Transcriptional control is the process by which gene expression is regulated at the level of transcription, the first step in the process of gene expression. This regulation can involve a variety of mechanisms, including the binding of transcription factors to specific DNA sequences, the modification of chromatin structure, and the recruitment of RNA polymerase to the gene promoter. Transcriptional control plays a crucial role in determining when and to what extent a gene is expressed, and disruptions in this regulation have been linked to a variety of diseases and disorders. Researchers in this area study the mechanisms of transcriptional control and how they can be manipulated to modulate gene expression for therapeutic purposes.