Forensic Biology

Examiners in the Forensic Biology Section routinely examine items of evidence for the presence of biological material. After the proper samples for comparison purposes are obtained, DNA analysis can be conducted on these stains, and conclusions can be drawn as to whether an individual can be eliminated or included as a possible contributor to the genetic material identified. In cases in which a suspect has not yet been identified or an identified suspect has been eliminated, the DNA profile obtained from the evidence can be entered in the DNA Data Bank and searched for possible matches to convicted offenders, arrestees, and/or other crime scene samples.  These searches can be conducted at the state and national levels.

The Section can also perform two forms of specialized DNA testing referred to as Y STR testing and Mitochondrial DNA testing.  Y STR testing will develop DNA profiles from males and is useful in some sexual assault cases where the amount of male DNA present may be low compared to the high amount of female DNA present in the evidence.  This form of DNA is passed on by fathers to all their biological sons.

Mitochondrial DNA is often conducted on human skeletal remains in an attempt to identify the deceased individual.  This DNA is passed on by mothers to all of her biological children.

Our primary duties are to:

  • Examine physical evidence for the presence of biological material
  • Conduct DNA analysis
  • Compare DNA from unsolved cases to a computerized database of DNA profiles from convicted offenders, arrestees, and other crime scene samples to provide possible investigative leads to law enforcement officers