Forensic Biology (DNA)
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Locating Body
Fluid Stains |
The DNA Unit analyzes physiological fluids, bone, tissue, and hair. The three most commonly examined materials are blood, semen, and saliva. Examinations usually involve the identification of the material (as blood, semen, etc.), species determination and genetic marker profiling (typing in multiple loci) using DNA analysis.
Current DNA typing methods (PCR or Polymerase Chain Reaction) can be used not only to analyze very limited samples, but have enormous discrimination power. The chance that two people have the same DNA profile, excluding related individuals, can be as low as one in several billion with these types of analyses.
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Processing Stains
for DNA Typing |
An additional examination which deals with blood but is not strictly a forensic biology function, is bloodspatter interpretation. This technique is useful primarily in the field, and occasionally in the laboratory. The careful examination of bloodstain patterns may provide some information on how they were deposited, thus assisting in the reconstruction of the crime.
The information that is commonly developed by a bloodspatter
analysis includes determining the angle and direction at which the blood struck the surface, and some information as to the force of the action which caused the blood droplets to be produced.
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