OBJECTIVE: To explore the mechanism of BNIP3-mediated mitophagy in m.3635G>A related Leber's hereditary optic neuropathy (LHON). METHODS: A trans-mitochondrial cybrid cell line derived from a Chinese LHON patient carrying the m.3635G>A, diagnosed at the Eye Hospital of Wenzhou Medical University in September 2013, was selected as the study subject. A trans-mitochondrial cybrid cell line from a healthy control with an identical mitochondrial background was included as a control. Immunofluorescence, real-time quantitative PCR (RT-qPCR), and Western blotting were employed to assess the expression of autophagy-related proteins, aiming to explore the role of BNIP3-mediated mitophagy in m.3635G>A related LHON. This study was approved by the Medical Ethics Committee of the Eye Hospital of Wenzhou Medical University (Ethics No. 2023-J-096). RESULTS: Compared with the control group, the protein expression levels of autophagy-related markers LC3 (LC3-II/LC3-I) and LAMP1 were significantly reduced in the variant group (P < 0.05). Additionally, the protein levels of macroautophagy-related proteins ATG12, ATG7, and ATG5 were also significantly decreased (P < 0.05). Compared with the control cells, the mRNA and protein expression levels of mitophagy-associated protein BNIP3 were significantly reduced in the cells of the variant group (P < 0.05). Compared with the control group, both mRNA and protein expression levels of the mitophagy-related protein BNIP3 were significantly reduced in the variant group (P < 0.05). CONCLUSION The m.3635G>A inhibits BNIP3-mediated mitophagy, thereby contributing to the pathogenesis of LHON.
Humans ; Proto-Oncogene Proteins/metabolism* ; Mitophagy/genetics* ; Membrane Proteins/metabolism* ; Optic Atrophy, Hereditary, Leber/metabolism* ; Mitochondria/metabolism* ; Cell Line ; Male

OBJECTIVE: To explore the genetic basis of a patient with suspected Oculocutaneous albinism (OCA). METHODS: An OCA patient presented at the West China Second Hospital of Sichuan University and his mother were selected as the study subjects. Peripheral blood samples were collected for the extraction of, genomic DNA, and whole exome sequencing (WES) was carried out. Candidate variants were verified through specific primer amplification, Sanger sequencing, and agarose gel electrophoresis. Bioinformatic analysis and pathogenicity rating were conducted on the candidate variants. This study has been approved by the Medical Ethics Committee of West China Second Hospital (No. 2024-228). RESULTS: Genetic testing revealed that the patient had harbored variants in exon 1 of the TYR gene, including a c.157G>T (p.G53C) missense variant and a c.609dup (p.A204fs) frameshifting variant. Specific primer amplification and Sanger sequencing, combined with agarose gel electrophoresis, confirmed that these are compound heterozygous variants. Based on the guidelines from the ACMG, the c.157G>T was rated as likely pathogenic, and c.609dup was rated as pathogenic. Alphafold3 predicted that the variant proteins had significant structural changes. CONCLUSION The patient was diagnosed with OCA due to compound heterozygous variants of the TYR gene. Discovery of the c.609dup variant has enriched the mutational spectrum of OCA and provided a basis for genetic counseling and prenatal diagnosis for this patient.
Humans ; Albinism, Oculocutaneous/enzymology* ; Male ; Female ; Monophenol Monooxygenase/chemistry* ; Base Sequence ; Mutation, Missense

