Objective To review retinitis pigmentosa (RP)-related gene researches in China. Methods RP genes and RP gene therapy as key words were searched from those online databases including China Knowledge Resource Integrated Database of China National Knowledge Infrastructure (CNKI), National Center for Biotechnology Information (NCBI), Human Gene Mutation Database (HGMD), and Human Genome Variation Society (HGVS). Related papers written by authors from China or other countries, published from 1991 to 2011 were collected for analysis. Results Overall 60 RP related genes have been identified now. Chinese researchers from 29 hospitals and research institutes confirmed 17 RP-related gene changes (239 mutations, 131 of them are pathogenic) in 300 RP families and 1572 sporadic RP patients from 1991 to 2011, as reported in 66 papers. Mutations in rhodopsin (RHO) gene, NR2E3 gene and RP1 gene were found in 2.0%, 2.9% and 1.0% of Chinese RP patients respectively. The relationship between genotypes and clinical phenotypes were investigated in 15 papers, including RHO gene, RDS gene, RP1 and RPGR or RP3 gene in ADRP families. Gene therapy for RP has been investigated in 4 papers. Seven hundred and eighteen papers about RP genemutation screening have been published from other countries, and more than 2000 variants were identified which including 352 disease-causing mutations. Mutations of RHO gene, RDS and RP1 were found in 25%-50%, 8% and 5% -10% of ADRP patients in Caucasian populations. RPGR mutations were found in 70%-80% of XLRP patients in Caucasian populations, and 50% -60% of mutations are identified in open reading frame (ORF) 15. Totally 391 papers about gene therapy for RP have been published. Conclusions Seventeen RP-related genes have been studied and 131 pathogenic mutations were found in China. Considering Chinese population, our RP research is still behind other countries.
Objective To observe the hereditary types and clinical characteristics of 137 patients with retinitis pigmentosa (RP) in Ningxia. Methods One hundred and thirty-seven patients with RP who diagnosed by the examinations of visual acuity, optometry, direct or indirect ophthalmoscope, visual field, optical coherence tomography (OCT) and electroretinogram were enrolled. The hereditary types and clinical characteristics were analyzed according to the family history and the Results of ophthalmologic examinations. Results One hundred and thirty-seven patients included 29 autosomal dominant RP (ADRP) patients from 8 families (7.4%), 16 autosomal recessive RP (ARRP) patients from 15 families (13.9%), 10 X-linked RP (XLRP) from 3 families (2.8%), and 82 simplex RP (SRP) patients (75.9%). There were 15 consanguineous marriage families out of 26 families with RP history (57.7%). The patients were classified as typical RP (102 patients, 74.5%) and atypical RP (35 patients, 25.5%). All the ADRP and XLRP patients showed typical clinical features of RP. Ten (62.5%) of ARRP patients and 53 (64.6%) of SRP patients had typical features of RP. Six (37.5%) of ARRP patients and 29 (35.4%) of SRP patients had atypical features of RP. Among atypical RP patients, 17 (48.6%) patients were nonpigmented RP which including 3 patients were misdiagnosed as amblyopia during childhood. The logarithm of minimal angle of resolution (logMAR) best corrected visual acuity (BCVA) of ADRP patients was 1.04plusmn;0.51 at the age older than 51 years, while the BCVA of ARRP and XLRP patients were 0.92plusmn;0.61 and 1.70plusmn;0.02 respectively at 21 to 30 years of age. One hundred and twentythree (89.8%) patients suffered from varying degrees of myopia. OCT showed that the average thickness of macular fovea in ADRP patients was (185.73plusmn;1.23) mu;m at the age older than 51 years, while in ARRP and XLRP patients were (173.21plusmn;0.98) and (170.49plusmn;1.15) mu;m respectively at 21 to 30 years of age. Conclusions ADRP and XLRP are typical RP. All atypical RP are ARRP and SRP. Non-pigmented RP are mainly seen in atypical RP which often misdiagnosed as amblyopia during childhood. The photoreceptors in macula are damaged in the early stage and the decline of visual acuity occurred at 21 to 30 years of age in patients with ARRP and XLRP. The ADRP patients has late slower decline of visual acuity and retain some visual acuity at the age older than 51 years.
