ObjectiveTo investigate the current status of research in gene therapy for retinitis pigmentosa (RP) from 2005 to 2024. MethodsThe literature related to gene therapy for RP included in the Web of Science Core Collection dataset from January 1, 2005 to September 15, 2024 was retrieved and screened. The bibliometrix package of R software was used to analyze the annual trend of the number of publications, citation frequency, distribution of countries/regions of the literature, and distribution of journals containing the articles. CiteSpace software was used to perform keyword clustering analysis and the keywords bursts analysis. ResultsA total of 209 articles were included. There was an overall fluctuating upward trend of annual publications from 2005 to 2024, with the highest number of publications in 2023 at 26 (12.4%, 26/209), and the lowest number of publications in 2006 at 2 (0.9%, 2/209). There was an overall increasing trend in the frequency of citations to relevant literature. Corresponding authors from the United States had the highest total number of publications with 98 (46.9%, 98/209). Among authors, Hauswirth from the University of Florida, USA, had the most with 25 (12.0%, 25/209). Among institutions, Columbia University, USA, had the most with 55 (26.3%, 55/209). Among journals, Mol Ther had the most with 25 (12.0%, 25/209), and it had the highest 2023 impact factor of 12.1. Keyword clustering analysis yielded eight valid clusters, namely #0 P23H, #1 AAV, #2 PDE6B, #3 CRB1, #4 RPGR, #5 antisense oligonucleotide, #6 NR2E3, and #7 NRL, which intersected with each other with good continuity. The keywords bursts analysis showed that the keyword with the longest emergence time was RNAi, followed by PDE and PDE6. USH2A, CRB1, CRISPR Cas9, base editing, and ORF15 were keywords that emerged in recent years and were continuously studied. ConclusionsRP gene therapy research literature has shown an increasing trend from 2005 to 2024, with the highest number of publications from research organizations and scholars in the United States. Currently, studies focus on RHO, PDE6B, CRB1, RPGR, NR2E3, and NRL gene. In recent years, there has been a gradual increase in studies on USH2A, CRB1 genes, and the RPGR ORF15 region. CRISPR Cas9 and base editing gene therapy strategies are being developed.
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 observe the clinical characteristics of primary retinitis pigmentosa (RP) complicated with glaucoma.MethodsA retrospective clinical study. From June 2008 to March 2020, the diagnosis of primary RP were included in the diagnosis confirmed by the eye examination of West China Hospital of Sichuan University included 4794 eyes of 2432 patients. Among them, 4679 eyes (97.2%, 2364/2432) were in 2364 cases with RP alone, and 115 eyes were in 68 cases with RP combined with glaucoma (2.80%, 68/2432). All affected eyes underwent best corrected visual acuity (BCVA) and intraocular pressure examination. The BCVA examination was carried out using the international standard visual acuity chart, which was converted into the logarithmic minimum angle of resolution (logMAR) visual acuity during statistics. The 67 eyes of 40 patients with RP and glaucoma with complete follow-up data were analyzed to observe the proportion of different glaucoma types, logMAR BCVA, intraocular pressure and other clinical characteristics, as well as treatment methods and post-treatment intraocular pressure control. After treatment, the intraocular pressure ≤21 mm Hg (1 mm Hg=0.133 kPa) was regarded as intraocular pressure (IOP) control; ＞21 mm Hg was regarded as uncontrolled IOP.ResultsAmong the 67 eyes of 40 cases with complete follow-up data, 5 cases (7 eyes) with primary open-angle glaucoma (10.45%, 7/67), 56 cases (58 eyes) with angle-closure glaucoma (ACG) (86.57%, 58/67), 4 cases (4 eyes) with neovascular glaucoma (5.97%, 4/67), 2 of them had both ACG and neovascular glaucoma. Among 58 ACG eyes, 17 eyes were acute ACG (25.37%, 17/67), 21 eyes were chronic ACG (31.34%, 21/67), and 2 eyes were suspicious angle closure (2.99%, 2/67), lens dislocation secondary to angle-closure glaucoma in 8 eyes (11.94%, 8/67), chronic angle-closure glaucoma after anti-glaucoma surgery, intraocular lens shift in 5 eyes (7.46%, 5/67), 5 eyes (7.46%, 5/67) secondary to glaucoma with true small eyeballs. The logMAR BCVA 3.50 of the affected eye,＜3.50-＞2.00, ≤2.00-≥1.30,＜1.30-＞1.00, ≤1.00-0.52,＜0.52 were 9 (13.43%, 9/67), 30 (44.78%, 30/ 67), 7 (10.45%, 7/67), 4 (5.97%, 4/67), 11 (16.42%, 11/67), 6 (8.96%, 6/67) eyes, which correspond to mean intraocular pressure were 32.31±11.67, 30.15±14.85, 28.17±13.19, 31.50±17.25, 18.71±8.85, 14.12±4.25 mm Hg. Among 67 eyes, 37eyes (55.22%, 37/67), 18eyes (26.86%, 18/67), and 6 (8.96%, 6/67) eyes underwent surgery, medication alone, and peripheral iris laser perforation treatment, respectively. The treatment of 6 eyes was abandoned (8.96%, 6/67). Malignant glaucoma occurred in 3 eyes (8.11%, 3/37) after the operation, all of which were after trabeculectomy of the ACG eye. After treatment, intraocular pressure was controlled in 37 eyes (55.22%, 37/67), 19 eyes were not controlled (28.36%, 19/67), and 11 eyes were lost to follow-up (16.42%, 11/67).ConclusionsThe incidence of glaucoma in patients with primary RP is 2.80%. ACG is more common, and the combined lens dislocation or intraocular lens shift is more common.
