Clinical and genetic features of retinoschisis in 120 families with <i>RS1</i> mutations.

Abstract

X-linked retinoschisis (XLRS), associated with <i>RS1</i>, is the most common type of X-linked retinopathy in children. This study aimed to identify clinical and genetic features of retinoschisis in 120 families with <i>RS1</i> variants in China. <i>RS1</i> variants were collected from our in-house exome data and were predicted by multiple-step bioinformatics analysis. Clinical data of 122 patients from 120 families with potential pathogenic <i>RS1</i> variants were analysed and summarised, respectively. Totally, 79 hemizygous variants (53 missense, 25 truncation and 1 indel), were detected. All except one (78/79, 98.7%), including 22 novels, were classified as potential pathogenic and detected exclusively in 120 families with retinoschisis. Clinical data demonstrated an average age of presentation at 5 years (1 month-41 years). Macular changes were classified as macular schisis (87.5%), macular atrophy (10.7%), normal (0.9%) and unclassified (0.9%). Patients with macular atrophy had older age but similar visual acuity compared with macular schisis. Peripheral retinal changes included flat retinoschisis (52.4%), bullous retinoschisis (BRS) (10.7%) and normal-like (36.9%) patients. Spontaneous regression was observed in two patients with BRS on follow-up examination. Visual acuity in the peripheral retinoschisis group was worse than that without peripheral retinoschisis. Almost all rare <i>RS1</i> variants were potential pathogenic. All patients with <i>RS1</i> pathogenic variants showed detectable characteristics in the macula and/or peripheral retina. Our data on <i>RS1</i> variants and associated clinical phenotypes may be of value for clinical diagnosis and genetic test of retinoschisis.