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Full-Text Articles in Ophthalmology

Raav2/5 Gene-Targeting To Rods: Dose-Dependent Efficiency And Complications Associated With Different Promoters, William Beltran, Sanford L. Boye, Shannon E. Boye, Vince A. Chiodo, Alfred S. Lewin, William W. Hauswirth, Gustavo D. Aguirre Feb 2016

Raav2/5 Gene-Targeting To Rods: Dose-Dependent Efficiency And Complications Associated With Different Promoters, William Beltran, Sanford L. Boye, Shannon E. Boye, Vince A. Chiodo, Alfred S. Lewin, William W. Hauswirth, Gustavo D. Aguirre

Gustavo D. Aguirre, VMD, PhD

A prerequisite for using corrective gene therapy to treat humans with inherited retinal degenerative diseases that primarily affect rods is to develop viral vectors that target specifically this population of photoreceptors. The delivery of a viral vector with photoreceptor tropism coupled with a rod-specific promoter is likely to be the safest and most efficient approach to target expression of the therapeutic gene to rods. Three promoters that included a fragment of the proximal mouse opsin promoter (mOP), the human G-protein-coupled receptor protein kinase 1 promoter (hGRK1), or the cytomegalovirus immediate early enhancer combined with the chicken β actin proximal promoter …


Exonic Sine Insertion In Stk38l Causes Canine Early Retinal Degeneration (Erd), Orly Goldstein, Anna V. Kukekova, Gustavo D. Aguirre, Gregory M. Acland Feb 2016

Exonic Sine Insertion In Stk38l Causes Canine Early Retinal Degeneration (Erd), Orly Goldstein, Anna V. Kukekova, Gustavo D. Aguirre, Gregory M. Acland

Gustavo D. Aguirre, VMD, PhD

Fine mapping followed by candidate gene analysis of erd — a canine hereditary retinal degeneration characterized by aberrant photoreceptor development — established that the disease cosegregates with a SINE insertion in exon 4 of the canine STK38L/NDR2 gene. The mutation removes exon 4 from STK38L transcripts and is predicted to remove much of the N terminus from the translated protein, including binding sites for S100B and Mob proteins, part of the protein kinase domain, and a Thr-75 residue critical for autophosphorylation. Although known to have roles in neuronal cell function, the STK38L pathway has not previously been implicated in normal …


Identification Of Genetic Variation And Haplotype Structure Of The Canine Abca4 Gene For Retinal Disease Association Studies, Barbara Zangerl, Sarah J. Lindauer, Gregory M. Acland, Gustavo D. Aguirre Feb 2016

Identification Of Genetic Variation And Haplotype Structure Of The Canine Abca4 Gene For Retinal Disease Association Studies, Barbara Zangerl, Sarah J. Lindauer, Gregory M. Acland, Gustavo D. Aguirre

Gustavo D. Aguirre, VMD, PhD

Over 200 mutations in the retina specific member of the ATP-binding cassette transporter superfamily (ABCA4) have been associated with a diverse group of human retinal diseases. The disease mechanisms, and genotype–phenotype associations, nonetheless, remain elusive in many cases. As orthologous genes are commonly mutated in canine models of human blinding disorders, canine ABCA4 appears to be an ideal candidate gene to identify and study sequence changes in dogs affected by various forms of inherited retinal degeneration. However, the size of the gene and lack of haplotype assignment significantly limit targeted association and/or linkage approaches. This study assessed the naturally observed …


Modeling The Structural Consequences Of Best1 Missense Mutations, Karina E. Guziewicz, Gustavo D. Aguirre, Barbara Zangerl Feb 2016

Modeling The Structural Consequences Of Best1 Missense Mutations, Karina E. Guziewicz, Gustavo D. Aguirre, Barbara Zangerl

