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Forensics Montana State University

VIEWS: 44 PAGES: 41

  • pg 1
									      By:
  Kalah Butler
    Alan Lee
 Reed Anderson
    Alan Lee
Twanria McKizzie
What we are Presenting:


    History of Forensics
     Forensic Methods
   Ethics and Human Error
  Non-Human DNA Analysis
                   Interesting video?



http://www.youtube.com/watch?v=SlZ5bF3opQ4
                        or
http://www.youtube.com/watch?v=vrNWFmT8SLo
Forensic Science:


            Forensic science is the intersection of law
            and science.
            forensics encompasses the accepted
            scientific methodology and norms under
            which facts regarding an event, artifact, or
            some other physical item (such as a corps
            or cadaver) are to the broader notion of
            authentication, whereby an interest
            outside of a legal form exists in
            determining whether an object is in fact
            what it purports to be or is alleged as
            being.
            This type of scientific evidence can be
            used to condemn the guilty and exonerate
            the innocent, and is also used in
            recreating crimes.
             • Photography:


• Modern photography began in the 1820s with
the first permanent photographs. This
invention gave a boost to the individual whose
main efforts were to fight crime.
•The invention of the camera made it possible
to depict criminals in custody so accurately
that the photographs were then used later as
references, where as before the mid 1800’s
hand drawn posters and verbal descriptions
were used to depict an criminals image.
•In the 19th century French photographer
Alphonse Bertillon was the first to approach a
crime scene with the systematic methods of an
investigator. He'd capture images at various
distances and take both ground level and
overhead shots.
•Photographs were and are still being used to
record evidence around an crime scene that
then allow forensic scientists and criminal
investigators to have an reference guide for
that particular crime scene.
Fingerprinting:   •Fingerprints offer an infallible means of personal
                  identification. That is the essential explanation for
                  their having supplanted other methods of
                  establishing the identities of criminals reluctant to
                  admit previous arrests.
                  •Fingerprinting has served all governments
                  worldwide during the past 100 years to provide
                  accurate identification of criminals.
                  •No two fingerprints have ever been found alike in
                  many billions of human automated computer
                  comparisons.
                  • In 1823, John Evangelist Purkinje, a professor of
                  anatomy at the University of Breslau, published his
                  thesis discussing 9 fingerprint patterns, but he
                  made no mention of the value of fingerprints for
                  personal identification.
                  • In 1892, Juan Vucetich made the first criminal
                  fingerprint identification. He was able to identify
                  Francis Rojas, a woman who murdered her two
                  sons and cut her own throat in an attempt to place
                  blame on another. Her bloody print was left on a
                  door post, proving her identity as the murderer.
           DNA Fingerprinting:

•Scientists can use DNA fingerprints to
identify individuals - just like actual
fingerprints.
• It is especially useful for paternity testing,
and for solving crimes.
•There is enough DNA in a small blood sample
to make a DNA fingerprint.
• Leicester University geneticist Alec Jeffrey
developed the method of DNA fingerprinting in
1985.
• One of the first uses of DNA Fingerprinting in
a criminal case in the United States was in
November 1987.
•Circuit Court in Orange County, Florida,
convicted Tommy Lee Andrews of rape after
DNA tests matched his DNA from a blood
sample with that of semen traces found in a        The first DNA Fingerprint
rape victim.
                                    Sources:


http://science.howstuffworks.com/crime-scene-photography.htm
http://www.onin.com/fp/fphistory.html
http://www.pbs.org/wgbh/pages/frontline/shows/case/revolution/wars.html
Introduction to Biotechnology: Chapter 8” Thieman and Palladino
History of Forensics

