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7.4.4 Evidence Collection Teams
Most morgue operations place the DNA collection team near the end of the
examination line after the photographs and radiographs have been taken and
following the completion of the dental examination and autopsy. The chief
of morgue operations or medical examiner/coroner will direct DNA samples
to be taken in accordance with the scope of the investigation, as discussed
e a r l i e r.^30 Usually the postmortem team will take a single sample from rela-
tively intact remains to confirm or augment other identification methods.
Team members may also be required to select the best possible material from
each of numerous fragmented human remains in order to provide a primary
identification or the genetic basis for reassociation of body parts. Most fre-
quently, natural disasters tend to require the former approach to sampling,
whereas transportation accidents and terrorist events are more likely to have
a greater need for reassociation.
The ideal DNA sample collection team includes two to three persons pos-
sessing (1) training in general morgue operations, (2) a rudimentary under-
standing of DNA science, and (3) thorough familiarity with human anatomy.
They must understand the criticality of the anatomical description and the
unique numbering of samples, plus be able to handle a Stryker saw, tissue
forceps, and scalpel with skill and safety. Odontologists and anthropologists
are usually good choices for the collection team, but death investigators and
emergency medical personnel are good alternatives. The trauma surround-
ing the event and subsequent environmental conditions will adversely affect
the soft tissue first by fragmentation and later by decomposition. Although
skeletal muscle is an easy sample to collect at the morgue and relatively simple
to process at the laboratory, the condition of the remains may necessitate the
collection of samples of bones and even teeth instead. Clumps of hair, skin
flaps, and soft tissue that are predominantly composed of adipose tissue all
cause additional steps in laboratory processing and should be avoided when
possible.^30 The collection team must use sterile disposable supplies when pos-
sible and wipe all surfaces and clean nondisposable gloves, instruments, and
working surfaces with a 10% bleach solution between samples.
Tissue, bone, or tooth samples should be placed in a secure container
without any preservative. The collection teams at the Armed Forces DNA
Identification Laboratory have had greatest success using sterile 50 ml coni-
cal tubes with screw caps. Urine specimen cups may leak, glass containers
could break, and small plastic bags are subject to puncture. Conical tubes
with screw caps easily accommodate 5 to 25 g samples of soft tissue, bone,
or tooth, do not leak, and have a smooth exterior surface for handwritten
or adhesive labels. Plus, enforcing their use actually limits the amount of
sample that an overly enthusiastic anthropologist, odontologist, or pathol-
ogist can submit from a single source. This reduces the long-term storage