skip navigation

CrimeSolutions.gov

Add your conference to our Justice Events calendar

PUBLICATIONS

NCJRS Abstract

The document referenced below is part of the NCJRS Library collection.
To conduct further searches of the collection, visit the NCJRS Abstracts Database.

How to Obtain Documents
 
NCJ Number: NCJ 241108     Find in a Library
Title: Demonstration of DSI-Semen - A Novel DNA Methylation-Based Forensic Semen Identification Assay
Journal: Forensic Science International: Genetics  Volume:7  Issue:1  Dated:January 2013  Pages:136 to 142
Author(s): Adam Wasserstrom ; Dan Frumkin ; Ariane Davidson ; Moshe Shpitzen ; Yael Herman ; Ron Gafny
Date Published: 01/2013
Page Count: 7
Publisher: http://www.elsevier.com 
Type: Report (Study/Research)
Language: English
Country: United States of America
Annotation: Determining whether the source tissue of biological material is semen is important in confirming sexual assaults, which account for a considerable percentage of crime cases. The gold standard for confirming the presence of semen is microscopic identification of sperm cells, however, this method is labor intensive and operator-dependent. Protein-based immunologic assays, such as PSA, are highly sensitive and relatively fast, but suffer from low specificity in some situations. In addition, proteins are less stable than DNA under most environmental insults. Recently, forensic tissue identification advanced with the development of several approaches based on mRNA and miRNA for identification of various body fluids. Herein is described DNA source identifier (DSI)-semen, a DNA-based assay that determines whether the source tissue of a sample is semen based on detection of semen-specific methylation patterns in five genomic loci.
Abstract: The assay is comprised of a simple single tube biochemical procedure, similar to DNA profiling, followed by automatic software analysis, yielding the identification (semen/non-semen) accompanied by a statistical confidence level. Three additional internal control loci are used to ascertain the reliability of the results. The assay, which aims to replace microscopic examination, can easily be integrated by forensic laboratories and is automatable. The kit was tested on 135 samples of semen, saliva, venous blood, menstrual blood, urine, and vaginal swabs and the identification of semen vs. non-semen was correct in all cases. In order to test the assay's applicability in "real-life" situations, 33 actual casework samples from the forensic biological lab of the Israeli police were analyzed, and the results were compared with microscopic examination performed by Israeli police personnel. There was complete concordance between both analyses except for one sample, in which the assay identified semen whereas no sperm was seen in the microscope. This sample likely represents true semen because sperm cells were detected from an adjacent sample from the same garment, therefore in this case the assay appears to be more sensitive than the microscopic examination. These results demonstrate that this assay is a bona fide confirmatory test for semen. (Published Abstract)
Main Term(s): Forensics/Forensic Sciences
Index Term(s): Evidence identification and analysis ; Blood/body fluid analysis ; Sexual assault ; Rape investigations ; Investigative techniques ; DNA fingerprinting ; Foreign criminal justice research ; Israel
   
  To cite this abstract, use the following link:
https://www.ncjrs.gov/App/Publications/abstract.aspx?ID=263196

* A link to the full-text document is provided whenever possible. For documents not available online, a link to the publisher's web site is provided.