title: Novel mutations of the RS1 gene in a cohort of Chinese families with X-linked retinoschisis.
abstract: OBJECTIVE
  X-linked retinoschisis is a retinal dystrophy caused by mutations in the RS1 gene in Xp22.1. These mutations lead to schisis (splitting) of the neural retina and subsequent reduction in visual acuity in affected men (OMIM # 312700). The aim of this study was to identify the RS1 gene mutations in a cohort of Chinese patients with X-linked retinoschisis, and to describe the associated phenotypes.
  
  
  METHODS
  Patients and unaffected individuals from 16 unrelated families underwent detailed ophthalmic examinations. After informed consent was obtained, genomic DNA was extracted from the venous blood of all participants. All exons including the exon-intron boundaries of the RS1 gene, were amplified by PCR and the products were analyzed by direct sequencing. Long-range PCR followed by DNA sequencing was used to define the breakpoints of the large deletion.
  
  
  RESULTS
  Sixteen male individuals from 16 families were diagnosed with retinoschisis by clinical examination. The median age at review was 13.2 years (range: 5-34 years); the median best-corrected visual acuity upon review was 0.26 (range 0.02-1.0). Foveal schisis was found in 82.8% of the eyes (24/29) while peripheral schisis was present in 27.5% of the eyes (8/29). Sequencing of the RS1 gene identified 16 mutations, nine of which were novel. The mutations included eight missense mutations, all located in exons 4-6 (50.0%), two nonsense mutations (12.5%), four small deletions or insertions (25.0%), one splice site mutation (6.25%), and one large genomic deletion that included exon1 (6.25%).
  
  
  CONCLUSIONS
  The mutations found in our study broaden the spectrum of RS1 mutations. The identification of the specific mutation in each pedigree will allow future determination of female carrier status for genetic counseling purposes.
authors: Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Lab. Beijing, China.
authors: Jieqiong
authors: J
authors: Chen
authors: Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Lab. Beijing, China.
authors: Ke
authors: K
authors: Xu
authors: Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Lab. Beijing, China.
authors: Xiaohui
authors: X
authors: Zhang
authors: Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Lab. Beijing, China.
authors: Zhe
authors: Z
authors: Pan
authors: Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Lab. Beijing, China.
authors: Bing
authors: B
authors: Dong
authors: Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Lab. Beijing, China.
authors: Yang
authors: Y
authors: Li
mesh_terms: D000293:Adolescent; D000328:Adult; D000595:Amino Acid Sequence; D044466:Asian People / Q000235:genetics*; D001483:Base Sequence; D002648:Child; D002675:Child, Preschool; D002681:China; D015331:Cohort Studies; D004252:DNA Mutational Analysis; D005136:Eye Proteins / Q000737:chemistry / Q000235:genetics*; D005190:Family; D005260:Female; D005654:Fundus Oculi; D005808:Genes, Recessive; D050172:Genes, X-Linked / Q000235:genetics*; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics*; D010375:Pedigree; D041441:Retinoschisis / Q000235:genetics*; D016415:Sequence Alignment; D041623:Tomography, Optical Coherence
chemical_list: D005136:Eye Proteins; C108726:RS1 protein, human