Three Short Topics
18.1. Matching DNA to protein with frameshift errors
In Section 15.11.3, we discussed the canonical advice of translating any newly sequenced gene into a derived amino acid sequence to search the protein databases for similarities to the new sequence. This is in contrast to searching DNA databases with the original DNA string. There is, however, a technical problem with using derived amino acid sequences. If a single nucleotide is missing from the DNA transcript, then the reading frame of the succeeding DNA will be changed (see Figure 18.1). A similar problem occurs if a nucleotide is incorrectly inserted into the transcript. ...