title: Clinical presentations of X-linked retinoschisis in Taiwanese patients confirmed with genetic sequencing.
abstract: OBJECTIVE
  To investigate the clinical characteristics of X-linked retinoschisis (XLRS) and identify genetic mutations in Taiwanese patients with XLRS.
  
  
  METHODS
  This study included 23 affected males from 16 families with XLRS. Fundus photography, spectral domain optical coherent tomography (SD-OCT), fundus autofluorescence (FAF), and full-field electroretinograms (ERGs) were performed. The coding regions of the RS1 gene that encodes retinoschisin were sequenced.
  
  
  RESULTS
  The median age at diagnosis was 18 years (range 4-58 years). The best-corrected visual acuity ranged from no light perception to 20/25. The typical spoke-wheel pattern in the macula was present in 61% of the patients (14/23) while peripheral retinoschisis was present in 43% of the patients (10/23). Four eyes presented with vitreous hemorrhage, and two eyes presented with leukocoria that mimics Coats' disease. Macular schisis was identified with SD-OCT in 82% of the eyes (31/38) while foveal atrophy was present in 18% of the eyes (7/38). Concentric area of high intensity was the most common FAF abnormality observed. Seven out of 12 patients (58%) showed electronegative ERG findings. Sequencing of the RS1 gene identified nine mutations, six of which were novel. The mutations are all located in exons 4-6, including six missense mutations, two nonsense mutations, and one deletion-caused frameshift mutation.
  
  
  CONCLUSIONS
  XLRS is a clinically heterogeneous disease with profound phenotypic inter- and intrafamiliar variability. Genetic sequencing is valuable as it allows a definite diagnosis of XLRS to be made without the classical clinical features and ERG findings. This study showed the variety of clinical features of XLRS and reported novel mutations.
authors.affiliation: Department of Ophthalmology, Chang Gung Memorial Hospital, Linkou Medical Center, Taoyuan, Taiwan ; College of Medicine, Chang Gung University, Taoyuan, Taiwan.
authors.forename: Nan-Kai
authors.initials: NK
authors.lastname: Wang
authors.affiliation: Department of Ophthalmology, Chang Gung Memorial Hospital, Linkou Medical Center, Taoyuan, Taiwan ; College of Medicine, Chang Gung University, Taoyuan, Taiwan.
authors.forename: Laura
authors.initials: L
authors.lastname: Liu
authors.affiliation: Department of Ophthalmology, Chang Gung Memorial Hospital, Linkou Medical Center, Taoyuan, Taiwan ; College of Medicine, Chang Gung University, Taoyuan, Taiwan.
authors.forename: Ho-Min
authors.initials: HM
authors.lastname: Chen
authors.affiliation: Department of Ophthalmology, Mackay Memorial Hospital, Taipei, Taiwan ; Department of Optometry, Chung Shan Medical University, Taichung, Taiwan.
authors.forename: Shawn
authors.initials: S
authors.lastname: Tsai
authors.affiliation: Department of Ophthalmology, Mackay Memorial Hospital, Hsinchu, Taiwan.
authors.forename: Tsong-Chi
authors.initials: TC
authors.lastname: Chang
authors.affiliation: Department of Ophthalmology, National Taiwan University Hospital, Taipei, Taiwan ; Department of Ophthalmology, National Taiwan University Hospital; College of Medicine, National Taiwan University, Taipei, Taiwan.
authors.forename: Tzu-Hsun
authors.initials: TH
authors.lastname: Tsai
authors.affiliation: Department of Ophthalmology, National Taiwan University Hospital, Taipei, Taiwan ; Department of Ophthalmology, National Taiwan University Hospital; College of Medicine, National Taiwan University, Taipei, Taiwan.
authors.forename: Chung-May
authors.initials: CM
authors.lastname: Yang
authors.affiliation: Department of Ophthalmology, Chang Gung Memorial Hospital, Linkou Medical Center, Taoyuan, Taiwan ; College of Medicine, Chang Gung University, Taoyuan, Taiwan.
authors.forename: An-Ning
authors.initials: AN
authors.lastname: Chao
authors.affiliation: Department of Ophthalmology, Chang Gung Memorial Hospital, Linkou Medical Center, Taoyuan, Taiwan ; College of Medicine, Chang Gung University, Taoyuan, Taiwan.
authors.forename: Kuan-Jen
authors.initials: KJ
authors.lastname: Chen
authors.affiliation: Department of Ophthalmology, Chang Gung Memorial Hospital, Linkou Medical Center, Taoyuan, Taiwan ; College of Medicine, Chang Gung University, Taoyuan, Taiwan.
authors.forename: Ling-Yuh
authors.initials: LY
authors.lastname: Kao
authors.affiliation: College of Medicine, Chang Gung University, Taoyuan, Taiwan ; Department of Ophthalmology, Chang Gung Memorial Hospital, Keelung, Taiwan.
authors.forename: Ling
authors.initials: L
authors.lastname: Yeung
authors.affiliation: Department of Ophthalmology, Chang Gung Memorial Hospital, Linkou Medical Center, Taoyuan, Taiwan ; College of Medicine, Chang Gung University, Taoyuan, Taiwan.
authors.forename: Lung-Kun
authors.initials: LK
authors.lastname: Yeh
authors.affiliation: Department of Ophthalmology, Chang Gung Memorial Hospital, Linkou Medical Center, Taoyuan, Taiwan ; College of Medicine, Chang Gung University, Taoyuan, Taiwan.
authors.forename: Yih-Shiou
authors.initials: YS
authors.lastname: Hwang
authors.affiliation: Department of Ophthalmology, Chang Gung Memorial Hospital, Linkou Medical Center, Taoyuan, Taiwan ; College of Medicine, Chang Gung University, Taoyuan, Taiwan.
authors.forename: Wei-Chi
authors.initials: WC
authors.lastname: Wu
authors.affiliation: Department of Ophthalmology, Chang Gung Memorial Hospital, Linkou Medical Center, Taoyuan, Taiwan ; College of Medicine, Chang Gung University, Taoyuan, Taiwan.
authors.forename: Chi-Chun
authors.initials: CC
authors.lastname: Lai
mesh_terms: D000293:Adolescent; D000328:Adult; D000595:Amino Acid Sequence; D044466:Asian People / Q000235:genetics; D002648:Child; D002675:Child, Preschool; D017124:Conserved Sequence; D004252:DNA Mutational Analysis; D004596:Electroretinography; D005091:Exons / Q000235:genetics; D005136:Eye Proteins / Q000235:genetics*; D005260:Female; D050172:Genes, X-Linked; D056726:Genetic Association Studies; D040181:Genetic Diseases, X-Linked / Q000175:diagnosis* / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D009154:Mutation; D010375:Pedigree; D041441:Retinoschisis / Q000175:diagnosis* / Q000235:genetics*; D017386:Sequence Homology, Amino Acid; D013624:Taiwan; D055815:Young Adult
chemical_list: D005136:Eye Proteins; C108726:RS1 protein, human