The DNA Casework Department performs scientific analyses on biological evidence such as blood, semen, and saliva. Technicians and analysts evaluate available information to understand the nature of the case and what questions need to be addressed. They then examine submitted evidence items to locate and identify probative biological samples.
The DNA Casework Department is comprised of two sections (Serology and DNA Analysis) that perform the following functions related to the analysis of biological evidence:
DNA analysis is performed on evidentiary samples and known DNA standards using Short Tandem Repeat Polymerase Chain Reaction (STR-PCR) DNA technology. The DNA profile developed from the sample(s) is compared to DNA profiles developed from individuals involved in the case to determine inclusion or exclusion of the person identified as a possible source of the profile in question. Statistical analysis provides weight or meaning to positive associations.
The DNA Casework Department provides Sexual Assault Evidence Collection Kits and Suspect Evidence Collection Kits to medical facilities throughout South Carolina to aid in standardizing collection of sexual assault evidence. All kits were developed in conjunction with medical, legal, and law enforcement communities.
When necessary in criminal cases, the DNA Casework Department can assist in arranging for private laboratories to perform DNA testing not performed at SLED such as mitochondrial DNA testing or Genealogy testing. The cost of testing performed by a private laboratory is generally the responsibility of the requesting agency.
Due to high demand for DNA analysis and in an effort to reduce the number of cases awaiting analysis, the SLED Forensic Services Laboratory, through the DNA Casework Department, may outsource analysis of some DNA cases to private vendor laboratories.
Vendor laboratories utilized for outsourcing must be accredited and must process casework samples in accordance with the FBI Quality Assurance Standards for Forensic DNA Testing Laboratories. These are the same standards that govern DNA analysis at SLED. Analytical data and final reports are reviewed by DNA analysts at SLED and qualifying DNA profiles are entered into the Combined DNA Index System (CODIS). Once the review process is complete, these reports are available via iLAB. Reports will be mailed if the submitting agency does not have access to iLAB.