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Gene Expression During Blow Fly Development: Improving the Precision of Age Estimates in Forensic Entomology

NCJ Number
Journal of Forensic Sciences Volume: 56 Issue: S1 Dated: January 2011 Pages: S112-S122
Date Published
January 2011
11 pages

Presented here is a means of incorporating developmentally regulated gene expression levels into traditional stage and size data, with a goal of more precisely estimating developmental age of immature Lucilia sericata.


Forensic entomologists use size and developmental stage to estimate blow fly age, and from those, a postmortem interval. Since such estimates are generally accurate but often lack precision, particularly in the older developmental stages, alternative aging methods would be advantageous. Generalized additive models of development showed improved statistical support compared to models that did not include gene expression data, resulting in an increase in estimate precision, especially for postfeeding third instars and pupae. The models were then used to make blind estimates of development for 86 immature L. sericata raised on rat carcasses. Overall, inclusion of gene expression data resulted in increased precision in aging blow flies. (Published Abstract)

Date Published: January 1, 2011