Leber Congenital Amaurosis and Other Autosomal

Total Page:16

File Type:pdf, Size:1020Kb

Leber Congenital Amaurosis and Other Autosomal Leber Congenital Amaurosis and other autosomal recessive retinal dystrophies: A clinical and molecular genetic study Moorfields Eye Hospital Institute of Ophthalmology University College London Mr Phillip Moradi BSc MBChB FRCOphth Supervisors: Professor AT Moore, Professor AR Webster MD thesis to be submitted to the University of London I, Phillip Moradi, confirm that the work presented in this thesis is my own. Information from other sources have been referenced appropriately and indicated clearly. 1 Abstract Leber congenital amaurosis (LCA) and the early onset retinal dystrophies (EORD) are a spectrum of autosomal recessively inherited genetic conditions affecting children who have visual impairment starting under the age of five years. There are currently 19 known genes that account for approximately two thirds of cases. Only two of these 19 genes (IMPDH1 and CRX; not studied in this project) have been found to cause autosomal dominant LCA. This genetic heterogeneity makes the identification of these causative genes expensive and time consuming. Phenotype-genotype correlations are therefore important in directing efforts to determine the molecular cause of disease. The aims of this research project were to recruit and clinically characterise a large panel of LCA and EORD patients and to identify the underlying genetic cause of autosomal recessive disease. Patients were recruited from Moorfields Eye Hospital and Great Ormond Street Hospital. A full clinical examination was carried out. DNA samples were analysed using the Asper Ophthalmics LCA microarray chip and by direct sequencing. Large families, with several affected members, were examined using the Affymetrix gene chip arrays for regions of homozygosity and candidate gene sequencing was performed. DNA samples from 158 patients were obtained and 117 patients were examined clinically. A definitive molecular diagnosis was obtained for 26% of patients. Of the cohort of 158 patients with one or two mutated alleles identified and genotyped: RPE65 accounts for 1% of this cohort, 6% are due to mutations in CRB1, 15% are due to RDH12 mutations and 11% are due to mutations in CEP290. Two families were identified with novel CRALBP mutations. The genotype yield from the period of this research, August 2006- August 2 2008, is lower than that expected with newer technologies in 2014; such as next generation sequencing (NGS) or whole exome sequencing. Useful prognostic information gained will help future patients with these disorders. Patients with a molecular diagnosis may be eligible for clinical trials of gene replacement therapy. 3 Contents Abstract ............................................................................................................................... 2 Contents .............................................................................................................................. 5 1 Introduction .................................................................................................................... 17 1.1 History ......................................................................................................................... 18 1.2 Prevalence and incidence ............................................................................................ 20 1.3 Clinical spectrum ........................................................................................................ 20 1.4 Differential diagnosis .................................................................................................. 21 1.4.1 Clinically similar non-syndromic eye diseases ........................................................ 21 1.4.2 Clinically overlapping syndromic eye diseases ....................................................... 22 1.5 Molecular genetics of LCA and EORD ...................................................................... 24 1.5.1(a) Phototransduction and GUCY2D ......................................................................... 29 1.5.1(b) GUCY2D ............................................................................................................. 31 1.5.2 GUCY2D Genotype-phenotype correlations ............................................................ 33 1.6 The visual cycle and the LCA genes involved (RPE65, LRAT, RDH12) ................... 34 1.6.1 RPE65 ...................................................................................................................... 35 1.6.2a Genotype-phenotype correlations in RPE65 .......................................................... 37 1.6.2b Animal models of RPE65 and RPE65 gene therapy .............................................. 38 1.6.3 LRAT ........................................................................................................................ 39 1.6.4 Genotype-phenotype correlations for LRAT ............................................................ 40 1.6.5 RDH12 ..................................................................................................................... 40 1.6.6 Genotype-phenotype correlations for RDH12 ......................................................... 43 4 1.7 Photoreceptor development and structure (CRX, CRB1) ............................................ 44 1.7.1 CRX .......................................................................................................................... 44 1.7.2 Genotype-phenotype correlations for CRX .............................................................. 46 1.7.3 CRB1 ........................................................................................................................ 46 1.7.4 Genotype-phenotype correlations for CRB1 ............................................................ 