Based on the internet, consensus sequence is defined as the following. """ In molecular biology and bioinformatics, the consensus sequence (or canonical sequence) is the calculated order of most frequent residues, either nucleotide or amino acid, found at each position in a sequence alignment. It represents the results of multiple sequence alignments in which related sequences are compared to each other and similar sequence motifs are calculated. Such information is important when considering sequence-dependent enzymes such as RNA polymerase. """. So based on this definition, I thought that the consensus sequence might not exist. Is it correct? Many thanks in advance.
Why not? Please extend you thinking.