Usher syndrome (USH) is the most common cause of deaf-blindness diseases characterized by sensorineural hearing loss and retinitis pigmentosa. Patients are clinically and genetically heterogeneous, however, there are no convincing methods for prevention and treatment. USH2A is the most common disease-causing gene among 14 genes related to Usher syndrome. Great progress has been achieved in the pathogenic mechanism, animal models studies, diagnosis, and treatments based on gene therapy, cells transplantation and antisense oligonucleotide-based splice correction. Mutations in USH2A result in defects in USH complex proteins which involved in the transport function of the peripheral cilia region. There is respective limitations in established mouse and zebrafish animal models. Two promising treatments of this disease are introduced. One is clinical transplantation of visual organs which induced from corrected patient-derived induced pluripotent stem cells by the CRISPR/Cas9 system and another one is the RNA splicing therapy based on antisense oligonucleotides.
ObjectiveTo study the characteristics of the genotype and phenotypic in a family with X-linked retinoschisis (XLRS) due to RS1 mutation. MethodsA retrospective clinical study. An XLRS family of 4 generations of 26 people were included in the study. Among them, 8 participants were males and 7 participants were females. Routine ophthalmologic examination was performed on 3 patients in the family including the proband and 12 patients with normal phenotype. Optical coherence tomography was performed in 2 of the 3 patients. Peripheral venous blood was extracted from all participants, whole-genome DNA was extracted, and potential pathogenic genes were screened by Panel sequencing. Conservative analysis, pathogenicity analysis and protein structure prediction were carried out by software tools. The pathogenicity of gene mutations was analyzed according to the American Society of Medical Genetics and Genomics (ACMG) guidelines. ResultsThe proband was 3 years old. Optical coherence tomography (OCT) examination showed that the retinal core layer in the macular area of both eyes had a cystic change, which was segmented by vertical or oblique bridging tissue. The proband's uncle was 32 years old. OCT examination showed atrophy in the macular area of the left eye. The macular area of the right eye was cystoid, segmented by vertical or oblique bridging tissue. No abnormality was found in the fundus examination of the proband's parents and 10 members of his family. Panel sequencing showed that c.361C>T/ p.Q121X hemizygous mutation was found in the fifth exon of RS1 gene in the proband (Ⅳ3) and 2 patients (Ⅱ1, Ⅲ8). The mother was a heterozygous mutation carrier of the gene, while the father had no mutation. The mutant gene causes premature termination of RS1, a truncated protein encoding 224 amino acids to 120 amino acids. Of the 10 patients with normal fundus examination, 6 participants were normal. The mutation was carried by four people, which were women. Homology analysis of the protein sequence showed that the mutant site was highly conserved in 12 mammals. Three-dimensional structural analysis of RS1 protein showed that the c-terminal amino acid sequence of the mutant protein was more than 50% missing. Analysis of ACMG guidelines indicated that the mutation was pathogenic. ConclusionThe RS1 mutation site c.361C>T/p.Q121X is a new mutation site of XLRS.
Objective To find the new mutations of Leber's hereditary optic neuropathy (LHON). Methods Two LHON families were enrolled in this study. The probands and all maternal members in this two families were underwent ophthalmologic examinations. The ages of probands were seven and 14 years old respectively. A total of 358 healthy adults were enrolled in this study as control group. The genomic DNA from whole blood of participants were extracted. The entire mitochondrial genome of probands were PCR amplified and sequenced in 24 overlapping fragments using primers as designed. At the same time, the mtDNA of maternal relatives and 358 controls were also detected. Fourteen primate species were selected from GenBank to analyzed the phylogenetics of mitochondrial sequence. Results There was no ND4 G11778A, ND1 G3460A, ND6 T14484C mutational site in all maternal members. Molecular analysis of mtDNA in this two families identified the homoplasmic tRNAGluA14683G mutation and distinct set of variants belonging to the Asian haplogroup F1a1 and G2. The site was at theTpsi;C stem oftRNAGlu and extremely conserved among 14 primate species. It was anticipated that the A14683G increased the highly conserved C-G basepairing. Furthermore, the A14683G was absence in control group. Conclusion The tRNAGluA14683G mutation is likely a new mutation associated with LHON.