Gustavo D. Aguirre, VMD, PhD

Mutations in the bestrophin-1 gene (BEST1) are an important cause of inherited retinal disorders. Hitherto, over 100 unique allelic variants have been linked to the human BEST1 (hBEST1), and associated with disease phenotypes, broadly termed as bestrophinopathies. A spontaneous animal model recapitulating BEST1-related phenotypes, canine multifocal retinopathy (cmr), is caused by mutations in the canine gene ortholog (cBEST1). We have recently characterized molecular consequences of cmr, demonstrating defective protein trafficking as a result of G161D (cmr2) mutation. To further investigate the pathological effects of BEST1 missense mutations, canine and human peptide fragments derived from the protein sequence have been studied …


Identical Mutation In A Novel Retinal Gene Causes Progressive Rod-Cone Degeneration In Dogs And Retinitis Pigmentosa In Humans, Barbara Zangerl, Orly Goldstein, Alisdair R. Philip, Sarah J. P Lindauer, Susan E. Pearce-Kelling, Roberts F. Mullins, Alexander S. Graphodatsky, Daniel Ripoll, Jeanette S. Felix, Edwin M. Stone, Gregory M. Acland, Gustavo D. Aguirre Feb 2016

Identical Mutation In A Novel Retinal Gene Causes Progressive Rod-Cone Degeneration In Dogs And Retinitis Pigmentosa In Humans, Barbara Zangerl, Orly Goldstein, Alisdair R. Philip, Sarah J. P Lindauer, Susan E. Pearce-Kelling, Roberts F. Mullins, Alexander S. Graphodatsky, Daniel Ripoll, Jeanette S. Felix, Edwin M. Stone, Gregory M. Acland, Gustavo D. Aguirre

Gustavo D. Aguirre, VMD, PhD

Progressive rod–cone degeneration (prcd) is a late-onset, autosomal recessive photoreceptor degeneration of dogs and a homolog for some forms of human retinitis pigmentosa (RP). Previously, the disease-relevant interval was reduced to a 106-kb region on CFA9, and a common phenotype-specific haplotype was identified in all affected dogs from several different breeds and breed varieties. Screening of a canine retinal EST library identified partial cDNAs for novel candidate genes in the disease-relevant interval. The complete cDNA of one of these, PRCD, was cloned in dog, human, and mouse. The gene codes for a 54-amino-acid (aa) protein in dog and human and …


Canine Rd3 Mutation Establishes Rod-Cone Dysplasia Type 2 (Rcd2) As Ortholog Of Human And Murine Rd3, Anna V. Kukekova, Orly Goldstein, Jennifer L. Johnson, Malcolm A. Richardson, Susan E. Pearce-Kelling, Anand Swaroop, James S. Friedman, Gustavo D. Aguirre, Gregory M. Acland Feb 2016

Canine Rd3 Mutation Establishes Rod-Cone Dysplasia Type 2 (Rcd2) As Ortholog Of Human And Murine Rd3, Anna V. Kukekova, Orly Goldstein, Jennifer L. Johnson, Malcolm A. Richardson, Susan E. Pearce-Kelling, Anand Swaroop, James S. Friedman, Gustavo D. Aguirre, Gregory M. Acland

Gustavo D. Aguirre, VMD, PhD

Rod-cone dysplasia type 2 (rcd2) is an autosomal recessive disorder that segregates in collie dogs. Linkage disequilibrium and meiotic linkage mapping were combined to take advantage of population structure within this breed and to fine map rcd2 to a 230-kb candidate region that included the gene C1orf36 responsible for human and murine rd3, and within which all affected dogs were homozygous for one haplotype. In one of three identified canine retinal RD3 splice variants, an insertion was found that cosegregates with rcd2 and is predicted to alter the last 61 codons of the normal open reading frame and further extend …


Comparative Genomic Mapping Of Uncharacterized Canine Retinal Ests To Identify Novel Candidate Genes For Hereditary Retinal Disorders, Barbara Zangerl, Jennifer L. Johnson, Jarek Pillardy, Qi Sun, Catherine André, Francis Galibert, Gregory M. Acland, Gustavo D. Aguirre Feb 2016

