1. Dr. Doodle Donley’s Case
Investigated by: The Crime Busters
Detectives: Monica Mah, Morgan Gray, Emma Dugan and Tiffany Shyu
Photo: 4/2/14

2. Background/Tests Taken: How to Analyze Data
Photo: 4/2/15

3. ELISA Test Information:
What is an ELISA test?
Enzyme Linked ImmunoSorbent Assay
What is it used for?
Track disease outbreak
Antigen Detection (Direct Test)
Antibody Detection (Indirect Test)
Photo: 4/2/15

4. How Does ELISA Test Work?
Used an indirect ELISA test
Tests for antibodies
Antigen bonds to plastic wells
Add serum (primary) samples
Serum with antibodies attach to antigens
Remove excess liquid
Plastic microplate wells
Antibodies
Antigens
Photo: 4/2/15

5. How Does ELISA Test Work?
Add HRP-labeled secondary antibodies
These will bind to the antibodies that were bound to the antigens
Remove excess liquid
Rinse out unbounded antibodies
Add enzyme substrate
Positive tests change color
Negative tests stay clear
HRP-labeled Antibodies
Antibodies
Antigens
Photo: 4/2/15

6. ELISA Test: Works: Only if you have enough viral concentration
Can Be a False Negative/False Positive
Can be cause of cross contamination
A false reading in too faint of color
Usually tested multiple times
Photo: 4/2/15

7. Fingerprint Information:
What is a Fingerprint?
A mark left by a person’s finger that is unique and can be used to identify the person
What are the different types of fingerprints?
Visible: left by fluids (blood, paint, ink); visible to naked eye
Molded: left in a soft medium
Latent: left on smooth surfaces and made by natural oils and sweat from the finger; not visible to naked eye
Photo: 4/2/15

8. How to Find Fingerprints?
Powder:
Brush powder in a circular motion
Take photo
Lift print with clear tape
Chemicals:
Spray chemical (Iodine, ninhydrin, silver nitrate) to make print visible
Photo: 4/4/15

9. How Do You Find Fingerprints?
Cyanoacrylate Fuming:
Pour super glue on metal plate
Put plate, object with print, and
heat source in an airtight container
Fumes for super glue reveal fingerprint
What next?
Run fingerprints through the Automated Fingerprint Identification System (AFIS)
Photo: 4/4/15

10. Lip Print Information:
What is a lip print?
A mark left by a person’s lips; Like fingerprints lip prints are unique to each individual
What are the different types of lip prints?
Type I: Clear-cut Vertical Groove
Type I’: Partial-length Groove of Type I
Type II: Branched Groove
Type III:Intersected Groove
Type IV:Reticular Pattern
Type V: Other Patterns
Photo: 4/2/15

11. How to Test Lip Prints: Comparing lip prints Photograph suspect’s lips
Have suspect make lip prints
Use a roller finger printer
Collection of lip prints at the crime scene is the same as collection of fingerprints
Photo: 4/4/15

12. DNA Fingerprinting Information:
What is a DNA Fingerprint?
Test to identify genetic information
Examines a person’s unique sequence of DNA base pairs
What is it used for?
Test for familial relationships
Identify diseases
Solve crimes
Photo: 4/2/15

13. How to Get DNA Fingerprint:
Obtain Sample
Can be from hair, blood, saliva, etc.
Only a small amount is required
Separate DNA from cellular material
Restriction enzymes cut DNA into smaller pieces
Produces blunt/sticky ends
May result in fragments called restriction fragments length polymorphisms (RFLP)
Pur RFLP into agarose gel
Photo: 4/5/2015

14. How to Get DNA Fingerprint:
Use gel electrophoresis
Fragments are sorted by size
Smaller fragments move farther across the gel
DNA becomes single stranded
Nucleotides are free
Transfer fragments onto nylon (blotting)
Wash radioactive probes over nylon surface
Place photographic film on top of nylon surface
Wherever attached to RFLP, probes will leave marks
Dark marks will appear
Compare marks to sample
Photo: 4/5/2015

15. Gel Electrophoresis: What is Electrophoresis? What is it used for?
Process to separate and analyze macromolecules
Can be used on DNA, RNA, proteins, etc.
What is it used for?
Forensics: DNA Fingerprint
Molecular Biology: Separate DNA and RNA to study
Genetics: Prepare DNA for genetic engineering
Photo: 4/5/2015

16. Polymerase Chain Reaction (PCR):
What it does:
Copy DNA outside of a cell
Generates thousands to millions of copies to a particular DNA sequence
What the DNA copies used for:
DNA fingerprinting
Genome mapping
Diagnosis of genetic disorder
Photo: 4/5/15

17. Steps for PCR: Denature the DNA/Separate Strands Heat: 95-96 C
Disrupt hydrogen bonds to separate
Add primers
Heat C
Add DNA Polymerase
Heat 72 C
Repeat steps 30 or more times
Results in thousands to millions of a copy DNA sequence
Photo: 4/5/15
Photo: 4/5/15

18. Blood Typing Information:
What is blood typing?
Four types of blood (O, A, B, AB)
A + or - is added to blood type to signify presence (+) or absence (-) of the Rh factor
What is it used for?
Safe blood transfusions
Rare blood types/ blood proteins can support whether a person is guilty/innocent of a crime
Photo: 4/5/15

19. How to Test Blood Types:
Adding specific antibodies to blood samples can determine whether the presence of the A or B antigen
Using the chart to
the right we can
determine the
blood type
Blood type
Antigens Present A B AB
A and B O
None
Photo: 4/5/2015

20. Crime Scene
Photo: 4/2/15