48 1.8 Ciliopathies and LCA ................................................................................................. 48 1.8.1 TULP1 ...................................................................................................................... 49 1.8.2 Genotype-phenotype correlations for TULP1 .......................................................... 50 1.8.3 RPGR-Interacting Protein 1 ..................................................................................... 51 1.8.4 Genotype-phenotype correlations for RPGRIP1 ..................................................... 53 1.8.5 Centrosomal protein 290 (CEP290) ......................................................................... 53 1.8.6 Genotype-phenotype correlations ............................................................................ 57 1.8.7 Lebercilin LCA5 ....................................................................................................... 58 1.8.8 Genotype-phenotype correlations for LCA5 ............................................................ 59 1.9 Other LCA disease mechanisms ................................................................................. 61 1.9.1 AIPL1 ....................................................................................................................... 61 1.9.2 Genotype-phenotype correlations for AIPL1 ........................................................... 64 1.9.3 MERTK .................................................................................................................... 65 1.9.4 Genotype- phenotype for MERTK ........................................................................... 66 1.9.5 IMPDH1 ................................................................................................................... 66 1.9.6 Genotype-phenotype correlations for IMPDH1 ....................................................... 67 1.9.7 SPATA7 .................................................................................................................... 68 1.9.8 SPATA7 Genotype-phenotype analysis .................................................................... 69 5 1.10 Other genes associated with LCA ............................................................................. 70 1.10.1 Calcium binding protein 4 (CABP4) ..................................................................... 70 1.10.2 IQ-motif containing protein B1 (IQCB1) .............................................................. 71 1.10.3 NMNAT1 ................................................................................................................ 72 1.10.4 KCNJ13 .................................................................................................................. 73 1.10.5 RD3 ........................................................................................................................ 75 1.10.6 RLBP1 : a gene associated with juvenile RD..........................................................76 1.11 Gene identification strategies to identify disease causing mutations ........................ 77 1.11.1 Genetic markers ..................................................................................................... 77 1.11.2 Restriction Fragment Length Polymorphisms ....................................................... 78 1.11.3 Microsatellite markers ........................................................................................... 78 1.11.4 Single nucleotide polymorphisms (SNPs) ............................................................. 80 1.11.5 Genomic maps ....................................................................................................... 81 1.11.6 Linkage analysis ....................................................................................................
Recommended publications
  • Genetic Analysis of Retinopathy in Type 1 Diabetes
    Genetic Analysis of Retinopathy in Type 1 Diabetes by Sayed Mohsen Hosseini A thesis submitted in conformity with the requirements for the degree of Doctor of Philosophy Institute of Medical Science University of Toronto © Copyright by S. Mohsen Hosseini 2014 Genetic Analysis of Retinopathy in Type 1 Diabetes Sayed Mohsen Hosseini Doctor of Philosophy Institute of Medical Science University of Toronto 2014 Abstract Diabetic retinopathy (DR) is a leading cause of blindness worldwide. Several lines of evidence suggest a genetic contribution to the risk of DR; however, no genetic variant has shown convincing association with DR in genome-wide association studies (GWAS). To identify common polymorphisms associated with DR, meta-GWAS were performed in three type 1 diabetes cohorts of White subjects: Diabetes Complications and Control Trial (DCCT, n=1304), Wisconsin Epidemiologic Study of Diabetic Retinopathy (WESDR, n=603) and Renin-Angiotensin System Study (RASS, n=239). Severe (SDR) and mild (MDR) retinopathy outcomes were defined based on repeated fundus photographs in each study graded for retinopathy severity on the Early Treatment Diabetic Retinopathy Study (ETDRS) scale. Multivariable models accounted for glycemia (measured by A1C), diabetes duration and other relevant covariates in the association analyses of additive genotypes with SDR and MDR. Fixed-effects meta- analysis was used to combine the results of GWAS performed separately in WESDR, ii RASS and subgroups of DCCT, defined by cohort and treatment group. Top association signals were prioritized for replication, based on previous supporting knowledge from the literature, followed by replication in three independent white T1D studies: Genesis-GeneDiab (n=502), Steno (n=936) and FinnDiane (n=2194).
    [Show full text]
  • The Connections of Wnt Pathway Components with Cell Cycle and Centrosome: Side Effects Or a Hidden Logic?
