Preservation and Recovery of DNA in Postmortem Specimens and Trace Samples

Abstract

Using DNA analysis, trace biological samples can now be used to determine individual identity, with a vanishingly small probability that the sample derived from any other individual. Further, we can now determine genetic sequences from organisms that died more than 100 million years ago. Such remarkable abilities are based on the preservation of DNA in nonliving samples, and we are only beginning to explore the extent to which genetic information can be retrieved after death. Advancements in this area have occurred rapidly in the last 5 to 10 years, and are based on recent developments in molecular biological technology, coupled with a greatly increased understanding of the genetic structure of individuals and populations the fruit of basic research. Moreover, additional developments in both the power and ease of techniques to recover postmortem genetic information can be expected at an increasing pace for the foreseeable future. With the potential to provide exact information concerning species, sex, individual identity and familial kinship, such developments are having a revolutionary impact on forensic science. Other fields which will benefit greatly from access to genetic information from the past include archaeology, population genetics, evolutionary biology, taxonomy and epidemiology.