Estimating postmortem interval using RNA degradation and morphological changes in tooth pulp

Details

• Personal Author:
  Bishop CP ; Hobbs GR ; Wells JD ; Young ST
• Description:
  The accurate determination of time since death, or postmortem interval (PMI), can be critical in the investigation of suspicious deaths. Knowing when a suspicious death occurred can limit the number of potential suspects to those without a viable alibi for the time of the crime. The forensic techniques currently employed to determine PMI: pathology, entomology, and anthropology, are accurate over different time periods following death. A large gap in time exists between the capabilities of forensic entomology and traditional anthropology, leaving a period in which PMI is difficult to estimate. In this study, time-dependent differences in RNA decay rates were examined to extend the time frame over which early PMI estimates can be made. Comparing the decay rates of a large, labile segment of B-actin RNA and a smaller, more stable, non-overlapping segment of the same RNA from tooth pulp, we were able to estimate PMI values of pigs buried within a shallow grave for up to 84 days. This compares favorably to an estimate of PMI using insect data. Full skeletonization and loss of insect activity was observed by day 28 of our study. In addition to differences in RNA decay rates, morphological changes were observed in the pulp as it aged postmortem. To provide a quantitative measure of progressive color changes, analysis of digital photographs of each tooth's pulp were used to construct a simple colorimetric assay. This assay was then used to cluster ages of pulp samples by color. The two assays, used in combination with one another, can create a more precise estimate of PMI. The potential advantages of this molecular means of estimating PMI include extending the time frame for such estimates, is applicable to samples collected worldwide (no specialized knowledge of local insect fauna is required), is relatively fast, and inexpensive. [Description provided by NIOSH]
• Subjects:
  Animals Autopsy Colorimetry Genetics Insecta Mortality Occupational Health Pathology Safety
• Keywords:
  Author Keywords: Postmortem Interval Fatalities Forensic Medicine Insects Morphology Polymerase Chain Reaction Postmortem Examination Quantitative Reverse Transcription Real-time Ribonucleic Acids Skeletal System
• ISSN:
  0379-0738
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  Florida ; OSHA Region 3 ; OSHA Region 4 ; West Virginia
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  229
• Issue:
  1
• NIOSHTIC Number:
  nn:20049492
• Citation:
  Forenic Sci Int 2013 Jun; 229(1-3):163.e1-163.e6
• Contact Point Address:
  Clifton P. Bishop, Department of Biology, West Virginia University, 53 Campus Drive, Morgantown, WV 26506
• Email:
  cbishop@mail.wvu.edu
• Federal Fiscal Year:
  2013
• Performing Organization:
  West Virginia University
• Peer Reviewed:
  False
• Start Date:
  20050701
• Source Full Name:
  Forensic Science International
• End Date:
  20250630
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:38eca434fa66b5a62f7019cae987f491770f2ddbfeeb459ddb8b6207753dda079d8f1acfbe620913edfaebb2d87b4215dcf994ffa48ff9d513e627674685cbb1
• Download URL:
  https://stacks.cdc.gov/view/cdc/203933/cdc_203933_DS1.pdf
• File Type:
  [PDF - 480.37 KB ]