Comparative Genomic Mapping Of Uncharacterized Canine Retinal Ests To Identify Novel Candidate Genes For Hereditary Retinal Disorders, Barbara Zangerl, Jennifer L. Johnson, Jarek Pillardy, Qi Sun, Catherine André, Francis Galibert, Gregory M. Acland, Gustavo D. Aguirre

Gustavo D. Aguirre, VMD, PhD

Purpose: To identify the genomic location of previously uncharacterized canine retina-expressed expressed sequence tags (ESTs), and thus identify potential candidate genes for heritable retinal disorders. Methods: A set of over 500 retinal canine ESTs were mapped onto the canine genome using the RHDF5000–2 radiation hybrid (RH) panel, and the resulting map positions were compared to their respective localization in the CanFam2 assembly of the canine genome sequence. Results: Unique map positions could be assigned for 99% of the mapped clones, of which only 29% showed significant homology to known RefSeq sequences. A comparison between RH map and sequence assembly indicated …


Clinical Light Exposure, Photoreceptor Degeneration, And Ap-1 Activation: A Cell Death Or Cell Survival Signal In The Rhodopsin Mutant Retina?, Danian Gu, William Beltran, Zexiao Li, Gregory M. Acland, Gustavo D. Aguirre Feb 2016

Clinical Light Exposure, Photoreceptor Degeneration, And Ap-1 Activation: A Cell Death Or Cell Survival Signal In The Rhodopsin Mutant Retina?, Danian Gu, William Beltran, Zexiao Li, Gregory M. Acland, Gustavo D. Aguirre

Gustavo D. Aguirre, VMD, PhD

PURPOSE. The T4R RHO mutant dog retina shows retinal degeneration with exposures to light comparable to those used in clinical eye examinations of patients. To define the molecular mechanisms of the degeneration, AP-1 DNA-binding activity, composition, posttranslational modification of the protein complex, and modulation of ERK/MAPK signaling pathways were examined in light-exposed mutant retinas. METHODS. Dark-adapted retinas were exposed to short-duration light flashes from a retinal camera used clinically for retinal photography and were collected at different time points after exposure. Electrophoretic mobility shift assay (EMSA), supershift EMSA, Western blot analysis, and immunocytochemistry were used to examine AP-1 signaling. RESULTS. …


Bestrophin Gene Mutations Cause Canine Multifocal Retinopathy: A Novel Animal Model For Best Disease, Karina E. Guziewicz, Barbara Zangerl, Sarah J. Lindauer, Robert F. Mullins, Lynne S. Sandmeyer, Bruce H. Grahn, Edwin M. Stone, Gregory M. Acland, Gustavo D. Aguirre Feb 2016

Bestrophin Gene Mutations Cause Canine Multifocal Retinopathy: A Novel Animal Model For Best Disease, Karina E. Guziewicz, Barbara Zangerl, Sarah J. Lindauer, Robert F. Mullins, Lynne S. Sandmeyer, Bruce H. Grahn, Edwin M. Stone, Gregory M. Acland, Gustavo D. Aguirre

Gustavo D. Aguirre, VMD, PhD

PURPOSE. Canine multifocal retinopathy (cmr) is an autosomal recessive disorder of multiple dog breeds. The disease shares a number of clinical and pathologic similarities with Best macular dystrophy (BMD), and cmr is proposed as a new large animal model for Best disease. METHODS. cmr was characterized by ophthalmoscopy and histopathology and compared with BMD-affected patients. BEST1 (alias VMD2), the bestrophin gene causally associated with BMD, was evaluated in the dog. Canine ortholog cDNA sequence was cloned and verified using RPE/choroid 5′- and 3′-RACE. Expression of the canine gene transcripts and protein was analyzed by Northern and Western blotting and immunocytochemistry. …


Development And Validation Of A Canine-Specific Profiling Array To Examine Expression Of Pro-Apoptotic And Pro-Survival Genes In Retinal Degenerative Diseases, Sem Genini, William Beltran, Gustavo D. Aguirre Feb 2016

