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DNA Keychains
This project is a great way to teach kids the structure of DNA in a fun, artistic,
hands-on way.
Curriculum/State Standards
Describe the structure of DNA and the
way that DNA functions to control protein
synthesis
Overview
The activity will allow students to
understand and visually create a model
strand of DNA which they can use to
understand the replication, transcription,
and translation process.
• Students will be taught to use the
materials given to create a replica
strand of DNA. This is a weaved beaded
structure with a special sequence to show
how DNA is connected. After a completed
project, the student will use the model
in additional extended learning activities.
They will use their DNA keychain codes to
produce strands of RNA and subsequently
the amino acids that it codes for. The
students will understand the significance
of the sequence in their DNA and how
important it is to create a correct strand
of DNA. They will also be able to keep
their creations and use them as keychains
or holiday ornaments.
Objectives
The students will create accurate model
representations of DNA that allow them
to apply principles of transcription and
translation into proteins.
The students will experience how the
formation of strands of DNA affects the
types of amino acids and proteins they
will code for.
The students will understand the structure
of DNA and be able to relate it to its
function.
Materials
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GRADE LEVEL
1 key ring
40 Large “Pony Beads” – 2 different
colors (sugar and phosphate)
20 Small “Pony Beads” – 4 different
colors (nitrogen bases)
2 – 8 in piece of 28 gauge wire
1 – 12 in piece of 28 gauge wire
Readiness Activity
none
Strategies/Activities
directions and activity taken from
DNA Jewelry activity on http://www.
accessexcellence.org/AE/AEC/AEF/1995/
ross_jewelry.php or http://sciencespot.
net/Media/Genetics_DNAKeychainGuide.
pdf
Step 1: Decide which colors you want
to use for your model (you will need to
choose beads of six different colors two different colors for the sugars and
phosphates, and four different colors for
the base pairs.
Step 2: To make a keychain, cut two 15
cm (6”) strands of wire. Twist two wires
together at one end to prevent beads
from slipping off as you string them.
These strands of wire will be the helixes,
or “uprights” of your DNA model.
Step 3: String an equal and even number
of beads of alternating colors onto each
of the wires, to represent alternating
sugars and phosphates. Make sure to
start with the same color bead on each
wire. When you have strung the beads
on each of the wires, twist a loop at
the tops of the “uprights” separately to
prevent the beads from falling off. Use a
minimum of 26 beads for the basic 2 inch
molecule. (when twisted) (Leave one
THIS WINNING PROJECT IDEA SUBMITTED BY:
Amy Bishop
Clackamas Middle College
Happy Valley, OR
7-12
2
HOURS
$200
TOTAL BUDGET
DNA Keychains
....continued....
inch of “slack” at the top. If you
bead right to the top, it’ll be very
difficult to wire the bases.)
Step 4: Cut 30 cm (12”) of wire
and fold it in half to make an
elongated “U.” Next, string and
center two different colored
beads on the wire (or each wire,
for earrings) to form the first
“rung” or pair of nitrogenous
bases.
Step 5: Thread each end of the
wire with the “bases” beads
through the third and fourth
beads from the bottom of each
of the sugar and phosphate
“uprights” and pull tight. You’ve
made the first rung. Be sure that
the “u-wire’s” ends are even.
Step 6: Pull the ends of the bases
wire into the center of the ladder
and thread two more bases onto
one side of the bases wire and
take the other bases wire and
thread through the two justthreaded bases to make rung at
a right angle to the uprights. ***
Important!! The bases wires go
through each other in opposite
directions.*** (These additional
complementary bases can be
either the same or different
colors from the first two sets of
bases you used, depending on
your personal preference.)
Step 7: Continue threading the
bases wire up through the next
sugar and phosphate on each
“upright.” Now add two additional
complementary bases to the
bases wire as you did in Step 6.
(At the end of this activity, you
will use whatever combination
of bases you decided on to
determine the amino acids coded
for in your model.) Thread the
bases wire through the next
sugar and phosphate set and add
another base pair.
Steps 5-7 repeat!! Basic pattern
is: Up two on both sides, Add two
in the middle, Cross through the
two in the middle, Up the next
two on both sides. And again,
and again, and again...
Step 8: Repeat steps 6 and 7 until
you have attached alternating
base pairs to each sugar and
phosphate set of the “uprights.”
You should do at least twelve
base pairs to have a large enough
molecule to twist (and later
translate)
Step 9: Twist all of the wires at
the top of the ladder together.
You can twist and cut closely or
finish with one last pony-bead or
E-bead around the point where
the wires form the model and
the keychain or earring holder
connect. If the molecule is loose,
untwist the bottom two wires
and gently pull on each . This will
tighten the sides and make the
bases perpendicular to the sides.
Retwist together and trim after
tightening. (Not too tight because
you still need to twist into a
double helix!)
Step 10: Twist your model into
the Double Helix. Create a “key,”
assigning each color of bead a
part of the DNA, paying special
attention to which bases bind
together.
Added step – use hot glue gun
to secure loose ends of wire and
make them less sharp.
Culminating Activity
Using the DNA keychain and they
“key” that the students made for
their DNA,
1. Have each student write out
their DNA sequence.
2. Replicate their DNA on paper.
3. Have them make RNA
from their DNA on paper.
(transcription)
4. Finally, have them translate
their DNA to amino acids. (there
should be at least three amino
acids they make from their
keychain)
a. You can also have them
“mutate” or frameshift their DNA,
by having them change one of
their base pairs to something
else to see what would happen to
their DNA sequence if a mutation
occurred.
Evaluation Method
Students will be evaluated on
their knowledge of the structure
of DNA and how it correlates to
RNA and amino acids by a unit
test or quiz