Abstract
Purpose: :
To determine the kind of mutations in the RS1 gene and characterize the clinical features of Japanese patients with X–linked juvenile retinoschisis (XLRS) associated with the mutations in the RS1 gene.
Methods: :
The coding sequence and the adjacent flanking intron sequences of all 6 exons of the RS1 gene were directly sequenced in 18 patients from 16 unrelated families with XLRS. The clinical findings evaluated at visual acuity, visual field area on the Goldmann perimeter, full–field electroretinogram amplitudes (ERG), optical coherence tomography (OCT) and fluorescein angiography (FA).
Results: :
10 different mutations in the RS1 gene, designated as Glu72Lys, Ala101Val, Arg102Trp, Arg141His, Pro192Leu, Arg200Cys, Arg209His, Arg213Trp, 186insT and 499insT mutations were identified in 16 unrelated families with XLRS. The Arg102Trp mutation was detected in 5 unrelated families with XLRS, and the Glu72Lys mutation was observed in 3 unrelated families with XLRS. The Ala101Val, Pro192Leu, 186insT and 499insT mutations are novel mutation in the RS1 gene. About 90 % patients exhibited negative b–wave in the standard flash ERG, although fundus examination and FA showed variable expressivity, such as macular schisis, golden yellow reflex, retinal detachment, large inner retinal break, neovascularization and vitreous hemorrhage.
Conclusions: :
Patients with XLRS associated with mutations in the RS1 gene showed clinical variability and variable severity, although the correlation between clinical features and genetic findings is currently unknown. Also our study suggested that the genetic analysis was very useful for accurate diagnoses of patients with XLRS.
Keywords: candidate gene analysis • mutations • retinal degenerations: hereditary