ObjectiveTo observe and analyze the genotype and clinical phenotype in 34 families of familial exudative vitreoretinopathy associated with (FEVR) gene variation.MethodsCohort study. Thirty-four FEVR families, in which the patients and both of their parents were all found to have FEVR-related gene mutations (proband 34 cases, 67 eyes; parents 68 cases, 136 eyes), were included in the study. These patients were identifIed from 722 FEVR patients through genetic screening, which diagnosed in Department of Ophtalmology of Xinhua Hospital and Tianjin Medical University Eye Hospital from January 2010 to December 2018. The probands and their parents underwent a comprehensive ophthalmological examination appropriate to their age, including BCVA, intraocular pressure, axial length, slit lamp examination, indirect ophthalmoscopy, FFA or color fundus photography or wide field color fundus photography. According to the severity of the disease, the clinical manifestations were divided into severe phenotype and mild phenotype. Thirty-four normal healthy people over 40 years old were included as the control group. The peripheral blood samples of FEVR family members and control group members were collected, and the genes known to be involved in FEVR, such as FZD4, LRP5, NDP, TSPAN12, ZNF408 and KIF11, were analyzed by next generation sequencing molecular genetics. The data were statistically analyzed by SPSS. The counting data was expressed in numbers or rates, and tested by Kruskal-Wallis test and χ2 test to find out the existence of significant difference.ResultsIn 67 eyes of the 34 probands, 48 eyes (71.64%) were classified into severe phenotype and 19 eyes (28.36%) were mild phenotype. In 136 eyes of 68 parents of the proband patients, 76 eyes (55.88%) were normal, 60 eyes (44.12%) were classified into mild phenotype, and no severe phenotype was found. A total of 65 variants of FEVR-related genes were detected in the 34 probands, of which LRP5 mutation was the most common (64.61%), followed by FZD4 (12.31%), NDP (10.77%), TSPAN12 (6.15%), ZNF408 (4.62%) and KIF11 (1.54%). Missense mutations were the most common variant in FEVR-related genes. However, the results of correlation analysis indicated that there was no significant correlation between the type of mutation and the severity of clinical phenotype (H=1.775, P=0.620). Among the 65 mutation types, 21 types have been previously identified and 44 were novel in this study. Thirty-nine eyes of 20 cases had only one single pathogenic mutation gene but with multiple mutation sites, 26 eyes of 13 cases carried 2 relevant pathogenic mutation genes, and 2 eyes in one case had 3 pathogenic mutation genes. The mutation frequencies of LRP5, NDP, ZNF408, FZD4, TSPAN12 and KIF11 genes in probands were significantly higher than those in control group, and the difference was statistically significant. The total mutation frequencies of LRP5, NDP, ZNF408, FZD4, TSPAN12 and KIF11 genes in proband group were significantly higher than those in control group (χ2=64.702, P＜0.001).ConclusionsIn the FEVR families, the most frequent mutations were those in LRP5, followed by FZD4, NDP, TSPAN12,ZNF408 and KIF11. Missense mutation is the most common type of FEVR-related gene mutation, but there is no significant correlation between the clinical phenotype and gene variation type. Most of the probands were with severe clinical phenotype, while most of the parents with FEVR pathogenic gene mutation showed normal or mild manifestations.
