The detailed biochemical mechanism that leads to BBS is still unclear. The gene products encoded by these BBS genes, called BBS proteins, are located in the basal body and cilia of the cell. Using the round worm C. elegans as a model system, biologists found that BBS proteins are involved in a process called intraflagellar transport (IFT), a bi-directional transportation activity within the cilia along the long axis of the ciliary shaft that is essential for ciliogenesis and the maintenance of cilia. Recent biochemical analysis of human BBS proteins revealed that BBS proteins are assembled into a multiple protein complex, called "BBSome". BBSome is proposed to be responsible for transporting intracellular vesicles to the base of the cilia and to play an important role in the ciliary function. Since abnormalities of cilia are known to be related to a wide range of disease symptoms including those commonly seen in BBS patients, it is now widely accepted that mutated BBS genes affect normal cilia function, which, in turn, causes BBS. A theory that photoreceptor cells are nourished by the IFT of retinal cilia now offers a potential explanation for the retinal dystrophy common in BBS patients after their early years of life. Genes involved include: * BBsome: BBS1, BBS2, ARL6/BBS3, BBS4, BBS5, BBS7, TTC8/BBS8, BBS10, TRIM32/BBS11 BBS12, CCDC28B, CEP290, TMEM67, MKS1, MKKS * chaperone: BBS6
Bardet–Biedl syndrome
Prader–Willi syndrome
Schinzel–Giedion syndrome
Beckwith–Wiedemann syndrome
Langer–Giedion syndrome
Wiedemann–Steiner syndrome
Smith–Magenis syndrome
Wiedemann–Rautenstrauch syndrome