NCIt definition : A mutation occurring within the protein-coding region of a gene which results in a
shift in the reading frame of the encoded protein. Frameshift mutations often result
in the premature truncation of a gene product.;
Alternative definition : NCI-GLOSS: An insertion or deletion involving a number of base pairs that is not a
multiple of three, which consequently disrupts the triplet reading frame of a DNA
sequence. Such mutations usually lead to the creation of a premature termination (stop)
codon, and result in a truncated (shorter-than-normal) protein product.;