NAME __________________________________ Mutations Practice
(staff.fcps.net/einman/biology/MutationsWS.doc) Deletion, Insertion & Substitution
There are several types of mutation:
Frameshift: DELETION (a base is lost/deleted)
Frameshift: INSERTION (an extra base is added/inserted)
--- Deletion & insertion may cause what’s called a FRAMESHIFT mutation, meaning the reading “frame"
changes, thus changing the amino acid sequence from this point forward
POINT MUTATION/SUBSTITUTION (one base is substituted for another)
--- 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
Complete the boxes below. Classify each as Frameshift (Deletion or Insertion) or Substitution.
. (Hint:
Deletion & Insertion will always be frameshift
).
Original DNA Sequence: T A C A C C T T G G C G A C G A C T …
mRNA Sequence:
Amino Acid Sequence:
Mutated DNA Sequence #1 T A C A T C T T G G C G A C G A C T …
What’s the mRNA sequence? (Circle the change)
What will be the amino acid sequence?
Will there likely be effects? What type of mutation is this? ________________________________
Mutated DNA Sequence #2 T A C G A C C T T G G C G A C G A C T …
What’s the mRNA sequence? (Circle the change)
What will be the amino acid sequence?
Will there likely be effects? What type of mutation is this? ________________________________
Mutated DNA Sequence #3 T A C A C C T T A G C G A C G A C T …
What’s the mRNA sequence? (Circle the change)
What will be the amino acid sequence?
Will there likely be effects? What type of mutation is this? ________________________________
Mutated DNA Sequence #4 T A C A C C T T G G C G A C T A C T …
What’s the mRNA sequence? (Circle the change)
What will be the amino acid sequence?
Will there likely be effects? What type of mutation is this? _________________________________
