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DNA Sampling Kit
A basic DNA Sampling Kit is recommended for preparing samples for
DNA analysis
and should include:
- Sampling equipment (scalpels, tubes, buffer),
- Disposable gloves
- Paper towel,
- Zip sealed bags,
- Swabs,
- A Permanent marker
Sampling kits for each of the sample collection types are available
from the Wildlife Forensic DNA Laboratory at cost (Kit
components, associated costs and order form).
SAMPLE SELECTION Selecting a Sample from a Kill Site
Gut Pile Tissues:
Samples associated with a kill site are most commonly the remains
of the animal.
The best samples from a kill site are brain, heart, and red muscle.
DNA in these samples will degrade in 3-4 weeks in warmer temperatures
until preserved. Heart and muscle samples should be reddish in colour
and this may require burrowing deeper into the tissue. Kidney, spleen,
liver, and stomach can be sampled if the sample is not older than
1 week. These organs undergo rapid enzymatic decay after 1 week
of environmental exposure to warmer temperatures. Hide samples with
attached reddish tissue can also provide sufficient DNA for testing.
Blood Stains:
DNA in a blood sample can undergo rapid degradation in less than
one week.
Blood frozen in snow and ice should be collected.
Blood stains at a kill site on leaves, dirt or rocks may be problematic
due to contamination by microorganisms. Samples may be placed in
a container with desiccant material to absorb any moisture.
NOTE: Animal remains and blood
which are frozen at the kill site during the winter months will
have extended periods of preservation.
Selecting a Sample Associated with
a Suspect
Samples commonly associated with a suspect are frozen meat samples
and blood.
Meat samples are often confiscated from the suspect's freezer. Animal
remains may also be present. See above for the most appropriate
samples for analysis.
Blood stains are found on two sources:
- Non-absorbent material, eg. metal and nylon
- Absorbent material, eg., cloth
Blood stains on absorbent material may be problematic as dyes
and chemicals in the material can contaminate a sample and inhibit
analysis.
Although some samples may be problematic for analysis, i.e. samples
with low yields or poor quality DNA, all samples associated with
the investigation should be submitted because the degree of DNA
degradation is dependent on several variables and the amount and
quality of DNA cannot be assessed until a DNA extraction has been
performed in the laboratory.
Sampling Instructions and Kit Availability
Sample Handling
To avoid contamination of a sample by the collecting officer or
by other animal samples associated with an investigation, the sample
collector should wear clean gloves to handle and prepare each sample.
Disposable sampling equipment are provided for sample preparation.
Preparation
of Meat, Organ and Hide Samples
Samples can be processed and shipped using preservative buffer:
- Label the sample tube using a permanent marker.
- Using clean latex gloves to handle the sample, with a clean
scalpel shave off a small portion from the outside of the tissue
and discard.
- Using a new clean scaplel, cut a piece of tissue approximately
the size of a 1 inch spaghetti noodle (7.5 mg) from the inside
of the tissue
- Add the sample to the buffer
- Repeat this process and place the second sample in the tube
containing buffer (provided).
- Tubes can be shipped at room temperature. Excess tissue sample
should be kept frozen at the respective facility.
Preparation
of Wet Blood Stains
Samples from a kill site are commonly found on leaves or rocks.
If the stain is large enough, sample the blood using a dry swab
without contaminating it with leaf material or dirt. Air dry the
swab for a few minutes, then place into the sealed tube provided
and ship at room temperature.
If the blood stain is small, save the leaves, etc., and place the
blood stain attached to the organic material into the desiccant
tubes. The sample will be stored and shipped dry.
Preparation
of Dried blood stains
Samples located on material such as clothing, knives, guns, etc.
should be shipped at room temperature in a well sealed package.
Blood stains may have to be cut or isolated from material.
If blood stains are located on an object that cannot be shipped,
collect the stain using a clean swab moistened with Phosphate Buffered
Saline (PBS), dry the swab and ship to the laboratory in a well-sealed
tube or container.
Preparation
of Hair and Feather samples
Samples should be kept dry and shipped at room temperature in envelopes
or a sealed plastic bag. DNA is isolated from the root of the hair
shaft and therefore it is extremely important that all hairs be
plucked not cut.
Preparation
of Processed meat samples
Samples for quantification such as sausages, or cooked meat should
be shipped in a cooler with ice. The entire meat sample should be
submitted to allow an accurate assessment of the species of origin
or the percentage of game animal tissue within sample. Freeze the
sample and ship in an ice-packed sealed cooler.
Preparation
of Whole blood samples
Blood from live-trapped animals can be collected on blotting paper.
Using the needles provided, draw blood from the specimen. Blot blood
from the animal onto leaflet inside the insert. Air dry for five
minutes and replace insert into envelope. DO NOT SEAL ENVELOPE.
Then place envelope into a sealed plastic bag with a desiccant pouch.
The blot should be shipped at room temperature.
The blot should be shipped at room temperature. If using a vacutainer,
the remaining blood should be frozen and kept at the respective
facility.
Preparation
of Fin Clips
Fin Clips can be removed and placed into vials containing a preservative
buffer. At least two fin clips
are recommended. Samples can be sent dry.
Preparation
of Bone samples
Bone samples from teeth, antlers and carcasses can be used for DNA
analysis. Most often bone samples are provided from historic samples.
A tooth will be removed from the skull to extract the DNA within
the root. The tooth will be cut at the base just above the root
allowing the rest of the tooth to be reinserted into the skull for
any subsequent morphological measurements.
Samples can also be obtained by drilling into a non-obtrusive portion
of the bone fragment with a minute drill bit and removing the bone
powder for DNA extraction. The largest bones will be targeted to
prevent damaging smaller bone specimens. We have successfully applied
this extraction protocol on a number of historic moose and elk antlers
and bowhead and North Atlantic right whale bones from the 1500s
with minimal impact of the actual specimen. Past studies have also
employed similar techniques for extraction of DNA from bones. Yang
et al. (1997) utilized a 3mm drill bit to obtain 0.15-0.5g of bone
dust from ancient skeletal specimens for successful DNA extraction.
Evidence Disposal Policy
All evidence will be disposed of 60 days following the completion
of a report for DNA analysis unless otherwise notified. Any requests
for the return of material such as clothing, knives, guns, etc as
well as processed meat samples must notify the Wildlife Forensic
DNA laboratory Forensic Scientist by email prior to the 60 days
and supply a shipping account number.
Shipping Samples/Continuity
of Evidence
Samples can be shipped via courier or registered mail. The packaging/coolers
should be sealed and signed by the investigator. If the samples
are frozen, they should be shipped in a cooler with ice packs with
the label "PLEASE KEEP FROZEN" clearly marked on the outside
of the cooler. Other shipments require double packaging to protect
against shipping damage. The seals will be examined following transportation
to ensure the package was intact during shipment. Samples submitted
to the laboratory for analysis are signed in as evidence and placed
in a secure evidence room. A case submission form must be sent with
the samples. These forms can be found HERE
Samples can be shipped to:
Dina Abdelhakim, Forensic Scientist
Wildlife Forensic DNA Laboratory.
Natural Resources DNA Profiling & Forensic Centre,
Biology Department, Trent University,
1600 East Bank Drive, Peterborough, Ontario, Canada, K9J 7B8.
Phone (705) 748-1011 ext. 1687.
Fax (705) 748-1132
E-mail: dabdelhakim@nrdpfc.ca
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