- Forensic Seminar - "A molecular genetic approach to estimating an extended postmortem interval"
Forensic Seminar - "A molecular genetic approach to estimating an extended postmortem interval"
"A molecular genetic approach to estimating an extended postmortem interval.”
Dr. Clifton Bishop, Dept. Biology, West Virginia University.
Estimating the time since death, or postmortem interval (PMI), can greatly aid an investigation of a suspicious death. Knowing PMI can limit the number of suspects or contradict witness testimony. Because of the typical pattern of postmortem decay, the value of analytical methods tends to shift from pathology to entomology to anthropology with increasing PMI. However, under many circumstances there is a gap in time between when entomology and anthropology are useful for this purpose.
We have developed a postmortem clock based on the relative decay rates of separate large and small sections of the same β-actin RNA molecule. Initial experiments suggest that this approach can be used to estimate the time of deposition of a bloodstain at least up 30 days later, and when applied to tooth pulp can be used to estimate PMI of a buried corpse for up to 84 days, when insects were no longer present after day 28.