DNA on Trial PBL in Practice

1
DNA on Trial - PBL in Practice

• Group 6 - Orchid Project Summer Institute
• John Fisher (facilitator), Arlene Getz, Diane
  Pollock, Stacie Sheffie, Tim Taylor, HsingChi
  Wang
• CCMB

2
Investigation of a Crime Scene

• We met with Detective Marshall White of the
  L.A.P.D. Devonshire Division. We then began to
  learn the step-by-step procedure for
  investigating the scene of a crime.
• Next, we read the written report of the crime.
  (FACTS)
• It was necessary for us to become acquainted with
  the suspects and their activities. (IDEAS)
• We examined the crime scene which included,
  taking notes, looking for things out of the
  ordinary, identifying point of entry/exit,
  cataloging evidence, taking measurement and
  photographing exhibits.

3
Blood Typing

• Mark Mayo walked us through the process of
  identifying blood types A,B,AB,O and Rh/-
• Using a kit, we identified the blood type of each
  of our five suspects.
• Next we typed the blood samples found at the
  crime scene.
• We then compared the blood samples found at the
  crime scene with those of our five suspects.
• The process of blood typing, coagulation, and
  the many different proteins contained in ones
  blood is fascinating!

4
Hair Analysis

• The analysis of hair can be broken down into
  three basic criteria for identification color,
  diameter or thickness, and fluorescence.
• Pablo Bringas showed us how to use a dissecting
  microscope to examine the color of our suspects
  hair samples.
• Next, we used a standard compound microscope to
  measure the diameter or thickness of each hair
  sample.
• Finally, we looked through a fluorescent
  microscope to measure the amount of oil in the
  shaft of the hair.

5
DNA Fingerprinting

• We learned that all living creatures have a
  unique protein sequence, or DNA. Nasrin Bahari
  and Michael Mogass assisted us in preparing the
  DNA samples of our suspects for analysis.
• We made an agarose gel to house the DNA for
  charging.
• We prepared the DNA samples and loaded them into
  a gel box and applied an electric charge. This
  forced the pieces of DNA to separate according to
  mass.
• Finally the gel documentation camera using UV
  light allows us to read the bands of DNA pieces,
  and then compare our suspect samples to that of
  the crime scene.

6
PBL - Our Experience

• The process of solving a burglary led us to many
  different aspects of learning forensic science.
  This experience afforded us the opportunity to
  work collectively and individually in attaining
  new knowledge. This new knowledge ultimately
  benefited our group goals. While each new idea
  didnt satisfy our desire for knowledge, it
  served as a springboard for new learning needs.
  In conclusion, IT WAS AN INTELLECTUAL FEAST!!!!