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Ciliopathy: Usher Syndrome

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

Abstract

  • Ciliopathies are a group of disorders caused by a defect in ciliogenesis, ciliary protein trafficking. Because nearly every cell in the body (including the photoreceptors) contains cilia, defects in ciliary proteins typically affect multiple organ systems.

  • Usher syndrome is the most common syndromic cause of retinitis pigmentosa (RP) and accounts for 10–20% of cases of RP

  • Inheritance is autosomal recessive, and the retinal dystrophy is usually rod-cone dystrophy (Figs. 32.1 and 32.2).

  • These patients have RP with sensorineural hearing loss (partial or complete) since birth; some may have vestibular dysfunction.

  • Most patients retain central vision of about 20/40 until about age 40.

  • Usher Syndrome 1 (USH1): Profound congenital sensorineural hearing loss on audiometry, absent vestibular function, and typical RP (onset by 10 years of age); accounts for about 70% of all Usher cases. Patient may benefit from a cochlear implant. The retinitis pigmentosa occurs at an early age (childhood onset) and progress slowly.

  • Usher Syndrome 2 (USH2): Moderate to severe congenital sensorineural hearing loss on audiometry (predominantly for higher frequencies), normal vestibular function, and typical RP (onset by 20 years of age); accounts for about 26% of all Usher cases.

  • Usher Syndrome 3 (USH3): Progressive sensorineural hearing loss and typical RP (onset in second decade); accounts for about 4% of all Usher cases. Vestibular function is normal in about half of patients, but abnormal in the other half.

Keywords

Usher syndrome Ciliopathy Retinitis pigmentosa 

Suggested Reading

  1. Lentz J, Keats BJB. Usher syndrome Type I. 1999 Dec 10 [updated 2016 May 19]. In: Adam MP, Ardinger HH, Pagon RA, Wallace SE, LJH B, Stephens K, Amemiya A, editors. GeneReviews® [Internet]. Seattle: University of Washington, Seattle; 1993–2018a. Available from http://www.ncbi.nlm.nih.gov/books/NBK1265/.
  2. Lentz J, Keats B. Usher syndrome Type II. 1999 Dec 10 [updated 2016 Jul 21]. In: Adam MP, Ardinger HH, Pagon RA, Wallace SE, LJH B, Stephens K, Amemiya A, editors. GeneReviews® [Internet]. Seattle: University of Washington, Seattle; 1993–2018b. Available from http://www.ncbi.nlm.nih.gov/books/NBK1341/.
  3. Lopes VS, Williams DS. Gene therapy for the retinal degeneration of usher syndrome caused by mutations in MYO7A. Cold Spring Harb Perspect Med. 2015;5:a017319.CrossRefGoogle Scholar

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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