Development And Validation Of A Canine-Specific Profiling Array To Examine Expression Of Pro-Apoptotic And Pro-Survival Genes In Retinal Degenerative Diseases, Sem Genini, William Beltran, Gustavo D. Aguirre

Gustavo D. Aguirre, VMD, PhD

We developed an expression profiling array to examine pro-apoptotic and pro-survival genes in dog retinal degeneration models. Gene-specific canine TaqMan assays were developed and included in a custom real-time quantitative reverse transcription-PCR (qRT-PCR) array. Of the 96 selected genes, 93 belonged to known relevant pro-apoptotic and pro-survival pathways, and/or were positive controls expressed in retina, while three were housekeeping genes. Ingenuity Pathway Analysis (IPA) showed that the selected genes belonged to expected biological functions (cell death, cell-mediated immune response, cellular development, function, and maintenance) and pathways (death receptor signaling, apoptosis, TNFR1 signaling, and induction of apoptosis by HIV1). Validation of …


Steroids Do Not Prevent Photoreceptor Degeneration In The Light-Exposed T4r Rhodopsin Mutant Dog Retina Irrespective Of Ap-1 Inhibition, Danian Gu, William Beltran, Sue Pearce-Kelling, Zexiao Li, Gregory M. Acland, Gustavo D. Aguirre Feb 2016

Steroids Do Not Prevent Photoreceptor Degeneration In The Light-Exposed T4r Rhodopsin Mutant Dog Retina Irrespective Of Ap-1 Inhibition, Danian Gu, William Beltran, Sue Pearce-Kelling, Zexiao Li, Gregory M. Acland, Gustavo D. Aguirre

Gustavo D. Aguirre, VMD, PhD

PURPOSE. AP-1 has been proposed as a key intermediate linking exposure to light and photoreceptor cell death in rodent light-damage models. Inhibition of AP-1 associated with steroid administration also prevents light damage. In this study the role of steroids in inhibiting AP-1 activation and/or in preventing photoreceptor degeneration was examined in the rhodopsin mutant dog model. METHODS. The dogs were dark adapted overnight, eyes dilated with mydriatics; the right eye was light occluded and the fundus of the left eye photographed (∼15–17 overlapping frames) with a fundus camera. For biochemical studies, the dogs remained in the dark for 1 to …


Linkage Disequilibrium Mapping In Domestic Dog Breeds Narrows The Progressive Rod-Cone Degeneration Interval And Identifies Ancestral Disease-Transmitting Chromosome, Orly Goldstein, Barbara Zangerl, Sue Pearce-Kelling, Duska J. Sidjanin, James W. Kijas, Jeanette Felix, Gregory M. Acland, Gustavo D. Aguirre Feb 2016

Linkage Disequilibrium Mapping In Domestic Dog Breeds Narrows The Progressive Rod-Cone Degeneration Interval And Identifies Ancestral Disease-Transmitting Chromosome, Orly Goldstein, Barbara Zangerl, Sue Pearce-Kelling, Duska J. Sidjanin, James W. Kijas, Jeanette Felix, Gregory M. Acland, Gustavo D. Aguirre

Gustavo D. Aguirre, VMD, PhD

Canine progressive rod–cone degeneration (prcd) is a retinal disease previously mapped to a broad, gene-rich centromeric region of canine chromosome 9. As allelic disorders are present in multiple breeds, we used linkage disequilibrium (LD) to narrow the ∼6.4-Mb interval candidate region. Multiple dog breeds, each representing genetically isolated populations, were typed for SNPs and other polymorphisms identified from BACs. The candidate region was initially localized to a 1.5-Mb zero recombination interval between growth factor receptor-bound protein 2 (GRB2) and SEC14-like 1 (SEC14L). A fine-scale haplotype of the region was developed, which reduced the LD interval to 106 kb and identified …


Long-Term Restoration Of Rod And Cone Vision By Single Dose Raav-Mediated Gene Transfer To The Retina In A Canine Model Of Childhood Blindness, Gregory M. Acland, Gustavo D. Aguirre, Jean Bennett, Tomas S. Aleman, Artur V. Cideciyan, Jeannette Bennicelli, Nadine S. Dejneka, Susan E. Pearce-Kelling, Albert M. Maguire, Krzysztof Palczewski, William W. Hauswirth, Samuel G. Jacobson Feb 2016

