1. DNA MUTATIONS

2. Causes
There are two ways in which DNA can become mutated:
Mutations can be inherited.
Parent to child
Mutations can be acquired.
Environmental damage
Mistakes when DNA is copied

3. EffecTS oF Mutations Most are neutral Some are harmful
Eye color
Birth marks
Some are harmful
Sickle Cell Anemia
Down Syndrome
Some are beneficial
Sickle Cell Anemia for Malaria
Immunity to HIV

4. Gene Mutations Point Mutations – changes in one or a few nucleotides
Substitution (same number or bases)
THE FAT CAT ATE THE RAT
THE FAT HAT ATE THE RAT

5. SUBSTITUTION
If a substitution changes the amino acid, it’s called a MISSENSE mutation.
If a substitution does not change the amino acid, it’s called a SILENT mutation.
If a substitution changes the amino acid to a “stop,” it’s called a NONSENSE mutation.

6. Gene Mutations
Frameshift Mutations – shifts the reading frame of the genetic message so that the protein may not be able to perform its function.
Insertion (extra nitrogen base)
THE FAT CAT ATE THE RAT
THE FAT HCA TAT ETH ERA T
Deletion (one less nitrogen base)
TEF ATC ATA TET GER AT H H

7. Which type of mutation is responsible for new variations of a trait?
Insertion, Deletion, Substitution (Missense)
Which type of mutation results in abnormal amino acid sequence?
Insertion, Deletion, Substitution (Nonsense & Missense
Which type of mutation stops the translation of the mRNA?
NONSENSE Substitution