Chromatin immunoprecipitation-sequencing (ChIP-seq) is widely used to find transcription factor binding sites, but suffers from various sources of noise. Knocking out the target factor mitigates noise by acting as a negative control. Paired wild-type and knockout
experiments can generate improved motifs but require optimal differential analysis. We introduce peaKO—a method to automatically optimize motif analyses with knockout controls, which we compare to two other methods. PeaKO often improves elucidation of
the target factor and highlights the benefits of knockout controls. It is freely available at https://peako.hoffmanlab.org.M.Sc
