In DNA affinity purification, DNA from promoter regions thought to be bound by the protein is labelled (e.g. biotinylated) and bound to beads (or some type of matrix). The protein is then left to interact with DNA and eventually eluted. Bound protein will remain attached to beads. This can be detected through gel electophoresis. The protein can then be sequenced by mass-spectrometry. The techinque can be used to demonstrate binding of a purified protein, or to purify the binding protein from crude extract or a mix of proteins.

MSA can be used to align promoter regions and highlight regions of conservation that may be indicative of transcription factor binding sites.

Visual inspection of promoter region to identify putative binding sites based on previous knowledge