DNA analysis of neonatal human remains wrapped and kept in a vinyl bag for 15 years.

DNA analysis of a newborn baby wrapped and kept in a vinyl bag for 15 years was performed. DNA isolated from the femur and humerus was used to determine the sex and kinship between the infant and the putative parents. Amplification of mtDNA, ABO, HLA, CST3, CST5, VWA, D12S66, D21S11, CSF1PO, TPOX, THO1 and 10Y polymorphisms and the amelogenin gene was carried out. Several mtDNA types were obtained, suggesting that the sample was contaminated by exogenous DNAs. One of the DNA samples obtained from the femur showed an identical mtDNA sequence to that of the mother except for one site, and this pattern was also found in another DNA sample. None of our laboratory personnel had that type, so we thought it was possible that this sample contained the target DNA. However, maternity was denied by the CST3 polymorphism. Finally, we concluded that the sample had been contaminated with exogenous DNA before we started to examine the body. Although it is difficult to determine the sources of this contamination, PCR amplification from highly degraded DNA is very sensitive to such contamination, and we must be even more careful in DNA analysis of such samples than in that of not so severely degraded specimens.