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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.

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Presentation on theme: " A controversial issue in forensics is if peri- mortem blood transfusions can affect DNA profiling of the deceased.  Many people assume that the STR."— Presentation transcript:

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2  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.

3  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.

4  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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6  Common to separate components of blood and not use whole blood  Packed RBC- RBC that have been separated from whole blood for transfusion purposes

7  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.

8  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

9 http://en.wikipedia.org/wiki/Psoas_ major_muscle http://en.wikipedia.org/wiki/Com mon_iliac_vein

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11  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.

12  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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14  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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16  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.

17  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.

18  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?

19  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.

20 http://www.odec.ca/projects/2005/wa li5s0/public_html/root.htm

21  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?

22  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,

23  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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25  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.

26  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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