Question

Base substitution mutations and frameshift mutations

If a segment of DNA were replicated without any errors, the replicated strand would have the following sequence of nucleotides:
5' - ACTACGTGA - 3'

Sort the following replicated DNA sequences by the type of point mutation each contains (frameshift, base substitution, or neither), as compared to the correct sequence shown above.

Sort the items into the appropriate name as frameshift mutation, base substitution mutation and or neither
5'-ACTCGTGA-3'
5'-ATTACGTGA-3'
5'-ACTACGTGT-3'
5'-ACTAAGTGA-3'

 

Answer 1

Frameshift Mutation

1) 5'- ACTCGTGA-3' = deletion of an "A" which shifts the reading frame from "ACT-ACG-TGA" to "ACT-CGT-GA"

2) 5'-ACTTACGTGA-3' = insertion of a "T" which shifts the reading frame to "ACT-TAC-GTG-A"

Base substitution Mutation

1) 5'-ACTAAGTGA-3' = substitution of a "C" for an "A" - does not change the reading frame and keeps the other codons the same = "ACT-AAG-TGA"

2) 5'-ACTACGTGT-3' = substitution of an "A for a "T" - does not change the reading frame and keeps other codons the same = "ACT-ACG-TGT"

Neither

none