Norimoto Gotoh

Genetic variants near TIMP3 and high-density lipoprotein–associated loci influence susceptibility to age-related macular degeneration

We executed a genome-wide association scan for age-related macular degeneration (AMD) in 2,157 cases and 1,150 controls. Our results validate AMD susceptibility loci near CFH (P < 10−75), ARMS2 (P < 10−59), C2/CFB (P < 10−20), C3 (P < 10−9), and CFI (P < 10−6). We compared our top findings with the Tufts/Massachusetts General Hospital genome-wide association study of advanced AMD (821 cases, 1,709 controls) and genotyped 30 promising markers in additional individuals (up to 7,749 cases and 4,625 controls). With these data, we identified a susceptibility locus near TIMP3 (overall P = 1.1 × 10−11), a metalloproteinase involved in degradation of the extracellular matrix and previously implicated in early-onset maculopathy. In addition, our data revealed strong association signals with alleles at two loci (LIPC, P = 1.3 × 10−7; CETP, P = 7.4 × 10−7) that were previously associated with high-density lipoprotein cholesterol (HDL-c) levels in blood. Consistent with the hypothesis that HDL metabolism is associated with AMD pathogenesis, we also observed association with AMD of HDL-c—associated alleles near LPL (P = 3.0 × 10−3) and ABCA1 (P = 5.6 × 10−4). Multilocus analysis including all susceptibility loci showed that 329 of 331 individuals (99%) with the highest-risk genotypes were cases, and 85% of these had advanced AMD. Our studies extend the catalog of AMD associated loci, help identify individuals at high risk of disease, and provide clues about underlying cellular pathways that should eventually lead to new therapies.

A Genome-Wide Association Analysis Identified a Novel Susceptible Locus for Pathological Myopia at 11q24.1

Myopia is one of the most common ocular disorders worldwide. Pathological myopia, also called high myopia, comprises 1% to 5% of the general population and is one of the leading causes of legal blindness in developed countries. To identify genetic determinants associated with pathological myopia in Japanese, we conducted a genome-wide association study, analyzing 411,777 SNPs with 830 cases and 1,911 general population controls in a two-stage design (297 cases and 934 controls in the first stage and 533 cases and 977 controls in the second stage). We selected 22 SNPs that showed P-values smaller than 10−4 in the first stage and tested them for association in the second stage. The meta-analysis combining the first and second stages identified an SNP, rs577948, at chromosome 11q24.1, which was associated with the disease (P = 2.22×10−7 and OR of 1.37 with 95% confidence interval: 1.21–1.54). Two genes, BLID and LOC399959, were identified within a 200-kb DNA encompassing rs577948. RT–PCR analysis demonstrated that both genes were expressed in human retinal tissue. Our results strongly suggest that the region at 11q24.1 is a novel susceptibility locus for pathological myopia in Japanese.

CFH and ARMS2 variations in age-related macular degeneration, polypoidal choroidal vasculopathy, and retinal angiomatous proliferation.

PURPOSE To seek an association in Japanese individuals between the CFH polymorphisms Y402H and I62V and the ARMS2 polymorphism A69S and age-related macular degeneration (AMD) or its three subtypes: typical (t)AMD, polypoidal choroidal vasculopathy (PCV), and retinal angiomatous proliferation (RAP). METHODS The three polymorphisms were genotyped in a case-control study of 1351 control subjects and 962 patients with AMD. RESULTS The three polymorphisms correlated with AMD (Y402H, P = 1.54 × 10(-6); I62V, P =1.94 × 10(-29); and A69S, P = 9.56 × 10(-43)). The I62V and A69S polymorphisms were associated with all three subtypes: tAMD (P = 3.74 × 10(-18) and 1.37 × 10(-35), respectively), PCV (P = 3.18 × 10(-19) and 3.96 × 10(-18), respectively), and RAP (P = 0.034 and 2.49 × 10(-18), respectively). Y402H was associated with tAMD (P = 3.00 × 10(-5)) and with PCV (P = 9.73 × 10(-5)), but no association was found with RAP, possibly because of the small sample size and the rare minor allele. The risk allele contribution of A69S was stronger for RAP than for tAMD or PCV and was stronger for tAMD than for PCV. CONCLUSIONS CFH Y402H is associated with AMD, tAMD, and PCV, whereas I62V is associated with all three subtypes. ARMS2 A69S has a strong association with all three subtypes, with the association being strongest for RAP and weakest for PCV. PCV and RAP may thus be subtypes of AMD that are genetically distinct from tAMD.

