In a frameshift mutation, what effect does the addition or deletion of a base have on the amino acid sequence?

In a frameshift mutation, the addition or deletion of a nucleotide base shifts the reading frame of the genetic code. Since the genetic code is read in sets of three nucleotides (codons), introducing an extra base or removing one disrupts this grouping. As a result, all codons downstream of the mutation will be altered because they will be read differently. This shift can lead to changes in the entire amino acid sequence from the point of mutation onward, potentially resulting in a completely different protein that may be nonfunctional. This alteration underscores the significance of maintaining the correct reading frame in gene expression.