NCJ Number
131267
Journal
Journal of Forensic Sciences Volume: 36 Issue: 4 Dated: (July 1991) Pages: 1198-1203
Date Published
1991
Length
6 pages
Annotation
The application of a quantification method for human DNA to forensic science is illustrated in two casework examples.
Abstract
In both cases, DNA samples were extracted from skin tissue and blood stained clothing recovered from different crime scenes. DNA quantification by ethidium bromide/agarose gel electrophoresis and ultraviolet light fluorescence yielded approximately 0.5 micrograms/microliter of high molecular weight DNA. Quantification of human genomic DNA with the human specific DNA probe p17H8 (Locus D17Z1) revealed that more than 99 percent of the DNA extracted from the skin sample was of nonhuman origin and that the bloodstained clothing was devoid of human DNA sequences. These cases demonstrate the importance of quantifying the amount of human genomic DNA in forensic casework DNA samples. Because samples may be heavily contaminated with nonhuman DNA and at the same time be indistinguishable from pure human genomic DNA according to ethidium bromide/gel electrophoresis, slot-blot hybridization in conjunction with electrophoresis is recommended for DNA analysis. The degree of contaminations needs to be determined prior to DNA typing. 2 figures and 10 references (Author abstract modified)