Assessment of STR Typing Success Rate in Soft Tissues from Putrefied Bodies Based on a Quantitative Grading System for Putrefaction

J Forensic Sci. 2015 Jul;60(4):1016-21. doi: 10.1111/1556-4029.12746. Epub 2015 Mar 24.

Abstract

To date, there is no systematic investigation of the association of short tandem repeat (STR) typing success rate in soft tissues with different signs of putrefaction. Herein, putrefaction was rated using a newly developed 19-parameter system in soft tissues from a collective of 68 decaying bodies, and DNA yield was determined in 408 samples. DNA integrity was rated using a self-devised pentaplex PCR generating an "integrity score" (Si). STR typing success rate was then assessed for selected cases. DNA yield and Si differed significantly between tissues with kidney on average exhibiting the highest Si values. Statistical analysis revealed that nine parameters were significantly and positively correlated with Si . The observed values for each of these nine parameters were summed up to generate a putrefaction score (Sp) for each sample. Our results show that STR typing success rate can be predicted based on Sp before expensive multiplex STR profiling is performed.

Keywords: DNA integrity; DNA profiling; disaster victim identification; forensic genetics; forensic science; putrefaction.

MeSH terms

  • Aorta / chemistry
  • Brain Chemistry
  • DNA / analysis*
  • DNA Fingerprinting*
  • Female
  • Humans
  • Kidney / chemistry
  • Liver / chemistry
  • Lung / chemistry
  • Male
  • Microsatellite Repeats*
  • Polymerase Chain Reaction
  • Postmortem Changes*
  • Psoas Muscles / chemistry

Substances

  • DNA