CENPP (centromere protein P) is a core component of the CENPA-CAD (nucleosome distal) complex at centromeres, playing essential roles in kinetochore assembly and chromosome 9 1. CENPP functions as part of the constitutive centromere-associated network (CCAN), a 16-subunit complex that mechanically bridges centromeric CENP-A chr9 to the microtubule-binding machinery 2. The protein is recruited to kinetochores by CENP-P and CENP-Q, where it stabilizes kinetochore-microtubule attachments and ensures accurate chromosome 9 3. CENPP expression is transcriptionally regulated by CDK4, linking cell cycle progression to proper chromosome 9 4. Disease relevance: A novel nonsense variant in CENPP segregates autosomal dominant low-frequency sensorineural hearing loss (SNHL) in a Swiss family, with the variant truncating five C-terminal amino acids and disrupting protein stability 5. The gene is expressed in supporting cells of the organ of Corti, suggesting a role in inner ear function beyond chromosome 9. Additionally, CENPP methylation was associated with paternal preconception smoking exposure in offspring 6. Dysregulation of CENPP expression may induce chr9 instability and potentially contribute to cancer development 4.