DNA is a deoxyribonucleic acid that contains genetic information, necessary to the development of an organism and for the correct functioning of all its parts. It has an elix shape and it’s composed by two filament, which contain a sugar phosphate backbone and four nitrogenous bases: Adenine (A), which pairs with Thymine (T), and Guanine (G), which pairs with Cytosine (C) .
Referring to the DNA in forensic science, is possible to use it, once extracted by organic or not evidence, to link directly a suspect to the crime scene, inasmuch it’s an individual evidence, or rather, unique for each living being.This important feature of the DNA is very helpful to solve tough cases, which, without the aid of DNA analysis, would be unresolved.However, being very delicate, it’s fundamental be able to extract and preserve it paying attention to not contaminate the evidence, and risk to compromise the unrolling of the entire case. Once a possible source of DNA, as blood, is identified, it’s important, as next step, wearing always gloves, and photographing the evidence, collect it and put it in a ventilated box, in order to avoid the growth of bacteria on the biological sample. After have collected the sample, it’s necessary remove others organic remains, such as blood, using a sterile swab and distilled water. There are different sources of DNA but, since the case that we are analysing is more focused on blood, was used blood as example of organic remain.
Focusing more on the case, the DNA analysis, done on the tiny bloodstains found on Gary Dobson’s bomber jacket and on his bag had a crucial role in the Stephen Lawrence’s murder during the unrolling of the case. Despite the dimension of the blood evidence and the amount of it, somewhat reduced, the forensic scientists in charge were able to determine matches between the victim and the suspect.The DNA evidence were obtained thanks to modern techniques that permit to extract DNA samples even from small and apparently inconsistent evidence.
Referring to the DNA in forensic science, is possible to use it, once extracted by organic or not evidence, to link directly a suspect to the crime scene, inasmuch it’s an individual evidence, or rather, unique for each living being.This important feature of the DNA is very helpful to solve tough cases, which, without the aid of DNA analysis, would be unresolved.However, being very delicate, it’s fundamental be able to extract and preserve it paying attention to not contaminate the evidence, and risk to compromise the unrolling of the entire case. Once a possible source of DNA, as blood, is identified, it’s important, as next step, wearing always gloves, and photographing the evidence, collect it and put it in a ventilated box, in order to avoid the growth of bacteria on the biological sample. After have collected the sample, it’s necessary remove others organic remains, such as blood, using a sterile swab and distilled water. There are different sources of DNA but, since the case that we are analysing is more focused on blood, was used blood as example of organic remain.
Focusing more on the case, the DNA analysis, done on the tiny bloodstains found on Gary Dobson’s bomber jacket and on his bag had a crucial role in the Stephen Lawrence’s murder during the unrolling of the case. Despite the dimension of the blood evidence and the amount of it, somewhat reduced, the forensic scientists in charge were able to determine matches between the victim and the suspect.The DNA evidence were obtained thanks to modern techniques that permit to extract DNA samples even from small and apparently inconsistent evidence.
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