NCJ Number
225301
Journal
Canadian Society of Forensic Science Journal Volume: 41 Issue: 2 Dated: June 2008 Pages: 53-60
Date Published
June 2008
Length
8 pages
Annotation
This study examined the recovery and typing of human DNA from biological samples placed on various substrates in a house fire.
Abstract
Recovered samples deposited on substrates that were more combustible by nature, or were more exposed to direct flame, yielded less DNA typing information; the results show that overall for 59 percent of the samples recovered (58 samples out of 98), a complete and accurate DNA profile was obtained. When the results were separated by room, a different pattern emerged. Of the 98 sample collected, 40 were from the rooms in which the fire was started. Of these 40 samples, only 25 percent (10 of the 40) gave a full profile compared to over 80 percent (48 out of 58) from the other rooms. This suggests that high heat and flame affect the ability to recover human DNA and obtain a full DNA typing profile, whereas the use of regular combustibles to start the fire, and regular water or wet water to extinguish the fire does not. Of secondary interest was whether the use of wet water would interfere with the ability to obtain a DNA typing profile from a sample. The use of wet water only involved four samples and that does not represent a complete investigation, however, all four samples were completely soaked with the wet water and still yielded complete DNA typing profiles. Stains that resembled blood were distinguishable from recovered blood stains; scrapings of samples showed higher DNA yields than swabs. Data were collected from a duplicated arson crime scene. Tables and references