1. Get ready for a good day!!! (Get Hype!)
Unit 6
MUTATIONS

2. Title: DNA Mutations
“I do”

3. (5 minutes) Let’s Play Telephone.
What happened?

"The quick brown fox jumped over a lazy yellow dog eating a hamburger with no pickles.”

4. Agenda Bellringer (5min) Introduction (5min) Input (15min)
Group Work (25min)
Review (10min)
Independent Practice (20min)
Exit Quiz (10min)

5. Think – Pair - Share Read the following two sentences:
THE DOG BIT THE CAT
THE DOG BIT THE CAR
What happened when a single letter in the sentence was changed?
If you changed any other letter, will the sentence continue to make sense?
What would happen to the sentence if we were to delete the letter G?
You are a scientist, how would you describe this change you observed?
What would you name it?

6. What you just observed is
called a mutation!
Mutations are changes
in the genetic material.

7. A mutagen is something that causes a mutation.
What caused the “mutation” in your final product during the Telephone game?
A mutagen is something that causes a mutation.
Ex: radiation, chemicals, high temp.

8. Mutations in Body vs. Sex Cells
In sex-cells: can lead to changes producing offspring with new characteristics.
BAD: May result in embryo not surviving.
GOOD: May provide organism with an advantage. (EVOLUTION)
- In body cells: affect only the individual and may result in cancer.

9. A. Chromosome mutations
Chromosome mutations are changes in entire chromosomes
Sometimes a mistake happens during cell division which can lead to chromosome mutations, or even more damaging, can lead to something called non-disjunction.
A B C D E F G H
A B C E F G H
Deletion

10. Chromosome mutation
Nondisjunction is the failure of chromosomes to separate during the division of chromosomes in the sex cells.
Nondisjunction causes the genetic disorder Down Syndrome; the baby has an extra chromosome 21.

11. Chromosomal mutations

12. B. Gene Mutations produce changes in a single gene.
There are 2 main types: Point and Frameshift.

13. Read the following two sentences:
THE DOG BIT THE CAT
THE DOG BIT THE CAR
Where is the mutation? What happened to the last “codon” ? What word would you use to define what happened to the last base (letter) of that codon?
In science we call this a Point mutation (Substitution)

14. 1. Point mutation (substitution)
-A change in one base pair in a DNA sequence.
-A point mutation can cause an amino acid to change, which will change the structure of the protein being made.
Example: AUG=Met
AAG=Lys
-Only one letter was changed (the A to a U) and the entire amino acid changed (from methionine to lysine).

16. Nonsense mutations: result in a stop codon
STOP codons:
in RNA:
UAG
UAA
UGA

17. Point mutations in our lives!
Missense Ex: Sickle Anemia
Hemoglobin protein in red blood cells
strikes 1 out of 400 African Americans
limits activity, painful & may die young
Normal round cells
Misshapen sickle cells
Only 1 out of 146 amino acids 17

18. Point mutations in our lives!
-People with sickle cell anemia often experience a lot of pain and swelling and have trouble exercising.
-BUT, that’s not an excuse…
(Ryan Clark, a player for the Steelers)
Here is a picture of Ryan Clark, a player for the Steelers. He does not play at high altitudes because his condition is dangerous when playing in those conditions. But, he still plays in NFL. Together we can-whatever it takes- no excuses.

19. Read the following two sentences:
THE DOG BIT THE CAT THE DOB ITT HEC AT
What happened to the code above? What word would you use to define what happened to the codons?

20. 2. Frameshift mutation
-Frameshift mutation-adding or deleting nucleotides to a DNA sequence.
-A frameshift mutation is much worse than a point mutation because it causes the entire DNA sequence to be shifted over!
Example: DNA: ATTAAACCG
ATAAACCG
Delete this T

21. Frameshift Mutations
Crohn’s Disease is caused by a frameshift mutation.
It causes inflammation to the digestive tract.

22. Gene Mutations:

23. Missense (changes amino acid)
Types of Mutations in Translation
Point (letter gets substituted)
Frameshift (letter gets deleted/inserted)
Missense (changes amino acid)
Addition (letter is added)
Silent (does not change amino acid)
Deletion
(letter is deleted)
Nonsense
(Changes amino acid/stop codon)

24. Questions: Is this a point mutation or a frameshift mutation?
-It’s a point mutation because only one nucleotide changed!

