Identification and characterization of a new pathologic mutation in a large Leber hereditary optic neuropathy pedigree.

BACKGROUND: Most patients suffering from Leber hereditary optic neuropathy carry one of the three classic pathologic mutations, but not all individuals with these genetic alterations develop the disease. There are different risk factors that modify the penetrance of these mutations. The remaining patients carry one of a set of very rare genetic variants and, it appears that, some of the risk factors that modify the penetrance of the classical pathologic mutations may also affect the phenotype of these other rare mutations. RESULTS: We describe a large family including 95 maternally related individuals, showing 30 patients with Leber hereditary optic neuropathy. The mutation responsible for the phenotype is a novel transition, m.3734A > G, in the mitochondrial gene encoding the ND1 subunit of respiratory complex I. Molecular-genetic, biochemical and cellular studies corroborate the pathogenicity of this genetic change. CONCLUSIONS: With the study of this family, we confirm that, also for this very rare mutation, sex and age are important factors modifying penetrance. Moreover, this pedigree offers an excellent opportunity to search for other genetic or environmental factors that additionally contribute to modify penetrance.

Late retinal and optic nerve vascular complications due to COVID-19 in young individuals.

PURPOSE: This study aims to describe the late retinal and optic nerve vascular complications due Coronavirus disease 2019 (COVID-19) in a Spanish young population. METHODS: We describe 15 eyes of 15 young patients without any other systemic risk factors, except controlled arterial hypertension in 5 of them, with the diagnosis of Central retinal vein occlusion (CRVO), Branch retinal vein occlusion (BRVO), Central retinal artery occlusion (CRAO), Branch retinal artery occlusion (BRAO), Mixed occlusions (Artery and Vein) and Non-arteritic ischemic optic neuropathy (NAION) with a previous COVID-19 infection demonstrated with a positive COVID-19 IgG Test (COVID-19 IgG/IgM Rapid Test Cassette, Lambra Laboratories, Madrid, Spain. RESULTS: 9 males and 6 females, with a mean age of presentation of 49.7 ± 9 years old were included. The mean time between infection and diagnosis of the disease was 3.5 ± 1.2 months. The most common retinal or optic nerve vascular complication was CRVO (6 cases), following by CRAO (4 cases), Mixed arterial and venous occlusions (2 cases), NAION (2 cases) and BRAO (1 case). CONCLUSIONS: The presence of a retinal or optic nerve vascular event in a young patient without any other hypercoagulable or genetic thrombophilic disorder, should make us rule out a previous COVID-19 infection. Ophthalmologists must be awared that retinal circulation could be another potential site for thromboembolic and optic nerve circulatory insufficiency complications of COVID-19. To our knowledge, this is the longest case series of retinal or optic nerve vascular events described after COVID-19 infection.

Targeted Analysis of Tears Revealed Specific Altered Metal Homeostasis in Age-Related Macular Degeneration.

Purpose: Specific altered metal homeostasis has been investigated in the tear film of age-related macular degeneration (AMD) patients considering that metal dyshomeostasis contributes to the production of free radicals, inflammation, and apoptosis and results in conformational changes of proteins. Methods: A multitargeted approach based on spectrophotometry and mass spectrometry techniques has been implemented to the multiplexed quantitation of lactoferrin (LF), S100 calcium binding protein A6 (S100A6), metallothionein 1A (MT1A), complement factor H (CFH), clusterin (CLU), amyloid precursor protein (APP), Mg, P, Na, Fe, Cu, Zn, and Ca, in the tear film from 60 subjects, 31 patients diagnosed with the dry form of AMD, and 29 healthy individuals. Results: Significant up-regulations of MT1A (1.9-fold) and S100A6 (1.4-fold) and down-regulations of LF (0.7-fold), Fe (0.6-fold), Mg (0.7-fold), and Cu (0.7-fold) were observed in AMD patients, when compared to control subjects. Of all the studied variables, only APP showed negative correlation with age in the AMD group. Also, positive correlations were observed for the variables Mg and Na, Cu and Mg, and P and Mg in both the AMD and control groups, whereas positive correlations were exclusively determined in the AMD group for Cu and LF, Na and Ca, and Mg and Ca. The panel constituted of MT1A, Na, and Mg predicts AMD disease in 73% of cases. Conclusions: The different levels of target metals and (metallo-)proteins in the tear film suggest altered metal homeostasis in AMD patients. These observed pathophysiological changes may be related with the anomalous protein aggregation in the macula.

