Abstract
Purpose: :
To report a complex mutation consisting of deletion /insertion at the same nucleotide in exon 5 of RS1 gene in a large family affected with X-linked retinoschisis (XLRS), describe the clinical-electrophysiological features and establish the biochemical phenotype of the affected males.
Methods: :
Six affected males of a 7-generation family with 106 members were examined; their ophthalmological evaluation included OCT and ERG. Mutation screening of the RS1 gene was done by direct sequencing of their genomic DNA. RS1 minigenes were constructed for the Wt and exon 5 mutation by PCR of the genomic DNA, followed by molecular cloning. Expression of mutant RS1 protein was assessed by transfecting COS-7 cells with the minigene constructs.Results &
Conclusions: :
The 354del1ins18 mutation gives an RS1 null biochemical phenotype. The cross-sectional clinical study suggested a rapidly progressive XLRS phenotype in which the ERG changed markedly across 4 decades with severe macular atrophy by age 31-42 y/o.
Keywords: retinal degenerations: hereditary • pathology: human • retina: distal (photoreceptors, horizontal cells, bipolar cells)