BBS2 and Bardet-Biedl syndrome: The loss of BBS genes has been reported to result in the ciliary dislocation of hedgehog signaling components, which may account for the embryonic developmental defects and polydactyly phenotypes in BBS (Eguether et al., 2014; Hey et al., 2021; Seo et al., 2011; Zhang et al., 2012a).