Lysyl oxidase-like 1 polymorphisms and exfoliation syndrome in the Japanese population.

PURPOSE To investigate the contribution of two single-nucleotide polymorphisms (SNPs) of the lysyl oxidase-like 1 (LOXL1) gene, recently shown to be associated with exfoliation syndrome (XFS) and exfoliation glaucoma (XFG) in the Nordic population, to the occurrence of XFS and XFG in the Japanese population. DESIGN Case-control association study. METHODS A total of 59 unrelated Japanese individuals with XFS, 27 XFG patients, and 190 population-based controls were recruited. The SNPs rs1048661 (R141L) and rs3825942 (G153D) in the LOXL1 gene were genotyped directly. Association tests were performed for the two SNPs and inferred haplotypes. RESULTS The frequency of the G allele in rs1048661, reportedly a functional risk allele in White persons, existed in only 0.8% of Japanese XFS cases, but occurred with much higher frequency in controls (46.0%) and yielded a P value of 3.0x10(-19), and the odds ratio for the T allele in rs1048661 was 99.8 (95% confidence interval, 13.8 to 722). For rs3825942, the frequency of the G allele, which is another possible risk allele in White persons with XFS, was 1.000 vs 0.857 in the controls (P=1.4x10(-5)). The most frequent haplotype in Japanese XFS patients was haplotype (T,G) (99.2%). The (G,G) haplotype, which generates the highest risk in White persons, was present in only a small percentage of Japanese XFS cases (0.8%). CONCLUSIONS The SNPs rs1048661 and rs3825942 of the LOXL1 gene seem to be highly associated with XFS in the Japanese population, but a different polymorphism of LOXL1 may cause the development of XFS in the Japanese population.

ARMS2 (LOC387715) Variants in Japanese Patients with Exudative Age-related Macular Degeneration and Polypoidal Choroidal Vasculopathy

PURPOSE To determine the characteristics of the polymorphisms in the ARMS2 gene in Japanese patients with age-related macular degeneration (AMD) and those with polypoidal choroidal vasculopathy (PCV) and in healthy controls, and also to show possible associations of the polymorphisms with the disease. DESIGN Case-control association study. METHODS Fifty-six unrelated Japanese individuals with AMD, 55 with PCV, and 77 controls were studied. The most common polymorphism in the ARMS2 gene on chromosome 10 was resequenced. Association tests were performed for inferred haplotypes. RESULTS A total of 22 polymorphisms were identified, and 13 were shared with those in White persons with AMD. The sequence of the deletion-and-insertion polymorphism, de1443ins54, a functional polymorphism causing an instability of the messenger ribonucleic acid of ARMS2 in the Japanese, did not differ from that in White persons. Among the polymorphisms seen in the White population, rs10490923 (R3H) as well as 7 other polymorphisms were not observed in the Japanese. One haplotype, which contained the T allele of the rs10490924 (A69S) and the variant of de1443ins54 polymorphism, had an odds ratio of 3.14 (P = 7.8 x 10(-6)) for AMD and 2.00 (P = .0058) for PCV. Among the 9 polymorphisms that were unique to the Japanese population, 2 had a minor allelic frequency of more than 0.05, and these 2 polymorphism were included as nonrisk haplotypes. CONCLUSIONS The de1443ins54 polymorphism is a common variant between White and Japanese populations. It is strongly associated not only with AMD but also with PCV.

Correlation between CFH Y402H and HTRA1 rs11200638 genotype to typical exudative age-related macular degeneration and polypoidal choroidal vasculopathy phenotype in the Japanese population.

Background:  Typical exudative age‐related macular degeneration (AMD) and polypoidal choroidal vasculopathy (PCV) are two of the major macular diseases found in Asians. Although genomic studies have shown a contribution by CFH and LOC387715/HTRA1 polymorphisms to the development of these two diseases, the correlation of the clinical phenotypes to these genotypes has not been determined in Asian patients.