Long-Term Restoration Of Rod And Cone Vision By Single Dose Raav-Mediated Gene Transfer To The Retina In A Canine Model Of Childhood Blindness, Gregory M. Acland, Gustavo D. Aguirre, Jean Bennett, Tomas S. Aleman, Artur V. Cideciyan, Jeannette Bennicelli, Nadine S. Dejneka, Susan E. Pearce-Kelling, Albert M. Maguire, Krzysztof Palczewski, William W. Hauswirth, Samuel G. Jacobson

Gustavo D. Aguirre, VMD, PhD

The short- and long-term effects of gene therapy using AAV-mediated RPE65 transfer to canine retinal pigment epithelium were investigated in dogs affected with disease caused by RPE65 deficiency. Results with AAV 2/2, 2/1, and 2/5 vector pseudotypes, human or canine RPE65 cDNA, and constitutive or tissue-specific promoters were similar. Subretinally administered vectors restored retinal function in 23 of 26 eyes, but intravitreal injections consistently did not. Photoreceptoral and postreceptoral function in both rod and cone systems improved with therapy. In dogs followed electroretinographically for 3 years, responses remained stable. Biochemical analysis of retinal retinoids indicates that mutant dogs have no …


Genetic And Phenotypic Variations Of Inherited Retinal Diseases In Dogs: The Power Of Within- And Across-Breed Studies, Keiko Miyadera, Gregory M. Acland, Gustavo D. Aguirre Feb 2016

Genetic And Phenotypic Variations Of Inherited Retinal Diseases In Dogs: The Power Of Within- And Across-Breed Studies, Keiko Miyadera, Gregory M. Acland, Gustavo D. Aguirre

Gustavo D. Aguirre, VMD, PhD

Considerable clinical and molecular variations have been known in retinal blinding diseases in man and also in dogs. Different forms of retinal diseases occur in specific breed(s) caused by mutations segregating within each isolated breeding population. While molecular studies to find genes and mutations underlying retinal diseases in dogs have benefited largely from the phenotypic and genetic uniformity within a breed, within- and across-breed variations have often played a key role in elucidating the molecular basis. The increasing knowledge of phenotypic, allelic, and genetic heterogeneities in canine retinal degeneration has shown that the overall picture is rather more complicated than …


Cloning And Characterization Of Canine Pax6 And Evaluation As A Candidate Gene In A Canine Model Of Aniridia, Linda S. Hunter, Duska J. Sidjanin, Manuel Villagrasa Hijar, Jennifer L. Johnson, Ewen Kirkness, Gregory M. Acland, Gustavo D. Aguirre Feb 2016

Cloning And Characterization Of Canine Pax6 And Evaluation As A Candidate Gene In A Canine Model Of Aniridia, Linda S. Hunter, Duska J. Sidjanin, Manuel Villagrasa Hijar, Jennifer L. Johnson, Ewen Kirkness, Gregory M. Acland, Gustavo D. Aguirre

Gustavo D. Aguirre, VMD, PhD

Purpose: Mutations in PAX6 cause human aniridia. The small eye (sey) mouse represents an animal model for aniridia. However, no large animal model currently exists. We cloned and characterized canine PAX6, and evaluated PAX6 for causal associations with inherited aniridia in dogs. Methods: Canine PAX6 was cloned from a canine retinal cDNA library using primers designed from human and mouse PAX6 consensus sequences. An RH3000 radiation hybrid panel was used to localize PAX6 within the canine genome. Genomic DNA was extracted from whole blood of dogs with inherited aniridia, and association testing was performed using markers on CFA18. Fourteen PAX6 …


Cloning Of Canine Galactokinase (Galk1) And Evaluation As A Candidate Gene For Hereditary Cataracts In Labrador Retrievers, Duska J. Sidjanin, John L. Mcelwee, Brian Miller, Gustavo D. Aguirre Feb 2016

