1. Mutations

2. This is not a mutation.

3. This is a mutation…

4. Introduction
Mutation: Changes in DNA that alter the genetic information.
Mutagen: Any substance/factor that can alter the DNA (ex. Smoking, U.V light, etc.)
There are 2 types of mutations:
Chromosomal Mutations
Gene Mutations

5. Mutations  changes in the sequence of DNA

6. Reproductive Cell Mutation
Location of Mutations
A. Mutation in Reproductive
Cells
1. Sperm and/or eggs
2. Passed to the next
generation

7. Somatic Cell Mutation B. Mutation in Body (Somatic) Cells
1. Any cell other than egg or sperm
cells
2. May/may not cause problems for the
individual with the mutation
3. All cells that come from the mutated cell
will have the mutation  may cause
cancer
4. Will NOT be passed onto their offspring

8. Gene Mutations A change in one or several nucleotides.
Substitution
A change in one or several nucleotides.
Point Mutation: One nucleotide is affected.
Ex. Substitution
Frame-shift Mutation: Many nucleotides are affected. Causes a “misread” of codons after the mutation.
Ex. Insertion & Deletion
Insertion
Deletion

9. Mutation Type: Nitrogen Base
1. Point Mutation – change in one nitrogen base
Original DNA – TCGATTTGA
Changed DNA – TCGATATGA

10. Example of Point Mutations

11. Mutation Type: Nitrogen Base
2. Frameshift Mutation – single nitrogen base is added or deleted; results in a shift in the codon reading frame
Original DNA – TCGATTTGA
Addition – TCGAGTTTGA
Deletion – TCG_TTTGA

13. Chromosomal Mutations
Change in the chromosome structure (location of the genes) or number of chromosomes
Original Chromosome – ABCDEFGHIJ
(letter = gene)
Deletion  ABC_EFGHIJ
**One or more genes is/are deleted

14. Chromosomal Deletion

15. Mutation Type: Chromosomal Mutations
Original Chromosome – ABCDEFGHIJ
Inversion  ABCFEDGHIJ
***Set of genes, on the same chromosome, are flipped/inverted

16. Chromosomal Inversion

17. Mutation Type: Chromosomal Mutations
Original Chromosome – ABCDEFGHIJ
Insertion  ABCDCDEFGHIJ
***One or more genes are re-inserted appear more than one time
***Inserted genes may come from
any chromosome

18. Chromosomal Insertion

19. Mutation Type: Chromosomal Mutations
Original Chromosome – ABCDEFGHIJ
& QRSTUVWXYZ
Translocation  ABCDUVWHIJ &
QRSTXYZEFG
**One or more genes are moved from one chromosome to another chromosome; they exchange places

20. Chromosomal Translocation

21. SO WHAT?
Any addition, deletion, translocation, or kind of mutation alters the sequence or order of ACTG in DNA or where they are found…which means…
YOU WON’T MAKE PROTEIN CORRECTLY

22. Possible Causes of Mutations
A. X-rays/exposure to radioactivity
B. Exposure to UV (ultraviolet) light
C. Exposure to harmful chemicals (mutagens)
D. Unhealthy lifestyle 
smoking, drugs, etc.