As far as I know proteins are built by sequentially reading triplets of nucleotides.
But if at a certain point a nucleotide is inserted in the sequence, the following sequence of triplets is completely different.
For example: AATACGGTACCATTA ... AAT ACG GTA CCA TTA ... But inserting a nucleotide B at second place we get ABA TAC GGT ACC ATT ... Which is completely different.
However I know from theory that a single nucleotide insertion is not dangerous in most cases.
Could someone clarify my mind about this?