BBS12 is a vertebrate-specific chaperonin-like protein that functions as a component of the TRiC/CCT chaperone complex mediating BBSome assembly 1. As part of this complex, BBS12 interacts with BBSome subunits and CCT chaperonins to facilitate proper protein folding and promote vesicle trafficking to primary cilia during ciliogenesis 1. BBS12 also participates in adipogenic differentiation regulation. Biallelic mutations in BBS12 cause Bardet-Biedl syndrome (BBS), a rare autosomal recessive ciliopathy accounting for approximately 5% of BBS cases 2. Disease-causing mutations, including truncations and frameshifts, impair BBS12 protein stability and disrupt critical protein-protein interactions with other chaperonin-like BBS proteins (BBS6, BBS10) and BBSome core subunits 3. These functional defects compromise BBSome assembly and ciliary length, leading to characteristic BBS features: progressive rod-cone retinal dystrophy, truncal obesity, polydactyly, cognitive impairment, and kidney dysfunction 4. Renal abnormalities represent the most life-threatening complication, potentially progressing to end-stage renal failure 5. BBS12, along with BBS6 and BBS10, defines a vertebrate-specific chaperonin branch accounting for approximately one-third of total BBS mutational burden 2.