Definition: A bigwig is a type of RNA molecule that plays a crucial role in gene regulation. It has been identified as an important component of the chromatin structure, and it's known to be involved in various processes such as DNA methylation, transcriptional regulation, and stability of chromatin. Bigwigs are often found near transcription start sites (TSSs) and can be used to identify specific regions of the genome that are subject to gene expression changes or regulatory events.