Cloning Of Canine Galactokinase (Galk1) And Evaluation As A Candidate Gene For Hereditary Cataracts In Labrador Retrievers, Duska J. Sidjanin, John L. Mcelwee, Brian Miller, Gustavo D. Aguirre

Gustavo D. Aguirre, VMD, PhD

We identified a pedigree of Labrador retrievers (LR) that develop hereditary cataracts between 6 and 18 months of age. In humans, galactokinase deficiency is an autosomal recessive disorder characterized by juvenile onset of cataracts.1 In order to evaluate GALK1 as a candidate gene, we cloned and sequenced the canine GALK1 gene and tested a single nucleotide polymorphism (SNP) in the gene for segregation with cataracts in the LR pedigree.


Age-Dependent Disease Expression Determines Remodeling Of The Retinal Mosaic In Carriers Of Rpgr Exon Orfn15 Mutations, William Beltran, Gregory M. Acland, Gustavo D. Aguirre Feb 2016

Age-Dependent Disease Expression Determines Remodeling Of The Retinal Mosaic In Carriers Of Rpgr Exon Orfn15 Mutations, William Beltran, Gregory M. Acland, Gustavo D. Aguirre

Gustavo D. Aguirre, VMD, PhD

PURPOSE. To characterize the retinal histopathology in carriers of X-linked progressive retinal atrophy (XLPRA1 and XLPRA2), two canine models of X-linked retinitis pigmentosa caused, respectively, by a stop and a frameshift mutation in RPGRORF15. METHODS. Retinas of XLPRA2 and XLPRA1 carriers of different ages were processed for morphologic evaluation, TUNEL assay, and immunohistochemistry. Cell-specific markers were used to examine retinal remodeling events. RESULTS. A mosaic pattern composed of patches of diseased and normal retina was first detected in XLPRA2 carriers at 4.9 weeks of age. A peak of photoreceptor cell death led to focal rod loss; however, in these patches …


Blinded By The Light: Retinal Phototoxicity In The Context Of Safety Studies, Maria Cristina De Vera Mudry, Sven Kronenberg, Shun-Ichiro Komatsu, Gustavo D. Aguirre Feb 2016

Blinded By The Light: Retinal Phototoxicity In The Context Of Safety Studies, Maria Cristina De Vera Mudry, Sven Kronenberg, Shun-Ichiro Komatsu, Gustavo D. Aguirre

Gustavo D. Aguirre, VMD, PhD

No abstract provided.


Canine Multifocal Retinopathy In The Australian Shepherd: A Case Report, Ingo Hoffmann, Karina E. Guziewicz, Barbara Zangerl, Gustavo D. Aguirre, Christian Y. Mardin Feb 2016

Canine Multifocal Retinopathy In The Australian Shepherd: A Case Report, Ingo Hoffmann, Karina E. Guziewicz, Barbara Zangerl, Gustavo D. Aguirre, Christian Y. Mardin

Gustavo D. Aguirre, VMD, PhD

A 1-year-old Australian Shepherd (AS) was presented for a routine hereditary eye examination. During the examination multiple raised, brown to orange lesions were noted in the fundus, which could not be attributed to a known retinal disease in this breed. As they clinically most closely resembled canine multifocal retinopathy (cmr) and no indication of an acquired condition was found, genetic tests for BEST1 gene mutations were performed. These showed the dog to be homozygous for the cmr1 (C73T/R25X) gene defect. Furthermore, ultrasound (US), electroretinography (ERG), and optical coherence tomography were performed, confirming changes typical for cmr. Subsequently, the AS pedigree …


A Naturally Occurring Mutation Of The Opsin Gene (T4r) In Dogs Affects Glycosylation And Stability Of The G Protein-Coupled Receptor, Li Zhu, Geeng-Fu Jang, Beata Jastrzebska, Slawomir Filipek, Susan E. Pearce-Kelling, Gustavo D. Aguirre, Ronald E. Stenkamp, Gregory M. Acland, Krzysztof Palczewski Feb 2016

