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 analyze the new primary mutation in Chinese people with Leberprime;s hereditary optic neuropathy (LHON). Methods Genomic DNA was collected from 260 suspected LHON patients and 100 normal healthy persons. The mitochondria DNA mutation at nucleotide position (NP) 15257 and the hot spot (14452-14601 bp) of ND6 gene which include the mutations at NP (14482, 14498, 14568, 14596, 14495, and 14459) were screened by using polymerase chain reaction (PCR), heteroduplex-single strand conformation polymorphism (HA-SSCP) and restriction fragment length polymorphism (RFLP) analysis and sequencing. Primary mutation spectrum of Chinese race was analyzed. Results Eight kinds of polymorphism of mitochondria DNA were found in 260 suspected LHON patients and 100 normal healthy persons, including NP 14488C, 14518G, and 14617G which hadnrsquo;t been reported (http://www.mitomap.org/). No mutation at NP 15257, 14482, 14498, 14568, 14596, 14495, and 14459 was found. Conclusion The NP 15257A may not be the primary mutation in Chinese. Because of the race difference, 14452-14601 bp in ND6 gene may not be the hot spot in Chinese patients with LHON, and other hot spots may exist. (Chin J Ocul Fundus Dis, 2006, 22: 82-85)
Objective To investigate the disease-causing gene of Stargardt disease. Method Fifteen patients with Stargardt disease were analyzed with 11 primers of the 11 exons of ABCR gene by using PCR-SSCP and DNA direct sequencing techniques. Results Three newly detected disease-causing mutations were found. Among those mutations, one is a frameshift mutation and others are single base transition. Conclusion This research confirmed that ABCR gene is associated with Stargardt disease, and 3 new mutations of ABCR gene were found. (Chin J Ocul Fundus Dis,2000,16:240-243)
ObjectiveTo identify SCN9A gene mutation in a family with severe primary erythermalgia. MethodsClinical data of family were collected and the encoding exons and their flanking sequences of SCN9A gene were amplified and sequenced from genomic DNA samples. ResultsA heterozygous c.1185C→G was found in exon 9 of the proband, which resulted in N395K amino acid substitution. The mutation was not detected in the proband’s healthy mother or 50 unrelated healthy controls. ConclusionThe missense mutation of SCN9A gene is the underlying cause of the patient’s clinical phenotype.
Objective To observe and analyze the gene mutation and clinical phenotype of patients with cone and rod dystrophy (CORD). MethodsA pedigree investigarion. Two CORD pedigrees including 2 patients and 6 family members were enrolled in Ningxia Eye Hospital of People' Hospital of Ningxia Hui Automous Region for this study. The patients were from 2 unrelated families, all of whom were probands. Take medical history with best-corrected visual acuity (BCVA), color vision, slit lamp microscopy, indirect ophthalmoscopy, fundus color photography, optical coherence tomography (OCT), autofluorescence (AF), fluorescein fundus angiography (FFA), electroretinogram (ERG). The peripheral venous blood of patients and their parents was collected, whole genome DNA was extracted, Trio whole genome exome sequencing was performed, Sanger verification and pedigree co-segregation were performed for suspected pathogenic mutation sites. According to the law of inheritance, family history was analyzed to establish its genetic type. Mutational loci pathogenicity was analyzed according to the American College of Medical Genetics (ACMG) guidelines and 4 online tools. ResultsTwo CORD families showed autosomal recessive inheritance. The proband of pedigree 1 was female, 