25. Break the mRNA into codons!
GUAUUUGCGAUG GUA-UUU-GCG-AUG How many codons do I have? 4 codons

26. Questions: THE DOG BIT THE CAT THE DOG BIT THE CAR
Point or frameshift?
Point!
Why?

27. Questions THE DOG BIT THE CAT THE DOB ITT HEC AT Point or frameshift?
Why?

28. ATTENTION: Review in preparation for your Group practice

29. Use the codon chart to translate the codons into amino acids

30. Frameshift Mutations: How is this deletion?
AUGCGUGUAUACGCAUGCGAGUGA
MetArgValTyrAlaCysGluStop
Does this change the protein?
A LOT!
Mutation!
AUGCGUGUAUACGAUGCGAGUGA
MetArgValTyrAspAlaSerGA 30

31. Frameshift Mutations: How is this addition?
AUGCGUGUAUACGCAUGCGAGUGA
Does this change the protein?
A LOT!
MetArgValTyrAlaCysGluStop
AUGCGUGUAUACGUCAUGCGAGUGA
MetArgValTyrValMetArgValA 31

32. How is this a substitution?
Point Mutations
How is this a substitution?
THEFATCATANDTHEREDRATRAN
Does this change the sentence?
A LITTLE!
THEFATCARANDTHEREDRATRAN OR
THEFATCATENDTHEREDRATRAN 32

33. Point Mutations(Substitution)
Why is this missense?
AUGCGUGUAUACGCAUGCGAGUGA
MetArgValTyrAlaCysGluStop
Does this change the protein?
DEPENDS…
RADIATION!
AUGCGUGUAUACGUAUGCGAGUGA
MetArgValTyrValCysGluStop 33

34. Point Mutations AUGCGUGUAUACGCAUGCGAGUGA MetArgValTyrAlaCysGluStop
Why is this silent?
AUGCGUGUAUACGCAUGCGAGUGA
Does this change the protein?
Why not?
MetArgValTyrAlaCysGluStop
AUGCGUGUAUACGCUUGCGAGUGA
MetArgValTyrAlaCysGluStop 34

35. Point Mutations AUGCGUGUAUACGCAUGCGAGUGA MetArgValTyrAlaCysGluStop
Why is this nonsense?
AUGCGUGUAUACGCAUGCGAGUGA
Really destroyed that protein!
MetArgValTyrAlaCysGluStop
AUGCGUGUAUAAGCAUGCGAGUGA
MetArgValStop 35

36. Group Practice (25min)
Work with your group to solve your guided practice worksheet

37. Let’s quickly review what we’ve learned so far…

38. Why is the genetic code universal?
All organisms have DNA made of the same molecules.
DNA in every organism has the bases: A,T,C,G
Why are there similarities in the genetic code of similar organisms?
- Most organisms share a common ancestry

39. DNA Replication Unwind Unzip (Helicase) Start (Primase)
Attach bases (Polymerase)
Glue (Ligase)
DNA is semi-conservative:
At the end of the process, there are two, identical strands of DNA, each with part of the original strand and a newly created strand.

40. Central Dogma: DNA  RNA  Protein
DNA Replication= making an identical
copy of a DNA strand

41. Replication – 1 minute video

42. RNA polymerase moves along the DNA
TRANSCRIPTION:
RNA polymerase reads one side of the DNA template and strings together a complementary strand of RNA nucleotides.
The DNA helix winds again as the gene is transcribed.
DNA
RNA polymerase moves along the DNA

43. RNA differs from DNA in three major ways.
RNA has a ribose sugar.
RNA has uracil instead of thymine.
RNA is a single-stranded structure.

44. After transcription, the ribosomes have this foreign message that means nothing to them. So they must “translate” it

45. Translation Turns mRNA into an amino acid chain (protein)
It occurs in the cytoplasm using a ribosome

46. Mutations are changes in DNA that may or may not affect phenotype.
Some mutations affect a single gene, while others affect an entire chromosome.

47. Why don't all mutations result in visible change?
Not all mutations are harmful, some may be beneficial, and may not be visible (silent mutation).
Silent mutations occur because the same amino acid is created despite the error.

48. Independent Practice (20min) Complete: Silently Independently

49. Exit Ticket (10min)

50. Homework Finish Worksheet
Study for DNA Replication, Transcription, and Translation, and Mutation Unit Exam