A Naturally Occurring Mutation Of The Opsin Gene (T4r) In Dogs Affects Glycosylation And Stability Of The G Protein-Coupled Receptor, Li Zhu, Geeng-Fu Jang, Beata Jastrzebska, Slawomir Filipek, Susan E. Pearce-Kelling, Gustavo D. Aguirre, Ronald E. Stenkamp, Gregory M. Acland, Krzysztof Palczewski

Gustavo D. Aguirre, VMD, PhD

Rho (rhodopsin; opsin plus 11-cis-retinal) is a prototypical G protein-coupled receptor responsible for the capture of a photon in retinal photoreceptor cells. A large number of mutations in the opsin gene associated with autosomal dominant retinitis pigmentosa have been identified. The naturally occurring T4R opsin mutation in the English mastiff dog leads to a progressive retinal degeneration that closely resembles human retinitis pigmentosa caused by the T4K mutation in the opsin gene. Using genetic approaches and biochemical assays, we explored the properties of the T4R mutant protein. Employing immunoaffinity-purified Rho from affected RHOT4R/T4R dog retina, we found …


Rpgrip1 And Cone-Rod Dystrophy In Dogs, Tatyana N. Kuznetsova, Barbara Zangerl, Gustavo D. Aguirre Feb 2016

Rpgrip1 And Cone-Rod Dystrophy In Dogs, Tatyana N. Kuznetsova, Barbara Zangerl, Gustavo D. Aguirre

Gustavo D. Aguirre, VMD, PhD

Cone–rod dystrophies (crd) represent a group of progressive inherited blinding diseases characterized by primary dysfunction and loss of cone photoreceptors accompanying or preceding rod death. Recessive crd type 1 was described in dogs associated with an RPGRIP1 exon 2 mutation, but with lack of complete concordance between genotype and phenotype. This review highlights role of the RPGRIP1, a component of complex protein networks, and its function in the primary cilium, and discusses the potential mechanisms of genotype–phenotype discordance observed in dogs with the RPGRIP1 mutation.


Transcriptional Regulatory Network Analysis During Epithelial-Mesenchymal Transformation Of Retinal Pigment Epithelium., Craig H Pratt, Rajanikanth Vadigepalli, Praveen Chakravarthula, Gregory E Gonye, Nancy J Philp, Gerald B Grunwald May 2012

Transcriptional Regulatory Network Analysis During Epithelial-Mesenchymal Transformation Of Retinal Pigment Epithelium., Craig H Pratt, Rajanikanth Vadigepalli, Praveen Chakravarthula, Gregory E Gonye, Nancy J Philp, Gerald B Grunwald

Rajanikanth Vadigepalli

PURPOSE: Phenotypic transformation of retinal pigment epithelial (RPE) cells contributes to the onset and progression of ocular proliferative disorders such as proliferative vitreoretinopathy (PVR). The formation of epiretinal membranes in PVR may involve an epithelial-mesenchymal transformation (EMT) of RPE cells as part of an aberrant wound healing response. While the underlying mechanism remains unclear, this likely involves changes in RPE cell gene expression under the control of specific transcription factors (TFs). Thus, the purpose of the present study was to identify TFs that may play a role in this process. METHODS: Regulatory regions of genes that are differentially regulated during …


The Pattern And Frequency Of T(14;18) Translocation And Immunophenotype In Asian Follicular Lymphoma, Mary Anne Tan Jin Ai Jan 2004

The Pattern And Frequency Of T(14;18) Translocation And Immunophenotype In Asian Follicular Lymphoma, Mary Anne Tan Jin Ai

Mary Anne Tan Jin Ai

Aims: Follicular lymphoma is frequently associated with t(14;18)(q32;q21) translocation. This study was undertaken to determine the pattern of Bcl-2, CD10 and Bcl-6 expression in relation to t(14;18) translocation in follicular lymphoma from a cohort of a multi-ethnic Asian population. Methods and results: Sixty-two cases of follicular lymphoma were retrieved for immunohistochemistry, and t(14;18) translocation analysis by polymerase chain reaction and fluorescent in-situ hybridization techniques. Bcl-2 expression was present in 74% of the cases. CD10 expression was also relatively low (61%), with decreasing frequency of expression in high-grade tumours. Bcl-6 protein was expressed in most of the tumours (88%) regardless of …


