Chapter 8 - Bardet-Biedl syndrome

Abstract

Rod-cone dystrophy with early macular involvement, seen in 90% of Bardet-Biedl syndrome (BBS) patients, is a retinitis pigmentosa diagnosis relatively unique to BBS. With 21 causative genes discovered to date, BBS is an autosomal recessive, genetically heterogeneous, pleiotropic ciliopathy. Retinal degeneration is one cardinal feature of BBS. Others include cognitive impairment, renal anomalies, obesity, polydactyly, and hypogonadism. This chapter discusses the mode of inheritance and genes, proteins, and protein complexes that are involved in BBS, along with the BBS model organisms, molecular mechanisms, and transcriptional studies used to look at retinal degeneration. It also describes the relationships between BBS genes and other ciliopathy disorders such as Leber congenital amaurosis, Joubert syndrome, Senior-Løken syndrome, and nonsyndromic retinitis pigmentosa. Last, this chapter takes a look at advances in biotechnology and how these advances allow for a better understanding of the role of the BBS genes in retinal formation and function.