Finish Part A of your Gel Electrophoresis Lab.

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Finish Part A of your Gel Electrophoresis Lab. 1.
Make sure you have everything done in red to the
left of the screen. (Grade for Part A) 2.
There are lab pages at your tables to help you
finish. 3. If you were not here for the lab,
come see me to set up a time to complete
it outside of class time. IN ABOUT FIFTEEN
MINUTES. 1. I will begin the pre-lab for Part
B- DNA Fingerprinting. 2. Your DNA/protein
synthesis test has been pushed to next
Thursday 2/23 because Part B will take up Friday
and Tuesday.review game Wednesday.
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DNA FINGERPRINTINGCSI

• Lab 6 Molecular Biology
• Part B

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Investigators were called to the scene of a
homicide. Found at the scene was a large amount
of blood. Blood typing revealed that not only was
the blood of the victim present at the scene, BUT
also blood from another person..assumed to be
the guilty party.
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Originally there were four suspects.
Two suspects had alibis that checked out.
SUSPECT 1
SUSPECT 2
SUSPECT 3
SUSPECT 4
At the time of the murder, suspect 3 was seen
being escorted out of a local Taco Bueno with two
other trouble-makers. Apparently making fun of
fellow Bueno patrons. Thats no bueno.
At the time of the murder, suspect 4 was already
in county, being held for his involvement in a
karaoke/brawl fiasco. (Its always the quiet
ones)
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Blood samples from the remaining two suspects
were drawn under court order and were found to be
of the same blood type as the mystery blood found
at the crime scene. The police have turned to
you and your fellow lab technicians to employ the
process of DNA fingerprinting in building a case
against one of the suspects.
Kill everybody ..enough said And how many
times have we heard, I will
stab you
Lets face it..he just looks guilty.
SUSPECT 1
SUSPECT 2
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With the exception of (young) identical twins, no
two people have the same DNA sequence.
Introns and epi-genetics (years of environmental
effects and amount of mitosis trials) cause great
differences between individuals genes.
Because of these things, peoples genes are
different sizes (the more base pairs, the greater
the Molecular Weight of an individual gene).
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Before DNA fingerprinting can be completed, the
genes of the individuals DNA are cleaved (cut)
with restriction enzymes

• For our lab, we have the cleaved genes from
• the crime scene (mystery person)
• Suspect 1 (we will call them Chris)
• Suspect 2 (we will call them Amazing)
• We will also run what is called a Standard DNA
  Marker

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Because the genes are different sizes (amts of
base pairs), they will move at faster and slower
paces, showing different bands for each
gene. What do you know about the genes that move
further away from the wells?
1
2
3
4
5
6
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If lane six shows the crime scene, who matches it?
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What do you notice that is different this time?
DNA is a slightly negatively charged molecule, so
it will travel toward the positive end. So make
sure your wells are next to the negative side of
the container before you begin.
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-
Lane 4 Suspect 2 Chaumont
Lane 3 Suspect 1 Chris
Lane 2 Crime Scene DNA Sample
Lane 1 DNA marker standard
This is a standard marker. It shows different
base pair sizes (sizes of genes), so that you can
approximate the base pair sizes of the bands from
the suspects.

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1. You can load the wells tomorrow dry or submarine.
2. You will pour the buffer solution the same as
   yesterday
3. Each DNA sample contains the genes and a dye (the
   dye is NOT used to stain the DNA, but it is
   lighter in mass than any of the DNA genes.so it
   is used as a marker to know when to turn off the
   electrodes. It will show as a blue line.
4. You will not see the DNA bands.just the blue
   line.
5. Tomorrow we will load and run our gels and store
   them in the fridge over the weekend.
6. On Tuesday we will stain our gels to show the DNA
   bands and ?measure the bands for base
   size (comparing it to the standard)
   ?measure distance travelled in mm
   
   ?and to see which suspect matches
   the crime scene DNA

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• First make a Table of Contents entry and write
  the title of this lab on the page you are
  using for Part B.
• Write the purpose for this lab
• Create four Data Tables like the one found at
  your deskone for each sample, so label them
  accordingly- ex. (one should be titled
  Standard, one titled Crime Scene
• I will give you the Length (base pair size) for
  each fragment in your Standards Table.

Lab 6, DNA Fingerprinting Part B
Purpose Identify the guilty suspect in a
criminal investigation by reading DNA
fingerprinting. Determine the size of unknown
DNA molecules.
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Fragment Distance Migrated from well (mm) Length of gene (approx of base pairs)
1 (top-closest to well)
2
3
4
5
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