Objective To screen and analyze NR2E3 gene mutations in rentinitis pigmentosa (RP) patients from Ningxia area of China. Method 120 RP patients were enrolled in this study. The patients include 33 autosomal dominant RP (ADRP) patients from 18 families, 20 autosomal recessive RP (ARRP) patients from 15 families, and 67 simplex RP (SRP) patients.100 healthy people were collected as the control group. PCR and direct DNA sequencing were used to screen the entire coding region and splice sites of NR2E3 gene. Multiple analysis was used to study the effects of NR2E3 gene on RP. ResultsA total of 12 different sequence variants in the NR2E3 gene were identified, including 6 novel sequence variants. 5 variants were detected in non-coding regions; 7 variants were detected on the 4th, 6th, 7th exon which including 3 synonymous mutations and 4 missense mutations. All of them were NR2E3 gene polymorphisms and showed no positive correlation with the RP confirmed by the multivariate logistic regression analysis. The missense mutation of p.Glu121Lys was first found in 1 ADRP proband, 2 SRP patients and 2 control subjects. Among other 8 affected individuals in this ADRP family, 5 patients also had the p.Glu121Lys variant. Notably, the 6 affected individuals with p.Glu121Lys showed more serious ophthalmic findings (early onset and early central visual impairment) than other 3 affected individuals without p.Glu121Lys.Conclusion The mutation frequency of NR2E3 and p.Glu121Lys variant in NR2E3 gene in Ningxia RP patients were lower than previous reports in other populations.
Objective To screen mitochondrial DNA mutations in 3 Chinese pedigrees with Leberprime;s hereditary optic neuropathy (LHON) carrying the ND1 G3635A mutation. Methods 88 members（53 maternal relatives and 35 paternal relatives）in 3 pedigrees were enrolled. The ophthalmologic examinations were performed for all members, including visual acuity (standard logarithmic visual acuity charts), fundus photography (Canon fundus camera),visual field (Humphrey Visual Field Analyzer), color vision (Yu zhiping color vision plate), and visual evoked potentials (Roland Consult RETI port gamma, flash VEP). 16 members had LHON, 72 members did not have LHON. 135 healthy people from Wenzhou were included as the control group. Genomic DNA was extracted from peripheral blood leukocytes of all subjects. G3635A mutation was screened by PCR mplification of mitochondrial DNA for all subjects. Mitochondrial haplotypes and other mutations in the entire mitochondrial genome were also determined by PCR using 24 pairs of primers for the probands. Results Analysis of mitochondrial DNA (mtDNA) in 3 pedigrees revealed the presence of ND1 G3635A mutation in 3 probands and all maternal relatives, but not in paternal relatives and healthy controls. Probandprime;s haplogroup belong to East Asia group N9a3, D4, and R11a. In addition to the G3635A mutation, probands also had other variants including 12 variants in D-loop region, 6 variants in RNA gene, and 36 variants in protein-encoding gene. Conclusions G3635A mutation was identified in probands and maternal relatives of 3 pedigrees of LHON. It showed that G3635A mutation was the pathogenic molecular basis for those patients.
ObjectiveTo observe the clinical manifestation and gene mutation of a pedigree with Sorsby fundus dystrophy (SFD). Methods Ten members in 3 generations of a pedigree with SFD were included in this study. Four patients were observed in the pedigree, including 2 females and 2 males. All 10 members underwent comprehensive ophthalmic examinations, including best-corrected visual acuity, intraocular pressure, slit-lamp biomicroscopy, indirect ophthalmoscopy, fundus color photography and spectral domain optical coherence tomography. Genomic DNA was extracted from peripheral venous blood which was collected from all the members. Relevant exons of ocular diseases were detected by the next generation sequencing method from the proband. The other members underwent Sanger verification. Results Among the four patients, fading eyesight was appeared at their 44, 46, 47 and 40 year-old respectively. The two male patients had bilateral morbidity, and the two female patients had monocular symptoms. DNA sequencing results showed that the proband, other 3 patients and 2 members from the Ⅲ generation had heterozygous mutation of TIMP3 gene in exon 5. The amino acid encoded by TIMP3 gene No.204 codon changed from serine to cysteine (TIMP3:NM_000362:Exon5:c.A610T/p.S204C). CoclusionsThe invasion time of all the patients in this pedigree is after their 40 year-old. Heterozygous mutation at c.610A＞T (p.S204C) in TIMP3 gene is the causative gene of SFD in this pedigree.
