In a point mutation, one single base nucleotide (A, C, T or G) is replaced by a different one. This results in the change of one amino acid in the protein. (A minor change that may or may not affect the overall function of the protein) .a frameshift mutation, one or more base nucleotides are inserted or deleted from the sequence. This shifts the 3 basepair codons resulting in a change in the amino acid sequence that is coded. An entirely different protein (usually nonfunctional) is coded.