Cappable-seq is a method, developed at NEB, for directly enriching the 5´ ends of primary transcripts. The method enables determination of transcription start sites at single base resolution (1). This is achieved by capping the 5´ triphosphorylated end of RNA with Vaccinia Capping System (NEB #M2080) and 3´-Desthiobiotin-GTP. The primary transcripts are then bound to Hydrophilic Streptavidin Magnetic Beads (NEB #S1421), washed and eluted with free biotin.