Objective: To analyze the clinical symptoms and hereditary information of suspicious juvenile neuronal ceroid-lipofuscinosis (JNCL) and determine the genotype in order to explore the diagnosis clues in the patients with ophthalmologic manifestations being initial symptom. Methods: A case-control study was performed in this study.Two families were included in Eye Hospital of Wenzhou Medical in 2013 and 2017, respectively.Medical histories were collected and all participants underwent comprehensive ophthalmologic examinations, and the best corrected visual acuity (BCVA) was obtained.Fundus photography and optical coherence tomography (OCT) were used to image the retinal signs, and visual electrophysiology was recorded to evaluate the visual function.Genomic DNA of 3 patients who initially visited to ophthalmologists and 5 unaffected family members were extracted.Whole exome sequencing (WES), targeted exome sequencing (TES), Sanger sequencing and comprehensive analyses of pathogenicity were performed to determine the genetic cause of the patients.This study was approved by Ethics Committee of Eye Hospital of Wenzhou Medical University (KYK-2017-7), and written informed consent was obtained from each subject prior to any medical examination. Results: All patients presented bull eye sign and disorder of pigment on the fundus photograph, and the retinas were thinning on the OCT image, indicating the diffuse retinal pigment epithelium atrophy of macula and loss of outer layer structure of retina.Three mutations in CLN3 gene were identified by WES, TES, Sanger validation and assessments of pathogenicity, including c. 154T>C(p.Y52H), c.982G>C(p.A328P) and c. 906+ 5G>A, among which p. A328P was a novel mutation.Patients of F1 family harbored the compound heterozygous mutations c. 154T>C (p.Y52H) and c. 982G>C(p.A328P), while proband of F2 family harbored the homozygous splice site mutation c. 906+ 5G>A, which was reported to be a pathogenic mutation of JNCL.Co-segregation and comprehensive pathogenicity analysis revealed that the compound heterozygous mutations in F1 family and the homozygous mutation in a splice site in F2 family were the genetic causes of their phenotypes. Conclusions A novel mutation in CLN3 gene for JNCL is identified, which expands the mutation spectrum of CLN3 gene.Considering the high clinical heterogeneity of inherited retinal diseases, especially syndromic cases, genetic test through next generation plays a vital role in diagnosis, guiding future treatment and prognostic evaluation.

Objective:To explore the clinical characteristics and genetic etiology of a Chinese Hui family with nanophthalmos.Methods:A pedigree investigation was performed.The clinical features and genetic etiology analysis were conducted in this Chinese family with nanophthalmos who first visited Beijing Tongren Eye Center in October 2005 and were followed up until October 2023.This family included 25 individuals of 4 generations, among which there were 3 patients.All the patients underwent medical history collection and comprehensive ophthalmological examinations, including visual acuity, intraocular pressure, slit-lamp microscope, IOLMaster, ultrasound biomicroscopy, color fundus photography, B-scan ultrasonography, visual field, etc.Genomic DNA was extracted from the 3 patients and 3 phenotypically normal individuals.Disease-causing genes were screened by whole-exome sequencing.Bioinformatic analysis and prediction of pathogenicity of candidate variants were conducted, followed by further validation by Sanger sequencing and co-segregation analysis.All the included subjects were informed of the purpose and methods of the study and signed an informed consent form.The study protocol was reviewed and approved by the Ethics Committee of Beijing Tongren Hospital, Capital Medical University (No.TRECKY2021-241).Results:Nanophthalmos in this family was inherited in an autosomal recessive manner.The proband and his two sisters were diagnosed with nanophthalmos based on clinical evaluation of typical phenotypes including the reduction of visual acuity, hyperpresbyopia, short ocular axis, shallow anterior chamber, narrow anterior chamber angle, high intraocular pressure, crowded optic disc, tortuous retinal vessel, etc.companied by angle-closure glaucoma, exudative retinal detachment and uveal effusion and other common complications.Compound heterozygous variants c. 1010_1021del (p.His337_Glu340del) and c. 1486G>A (p.Glu496Lys) were detected in MFRP gene in all three patients, and c. 1010_1021del, one of the biallelic variants was first reported.Both variants were rare in healthy populations and were co-segregated within this pedigree.According to the standards and guidelines for the interpretation of sequence variants: a joint consensus recommendation of the American College of Medical Genetics and Genomics and the Association for Molecular Pathology, the variants were predicted to have strong pathogenicity and were the genetic cause of the nanophthalmos in this pedigree. Conclusions:This study finds a novel pathogenic variant c.1010_1021del in a nanophthalmos pedigree.