49 years old. Binocular vision loss with photophobia lasted for 9 years and night blindness for 4 years. The BCVA of right eye and left eye were 0.03 and 0.06, respectively. The results of ERG showed that the amplitudes of dark adaptation 0.01 b-wave and dark adaptation 3.0 a-wave and b-wave in both eyes were slightly decreased, and the amplitudes of light adaptation 3.0 a-wave and b-wave were severely decreased. The proband of pedigree 2 was male, 30 years old. Vision loss in both eyes for 4 years. Denying a history of night blindness. The BCVA of right eye and left eye were 0.3 and 0.2, respectively. The results of ERG showed that the amplitudes of dark adaptation 0.01 b-wave and dark adaptation 3.0 a-wave and b-wave in both eyes were slightly decreased, and the amplitudes of light adaptation 3.0 a-wave and b-wave were severely decreased. The color of optic disc in both eyes was light red, the macular area was atrophic, the foveal reflection disappeared, and the peripheral retina was punctate pigmentation. The main fundus changes in 2 patients were macular atrophy. The proband of pedigree 1 carried compound heterozygous variations c.439-2A>G (M1) and c.676delT (p.F226fs) (M2) on CDHR1 gene. Her father and mother carried M2 and M1 heterozygous mutations, respectively. The proband of pedigree 2 carried compound heterozygous variations c.2665dupC (p.L889fs) (M3) and c.878T>C (p.L293P) (M4) on C2orf71 gene. His father and mother carried M4 and M3 heterozygous mutations, respectively. According to ACMG guidelines and on line tools, 4 variations were considered as pathogenic level. ConclusionsM1 and M2 of CDHR1 gene and M3 and M4 of C2orf71 gene are new pathogenic mutations of CORD. All patients presented with the clinical phenotype of decreased visual acuity and macular atrophy.
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.
ObjectiveTo reveal the pathogenic mutation in a three-generation Chinese family with autosomal dominant familial exudative vitreoretinopathy (FEVR). MethodsThree patients and a healthy spouse from the index family with FEVR were recruited. The proband was a 5 years old boy. His mother and grandpa were presented with typical FEVR presentations, while his father with normal ocular fundus. DNA was extracted from peripheral blood samples taken from all four participants. All coding and exon-intron boundary regions of five targeted genes, including NDP, FZD4, LRP5, TSPAN12 and ZNF408 were amplified with polymerase chain reaction and sequenced using direct sequencing. In silico analyses were applied to determine the conservation of the mutation site, pathogenic effect and the potential protein crystal structural changes caused by the mutation. ResultsFZD4 c.478G > A, a susceptible mutation was found after four high frequency mutation sites which MAF values were higher than 0.001 was filtered among 5 single nucleotide variations detected in four participants, leading to the residue 160 changing from glutamate to lysine (p.E160K). Co-segregation analysis between genotypes and phenotypes revealed FZD4 p.E160K as the disease-causing mutation for this family. Conservational analysis suggested that this mutation site was highly conserved among all tested species. Functional analysis predicated that this mutation may be a damaging mutation. Crystal structural analysis also indicated that this mutation could lead to the elimination of the hydrogen bond between residue 160 and asparagine at residue 152, thus altering the tertiary structure of the protein and further impairing the protein function. ConclusionOur study demonstrates FZD4 p.E160K as a novel pathogenic mutation for FEVR.
