Chromobox Homolog 1 (CBX1), also known as HP1-beta, is a highly conserved protein involved in chromatin organization and gene silencing. It is a key component of heterochromatin, binding to histone H3 trimethylated at lysine 9 (H3K9me3) and playing a critical role in maintaining epigenetic states. CBX1 contributes to the formation of repressive chromatin structures, influencing processes such as cell cycle regulation, DNA repair, and transcriptional repression. Dysregulation of CBX1 has been implicated in various diseases, including cancer.