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Aging Blow Fly Egg Using Gene Expression: A Feasibility Study

NCJ Number
Journal of Forensic Sciences Volume: 52 Issue: 6 Dated: November 2007 Pages: 1350-1354
Date Published
November 2007
5 pages

In order to facilitate more precise estimates of the age of blow flies on a host corpse for the purpose of increasing the accuracy of estimating the host's time of death, this study profiled the expression of three blow-fly genes (bcd, sll, and cs) throughout the maturation of blow-fly eggs.


The findings show that the blow-fly egg stage, which lasts only several hours, can be divided into smaller periods by using gene-expression data. Other stages of fly development that last longer, and are therefore more forensically challenging, can also be examined with this method. In addition, the use of more developmentally regulated genes in the analysis should further increase the precision of age estimates by providing more age-informative data. A detailed description of materials and methods of the study addresses species identification and egg collection, gene sequencing and primer design, and cDNA synthesis and quantitative PCR. 1 table, 4 figures, and 20 references

Date Published: November 1, 2007