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Published byEverett Booker Modified over 9 years ago
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A controversial issue in forensics is if peri- mortem blood transfusions can affect DNA profiling of the deceased. Many people assume that the STR profile generated will be from the transfused blood instead of the deceased individual’s blood. Hypothesized that donor leucocytes in administered blood will be detected in recipient blood.
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Other biological samples such as plucked hair or deep muscle are required for DNA profiling. Leads to a higher cost and more time required to process samples.
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Not supported by literature. Previous studies have shown that blood transfusion does not affect the DNA profile of an individual, whether living or dead.
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Common to separate components of blood and not use whole blood Packed RBC- RBC that have been separated from whole blood for transfusion purposes
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Due to this persistent assumption, this study tests whether STR profiling of a dead individual’s blood can be performed if the individual received large amounts of peri-mortem blood transfusions. In addition, the affect of organ transplantation of DNA profiling was tested.
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Five cases of deceased individuals who received massive peri-mortem blood transfusions were used to collect samples for DNA profiling. Blood was collected from the iliac vein and samples were collected from psoas muscle tissue and plucked head hairs
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http://en.wikipedia.org/wiki/Psoas_ major_muscle http://en.wikipedia.org/wiki/Com mon_iliac_vein
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Performed theoretical experiment to determine how much donor DNA needed to be present in order to be detected in blood. Five units of leucocyte-depleted packed RBCs in additive solution were donated. DNA extraction was performed and no DNA was detected using either quantification or STR profiling.
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Human dermis fibroblasts were obtained from live cell culture grown from a donated breast reduction surgical specimen. Serially diluted to 0, 1, 10, 100, 1000, and 10,000 cells and added to 200 μL aliuots of RBC concentrate.
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Control genomic DNA K562 was purchased from Promega. Serially diluted to 0, 0.01, 0.1, 1, 10 and 100 ng free genomic and added to blood cells.
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The Blood Transfusion Service in the UK states that leucocyte depletion should be a minimum level of 99% so components contain 5x10^6 leucocytes per unit, which is about two cells per microliter. This level could not be detected in this study.
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DNA was extracted from post-mortem blood using the QIAamp DNA Blood Mini Kit and from muscle and liver using the QIAamp DNA Tissue Mini Kit. Ten plucked head hairs were washed with sterile water and ethanol, and put in a tube with lysis buffer and proteinase K then incubated for 24 hours at 37 º C for digestion.
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DNA from hair was purified using phenol/chloroform/isoamyalcohol and then Microcon concentration. How do you get DNA from hair? Did they extract from the root or the hair shaft?
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Small amounts of DNA can be extracted from your hair. When hair grows, the root is supplied with nutrients and cells at the bottom of the hair follicle are constantly dividing and forming new hair material. Then, program cell death takes place as the hair grows, resulting in destruction of organelles.
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http://www.odec.ca/projects/2005/wa li5s0/public_html/root.htm
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Decomposed nuclei can be found in the hair shaft. Sufficient DNA can be extracted from hair root. Difficult to isolate DNA from hair shaft because it contains mostly highly degraded DNA from pycnotic nuclei. Mitochondrial DNA?
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DNA profiling was performed on DNA extracted from hair, blood, and muscle from the deceased individuals. Plucked hair was used as a reference to compare the other materials to. Previous studies have shown DNA profiling of plucked hairs is not affected by many of the same issues in this study,
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In all five cases, the DNA profile was the same for the plucked head hairs and post-transfusion blood samples. The only exception was the liver case where the DNA profile showed a mixture of two DNA sources. Hypothesized to originate from the donor organ, but this information not available.
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The current literature is supported by this study by concluding that blood samples from recipients of massive blood transfusions can be used for DNA profiling. In addition, blood can be collected from recipients of whole organ transplants, but this area needs to be investigated further.
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Graham, E. A. M., Toskos, M. & Rutty G. N. (2007) Can post-mortem blood be used for DNA profiling after peri-mortem blood transfusion? Int J Legal Med, 121: 18-23. http://www.odec.ca/projects/2005/wali5s0/pu blic_html/root.htm http://en.wikipedia.org/wiki/Common_iliac_vei n http://en.wikipedia.org/wiki/Psoas_major_musc le Muller, K., Klein, R., Miltner, E. & Wiegand, P. (2007) Improved STR typing of telogen hair root and hair shaft DNA. Electrophoresis, 28: 2835f.
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