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Forensic Genetic Evidence & Limitations

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A) What are some of the unique circumstances of forensic genetic evidence?

B) Describe some of the limitations involved with processing forensic DNA samples?

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https://brainmass.com/biology/dna-chromosomes-and-genomes/forensic-genetic-evidence-limitations-153756

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A) What are some of the unique circumstances of forensic genetic evidence?
Ans : Different forensic tools are utilized in different circumstances. It can be outlined as follows:-
1. Blood sample :
a. Blood samples are collected and analyzed. Most tests used to identify a material as blood are based on the fact that peroxidase, an enzyme found in blood, acts as a catalyst for the reagent added to the blood and forms a characteristic color. For example, when benzidine is added to a solution made from dried blood and water, the solution turns blue. If phenolphthalein is the reagent, the solution turns pink. More specific tests are then applied to determine if the blood is human
b. All humans belong to one of four blood groups-A, B, AB, or O. These blood groups are based on genetically determined antigens (A and/or B) that may be attached to the red blood cells. These antigens are either present or absent in blood. By adding specific antibodies (anti-A or anti-B) the presence or absence of the A and B antigens can be determined
2. Handguns are used in most of the homicides. Ballistic analysis is an important part of the forensic tools in crime labs. Comparison microscopes, which make it possible to simultaneously view and compare two bullets, are an important tool for forensic scientists. When a bullet is fired, it moves along a spiral groove in the gun barrel. It is this groove that makes the bullet spins so that it will follow a straight path much like that of a spiraling football. The striations or markings on the bullet made by the groove and the marks left by the firing pin are unique and can be used to identify the gun used to fire any bullets found at ...

Solution Summary

Different forensic tools are utilized in different circumstances. It can be blood samples, ballistic analysis,comparison microscopes, Scanning electron microscopes, mass spectrometer and the gas chromatograph.

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