDNA compared to the skull bone. The most efficient extraction protocol was the one involving the highest concentration of EDTA. Soaking the bone samples in commercial bleach prior to extraction was found to be a useful method of eliminating contaminants while retaining sufficient DNA for analysis. Moreover, a maternal relationship was investigated for the remains analysed in this study.
mtDNA, DNA extraction, skeletal remains, decontamination
IdentifiersURN: urn:nbn:se:uu:diva-132069OAI: oai:DiVA.org:uu-132069DiVA: diva2:356813