DNA fingerprinting from tissues after variable postmortem periods.

DNA typing is a useful tool in forensic cases for determining the identity of remains of humans who have been dead for various periods of time. DNA fingerprinting can be achieved only if high molecular weight DNA (HMWDNA) is extracted from the tissue samples of the bodies even after a long postmortem delay. Analyses were performed on various tissues collected during forensic autopsies of 24 bodies known postmortem ages. Tissues such as blood and kidney were found to be unsuitable for DNA fingerprinting because of a rapid degradation of the DNA after a period of one week. HMWDNA could be successfully extracted from brain cortex regardless of postmortem age.