OBJECTIVE: To explore the clinical phenotype, genotype and genetic characteristics for a patient with unilateral Pigmented paravenous retinochoroidal atrophy (PPRCA) and Retinitis pigmentosa (RP) in the contralateral eye. METHODS: A PPRCA pedigree which had presented at the Department of Medical Genetics of the Eye Hospital of Wenzhou Medical University in August 2021 was selected as the study subject. Clinical data of the family members were collected. The proband underwent wide-field fundus photography, wide-field autofluorescence, full-field electroretinogram (ff-ERG), visual field testing, optical coherence tomography (OCT), and fundus angiography (FFA and ICGA). Blood samples were collected from the proband and family members (parents and two sisters), and buccal mucosal cells were collected from the proband's daughter, and genomic DNA was extracted for each family member. Whole exome sequencing (WES) was performed on the proband. Candidate variants were verified using Sanger sequencing and pathogenicity analysis. This study was approved by the Medical Ethics Committee of the Eye Hospital of Wenzhou Medical University (Ethics No. 2019-134). RESULTS: Wide-angle fundus photography and autofluorescence showed that the right eye was consistent with PPRCA and the left eye with RP. OCT showed that the outer layer of the fovea was intact in the right eye, while disorganized outer segment was found in the fovea of the left eye, and outer segment atrophies outside the fovea were found in both eyes. The amplitudes of ff-ERG decreased significantly in both eyes, and the amplitudes in right eye were slightly higher than those of the left eye. Visual field showed a paracentral arcuate scotoma in the right eye and severe centripetal contraction in the left eye. FFA showed hyperfluorescence in the retinal vein distribution area caused by atrophy of retinal pigment epithelium of the right eye and hypofluorescence related to bone spicule pigmentation, in addition with mottled hypofluorescence of choroid in the left eye. ICGA showed mild paravenous retinochroidal atrophy of the right eye and diffuse choroid capillaries atrophy in the middle and peripheral area of the left eye. WES revealed that the proband had a heterozygous c.2234C>T (p.Thr745Met) variant of the CRB1 gene. Sanger sequencing confirmed that the proband and family members except the father of the proband carried the same CRB1 gene variant. Based on the criteria and guidelines for the classification of genetic variation and related consensus from the American College of Medical Genetics and Genomics (ACMG), this variant was classified as pathogenic (PM3_VeryStrong+PM1+PM2_Supporting +PP3). CONCLUSION The heterozygous c.2234C>T (p.Thr745Met) variant of the CRB1 gene may underlay the unilateral PPRCA with contralateral eye RP in this proband. Above findings have enriched the mutational spectrum of the CRB1 gene.
Humans ; Electroretinography ; Exome Sequencing ; Eye Proteins/genetics* ; Membrane Proteins/genetics* ; Mutation ; Nerve Tissue Proteins/genetics* ; Pedigree ; Phenotype ; Retinitis Pigmentosa/genetics* ; Tomography, Optical Coherence ; Retinal Degeneration ; Eye Diseases, Hereditary

Background and Objective: The Philippines does not have a national congenital rubella syndrome (CRS) surveillance or registry. Regular monitoring of CRS cases in hospitals, including in a Philippine tertiary hospital, helped in the past to provide clinico-epidemiologic data on CRS. This study aimed to continue providing clinico-epidemiologic data on CRS cases seen in the Philippine tertiary hospital from 2009-2012 and 2019-2022 and compare the cases seen from said timelines. Methods: A cross-sectional study was used, employing chart review of patients newly diagnosed with CRS from 2009-2012 and 2019-2022 in the Department of Ophthalmology and Visual Sciences at the Philippine tertiary hospital. Results: Forty-two patients newly diagnosed with CRS from 2009-2012 and 2019-2022 were included. Only 14 (33%) were serologically-confirmed cases (albeit qualitatively). Median age (first and third interquartile ranges) at consult was 1 year (0.4, 2.5). Twenty-four (57%) patients had maternal history of rashes and/or fever. Trimester of pregnancy when mother became symptomatic was not significantly correlated with chief complaint (p=0.20) and numbers of ophthalmic (p=0.68) and systemic manifestations (p=0.32). Cataract was the most common ophthalmic manifestation present in 40 (95%) patients. Twenty-six (62%) patients had other associated systemic findings of which hearing loss was the most common. Only 29 of 40 patients with cataract underwent lensectomy, with 23 patients having poor visual prognosis prior to surgery (5 with nystagmus alone, 10 with nystagmus and strabismus, and 8 with strabismus alone). Discussion: Using ophthalmic manifestations as primary indicator, this study provided an update on the CRS cases in the country. Laboratory confirmation remains a challenge in diagnosing CRS as the tests are costly and not widely available. There was increase from 2009-2012 compared to 2019-2022 in number of patients who underwent surgical treatment for cataract but visual outcomes were suboptimal due to delay in consultation. Although there was a decrease in number of CRS cases seen in the Philippine tertiary hospital, this cannot be attributed to increased rubella-containing vaccine (RCV) coverage alone. Conclusion Provision of data from individual hospital-based studies similar to this highlights the need for a national CRS surveillance system or registry. This can better gauge the burden of CRS and identify the gap in RCV coverage.
Rubella Syndrome, Congenital ; Retinitis Pigmentosa

OBJECTIVES

To determine the phenotypic and genotypic characterization of individuals with retinitis pigmentosa (RP), identify their genetic etiologies, and provide counseling to affected patients.

