The collection and processing of forensic evidence (Biological)

Collection of Biological Forensic Evidence

Biological evidence is any bodily materials present at a crime scene, on a victim or suspect, that could provide a link between individuals and the crime scene or victim.
Common types of biological evidence include body fluids (like blood, semen, saliva), hair, skin cells, and fibres from clothing.
Forensic investigators must meticulously document and collect all biological evidence without contamination. Proper handling, packaging, and storing of the evidence is crucial.

Fingerprints

Fingerprints are a commonly sought type of biological evidence, almost always left behind in a crime scene.
The uniqueness and permanence of fingerprints make them ideal for identifying individuals involved in a crime.

DNA Evidence

DNA can be extracted from several types of biological evidence like hair, blood, skin cells, and saliva. DNA profiling is then used to match evidence to a suspect.
Advanced techniques, such as Polymerase Chain Reaction (PCR) and Short Tandem Repeats (STRs) analysis, allow forensic scientists to generate DNA profiles even from small, degraded samples.

Bioinformatics

Once DNA profiles have been generated, they are compared with DNA databases. Matches can provide leads in investigations or confirm a suspect’s involvement.

Serology

Forensic serology involves the examination and identification of body fluids as potential evidence. Special tests can identify the contents and origin of a body fluid sample.

Remember, the accurate collection and processing of biological forensic evidence can often be crucial in solving a criminal case. However, it also presents challenges such as potential contamination, degradation of samples, and the necessity for advanced technologies and expertise.