ObjectiveTo observe the disease-causing genes and the inheritance in sporadic retinitis pigmentosa (sRP) in Ningxia region. Methods49 sRP patients and 128 family members were recruited for this study. All the patients and family members received complete ophthalmic examinations including best corrected visual acuity, slit-lamp microscope, indirect ophthalmoscopy, fundus color photography, visual field, optic coherence tomography, full view electroretinogram. DNA was extracted from patients and family members. Using exon combined target region capture sequencing chip to screen the 230 candidate disease-causing gene mutations, polymerase chain reaction and direct sequencing were used to confirm the disease-causing mutations. Results24/49 patients (49.0%) had identified disease-causing genes, totally 16 genes were involved. There were 41 mutation sites were found, including 32 new mutations (78.0%). The disease-causing genes include USH2A, C2orf71, GNGA1, RPGR1, IFT140, TULP1, CLRN1, RPE65, ABCA4, GUCA1, EYS, CYP4V2, GPR98 and ATXN7. Based on pedigree analysis, 20 patients were autosomal recessive retinitis pigmentosa, 3 patients were autosomal dominant retinitis pigmentosa and 1 patient was X linked retinitis pigmentosa. 3/7 patients with USH2A mutations were identified as Usher syndrome. ConclusionsUSHZA is the main disease-causing of sRP patients in Ningxia region. 83.3% of sRP in this cohort are autosomal recessive retinitis pigmentosa.
ObjectiveTo evaluate the photoreceptor-protective effects of Cdk5 inhibitor Roscovitine on retinal degeneration in Royal College of Surgeons (RCS) rat. MethodsThe RCS rats were divided into three groups according to postnatal days: the early (17 days), medium (25 days) and late intervention group (35 days). Cdk5 inhibitor Roscovitine were used in the right eyes by intravitreal injection as experimental eyes and Roscovitine solvent dimethylsulfoxide were used in the left as control at postnatal 17, 25, 35 days. Hematoxylin-eosin (HE) staining was used to observe the thickness of outer nuclear layer. The expression of Cdk5 P25 and cleave-caspase 3 in the retina was evaluated by immunohistochemistry. The protein expression of cleave-caspase 3 in the retina was determined by Western blot. The apoptosis of retinal cells was examined by terminal-deoxynucleotidyl transferase mediated nick end labeling. ResultsHE staining showed that thickness of outer nuclear layer in the early and medium intervention groups were significantly thicker than that in the control group (P < 0.05), particularly in the early intervention group. And there was no significant change in the late intervention group (P > 0.05). The expression level of Cdk5, p25, cleave-caspase 3 in the outer nuclear layer in three intervention groups were lower than that in the control group (P < 0.05), especially in the early intervention group. ConclusionCdk5 inhibitor Roscovitine can delay the retinitis pigmentosa process in RCS rats by early, medium interventional therapy and may have a certain degree of photoreceptor-protective effects.
