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Ciliopathy: Bardet-Biedl Syndrome

  • Stephen H. Tsang
  • Alicia R. P. Aycinena
  • Tarun Sharma
Chapter
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 1085)

Abstract

  • Bardet-Biedl syndrome (BBS) is an autosomal recessive disease with a prevalence of about 1/125,000.

  • The syndrome involves mixed rod-cone dystrophy (which becomes obvious by 6 years of age). About two thirds of patients have postaxial polydactyly, and sometimes syndactyly, brachydactyly, and/or clinodactyly may be present. Hypogonadism and renal involvement occur in about 40%, mental retardation in about 50%, and truncal obesity in about 70%; it is present early, along with insulin resistance, type 2 diabetes, dyslipidemia, and hypertension. Vision becomes markedly impaired by about age 30 years. The BBS is genetically heterogeneous entity with considerable phenotypic variability.

  • Other associated problems include CNS-related ataxia, abnormal gait, and facial hypotonia, as well as anomalies such as high palate, hearing loss, and cardiac malformations. In males, there is oligospermia, leading to infertility.

  • Around 50–80% of BBS patients have renal malformations (like cyst, agenesis or scarring) and renal dysfunction leading to end-stage renal disease.

  • There are no pigmentary changes before the age of 1–2 years. Later, subtle pigmentary changes appear in the macula or peripapillary area. Several years later, pigments appear in the equatorial region, along with attenuation of retinal blood vessels and waxy pallor of the optic disc. Eventually, the macula may show atrophic changes (Figs. 33.1, 33.2 and 33.3).

  • Electroretinography (ERG) shows involvement of rods and cones and is abnormal even before the fundus shows changes.

  • A perimacular hyperfluorescent ring can be seen.

Keywords

Ciliopathy Bardet-Biedl syndrome 

Suggested Reading

  1. Ali MU, Rahman MSU, Cao J, Yuan PX. Genetic characterization and disease mechanism of retinitis pigmentosa; current scenario. 3 Biotech. 2017;7:251.  https://doi.org/10.1007/s13205-017-0878-3.CrossRefPubMedPubMedCentralGoogle Scholar
  2. Weihbrecht K, Goar WA, Pak T, Garrison JE, DeLuca AP, Stone EM, et al. Keeping an eye on Bardet-Biedl syndrome: a comprehensive review of the role of Bardet-Biedl syndrome genes in the eye. Med Res Arch. 2017;5  https://doi.org/10.18103/mra.v5i9.1526.

Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Jonas Children’s Vision Care, Bernard & Shirlee Brown Glaucoma Laboratory, Columbia Stem Cell Initiative-Departments of Ophthalmology, Biomedical Engineering, Pathology & Cell Biology, Institute of Human Nutrition, Vagelos College of Physicians and Surgeons, Columbia UniversityNew YorkUSA
  2. 2.Department of Ophthalmology, Columbia UniversityEdward S. Harkness Eye Institute, NewYork-Presbyterian HospitalNew YorkUSA
  3. 3.Department of Pediatrics, Division of GeneticsUniversity of California San FranciscoSan FranciscoUSA

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