Forensic Biology can be broken down into two sub-disciplines, Serology and DNA.  The Michigan State Police Forensic Science Division has six laboratories with Forensic Biology Units.  Serology analyses may be conducted at laboratories located in Bridgeport, Grand Rapids, Grayling, Lansing, Northville, and Sterling Heights.  DNA analytical capabilities are located in laboratories at Lansing, Northville, and Grand Rapids.  Evidentiary items submitted to the Forensic Biology Unit are initially evaluated by the Serology sub-discipline.  Based upon a number of factors (type of crime, presence of a body fluid, suitability for DNA, investigative value, etc.), samples may be forwarded for further DNA testing.

Serology may best be described as the examination of bulk evidence (swabs, fabric cuttings, tools, various weapons, sexual assault kits, clothing, masks, etc.) using a variety of microscopic, chemical, immunological, and enhancement techniques to locate and characterize bodily fluids.  These bodily fluids typically include blood, semen/seminal fluid, saliva, urine, feces, and miscellaneous cellular material.  Results obtained from the Serology examinations may help establish if a crime occurred, actions taken during the commission of the crime and suitability for DNA testing.

DNA testing is conducted on samples submitted by the Serology sub-discipline to assist in the identification of individuals that may have left biological fluids at a crime scene.  The Michigan State Police Forensic Science Division first reported DNA cases in 1991 using Restriction Fragment Length Polymorphism (RFLP) technology.  Since 1999, DNA samples have been analyzed using the Polymerase Chain Reaction (PCR) to develop Short Tandem Repeat (STR) genetic markers and Capillary Electrophoresis separation.  This technology allows for the analysis of the 13 CODIS core STR loci and gender determining marker in a shorter period of time from smaller and/or degraded samples.

If DNA samples from potential donors are available at the time of testing, comparisons are made to DNA profiles from the evidentiary samples.  If a DNA match is declared, the probability of selecting an unrelated individual at random from the population with the same profile is generally measured in terms greater than one in a quadrillion.  DNA profiles from evidentiary samples may be entered into a DNA database (COmbined  DNA Index System) if certain eligibility requirements are met.  Subsequent searches may assist in associating an individual to a crime or linking crimes together.

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                                                                                                     310 Genetic Analyzer

          ABI Genetic Analyzer

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