Association Study of MTHFR Polymorphisms with Nonarteritic Anterior Ischemic Optic Neuropathy in a Spanish Population.

INTRODUCTION: Nonarteritic anterior ischemic optic neuropathy (NAION), painless loss of central and/or peripheral vision, is a multifactorial disease caused by insufficient blood flow through the posterior ciliary arteries to the optic nerve head. Mutations in the methylenetetrahydrofolate reductase (MTHFR) gene, triggering hyperhomocysteinemia as a consequence of a decreased activity of the codified enzyme, have been considered to be among the risk factors of NAION. OBJECTIVE: The main aim was to study the association of the most common MTHFR genetic polymorphisms C677T and A1298C with NAION in a Spanish population. METHODS: In this case-control study, the association of the most common MTHFR polymorphisms was investigated in 94 unrelated native Spanish patients diagnosed with NAION and 204 healthy controls. Two single nucleotide polymorphisms located in the MTHFR gene, C677T (rs1801133) and A1298C (rs1801131), were analyzed by DNA sequencing and TaqMan assays. RESULTS: The allelic and genotypic frequencies of the MTHFR variants obtained in the NAION group were not significantly different when compared with the control group. A higher frequency of the C677T/A1298C genotype, codifying the nonmutated MTHFR form, was obtained in control subjects (11.27%) compared to NAION patients (4.26%), suggesting a protective effect of the wild-type protein, although this result was not conclusive considering the obtained confidence interval (CI) (95% CI: 0.13-1.06). Study of additional clinical factors including hypertension, diabetes mellitus, and dyslipidemia showed no association with a higher risk of NAION. Conversely, the clinical history of heart or cerebrovascular diseases was significantly higher in NAION patients compared to controls. Over the world, risk variants of the MTHFR gene are highly frequent, excluding African black populations, indicating a racial influence. CONCLUSIONS: The MTHFR variants did not significantly increase the risk of suffering from NAION. However, considering that individuals with at least one of the risk variants have the MTHFR enzyme with decreased activity, it cannot be ruled out that these mutations are relevant for the development of NAION in a subgroup of the population with other specific characteristics. These may include high plasma levels of homocysteine along with nutritional deficiencies including low folate or vitamin B12 and the combination of systemic and local risk factors.

The Use of Vitamins and Coenzyme Q10 for the Treatment of Vascular Occlusion Diseases Affecting the Retina.

Nutritional supplementation with antioxidants and vitamins is widely recommended in the treatment of vascular disorders affecting the retina, although there is insufficient evidence on its effectiveness. The vitamin-like compound coenzyme Q10 (CoQ10) is a nutritional supplement of current interest to treat neurodegenerative diseases. Here, we report a retrospective clinical case series study of 48 patients diagnosed with retinal vascular diseases, including non-arteritic ischemic optic neuropathy (NAION), retinal artery occlusion (RAO), and homonymous hemianopia or quadrantanopia following stroke, treated with oral supplementation with CoQ10 (100 mg per day) and vitamins. Patient follow-up was performed using the Humphrey field analyzer and 30-2 testing algorithm to determine the visual field index (VFI) and progression rates. All treated patients showed positive VFI progression rates per year: +11.5 ± 15% for NAION patients (n = 18), +22 ± 17% for RAO patients (n = 7), +9.3 ± 10.5% for hemianopia/quadrantanopia patients (n = 10), and +11 ± 21% for patients with other conditions (n = 13). The interruption of CoQ10 supplementation in one patient resulted in a pronounced decrease of the VFI, which was partially recovered when treatment was restored. This study supports the role of CoQ10 as a nutritional therapeutic agent for vascular diseases affecting the retina. Owing to decreased VFI after interruption of CoQ10, its beneficial effects may be reversible.

