Why are frameshift mutations likely to be more detrimental than point mutations, in which a single pyrimidine or purine has been substituted?

Key Concepts

Frameshift Mutations

Frameshift mutations occur when nucleotides are inserted or deleted from the DNA sequence, altering the reading frame of the genetic code. This shift can lead to a completely different translation of the amino acid sequence downstream of the mutation, often resulting in nonfunctional proteins or premature stop codons.

Point Mutations

Point mutations involve the substitution of a single nucleotide in the DNA sequence, which may result in a silent, missense, or nonsense mutation. While they can affect protein function, the impact is generally less severe than frameshift mutations, as they typically alter only one amino acid or have no effect at all.

Protein Function and Stability

The function and stability of proteins are highly dependent on their specific amino acid sequences. Frameshift mutations can disrupt the entire protein structure, leading to loss of function, while point mutations may only cause minor changes. Thus, frameshift mutations are often more detrimental due to their potential to create entirely nonfunctional proteins.