If a cell mistakenly transcribed and translated a gene’s intron, the most relevant outcome would be:
Additional amino acids would be inserted into the chain.
Introns are non-coding regions of a gene that are usually removed during RNA splicing. If an intron is mistakenly included in the mRNA and translated, the resulting protein may have additional, non-functional amino acids, likely resulting in a malfunctioning protein. This can disrupt the function of the final protein product.