Apolipoprotein E Genotyping In The Malay, Chinese And Indian Ethnic Groups In Malaysia - A Study On The Distribution Of The Different Apoe Alleles And Genotypes, Mary Anne Tan Jin Ai Jan 2004

Apolipoprotein E Genotyping In The Malay, Chinese And Indian Ethnic Groups In Malaysia - A Study On The Distribution Of The Different Apoe Alleles And Genotypes, Mary Anne Tan Jin Ai

Mary Anne Tan Jin Ai

Background: Apolipoprotein E (apoE) is encoded by a polymorphic gene located on chromosome 19. The three common apoE alleles are epsilon2, epsilon3 and epsilon4. We studied the frequencies of the apoE alleles and genotypes in the three ethnic groups-Malay, Chinese and Indian-in Malaysia using DNA amplification followed by agarose gel electrophoresis. Methods: EDTA blood was collected and DNA was extracted using proteinase K-SDS digestion and purified by phenol-chloroform extraction. The apoE gene sequence was amplified using the PCR and apoE genotyping was performed by restriction enzyme digestion with HhaI. Results: Genotyping of the apoE gene produces six genotypes-E2/E2, E2/E3, E3/E3, …


Population Genetic-Study Among The Orang-Asli (Semai-Senoi) Of Malaysia - Malayan Aborigines, Mary Anne Tan Jin Ai Jan 1995

Population Genetic-Study Among The Orang-Asli (Semai-Senoi) Of Malaysia - Malayan Aborigines, Mary Anne Tan Jin Ai

Mary Anne Tan Jin Ai

A population genetic study was undertaken to provide gene frequency data on the additional blood genetic markers in the Semai and to estimate the genetic relations between the Semai and their neighboring and linguistically related populations by genetic distance and principal components analyses. Altogether 10 poly morphic and 7 monomorphic blood genetic markers (plasma proteins and red cell enzymes) were studied in a group of 349 Senoi Semai from 11. aboriginal settlements (villages) in the Pahang State of western Malaysia, Both the red cell glucosed-phosphate dehydrogenase (G6PD) and 6-phosphogluconate dehydrogenase (PGD) loci reveal the presence of polymorphic frequencies of a …


Modulation Of Mhc Expression On Human Endothelial-Cells By Sera From Patients With Systemic Lupus-Erythematosus, Mary Anne Tan Jin Ai Dec 1992

Modulation Of Mhc Expression On Human Endothelial-Cells By Sera From Patients With Systemic Lupus-Erythematosus, Mary Anne Tan Jin Ai

Mary Anne Tan Jin Ai

Major histocompatibility complex (MHC) antigen expression on cells is a prerequisite for immune interaction with activated T-cells. This study examined the ability of sera from patients with systemic lupus erythematosus (SLE) to modulate MHC expression on vascular endothelial cells. SLE sera were able to selectively upregulate MHC class I antigen expression on cultured human umbilical venous endothelial (HUVE) cells, without concomitant induction of MHC class II antigen. The stimulation index (SI) for MHC class I expression produced by SLE sera (1.21 ± 0.23) was significantly higher than those for normal controls (1.01 ± 0.10) (P < 0.0001) and non-SLE patients (1.12 ± 0.14) (P < 0.05). Additionally, active SLE patients had higher mean SI than inactive patients (P < 0.001). Preincubation of SLE sera with Protein A-Sepharose beads conjugated with antibodies against tumor necrosis factor-α and interferon-α was able to significantly reduce their ability to upregulate class I MHC expression by HUVE cells, indicating that these cytokines were responsible for the modulatory effect. This could be an important mechanism for the immune-mediated vascular injury seen in SLE.