Objective To observe the gene mutation and clinical phenotype of patients with retinitis pigmentosa (RP) and cone rod dystrophy (CORD). Methods Thirty-seven patients with RP and 6 patients with CORD and 95 family members were enrolled in the study. The patient’s medical history and family history were collected. All the patients and family members received complete ophthalmic examinations to determine the phenotype, including best corrected visual acuity, slit lamp microscope, indirect ophthalmoscopy, color fundus photography, optical coherence tomography, full-field electroretinogram, and fluorescein fundus angiography. DNA was abstracted from patients and family members. Using target region capture sequencing combined with next-generation sequencing to screen the 232 candidate pathogenic mutations. Polymerase chain reaction and direct sequencing were used to confirm the pathogenic pathogenic mutations and Co-segregation is performed among members in the family to determine pathogenic mutation sites. The relationship between genotype and clinical phenotype of RP and CORD was analyzed. Results Of the 37 patients with RP, 13 were from 6 families, including 4 families with autosomal dominant inheritance, 2 families with autosomal recessive inheritance, and 3 in 6 families were detected pathogenic gene mutations. 24 cases were scattered RP. Six patients with CORD were from four families, all of which were autosomal recessive. Of the 43 patients, 21 patients were detected the pathogenic gene mutation, and the positive rate was 48.8%. Among them, 15 patients with RP were detected 10 pathogenic gene mutations including USH2A, RP1, MYO7A, C8orf37, RPGR, SNRNP200, CRX, PRPF31, C2orf71, IMPDH1, and the clinical phenotype included 10 typical RP, 2 cases of RPSP, 3 cases of Usher syndrome type 2 and 6 cases of CORD patients were all detected pathogenic gene mutations, including 2 cases of ABCA4, 2 mutations of RIMS1 gene, 1 case of CLN3 gene mutation, and 1 case of CRB1 and RPGR double gene mutation. Conclusions RP and CORD are clinically diverse in genotype and clinically phenotypically similar. For patients with early RP and CORD, clinical phenotype combined with genetic analysis is required to determine the diagnosis of RP and CORD.
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.
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.
ObjectiveTo identify 3 the disease-causing genes and mutations of Leber congenital amaurosis (LCA), and to study the correlation of phenotype and genotype. MethodsA retrospective study. Four LCA patients and seven family members who were diagnosed by eye examination in Ning Xia Eye Hospital of People's Hospital of Ningxia Hui Autonomous Region from January to December 2021 were included in the study. Four patients were from 3 unrelated families. Detailed collection of medical history and family history were received. Related ophthalmologic examination were collected and genomic DNA was extracted from peripheral blood. Whole-exome sequencing method was used for genetic diagnosis. The identified variant was confirmed with Sanger sequencing. Potential pathogenic mutation was analyzed using software and conserved domain analysis and performed co-separated analysis between the family member and the proband. ResultsOf the 4 patients, 1 patient was males and 3 patients were females; the age was from 4 to 18 years. Nystagmus were seen in 3 cases, finger pressing eyes and night blindness was seen in 1 cases; electroretinogram showed 4 cases of extinction or near extinction. The foveal reflection was visible in all eyes, and there was no obvious abnormality in the peripheral retina. One eye had strong reflection signal with raised ellipsoid in macular area; two eyes had weak reflection signal faintly visible between retinal layers; 1 eye had increased blood vessel branches, peripheral retinal non-perfusion area with capillary leakage; annular strong autofluorescence in macular area 4 eyes. No obvious abnormality was found in the phenotypes of family members. Genetic testing showed that the proband of pedigree 1 (Ⅱ-1) was found a homozygous missense mutation in c.640A>T (p.C214S) (M1) of PRPH2 gene. The proband of pedigree 2 (Ⅱ-2) was found compound heterozygous mutation in c.1256G>A(p.R419Q) (M2) and c.1A>C (p.M1L) (M3) of TULP1 gene. The proband 3 (Ⅱ-1) and her sister (Ⅱ-2) were both found compound heterozygous mutation in c.1943T>C (p.L648P) (M4) and c.380C>T (p.P127L) (M5) of GUCY2D gene. The parents and sister (Ⅱ-1) of the proband in family 2 and the parents of the proband in family 3 were all carriers of the corresponding heterozygous variant. M1, M3, M4, M5 were novel mutations and unreported. The genotype and disease phenotype were co-segregated within the family. According to the analysis of pedigree and genetic testing results, all 3 families were autosomal recessive inheritance. The amino acid conservation analysis found that M1, M2, M3, M4, and M5 were highly conserved among species. The results of bioinformatics analysis were all pathogenic variants. ConclusionsPRPH2 gene M1, TULP1 gene M3, and GUCY2D gene M4, M5 were novel mutations and not been reported in the literature and database. This research expanded the gene mutation spectrum of LCA. The patients with LCA have available characterristics, including onset age, varying ocular fundus and severe visual impairment.