1. Mutations
Chapter 12-4

2. Any change to the genetic code Gene mutations:
What are mutations?
Any change to the genetic code
Gene mutations:
A change in one or a few nucleotides in a gene
Chromosomal Mutations:
a change in the number or structure of chromosomes

3. What are mutations? Gene mutations
1) point mutation (substitution): Change of 1 base into another resulting in a change in 1 amino acid in the sequence

4. Effects of substitutions
Some substitutions result in coding for same amino acid
Some change amino acid but doesn’t affect overall protein
Some change 1 amino acid and changes structure of entire protein

5. Sickle Cell Anemia
Normal hemoglobin
Sickle Cell
Hemoglobin

6. 2) Frameshift: Shift in the reading frame that causes every amino acid after the mutation to be different.
(Caused by Insertion or deletion)
Deletion
Insertion

7. Effects of Frameshift mutations
Good:
disables CCR5 HIV receptor which allows HIV virus to attack Immune cells
Mutations that allow evolution of species (survival of the fittest)
Bad: Causes severe disorders:
Tay Sachs
Chron’s diseas
Color Blindness

8. Chromosomal mutations:
What are mutations?
Chromosomal mutations:
A change in one or a few chromosomes
4 Types:
1) Deletion: Loss of part / all
2) Duplication: Segment is repeated
3) Inversion: Segment is reversed
4) Translocation: Segment breaks off and is reattached

10. Effects
Down Syndrome
Turners Syndrome