Transcriptional Regulation of Rod Photoreceptor Homeostasis Revealed by In Vivo NRL Targetome Analysis

A stringent control of homeostasis is critical for functional maintenance and survival of neurons. In the mammalian retina, the basic motif leucine zipper transcription factor NRL determines rod versus cone photoreceptor cell fate and activates the expression of many rod-specific genes. Here, we report an integrated analysis of NRL-centered gene regulatory network by coupling chromatin immunoprecipitation followed by high-throughput sequencing (ChIP–Seq) data from Illumina and ABI platforms with global expression profiling and in vivo knockdown studies. We identified approximately 300 direct NRL target genes. Of these, 22 NRL targets are associated with human retinal dystrophies, whereas 95 mapped to regions of as yet uncloned retinal disease loci. In silico analysis of NRL ChIP–Seq peak sequences revealed an enrichment of distinct sets of transcription factor binding sites. Specifically, we discovered that genes involved in photoreceptor function include binding sites for both NRL and homeodomain protein CRX. Evaluation of 26 ChIP–Seq regions validated their enhancer functions in reporter assays. In vivo knockdown of 16 NRL target genes resulted in death or abnormal morphology of rod photoreceptors, suggesting their importance in maintaining retinal function. We also identified histone demethylase Kdm5b as a novel secondary node in NRL transcriptional hierarchy. Exon array analysis of flow-sorted photoreceptors in which Kdm5b was knocked down by shRNA indicated its role in regulating rod-expressed genes. Our studies identify candidate genes for retinal dystrophies, define cis-regulatory module(s) for photoreceptor-expressed genes and provide a framework for decoding transcriptional regulatory networks that dictate rod homeostasis.

Developing Rods Transplanted into the Degenerating Retina of Crx-Knockout Mice Exhibit Neural Activity Similar to Native Photoreceptors†‡§

Replacement of dysfunctional or dying photoreceptors offers a promising approach for retinal neurodegenerative diseases, including age‐related macular degeneration and retinitis pigmentosa. Several studies have demonstrated the integration and differentiation of developing rod photoreceptors when transplanted in wild‐type or degenerating retina; however, the physiology and function of the donor cells are not adequately defined. Here, we describe the physiological properties of developing rod photoreceptors that are tagged with green fluorescent protein (GFP) driven by the promoter of rod differentiation factor, Nrl. GFP‐tagged developing rods show Ca2 + responses and rectifier outward currents that are smaller than those observed in fully developed photoreceptors, suggesting their immature developmental state. These immature rods also exhibit hyperpolarization‐activated current (Ih) induced by the activation of hyperpolarization‐activated cyclic nucleotide‐gated (HCN) channels. When transplanted into the subretinal space of wild‐type or retinal degeneration mice, GFP‐tagged developing rods can integrate into the photoreceptor outer nuclear layer in wild‐type mouse retina and exhibit Ca2 + responses and membrane current comparable to native rod photoreceptors. A proportion of grafted rods develop rhodopsin‐positive outer segment‐like structures within 2 weeks after transplantation into the retina of Crx‐knockout mice and produce rectifier outward current and Ih upon membrane depolarization and hyperpolarization. GFP‐positive rods derived from induced pluripotent stem (iPS) cells also display similar membrane current Ih as native developing rod photoreceptors, express rod‐specific phototransduction genes, and HCN‐1 channels. We conclude that Nrl‐promoter‐driven GFP‐tagged donor photoreceptors exhibit physiological characteristics of rods and that iPS cell‐derived rods in vitro may provide a renewable source for cell‐replacement therapy. STEM Cells 2013;31:1149–1159

Macular complications on the border of an inferior staphyloma associated with tilted disc syndrome.

Purpose: To describe the clinical characteristics of macular complications on the border of an inferior staphyloma associated with tilted disk syndrome. Methods: We reviewed retrospectively the medical records of 32 consecutive eyes of 20 patients with tilted disk syndrome and an inferior staphyloma lying across the macula. Results: In 21 (66%) eyes, fluorescein angiography showed window defects on the border of the staphyloma, where the early phase of indocyanine green angiography showed hypofluorescence due to atrophy of the choriocapillaris. On the late phase of indocyanine green angiography, 19 eyes (59%) showed hyperfluorescence along the border of the staphyloma, which often extended beyond the area of the window defect. Of the 32 eyes, 25 (78%) had macular complications: polypoidal choroidal vasculopathy in 7 (22%), classic choroidal neovascularization in 1 (3%), focal serous retinal detachment without polypoidal choroidal vasculopathy or choroidal neovascularization in 13 (41%), and atrophy of the retinal pigment epithelium alone in 4 (13%). Visual acuity in eyes with polypoidal choroidal vasculopathy or choroidal neovascularization was significantly worse than that in eyes with other complications (P < 0.001). Conclusions: Eyes with tilted disk syndrome often have macular complications on the border of the inferior staphyloma, which can cause severe visual loss.

Alterations of retinal pigment epithelium in central serous chorioretinopathy

Background:  To examine with en face optical coherence tomography (OCT) the alterations of retinal pigment epithelium (RPE) in central serous chorioretinopathy (CSC) and their role in the pathophysiology of CSC.