The association study of lipid metabolism gene polymorphisms with AMD identifies a protective role for APOE-E2 allele in the wet form in a Northern Spanish population.

PURPOSE: To elucidate the potential role of eleven single nucleotide polymorphisms (SNPs) in the most relevant lipid metabolism genes in Northern Spanish patients with age-related macular degeneration (AMD). METHODS: A case-control study of 228 unrelated native Northern Spanish patients diagnosed with AMD (73 dry and 155 wet) and 95 healthy controls was performed. DNA was isolated from peripheral blood and genotyped for the SNPs APOE rs429358 and rs7412; CTEP rs3764261; LIPC rs10468017 and rs493258; LPL rs12678919; ABCA1 rs1883025; ABCA4 rs76157638, rs3112831 and rs1800555; and SCARB1 rs5888, using TaqMan probes. An additional association study of ε2, ε3 and ε4 major isoforms of APOE gene with AMD has been carried out. RESULTS: The allele and genotype frequencies for each of the eleven sequence variants in the lipid metabolism genes did not show significant differences when comparing AMD cases and controls. Statistical analysis revealed that APOE-ε2 carrier genotypes were less frequently observed in patients with wet AMD compared to controls (5.8% versus 13.7%, respectively: p = 3.28 × 10-2 ; OR = 0.42, 95% CI: 0.19-0.95). The frequency of the allele T of rs10468017 (LIPC gene) was lower in dry AMD cases compared to controls (15.8 versus 27.9%, respectively: p = 8.4 × 10-3 OR = 0.57, 95% CI: 0.33-0.98). CONCLUSIONS: Our results suggest a protective role for APOE-ε2 allele to wet AMD in the Northern Spanish population.

Comprehensive genomic diagnosis of inherited retinal and optical nerve disorders reveals hidden syndromes and personalized therapeutic options.

PURPOSE: In the era of precision medicine, genomic characterization of blind patients is critical. Here, we evaluate the effects of comprehensive genetic analysis on the etiologic diagnosis of potentially hereditary vision loss and its impact on clinical management. METHODS: We studied 100 non-syndromic and syndromic Spanish patients with a clinical diagnosis of blindness caused by alterations on the retina, choroid, vitreous and/or optic nerve. We used a next-generation sequencing (NGS) panel (OFTALMOgenics™), developed and validated within this study, including up to 362 genes previously associated with these conditions. RESULTS: We identified the genetic cause of blindness in 45% of patients (45/100). A total of 28.9% of genetically diagnosed cases (13/45) were syndromic and, of those, in 30.8% (4/13) extraophthalmic features had been overlooked and/or not related to visual impairment before genetic testing, including cases with Mainzer-Saldino, Bardet-Biedl, mucolipidosis and MLCRD syndromes. In two additional cases-syndromic blindness had been proposed before, but not specifically diagnosed, and one patient with Heimler syndrome had been misdiagnosed as an Usher case before testing. 33.3% of the genetically diagnosed patients (15/45) had causative variants in genes targeted by clinical trials exploring the curative potential of gene therapy approaches. CONCLUSION: Comprehensive genomic testing provided clinically relevant insights in a large proportion of blind patients, identifying potential therapeutic opportunities or previously undiagnosed syndromes in 42.2% of the genetically diagnosed cases (19/45).

Coenzyme Q10 treatment improved visual field after homonymous quadrantanopia caused by occipital lobe infarction.

