Summary

The Bardet–Biedl syndrome (BBS) is a human genetic disorder with an array of clinical features affecting many body systems. BBS is a pleiotropic disorder with mostly monogenic causes. It is also considered a primary ciliopathy syndrome. It is characterised by obesity, pigmentary retinopathy, polydactyly, mental deficiency and hypogonadism and recently a sixth feature, renal disease, has also been described. Since none of the diverse symptoms of BBS by itself is diagnostic of the disorder and many of the symptoms only become apparent over time, diagnosis of the BBS is often delayed until about 9 years of age when visual problems first appear.