This non-interventional, observational study evaluated 18 patients with clinically-diagnosed RP from 15 different families. The patients underwent complete ophthalmological examination with retinal functional and morphologic assessment. Genetic testing was done using next-generation sequencing.

Ten gene mutations with 22 variants were identified. The inheritance pattern was predominantly autosomal recessive (70%). The most common mutation was EYS (27.8%). One possible novel gene, RGS7, and novel variants of CNGB1 were identified. Characteristic RP profiles were observed, with syndromic findings noted in USH2A and BBS5 mutations.

Phenotypic characteristics among different gene mutations have distinct features. This is the first study in the country to demonstrate the genotypic heterogeneity of RP, displaying 22 variants with 3 noted novel mutations.

To summarize the clinical diagnosis and treatment process and genetic test results and characteristics of one child with Angelman syndrome (AS) complicated with oculocutaneous albinism type 2 (OCA2), and to review the literature. "Angelman syndrome" "P gene" and "Oculocutaneous albinism type 2" were used as keywords to search at CNKI, Wanfang, and PubMed databases (from creation to December 2019). Then all the patients were analyzed. The patient in this study was a girl aged 1 year. After birth, she was found to present as white body, yellow hair, and nystagmus. She could raise her head at the age of 2 months and turn over at the age of 7 months. The head circumference was 42 cm and she could not sit alone or speak at present. Trio-based exome sequencing revealed that the patient carried a homozygous mutation of c.168del (p.Gln58ArgfsTer44) in the P gene, and her father was heterozygous and her mother was wild-type. The detection of copy number variation showed deletion on the maternal chromosome at 15q11.2-13.1 region (P gene located in this region) in the patient. Until December 2019, a total of 4 cases in the 4 literature had been reported. Adding our case here, the 5 cases were summarized and found that all the cases showed white skin, golden hair, and shallow iris after birth. Comprehensive developmental delay was found around 6 months of age after birth, and the language remained undeveloped in 2 cases till follow-up into childhood. Seizures occurred in 4 patients. Two cases had ataxia. All the 5 cases had acquired microcephaly. Two cases had a family history of albinism. Electroencephalogram monitoring was completed in 3 cases and the results were abnormal. Genetic tests showed that all the 5 cases had deletion on maternal chromosome at 15q11-13 region. Four cases carried mutation of P gene on paternal chromosome. And 1 case was clinically diagnosed as OCA2 without P gene test. AS combined with OCA2 is relatively rare. OCA2 is easily diagnosed based on the obvious clinical manifestations after birth. When combined with clinical manifestations such as neurodevelopmental delay, it might indicate the possibility of AS that is hardly diagnosed clinically at an early stage. Genetic tests can reveal the cross-genetic phenomenon of AS and OCA2 and the complex of them can be eventually diagnosed.
Female ; Humans ; Albinism, Oculocutaneous/genetics* ; DNA Copy Number Variations ; Membrane Transport Proteins/genetics* ; Molecular Biology ; Mutation ; Infant

OBJECTIVE: To explore the genetic basis for a patient with early-onset retinitis pigmentosa (RP). METHODS: A patient who had presented at the West China Hospital of Sichuan University on March 10, 2020 was selected as the study subject. The patient and his parents were subjected to whole exome sequencing (WES). Candidate variants were verified by Sanger sequencing and in silico analysis. RESULTS: The patient has featured substantial loss of binocular vision field. Funduscopy revealed characteristic bone spicule-type pigment deposits, as well as attenuated retinal arterioles and pale-appearing optic discs. WES revealed that he has harbored compound missense variants of a RP-associated CRB1 gene, including c.2969T>C (p.Leu990Ser) and c.1816T>C (p.Cys606Arg), which were respectively inherited from his father and mother. Homozygous c.1816T>C (p.Cys606Arg) variant has been identified among RP patients, whilst the c.2969T>C (p.Leu990Ser) variant was unreported previously. Both variants were predicted as likely pathogenic based on the guidelines from the American College of Medical Genetics and Genomics (ACMG). CONCLUSION The novel compound heterozygous variants of the CRB1 gene probably underlay the early-onset RP in this patient. Above finding has enriched the mutational spectrum of the CRB1 gene.
Male ; Female ; Humans ; China ; Genomics ; Homozygote ; Mothers ; Retinitis Pigmentosa/genetics* ; Eye Proteins/genetics* ; Membrane Proteins/genetics* ; Nerve Tissue Proteins/genetics*

