In this sense, BBS constitutes a clear example of the great importance of chaperone defects as determinant pathogenic factors, taking into account that up to 50% of families clinically diagnosed with BBS can harbor pathogenic variants in MKKS/BBS6, BBS10 and BBS12 genes (Billingsley et al., 2010; Muller et al., 2010; Deveault et al., 2011). This evidence concerns the gene MKKS and Bardet-Biedl syndrome.