Can post-mortem blood be used for DNA profiling after peri

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
A controversial issue in forensics is if perimortem 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.

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.

Not supported by literature.

Previous studies have shown that blood
transfusion does not affect the DNA
profile of an individual, whether living or
dead.

Common to separate components of
blood and not use whole blood

Packed RBC- RBC that have been
separated from whole blood for
transfusion purposes

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.

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
http://en.wikipedia.org/wiki/Com
mon_iliac_vein
http://en.wikipedia.org/wiki/Psoas_
major_muscle

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.

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.

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.
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.


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 ºC for
digestion.

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?

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.
http://www.odec.ca/projects/2005/wa
li5s0/public_html/root.htm
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?


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,

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.

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.





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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