PURPOSE: To report the clinical findings and management of a case of occipital lobe infarction with homonymous quadrantanopia in a patient treated with vitamins and coenzyme Q10. OBSERVATIONS: A currently 69-years-old patient presenting in 2007 left inferior quadrantanopia following a right occipital lobe stroke with initial visual field index of 82% and 79% in the right and left eyes, respectively. From 2007 to 2010 was treated with vitamin and antioxidant complexes, without specific signs of changes observed in the visual field (81% right eye, 79% left eye). In 2011 was treated for the first time with coenzyme Q10 (Active complex® Q10 Gold 100 mg) in addition to the vitamin and antioxidant supplementation. A promptly slight improvement of the visual field in both eyes was observed. In 2013, a remarkable improvement was noticed observing a slight scotoma where previously presented the quadrantanopia. Thereafter, in the successive one-year follow-up examinations the patient experienced an exponential improvement in the visual field with gradually fading of the scotoma. Currently the patient no longer presents any sign of quadrantanopia, with normal visual field in both eyes (99% right eye, 98% left eye). CONCLUSION AND IMPORTANCE: Spontaneous improvement more than 6 months after stroke is thought to be unlikely. However, we observed, for the first time, an amelioration of the visual field after 10 years of an occipital lobe stroke. The combination of vitamins and coenzyme Q10 (100 mg) improved the prognosis with significant recovery of the visual field, which is impossible to recover under current knowledge.

Association study of high-frequency variants of MTHFR gene with retinal vein occlusion in a Spanish population.

Background: To study the association of the most common methylenetetrahydrofolate reductase (MTHFR) genetic polymorphisms C677T and A1298C with retinal vein occlusion (RVO) in a Spanish population. Methods: Case-control study involving 359 subjects, 183 unrelated native Spanish patients diagnosed with RVO, distributed in central or branch RVO, and 176 healthy controls. Two SNPs located in the gene MTHFR, C677T (rs1801133) and A1298C (rs1801131) were analyzed by DNA sequencing and TaqMan assays. Results: A high prevalence of the MTHFR variants T and C of the SNP C677T and A1298C, respectively, was observed in our population. Specifically, 88.07% of controls and 85.25% of RVO patients have at least one of these variants. However, the prevalence of these variants was not significantly different when comparing RVO patients and controls. The variant T of C677T was identified in 60.65% of RVO patients and 59.10% of control subjects, while the variant C of A1298C was present in 46.45% of RVO patients and 51.14% of controls. No association of dyslipidemia, diabetes mellitus, glaucoma, thyroid disease and renal disease with RVO was observed, while hypertension was significantly higher in the RVO patients (p < .0001). Conclusions: The MTHFR variants, T of C677T and C of A1298C, did not significantly increase the risk of suffering RVO in a Spanish population and therefore additional risk factors are contributing to the onset of the disease.

Metallothionein polymorphisms in a Northern Spanish population with neovascular and dry forms of age-related macular degeneration.

BACKGROUND: To elucidate the potential role of single nucleotide polymorphisms (SNPs) in the metallothionein (MT) genes in Northern Spanish patients with age-related macular degeneration (AMD). METHODS: A total of 130 unrelated Northern Spanish natives diagnosed with AMD (46 dry, 35 neovascular, and 49 mixed) and 96 healthy controls, matched by age and ethnicity, were enrolled in a case-control study. DNA was isolated from peripheral blood and genotyped for 14 SNPs located at 5 MT genes (MT1A: rs11076161, rs 11640851, rs8052394, and rs7196890; MT1B: rs8052334, rs964372, and rs7191779; MT1M: rs2270836 and rs9936741; MT2A: rs28366003, rs1610216, rs10636, and rs1580833; MT3: rs45570941) using TaqMan probes. The association study was performed using the HaploView 4.0 software. RESULTS: The allelic and genotypic frequencies analysis revealed that rs28366003 at MT2A gene is significantly associated with dry AMD. The frequency of genotype AG was significantly higher in dry AMD than in control cases (p = 2.65 × 10-4; AG vs. AA) conferring more than ninefold increased risk to dry AMD (OR = 9.39, 95% CI: 2.11-41.72), whereas the genotype AA confers disease protection (OR = 0.82, 95% CI: 0.71-0.95). No statistically significant differences were observed between AMD subjects and controls in the rest of the 14 SNPs analyzed. CONCLUSIONS: The present study is the first to investigate the potential association of SNPs at MT genes with susceptibility to AMD. We found a significant association of SNP rs28366003 at MT2A gene with susceptibility to the dry form of AMD in a Northern Spanish population.

