Forensic biology

[12][13][14][15] Subsequently, Albrecht H.O., a German chemist, developed luminol in 1928, which is used to detect trace blood stains at crime scenes.

Beyond forensics, PCR has made an impact on a wide range of fields, including disease diagnosis and virus detection.

[21][25][26][27] Nuclear DNA evidence can be recovered from blood, semen, saliva, epithelial cells and hair (provided the root is still intact).

[28][29] Once a potential source is identified, presumptive tests are conducted to establish if there is a specified biological presence (semen, saliva, blood, urine, etc.).

[36][37] A graph is constructed for the sample DNA comparing the presence of fluorescence (y-axis) to cycle number (x-axis) of the qPCR process.

This is then compared to a standard curve of the cycle fluorescence threshold (y-axis) versus the log of known DNA concentrations (x-axis).

In many cases, these may be older human remains, sometimes ancient, and the only options for DNA collection are the body's bone, teeth, or hair.

[45][43] Due to this type of inheritance, mtDNA is useful for identification purposes in forensic work but can also be used for mass disasters, missing persons cases, complex kinship, and genetic genealogy.

When a sample of mtDNA is severely degraded or has been obtained from an ancient source, the use of small amplicons can be used to improve the success of amplification during PCR.

[51][52] There was only circumstantial evidence otherwise against Ware so the admittance of mtDNA from hairs found in the victim's throat and at the scene were key to the case.

[52] In 2004, with the help of the National Center for Missing and Exploited Children and ChoicePoint, mtDNA was used to solve a 22-year-old cold case where the nuclear DNA evidence was not originally strong enough.

[2][56][57] The primary goals of anthropological involvement include identification and aiding in scene reconstruction by determining details regarding the circumstances of the victim's death.

[59][60] The identification of plant material is crucial in forensic botany, as it can provide a link between an individual and a crime scene, pinpoint the geographical location of missing bodies, or establish the post-mortem interval (PMI) of a human skeleton.

This field of study can aid in investigations related to wildlife crimes, such as poaching, smuggling, and illegal trade of birds and their feathers.

It is a specialized field that has been instrumental in helping law enforcement detect and solve cases in criminal and civil proceedings.

The use of forensic odontology became more popular in the 1960s with the establishment of the first instructional program in the United States at the Armed Forces Institute of Pathology.

They are responsible for performing autopsies and applying their knowledge of the human body and possible internal and external injuries to determine the cause and manner of death.

The results of forensic toxicology analyses can be used to determine the cause and manner of death, assess the role of drugs or chemicals in impairment or toxicity, and provide evidence in criminal or civil proceedings.

The field of forensic toxicology requires a thorough understanding of the pharmacokinetics and pharmacodynamics of drugs and chemicals, as well as the analytical techniques used to detect and quantify them in biological matrices.

These agents, which can be natural or genetically modified microorganisms, are intentionally disseminated to cause illness, death, or harm to humans, animals, or plants.

Forensic microbiologists compare the microorganisms isolated from infected individuals to known sources of infectious pathogens to identify the cause of an outbreak.

[75] It is important to note that biological agents used as weapons are often found in the environment, making it challenging to determine whether an infection is accidental or the result of a deliberate attack.

[73] One of the most notable cases of bioterrorism in recent history involved the mailing of at least four anthrax-containing envelopes in the United States in September and October 2001.

[76] However, advancements in PCR and whole-genome sequencing enabled scientists to collaborate with the FBI to identify the source of the letter spores.

Once the number of cases and definition of the attack has been established, the outbreak can be characterized by analyzing the time, place, and person affected.

[79] Currently, extensive research is being conducted to determine if there is a consistent microbial decomposition "clock" that could be used by itself or in conjunction with other techniques, such as forensic entomology, to help estimate postmortem intervals.

One research group has made significant progress in describing such a microbial clock and believes they are within two to five years of testing it in a real crime scene scenario.

Biological testing for cold cases, specifically homicides, encounters similar roadblocks as the SAKs - lack of funds or the DNA samples have not been properly stored; thus too much degradation has occurred for viable analyses.

In popular culture, forensic biology is frequently portrayed in shows like Law & Order, Hannibal, Bones, CSI, Dexter and Castle.

However thanks to Hollywood's depiction of forensic science, the analysis of biological evidence has fallen prey to the CSI Effect, which results in the public's perception of its capabilities being severely distorted and its limits blurred.