     By Alan Lee
 Narborough Village Murders
•The first reported use of genetic fingerprinting in a
criminal case.
•1983 in the United Kingdom
•Investigators matched a semen sample with that of a
similar rape/murder case.
•Police conducted first mass screening of DNA by collecting
5,500 samples from male population.
•Investigators came to a dead end, however a man was
overheard he had given a sample in the name of a friend.
•The sample was an exact match, the suspect confessed to
both crimes
    The Forest Hills Rapist
•First use of DNA evidence in the United States
•1987
•In 1988, Victor Lopez was tried for the sexual assault
of three women
•All the women said their attacker was black
•However, Lopez’s blood was tested against sperm left
at the scene and found to be a match.
•Despite the eyewitness testimony, Lopez was found
guilty
The O.J. Simpson Case
     The OJ Simpson Case
•Nicole Brown Simpson and her friend Ronald Goldman
were murdered at her Los Angeles home on June 12th of
1994.
•The prime suspect was her ex-husband, and former NFL
star, O.J. Simpson
•Forty five samples were collected and it was discovered
that the DNA found at the crime scene was that of O.J.
Simpson
•Defense attorneys attacked procedures used in collecting
the DNA.
•The defense alleged that contamination could have
occurred; at one point one witness admitted to
mislabeling a sample.
•This created enough doubt in the jury’s eyes, which led
to Simpson being found not guilty.
September 11th
               September 11
•Nearly 3000 people died as a result of the terrorist attacks
on September 11th, 2001
•Dangerous conditions at ground zero made it very difficult
for forensic scientists to determine the identity of victims
based on their remains.
•Most remains were small bone fragments and teeth
•Collection points were set up around New York City where
family members could make missing person reports as well
as donate items that may contain DNA of the victims.
•Single Nucleotide Polymorphism analysis was used to
identify victims. Out of the 3000 people who died, only
about 1700 were identified.
M-FISys
                      M-FISys
•Mass Fatality Identification System
•Software system created in the wake of September 11 th
attacks
•First software to combine STR, mtDNA, and SNP in an
integrated matter.
•Can be modified to be used in other disasters or in natural
disasters
•Altered, and used to identify over 800 individuals in three
months following the South Asian Tsunami
                          Work Cited
•   http://www.promega.com/geneticidproc/ussymp14proc/posterpresentations/
    Cash.pdf                      “M-FISys”

•   “Introduction to Biotechnology: Chapter 8”     Thieman and Palladino
Forensic
Methods
By: Rhys Andersen
                                            Collecting DNA
 • Sources: Blood, Bone, Hair, etc.
 • Sources for successful Identification:
     DNA from parent, sibling, child, or
     items used solely by the individual
     such as toothbrush or comb.




http://streetknowledge.f iles.wordpress.com/2009/02/dna460276.jpg   http://endtimesworldnews.punt.nl/upload/feds_dna.jpg
          DNA Markers
• DNA markers are know as Probes.
• DNA probes are used to search out and
  bind to complementary DNA.
• DNA markers represent most most
  basic for of DNA identification.




                         http://static.howstuffworks.com/gif/future-crime-markers.jpg
                               RFLP
              Restriction Fragment Length Polymorphism

• Restriction enzyme used to cut DNA at
  specific recognition points.
• DNA sample are ran through gel
  electrophoresis to separate fragments.
• DNA probes hybridize samples so that they
  can bind with Complementary DNA
  sequences.
• Different Lengths of DNA fragments are
  compared to source DNA.
• RFLP requires large amounts of DNA
  samples.


                                              http://homepage.smc.edu/HGP/images/rflp.gif
                                               PCR
                                Polymerase Chain Reaction



• Requires Small amount of DNA
• Utilizes Polymerase chain
  reactions to create millions of
  copies
• Amplified DNA is ran through
  gel and separation points are
  compared to source DNA.


                                     Kary Mullis
                                     accepting the nobel
                                     prize in 1993.
    homepage.smc.edu/HGP/tools.htm                         http://www.bio.miami.edu/~cmallery/150/gene/c7.20.7.pcr.jpg
http://www.dna.gov/basics/analysis/pcr
                               STR
                 Short Tandem Repeat Analysis


• Heightened level of accuracy
• Standard for technique used by the FBI
• Analyzes 13 specific short tandem repeat
  regions.
• Specific Polymorphs chosen for analysis
  their increased level of diversity.
• Additionally Polymorphs chosen are non
  coding, and not linked to traits or
  phenotypes.                                http://www.dna.gov/dna-databases/types/

• STR used to Develop CODIS Data base.
• CODIS, as of 2004 contained 2,132,470
  DNA profiles, and had led to 19,000
  matches.
         Mitochondrial DNA Analysis

• Used if non recoverable
  nuclear DNA exists.
• DNA is isolated from
  mitochondrial DNA or
  mtDNA.
• mtDNA is identical between
  mother and daughter.
• Applicable method even
  when all Nucleated Cellular
  Material has been degraded.

