1. Review:
Can you tell the story of protein synthesis?

2. Mutations

3. When do mutations affect the next generation?
Point mutations
single base change
base-pair substitution
silent mutation
no amino acid change
Due to “wobble”
missense
change amino acid
nonsense
change to stop codon
When do mutations affect the next generation?

4. Point mutation leads to Sickle cell anemia
What kind of mutation?
Missense!

5. hydrophilic amino acid hydrophobic amino acid
Sickle cell anemia
Changes the shape of the hemoglobin protein
One amino acid is different!
hydrophilic amino acid
hydrophobic amino acid

6. Mutations Frameshift shift in the reading frame insertions deletions
changes everything “downstream”
insertions
adding base(s)
deletions
losing base(s)
Where would this mutation cause the most change: beginning or end of gene?

7. mRNA processing must be accurate
No room for mistakes!
a single base added or lost throws off the reading frame
AUGCGGCTATGGGUCCGAUAAGGGCCAU
AUGCGGUCCGAUAAGGGCCAU
AUG|CGG|UCC|GAU|AAG|GGC|CAU
Met|Arg|Ser|Asp|Lys|Gly|His
AUGCGGCTATGGGUCCGAUAAGGGCCAU
AUGCGGGUCCGAUAAGGGCCAU
AUG|CGG|GUC|CGA|UAA|GGG|CCA|U
Met|Arg|Val|Arg|STOP|

8. Identify the mutation THE FAT CAT ATE THE RAT THE FAT BAT ATE THE RAT
How could you change this sentence to show each kind of mutation?
THE FAT CAT ATE THE RAT
THE FAT BAT ATE THE RAT
THE FAA TCA TAT ETH ERA T
THA FAT CAT ATE THE RAT
THE FAC ATA TET HER AT
THE FAT CAT
Nonsense Mutation (substitution)
Missense Mutation (substitution)
Insertion Mutation (frameshift)
Silent Mutation (substitution)
Deletion Mutation (frameshift)

9. What’s the value of mutations?