OBJECTIVE: To explore the clinical and genetic characteristics of a patient with Hermansky-Pudlak syndrome type 5 (HPS-5). METHODS: A child with HPS-5 who had attended the Children's Hospital Affiliated to Shandong University on October 3, 2019 was selected as the study subject. Clinical data of the child were collected. Genetic variant was analyzed through high-throughput sequencing. A literature review was also carried out. RESULTS: The child, a 1-year-and-5-month-old girl, had nystagmus since childhood, lost of retinal pigmentation by fundus examination and easy bruising. High-throughput sequencing revealed that she has harbored compound heterozygous variants of the HPS5 gene, namely c.1562_1563delAA (p.F521Sfs*27) and c.1404C>A (p.C468X), which were inherited from his father and mother, respectively. Based on the guidelines from the American College for Medical Genetics and Genomics (ACMG), both variants were predicted to be pathogenic (PVS+PM2_Supporting+PM3+PP4). Among 18 previously reported HPS-5 patients, all had had eye problems, and most of them had tendency for bleeding. Eight cases had carried compound heterozygous variants of the HPS5 gene, 8 carried homozygous variants, 2 carried double homozygous variants, and most of them were null mutations. CONCLUSION The c.1562_1563delAA(p.F521Sfs*27) and c.1404C>A (p.C468X) compound heterozygous variants of the HPS5 gene probably underlay the HPS-5 in this child. High-throughput sequencing has provided an important tool for the diagnosis. HSP-5 patients usually have typical ocular albinism and/or oculocutaneous albinism and tendency of bleeding, which are commonly caused by compound heterozygous and homozygous variants of the HPS5 gene, though serious complications have been rare.
Female ; Humans ; Infant ; Hermanski-Pudlak Syndrome/pathology* ; High-Throughput Nucleotide Sequencing ; Mutation

OBJECTIVE: We wanted to investigate the radial peripapillary capillary (RPC) network in patients with Bietti crystalline dystrophy (BCD). METHODS: We compared RPC densities in the disk and different peripapillary regions, obtained using optical coherence tomography angiography in 22 patients with BCD (37 eyes) and 22 healthy subjects (37 eyes). The BCD group was then divided into Stage 2 and Stage 3 subgroups based on Yuzawa staging, comparing the RPC densities of the two. RESULTS: The disk area RPC density was 38.8% ± 6.3% in the BCD group and 49.2% ± 6.1% in the control group ( P < 0.001), and peripapillary region RPC density was significantly lower in the BCD group than in the control group (49.1% ± 4.7% and 54.1% ± 3.0%, respectively, P < 0.001). There were no significant RPC density differences between the tempo quadrant and inside disk of Stages 2 and 3 subgroups; the other areas showed a significantly lower RPC density in Stage 3 than in Stage 2 BCD. CONCLUSION The BCD group RPC density was significantly lower than the control group. The reduction of RPC density in the tempo quadrant occurred mainly in the Stage 1 BCD. In contrast, the reduction of RPC density in superior, inferior, and nasal quadrants occurred mainly in Stage 2.
Adult ; Aged ; Angiography ; Corneal Dystrophies, Hereditary/physiopathology* ; Female ; Humans ; Male ; Microvascular Density ; Microvessels/physiopathology* ; Middle Aged ; Retinal Diseases/physiopathology* ; Retinal Vessels/physiopathology* ; Tomography, Optical Coherence

OBJECTIVE: To explore the genetic basis for a Chinese patient with retinitis pigmentosa (RP). METHODS: Whole exome sequencing (WES) was carried out to screen potential variant in the proband. Candidate variants were determined by taking consideration of clinical phenotype. Sanger sequencing was used to verify the variant in the proband and his parents. RESULTS: The proband was found to harbor compound heterozygous variants of c.8G>A (p.Cys3Tyr) and c.958_959insA (p.Arg320Glnfs*29) in the C2ORF71 gene, which has derived from his father and mother, respectively. Both variants were unreported previously. Based on the ACMG guidelines, they were predicted to be likely pathogenic and pathogenic, respectively. CONCLUSION The novel compound heterozygous variants of the C2ORF71 gene probably underlay the pathogenesis of RP in the proband. Above finding has enriched the spectrum of C2ORF71 gene mutations and facilitated genetic counseling for the family.
Asians/genetics* ; China ; Humans ; Mutation ; Pedigree ; Retinitis Pigmentosa/genetics* ; Whole Exome Sequencing