USING SCIENCE IN THE CAUSE OF JUSTICE
The Case of the Missing Alaskan
In December 2001,
a young woman was reported missing in Anchorage, Alaska, by her boyfriend—but
she was not to be found despite all efforts. Finally, in May 2003, her
mother submitted a saliva swab sample to the FBI for analysis; we determined
its nuclear DNA and mtDNA profiles and entered it our Combined DNA Index
System for use in the FBI’s National Missing Person DNA Database.
It was there, ready for matching, when hikers discovered the severely
decomposed remains of a body on Alaska’s Seward Highway that June.
First, though, another agency believed the remains might match its ongoing
arson case. It had a nuclear DNA profile developed from the remains—but
no match! Then the Alaska crime lab and the FBI’s nuclear DNA lab
got a hit between the mother’s nuclear DNA and the Alaska remains,
showing a possible biological relationship. Our lab conducted mtDNA analysis
on the remains, compared it to the mother’s profile, and found
the match. The remains were identified by the coroner, and the case was
So what on earth
is mitochondrial DNA (mtDNA) analysis?
process that determines mtDNA sequences in small or degraded evidence samples,
then compares them to the mtDNA of blood or saliva samples submitted from
a particular investigation (victims, suspects, or relatives of missing
persons) to determine whether or not they match.
When do you
When your evidence samples
don’t contain enough nuclear DNA (nDNA) for suitable analysis. Primarily,
we conduct mtDNA analysis on hair shafts that are recovered as evidence…and
on aged human remains, such as bones and teeth.
How often do
we use it? As often as we can, given our resources. Last year
we completed 283 cases. As of September 10 of this year, we have completed
414 cases, including cases from the National Missing Persons DNA Database.
How long does
each examination take? Considerable time, as exacting care must
be taken for each of our many cases: on average, about 7 months for a
complete turnaround time…but we continue to shorten the time without
Who does the
examinations? Currently, our Mitochondrial DNA unit is staffed
with 11 forensic mtDNA examiners (including four detailed to the National
Missing Persons DNA Database who analyze specimens from unidentified
human remains and relatives of missing persons) and 17 mtDNA biologists.
In addition, we are in the process of bringing more people and more labs
online: four regional mtDNA laboratories are in the works—in Arizona,
Connecticut, Minnesota, and New Jersey.
A bright future
for using science in the cause of justice. As these new laboratories
become operational during the next two years, the FBI will be able to
nearly double its ability to deliver no-cost DNA analysis to the criminal
justice community. And, incalculable, to bring resolution to the families
of missing and slain loved ones.
Analysis 2 Unit | FBI Laboratory
Graphic: Here is an example of nucleotide sequence
data generated by the 3100 Genetic Analyzer. An examiner carefully
analyzes each peak from both strands of the DNA molecule. An examiner
looks at over 600 of the building blocks from each sample.