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Monstrous Mutations
Introduction:
Mutations are caused by changes in DNA. Knowing a few basic types of mutations can help
you understand why some mutations have major effects and some may have no effect at
all. The following are some of the types of mutations that can occur.
Substitution
A substitution is a mutation that exchanges one base for another (i.e., a change in a single
“chemical letter” such as switching an A to a G). Such a substitution could:
1. Change a codon to one that encodes a different amino acid and cause a small change
in the protein produced. For example, sickle cell anemia is caused by a substitution
in the beta-hemoglobin gene, which alters a single amino acid in the protein
produced.
2. Change a codon to one that encodes the same amino acid and causes no change in
the protein produced. These are called silent mutations.
3. Change an amino-acid-coding codon to a single “stop” codon and cause an incomplete
protein. This can have serious effects since the incomplete protein probably won’t
function.
Insertion
Insertions are mutations in which extra base pairs are inserted into a new place in the
DNA.
Deletion
Deletions are mutations in which a section of DNA is lost, or deleted.
Frameshift
Since protein-coding DNA is divided into codons three bases long, insertions and deletions
can alter a gene so that its message is no longer correctly parsed. These changes are
called frameshifts.
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For example, consider the sentence, “The fat cat sat.” Each word represents a codon. If
we delete the first letter and parse the sentence in the same way, it doesn’t make sense.
In frameshifts, a similar error occurs at the DNA level, causing the codons to be parsed
incorrectly. This usually generates proteins that are as useless as “hef atc ats at” is
uninformative.
Objective(s):
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
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To understand and observe different types of mutations.
To recognize and adapt to mutations
To observe how mutations effect survival skills
Materials Needed:
12 beads (per group of three students)
Blanket for the food
Table or desk
One cup (per group of three/four students)
20 popscicle sticks
Six pairs of goggles
Cotton
Stop watch
Large roll of duct tape or masking tape
String
Paper bag containing the letters A through I on slips of paper
Procedure:
1. Students should form groups of threes. Each student will simulate an animal that
can only digest peanuts (represented by plastic beads) as its food source.
2. Unfortunately, random mutations have produced some unusual characteristics in
recent offspring. Each group will find out what mutation they represent by
selecting a letter from the paper bag the teacher has provided.
3. The letter drawn will correspond to the characteristics listed in Chart 1. This
letter will also represent the letter of each group’s home location and storage cup.
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Chart 1
Letter drawn by
groups
Characteristic produced by mutation
A
Long fingernails (produced by popsicle sticks taped to fingers with
tape)
B
No fingers (produced by taping each hand closed)
C
Lack of peripheral vision (produced by putting on goggles and stuffing
cotton in the sides to prevent viewing from the side)
D
Hands fused together in front of body (produced by placing hands
together in front of body and holding them together)
E
Feet and ankles fused together (produced by keeping the ankles
tightly together)
F
No arms (produced by keeping the arms down to the side of the body)
G
Arms fused together behind the back at the wrists (produced by
placing arms behind the back and holding together)
H
Blind (produced by using blindfolds)
I
Normal (silent mutation so no phenotypic effect)
Each group should attain the proper materials and prepare itself to represent the
characteristic produced by the letter of the mutation selected from the paper bag. 1
group member will be timing and 2 will be collecting food.
5. Each group should begin the activity at the specified location in Figure A. The goals of
each group are to:
A. Gather the food (12 beads per group, 2 of each color)
B. Store the food for later use (place the beads in your letter-designated
container).
C. Retrieve the food at a later time (remove the beads from the container
and return with the beads to the home location).
D. Process and “consume” the food (sort the beads out by color and then
move them one at a time into the “eaten” container).
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6. “Peanut” Retrieval Procedure:
1. To begin the activity, each group should position itself at its specified home
location.
2. One member will start the stopwatch and one member will begin with food
gathering.
3. Group members should proceed to the blanket containing the “food” and gather 12
beads per group, 2 of each color. These 12 beads should then be transported to
the specified container.
4. The group member should return to their home location. At this point, the group
member will proceed back to the plastic container to retrieve its food.
5. Once the group has removed all 12 beads, it will return to the home location.
6. The group will process the food by separating the beads out into their individual
colors. Then consumer the food by placing it, one at a time into the “eaten”
container in the middle of the room.
7. Once the last bead has been placed in the “eaten” container, stop the time and
record how long it took for your group to achieve this with your specific mutation.
7. Record the time for your mutation on the board.
8. Create a data table and record the times for all mutations. Create a bar graph
displaying the data.
Conclusion/Analysis:
1. What was your group’s mutation and how did this mutation affect your retrieval,
storage, and consumption of the peanuts?
2. Which group spent the least amount of time with this activity? What was their
mutation?
3. If your group did not have a mutation, what do you think the outcome would be
compared to the groups with the mutations?
4. If this type of animal had a mutation that affected it in such a way that it had a
difficult time finding, retrieving and consuming food, and there was another animal
with no mutation that ate the same food, give a hypothesis to what you think would
happen to the population of the animal with the mutation? Give the reasoning for
your hypothesis.
5. For the sequence of DNA – AACTGATGCGCC – give an example of how the sequence
would change for each type of mutation.
a. Substitution
b. Insertion
c. Deletion
d. Frame Shift
e. Silent Mutation (Transcribe and Translate - Show the DNA, mRNA, and
amino acids for this one.)
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