                           http://evolution.berkeley.edu/evolibrary/images/news/mitochondrialdna.gif
                       Y-Chromosome Analysis
        • Identical between father and son.
        • Y chromosome is passed directly from
          father and son, making Y-chromosome
          analysis extremely accurate for
          identification.




http://www.bio.miami.edu/~cmallery/150/mendel/c7.15.X.Y.jpg
Sources:
    Forensics
Ethics and Human Error
                     Ethical Issues
• Massive DNA tests are
  controversial
• Narborough murders: 5000
  men were called upon for
  blood samples (this is now
  illegal in the US and UNK w/o
  due cause
• Many people feel this is still an
  invasion of privacy
                Ethical Issues cont.
•   DNA-profiling databases
     – All states authorize computer-searchable collections of DNA, and many
        are registered with CODIS which is run by the FBI.
          • CODIS includes convicted offender’s DNA, and unidentified DNA
          • Some states have proposed DNA collection at birth, so, relatives
             can be identified
•   This allows identification of suspects, when no suspect exists
•   Opponents believe this profiling is invasive and is a violation of state and
    federal laws of unreasonable search and seizure
•   Proponents feel these databases are secure, and because samples don’t
    have names attached it is ok.
            Rules of Evidence:
                Five Standards for Court Eligibility

• Relevancy test: allows           • Marx Standard: The common
  anything thought relevant          sense rule. Court must
• Frye Standard: Evidence            understand and evaluate
  gathering technique has            evidence presented
  a general acceptance in          • Daubert Standard: Requires
  the scientific community           pre-trial hearings for scientific
• Coppolino Standard:                evidence, and must be
                                     described in a peer-reviewed
  allows technique if                journal
  adequate foundation can
  be laid, even if profession
  as a whole is not familiar
  with new method
Human Error


• Chain of Custody: requires collection of evidence be
  systematically recorded and access controlled
• Morgue Tables: Often have at least three different DNA types
  present, making obtaining an accurate sample hard
• Analysis: Technicians make errors during analysis all the time.
• Sanitation @ Crime Scene: a must: Sneezing, sunlight,
  improper storage, and mislabeling can all destroy evidence
  (DNA)
• DNA & Juries: DNA evidence must be presented so the jury
  can clearly understand the statistical validity of certain pieces of
  evidence. If the jury cannot understand the evidence it is usually
  thrown out.
                          Sources:
• “Introduction to Biotechnology: Chapter 8” Thieman and Palladino
Non-Human DNA Analysis/
      Conclusion

            By:
      Twanria Mckizzie
    Non Human DNA Analysis

• Not every analysis is of human identity, but profiles of
  animals and plants has been used.
• Manufactures can use DNA sequencing to help make
  distinctions between American and Asian Ginseng ; for
  quality control and protects American Ginseng products
              “Paternity” of Plants

• Ancestry of Cabinet Sauvignon grapes
• Wine purists believe hybrid grapes are inferior
• Scientists can examine the DNA cabinet sauvignon
  plants
• Found two other varieties : Cabernet Franc & Sauvignon
  Blanc
• This challenged the idea that the varieties of these plants
  that come from cross-breeding are inherently less
  valuable as wine grapes.
                 Animal Profiling
• Evidence has been used to form
  genetic profiles of animals
• Example Is a case in
  Pennsylvania
• DNA fingerprinting was used to
  prove that a hunter had illegally
  killed a bear.
• Authorities collected blood
  samples from the bear den and
  then compared it with samples
  from the check station
• Because of this the DNA
  Analysis investigators were able
  to find the hunter guilty.
• Investigators can use DNA profiling regularly for wild life
  management.
• They have been able to improve some techniques of
  DNA fingerprinting to prove that game has been taken
  against regulations.
   DNA Labels & Counterfeiting
• DNA labels can prevent counterfeiting and Piracy
• The labels of DNA authentication can place anything of
  value: expensive fine art, Sport memorabilia.
• The labels can be detected by using PCR or
  hybridization, so authenticity is verified
• Examples :
• 2003 super bowl, footballs were encoded with DNA
• Olympic licensed material
• An inspection of merchandise vendor in Sydney revealed
  that 15% of merchandise sold was counterfeit, which
  therefore contributed to 1 million dollars of lost sales.
                         Sources
• “Introduction to Biotechnology: Chapter 8” Thieman and Palladino

								
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