ObjectiveThe clinical phenotypes and pathogenicity of isolated cone-rod dystrophy (CORD) caused by two novel complex heterozygous variants of the CEP290 gene were analyzed using high-resolution multi-mode imaging and gene detection techniques. MethodsA retrospective study. Two patients and two family members from a CORD family who were diagnosed by genetic testing at Henan Provincial People's Hospital in December 2021 were included in the study. All subjects underwent best-corrected visual acuity (BCVA), color fundus photography, autofluorescence, swept-source optical coherence tomography (SS-OCT), adaptive optics fundus imaging, static threshold field, full field and multiple electroretinogram (ERG) examination, as well as other systemic examinations throughout the body. The peripheral venous blood of the subjects was collected, and the whole genome DNA was extracted. DNA sequencing was performed using the Inherited Retinal Disease Kit PS400, and Sanger verification and pedigree co-segregation analysis were performed on the suspected pathogenic mutation sites. Validation was performed by Sanger sequencing, pathogenicity analysis was performed in accordance with the American College of Medical Genetics and Genomics (ACMG) guidelines. Conservation of variation among different species was analyzed by GERP++, Clustal Omega and Weblogo. ResultsBoth patients were male, and their ages were 21 and 29 years old, respectively. The right eye and left eye about BCVAs were 0.7, 0.4 and 0.3, 0.4, respectively. The full field and multiple electroretinogram ERG showed a decreased function of cones and rods, especially cones. SS-OCT showed thinning of the outer nuclear layer of macular, and attenuation of ellipsoid zone reflectivity in B-scan. Adaptive optics fundus imaging examination showed that the arrangement of cone cells in the fovea of the fovea was disordered and the density decreased, and the retinal pigment epithelial cells were seen through the atrophy of cone cells in some areas at 10°visual angle. No obvious abnormality was found in other systemic examinations of the whole body. Genetic testing showed that 2 novel compound heterozygous variants c.950T >A (p.Leu317*) (M1) and c.4144_4149del (p.Tyr1382_Glu1383del) (M2) in CEP290 were found in two patients. The first variant was predicted to be harmful in MutationTaster and CADD. GERP++ showed highly conserved among different species. The pathogenicity of the variant was suspected to be likely pathogenic according to ACMG guidelines. The pathogenicity of the second variant was uncertain significance. The parents of the proband had no similar ocular abnormalities. Verified by Sanger sequencing, it was consistent with co-separation in the family. ConclusionsPatients with pure CORD caused by CEP290 gene mutation still retain better vision when the cone structure is abnormal, the density is decreased, and the function of cone and rod cells is decreased. CEP290 M1 and M2 are newly discovered nonsense mutations and newly discovered deletion mutations, which expanded the causative gene spectrum of pure CORD.
Objective To detect and analyse the mutations in rhodopsin gene of members in a family affected by autosomal dominant retinitis pigmentosa (ADRP). Methods Using the polymerase chain reaction (PCR), we amplified exon 1-5 of rhodopsin gene in patients with ADRP,and analyzed it with direct sequence measuement. Results The Gly-182-Asp mutation in the rhodopsin gene was detected in most of affected members of this ADRP family, but no mutation was detected in two affected members and the control ones. Conclusion We cannot regard the Gly-182-Asp mutation in the rhodopsin gene as the pathagenic factor of the ADRP family. It is likely there is a new gene next to the rhodopsin gene. (Chin J Ocul Fundus Dis, 2002, 18: 256-258)
ObjectiveTo analyze the clinical and genetic characteristics of ADGRV1 gene mutation epilepsy.MethodsA retrospective collection of 26 patients with epilepsy diagnosed and related gene sequencing was performed in the Affiliated Hospital of Jining Medical College from January 2018 to December 2018. Five epilepsy patients with ADGRV1 mutations were screened out, and their clinical characteristics and gene mutation characteristics were summarized.ResultsA total of 5 epilepsy patients with ADGRV1 mutation were collected, including 1 male and 4 females, with an average age of (7±5.83) years. Three patients had a family history of epilepsy, and the father of the other two patients had a history of febrile seizures. 2 cases showed generalized tonic-clonic seizures, and 3 cases showed partial seizures followed by generalized seizures. The results of genetic testing revealed 7 mutation sites in the ADGRV1 gene, of which one missense mutation site c.2039A>G has been reported in the literature. Two of the 5 patients underwent epilepsy surgery, and they were still treated with multiple anti-epileptic drugs for a long time after the operation, and the other 3 patients were treated with anti-epileptic drugs for a long time. At present, 4 out of 5 patients had seizures still not under effective control, and 1 case did not relapse after being followed up for nearly 1 year.ConclusionThe clinical features of epilepsy caused by ADGRV1 gene mutation are early onset, mainly manifested as general tonic-clonic seizures or partial seizures secondary to generalized seizures, accompanied by disturbance of consciousness during seizures. The combined treatment of anti-epileptic drugs and postoperative anti-epileptic drugs is less effective. Genetic testing can guide genetic counseling and assisted diagnosis.