Objective To investigate the correlation between mutation genotypes and phenotypes of X-linked retinoschisis (XLRS) patients. Methods 33 male XLRS patients, 26 female carriers and 100 normal subjects were enrolled in this study. All 33 XLRS patients were bilateral, which included 18 patients from 8 families and 15 sporadic patients. Among 66 XLRS eyes, there are microcystis-like foveal splitting in 49 eyes (74.2%), lamellar macular splitting in 43 eyes (65.2%), peripheral splitting in 32 eyes (48.5%), retinal detachment in 17 eyes (25.8%), and vitreous hemorrhage in 8 eyes (13.6%). Electroretinogram was performed on 42 eyes which showed decreased amplitude of b-wave. The 6 exons of RS1 gene were amplified by polymerase chain reaction and then directly sequenced.The correlation analysis was performed between mutation genotypes and phenotypes. Results There were 19 RS1 gene mutations including 6 novel mutations (p.Gly70Cys, p.Trp112Arg, p.Arg156Trp, p.His207ProfsX56, p.Arg209AlafsX28, p.Cys223Tyr). There was no correlation between mutation genotypes and phenotypes (chi;2=0.731, 3.438, 0.820, 3.208, 1.992; P＞0.05 ).Conclusions RS1 gene mutation is a major cause of XLRS. The RS1 mutation genotype is not correlated with phenotype, so that the prognosis cannot be predicted by the genotypes.
ObjectiveTo identify mutations in NDP, FZD4, LRP5, TSPAN12 in Chinese families with familial exudative vitreoretinopathy (FEVR) and observe the clinical features.MethodsRetrospective case series study. The 9 patients (18 eyes) and 5 normal members from 4 unrelated families were included in the study. The patients medical history and family history were collected in detail. All patients underwent best corrected visual acuity (BCVA), slit-lamp biomicroscopy, fundus colorized photography, fundus fluorescein angiography (FFA). Genomic DNA were collected from all the patients. Mutations were detected by directly sequencing to the whole coding region and exon-intron boundaries of NDP, FZD4, LRP5 and TSPAN12 gene. Polyphen and SIFT programs were used to predict the effects on the structure and functional properties of mutant protein.ResultsThere were two affected individuals in the family 2 carried LRP5 gene mutation [c.1330C＞T (p.R444C )] in exon 6 by sequence analysis. A score of 0.882 was acquired by Polyphen program analysis. And the missense change was predicted to be pathogenic by SIFT. Fundus changes of the proband showed angioplasia, tortuosity of peripheral vessels. And temporal dragging of the optic disc, peripheral avascular zone, neovascularization were found in FFA. Brush-like and straight of peripheral vessels were found in Ⅰ1. No variant was found in NDP, FZD4 and TSPAN12 gene.ConclusionOur study supports the gene mutation c.1330C＞T (p.R444C) of LRP5 is pathogenesis of FEVR. Patients with the same mutation could have variable phenotypic characteristics.
ObjectiveTo analyse epidermal growth factor receptor (EGFR) gene mutations in pathologically confirmed lung adenocarcinoma (LAC) samples obtained by endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). MethodsClinical data of 964 consecutive patients who underwent EBUS-TBNA in Department of Thoracic Surgery, Fudan University Shanghai Cancer Center from April 2009 to September 2013 were retrospectively reviewed. EGFR gene mutations in 77 LAC patients who were comfirmed by cell morphology and immunohistochemistry were analyzed. There were 48 males and 29 females with their median age of 61 (range 33-78) years, and 43 patients were smokers. ResultsAll the 77 LAC patients were confirmed by immunohistochemistry. Among them, 31 patients (40.26%) were found to have EGFR gene mutations. There was no statistical difference in EGFR gene mutations between male and female patients (P=0.088). Mutation rate of EGFR genes of non-smokers was significantly higher than that of smokers (P=0.032). ConclusionSamples obtained by EBUS-TBNA can be used for EGFR gene mutations analysis. The mutation rate of EGFR genes of non-smokers is higher than that of smokers.