Amplification of DNA remnants in mummified human brains from medieval Joseon tombs of Korea

Recently, a number of mummified brains obtained from the remains of medieval Joseon Koreans have been subjected to biological investigations. Although the morphology of the organs had been perfectly maintained on gross examination, we still do not know how well biomolecules such as DNA were preserved. In the present study, the preservation status of remnant DNA in mummified brain tissue was determined by means of comparisons with corresponding DNA taken from the femurs of the same subjects. Quantifiler analysis revealed that DNA from the mummified brain was less fragmented than that contained in the femurs. The better preservation status of the brain DNA was shown also in MiniFiler assays: the number of short tandem repeat (STR) locus profiles for the mummified brain was far higher than in the case of the femur bones. In the case of the mtDNA analysis, longer DNA fragments (821 bp) could be successfully amplified with brain samples, whereas only shorter PCR amplicons (221-263 bp) were seen with the femur samples. Indeed mummified brain tissue, if discovered in amounts suitable for ancient DNA analysis, promises to be the preferred source for genetic analysis of individuals from pre-modern Korean tombs.