Practice question

Consensus sequence mathematically summarizes most common nucleotide at each position of alignment of numerous functionally related DNA motifs, such as promoters or transcription factor binding sites. Calculation counts base frequency across aligned examples and chooses majority residue to build idealized pattern that may not exist perfectly in nature. For instance bacterial -10 consensus TATAAT emerges from frequency analysis. Deviations from consensus correlate with reduced binding affinity and promoter strength. Consensus representation provides predictive tool for genome scanning and mutational analysis, distinguishing functional motif conservation from random DNA composition effectively.