Blockade of Tumor Necrosis Factor-Alpha: A Role for Adalimumab in Neovascular Age-Related Macular Degeneration Refractory to Anti-Angiogenesis Therapy?

AIMS: To report a case of wet age-related macular degeneration (wet-AMD) refractory to intravitreal anti-vascular endothelial growth factor (anti-VEGF) therapy in a patient who showed visual and anatomical improvement and stabilization after starting a subcutaneous treatment course with adalimumab, an anti-tumor necrosis factor-alpha (TNF-α) drug, for concomitant Crohn's disease. METHODS: Observational case report of a female patient. Ophthalmological evaluation was performed by slit lamp and ophthalmoscopy (posterior pole and anterior segment). Best-corrected visual acuity (BCVA) was determined, and imaging was performed by fluorescein angiography, indocyanine green angiography, and optical coherence tomography (OCT). Intravitreal therapies used and treatment with anti-TNF-α were recorded. RESULTS: A 64-year-old woman with wet-AMD was treated with fourteen intravitreal injections of ranibizumab (0.5 mg) for a period of 40 months with intervals of 1-6 months. She initially showed a good visual and anatomical response to periodic anti-VEGF treatment but during check visits, anatomical and functional responses deteriorated. At the 40-month follow-up, the patient had developed Crohn's disease, and her rheumatologist started treatment with adalimumab (40 mg subcutaneously every 2 weeks). During the 25 months of treatment with adalimumab, the patient did not require any additional intravitreal anti-VEGF treatments because her BCVA, clinical, and OCT findings improved and remained stable. CONCLUSIONS: We described a case of a patient with wet-AMD refractory to anti-VEGF therapy, which clinically benefited from subcutaneous adalimumab therapy. Treatment with subcutaneous anti-TNF-α in combination with anti-VEGF therapy avoids the high cost and risks related to multiple intravitreal anti-VEGF injections with good functional and anatomic outcomes.

CFH polymorphisms in a Northern Spanish population with neovascular and dry forms of age-related macular degeneration.

PURPOSE: To elucidate the potential role of single-nucleotide polymorphisms (SNPs) in complement factor H (CFH) gene in Northern Spanish patients with age-related macular degeneration (AMD). METHODS: A case-control study of 130 unrelated native Northern Spanish diagnosed with AMD (46 dry, 35 neovascular and 49 mixed) and 96 healthy controls matched by age and ethnicity were enrolled. DNA was isolated from peripheral blood and genotyped for AMD-associated SNPs (rs3753394, rs529825, rs800292, rs3766404, rs203674, rs10671170, rs3753396 and rs1065489) using TaqMan probes and restriction fragment length polymorphism (RFLP). The association study was performed using the HaploView 4.0 software. RESULTS: The allelic frequency analysis revealed that rs529825, rs800292, rs203674 and rs10671170 were significantly associated with an increased risk for AMD. The haplotypes CGG (rs3753394, rs529825 and rs800292) and GCAG (rs203674, rs1061170, rs3753396 and rs1065489) were significantly associated with AMD while the haplotypes CAA (rs3753394, rs529825 and rs800292) and TTAG (rs203674, rs1061170, rs3753396 and rs1065489) were found to be protective. Small differ-ences in allelic frequencies were found between dry and neovascular cases; however, these differences were not significant and did not distinguish one form the other. CONCLUSIONS: This study found significant association of SNPs rs529825, rs800292, rs203674 and rs1061170 in the CFH gene with susceptibility to AMD. We identified haplotypes that confer protection or increased risk of AMD but not specific genetic variants in CFH capable to distinguish the different clinical forms of AMD in this cohort. Collectively, our results confirmed that CFH represents a strong genetic risk factor for this disease in the Northern Spanish population.