ObjectiveTo observe and analyze the pathogenic genes and clinical phenotype characteristics of retinitis pigmentosa sinepigmento(RPSP). MethodsA retrospective clinical study. Two patients (proband) and five family members from two RPSP families admitted to Xiamen Eye Center of Xiamen University in December 2022 and Shenzhen Eye Hospital in July 2023 were included in the study. Two families have no blood relationship and were both Han Chinese. Detailed ocular and systemic medical history and specialized examinations were performed for all members, including color fundus photography, fundus autofluorescence (FAF), and full field electroretinogram (ff-ERG) examination. The peripheral venous blood of all members was collected, and genomic DNA was extracted. Pathogenic genes and their loci were screened using whole exome high-throughput sequencing technology. Sanger sequencing was used to verify the pathogenic genes in the two pedigrees. The pathogenicity of candidate variants was evaluated according to the American Society for American College of Medical Genetics and Genomics (ACMG) classification criteria and guidelines for genetic variants. ResultsThe two probands were male, aged 9 and 7 years, respectively. The main complaint was poor binocular vision for 6 and 3 years and poor treatment effect of amblyopia. The proband (Ⅱ2) in family 1 had a pale red color on the optic disc, with leopard-like changes in the posterior pole and thinner retinal arteries. FAF showed mottled fluorescence attenuation outside the macular vascular arch. There was no significant waveform in both bright and dark visual responses of ff-ERG. He also had 6-toed deformity of both feet, renal cysts, and a slightly overweight body. The clinical diagnosis was non-pigmentary retinitis pigmentosa. The proband of family 2 (Ⅱ1) had poor binocular vision in a dark environment and had atrophy lesions on the nasal side of the optic disc and leopard print like changes in the fundus. FAF showed uneven enhancement in the fovea. ff-ERG showed severe abnormalities in dark and light response, with significant decrease and delay in b-wave amplitude and latency. He had no other systemic abnormalities. The clinical diagnosis was binocular RPSP. There were no abnormal ocular and systemic manifestations in the two family members. Gene sequencing revealed a homozygous mutation (c.534+1G>T) of BBS2 gene, which was inherited from the mother and father respectively. Based on clinical manifestations and genetic testing results, the final diagnosis was Bardet Biedl syndrome. The genetic sequencing results confirmed a novel compound heterozygous mutation (c.950T>G: p. Leu317Arg missense mutation and c.849+1G>C splicing mutation) of BBS7 gene. His father (Ⅰ1) and mother (Ⅰ2) carried M1 heterozygous variants. Combined with the clinical manifestations and genetic testing results, the final diagnosis was Bardet-Biedl syndrome (BBS). Family 2 proband (Ⅱ1) carried the BBS7 gene C.950T>G (p.Leu317Arg) (M2) missense variation and C.849 +1G>C (M3) splice site variation. His father (Ⅰ1) and mother (Ⅰ2) carried M3 shear site variation and M2 missense variation, respectively. The two families all fit the autosomal recessive inheritance pattern, and the genotype and clinical phenotype were coseparated. According to ACMG guidelines, M1, M2 and M3 were all identified as possible pathogenic variants. ConclusionsBBS2 gene M1 homozygous variation and BBS7 gene M2, M3 complex heterozygous variation are the possible pathogenic genes in family 1 and family 2, respectively. Two families are affected by BBS and RPSP, respectively.
Retinitis pigmentosa (RP) is a group of hereditary blinding fundus diseases caused by abnormalities in photoreceptors of the retina. RP is highly heterogeneous in hereditary and cdinical phenotypes. It can be divided into simple type RP and syndrome type RP. The main inheritance patterns are autosomal dominant, autosomal recessive inheritance and X-linked inheritance. With the popularization and clinical application of gene sequencing technology, more and more disease-causing genes have been discovered, and these genes are mainly expressed in photoreceptor cells and retinal pigment epithelial cell. ln-depth understanding of RP pathogenic genes not only provides a theoretical basis for RP diagnosis and genetic counseling, but also provides guidance for RP gene therapy.
