Deletion mutation

A deletion is a type of mutation that occurs when a single nucleotide, or sequence of nucleotides has been ommitted from the DNA sequence. The effect of this is a frameshift mutation, which causes radical changes to the protein that is translated and it invariably leads to a truncated protein. This is because the amino acids used to form proteins are coded for by a sequence of three non-overlapping bases in the DNA sequence, therefore if one or more of the bases is deleted, every triplet code following this will have shifted and will generate a completely different amino acid. The resulting protein will be inactive as it will no longer be the correct shape for its original function.