ObjectiveTo identify the causative genes of the posterior microphthalmia-retinal pigment degeneration family. MethodsA retrospective clinical study. One child (proband) and 3 family members of a family with posterior microphthalmia-retinitis pigmentosa diagnosed by clinical and genetic examination at Henan Provincial People's Hospital in July 2019 were included in the study. Medical history and family history, and draw pedigree of the patients was collected. Visual acuity, visual field, fundus color photography, optical coherence tomography and electroretinogram (ERG) were examined. The peripheral venous blood of the proband, his parents and sister, and extract the whole genome DNA was collected. Whole-exome sequencing was used to detect genetic variations, the suspected pathogenic variations were verified by Sanger sequencing, and the pathogenicity was determined by bioinformatics analysis. ResultsThe parents discovered the proband was poor vision at the age of 10 months. At the age of 3, the best corrected visual acuity of the right eye and the left eye were 0.3 and 0.4, respectively. No abnormality was found in anterior segment. Extremely high hyperopia in both eyes. The axial length was 14.47 mm and 15.78 mm, respectively. The optic disc of both eyes was relatively small and flushed, retinal folds can be observed in macular area, and no obvious pigment deposition was found. ERG examination showed that the rod system response and the maximal combined response of both eyes decreased slightly to moderately, and the single-flash cone response and the 30 Hz flicker response decreased moderately to severely. Genetic analysis revealed two novel mutations in the membrane frizzled-related protein (MFRP) gene in the proband: c.363delC/p.Thr121Thrfs*16, c.1627C＞T/p .Gln543Stop,37 in exon 4 and 13, the former was a frameshift mutation, encoding 16 amino acids and then terminated, and the latter was an nonsense mutation, truncated 37 amino acids, both which were predicted to be pathogenic and segregate with disease. The mother and sister carried c.363delC, and the father carried c.1627C＞T. ConclusionMFRP gene c.363delC/p.Thr121Thrfs*16, c.1627C＞T/p.Gln543Stop, 37 compound heterozygous mutation may be the pathogenic gene of this family.
Retinitis pigmentosa (RP) is an inherited retinal disease characterized by degeneration of retinal pigment epithelial cells. Precision medicine is a new medical model that applies modern genetic technology, combining living environment, clinical data of patients, molecular imaging technology and bio-information technology to achieve accurate diagnosis and treatment, and establish personalized disease prevention and treatment model. At present, precise diagnosis of RP is mainly based on next-generation sequencing technology and preimplantation genetic diagnosis, while precise therapy is mainly reflected in gene therapy, stem cell transplantation and gene-stem cell therapy. Although the current research on precision medicine for RP has achieved remarkable results, there are still many problems in the application process that is needed close attention. For instance, the current gene therapy cannot completely treat dominant or advanced genetic diseases, the safety of gene editing technology has not been solved, the cells after stem cell transplantation cannot be effectively integrated with the host, gene sequencing has not been fully popularized, and the big data information platform is imperfect. It is believed that with the in-depth research of gene sequencing technology, regenerative medicine and the successful development of clinical trials, the precision medicine for RP will be gradually improved and is expected to be applied to improve the vision of patients with RP in the future.
Objective To observe the characteristics of fundus autofluorescence (AF) in short wavelength AF (SW-AF) and Near Infrared AF (NIR-AF), and their relationship with visual fields. Methods Twelve patients (24 eyes) with primary RP were enrolled in this study. The patients included nine males (18 eyes) and three females (six eyes). The patients aged from 15 to 69 years, with a mean age of (35.33plusmn;15.03) years. All the patients were examined for color photography, SW-AF, NIR-AF, visual fields and optical coherence tomography examination. Results There were hyper-AF ring of varying sizes in posterior pole by SW-AF and NIR-AF examinations. The area of hypo-AF which located in SW-AF hyper-AF ring had a positive correlation with the area of hyper-AF in the NIR-AF (r=0.662，P＜0.05). OCT showed that outside the hyper-AF ring, there were disconnected inner segment/outer segment (IS/OS) junction and external limiting membrane, and thinned outer nuclear layer and retinal pigment epithelium. Peripheral retinal osteocytes-like pigmentation showed non fluorescence in SW-AF and NIR-AF. The plaque-like area showed mottled and low fluorescence examined by SW-AF. SW-AF hyper-AF ring had a positive correlation with visual fields (r=0.492，P＜0.05). Conclusions The area of hypo-AF inside of the SW-AF hyper-AF ring is related to visual fields in RP patients. The retinal structures in the hypo-AF area inside of the SW-AF hyper-AF ring, and in the NIR-AF hyper-AF region are normal.