    Critical Reviews in Biochemistry and Molecular Biology ISSN: 1040-9238 (Print) 1549-7798 (Online) Journal homepage: http://www.tandfonline.com/loi/ibmg20 The connections of Wnt pathway components with cell cycle and centrosome: side effects or a hidden logic? Vítězslav Bryja , Igor Červenka & Lukáš Čajánek To cite this article: Vítězslav Bryja , Igor Červenka & Lukáš Čajánek (2017): The connections of Wnt pathway components with cell cycle and centrosome: side effects or a hidden logic?, Critical Reviews in Biochemistry and Molecular Biology, DOI: 10.1080/10409238.2017.1350135 To link to this article: http://dx.doi.org/10.1080/10409238.2017.1350135 Published online: 25 Jul 2017. Submit your article to this journal Article views: 72 View related articles View Crossmark data Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=ibmg20 Download by: [Masarykova Univerzita v Brne], [Lukas Cajanek] Date: 08 August 2017, At: 01:58 CRITICAL REVIEWS IN BIOCHEMISTRY AND MOLECULAR BIOLOGY, 2017 https://doi.org/10.1080/10409238.2017.1350135 REVIEW ARTICLE The connections of Wnt pathway components with cell cycle and centrosome: side effects or a hidden logic? Vıtezslav Bryjaa , Igor Cervenka b and Lukas Caj anekc aDepartment of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic; bMolecular and Cellular Exercise Physiology, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden; cDepartment of Histology and Embryology, Faculty of Medicine, Masaryk University, Brno, Czech Republic ABSTRACT ARTICLE HISTORY Wnt signaling cascade has developed together with multicellularity to orchestrate the develop- Received 10 April 2017 ment and homeostasis of complex structures.
    [Show full text]
  • Educational Paper Ciliopathies
    Eur J Pediatr (2012) 171:1285–1300 DOI 10.1007/s00431-011-1553-z REVIEW Educational paper Ciliopathies Carsten Bergmann Received: 11 June 2011 /Accepted: 3 August 2011 /Published online: 7 September 2011 # The Author(s) 2011. This article is published with open access at Springerlink.com Abstract Cilia are antenna-like organelles found on the (NPHP) . Ivemark syndrome . Meckel syndrome (MKS) . surface of most cells. They transduce molecular signals Joubert syndrome (JBTS) . Bardet–Biedl syndrome (BBS) . and facilitate interactions between cells and their Alstrom syndrome . Short-rib polydactyly syndromes . environment. Ciliary dysfunction has been shown to Jeune syndrome (ATD) . Ellis-van Crefeld syndrome (EVC) . underlie a broad range of overlapping, clinically and Sensenbrenner syndrome . Primary ciliary dyskinesia genetically heterogeneous phenotypes, collectively (Kartagener syndrome) . von Hippel-Lindau (VHL) . termed ciliopathies. Literally, all organs can be affected. Tuberous sclerosis (TSC) . Oligogenic inheritance . Modifier. Frequent cilia-related manifestations are (poly)cystic Mutational load kidney disease, retinal degeneration, situs inversus, cardiac defects, polydactyly, other skeletal abnormalities, and defects of the central and peripheral nervous Introduction system, occurring either isolated or as part of syn- dromes. Characterization of ciliopathies and the decisive Defective cellular organelles such as mitochondria, perox- role of primary cilia in signal transduction and cell isomes, and lysosomes are well-known
    [Show full text]
  • Ciliopathiesneuromuscularciliopathies Disorders Disorders Ciliopathiesciliopathies
    NeuromuscularCiliopathiesNeuromuscularCiliopathies Disorders Disorders CiliopathiesCiliopathies AboutAbout EGL EGL Genet Geneticsics EGLEGL Genetics Genetics specializes specializes in ingenetic genetic diagnostic diagnostic testing, testing, with with ne nearlyarly 50 50 years years of of clinical clinical experience experience and and board-certified board-certified labor laboratoryatory directorsdirectors and and genetic genetic counselors counselors reporting reporting out out cases. cases. EGL EGL Genet Geneticsics offers offers a combineda combined 1000 1000 molecular molecular genetics, genetics, biochemical biochemical genetics,genetics, and and cytogenetics cytogenetics tests tests under under one one roof roof and and custom custom test testinging for for all all medically medically relevant relevant genes, genes, for for domestic domestic andand international international clients. clients. EquallyEqually important important to to improving improving patient patient care care through through quality quality genetic genetic testing testing is is the the contribution contribution EGL EGL Genetics Genetics makes makes back back to to thethe scientific scientific and and medical medical communities. communities. EGL EGL Genetics Genetics is is one one of of only only a afew few clinical clinical diagnostic diagnostic laboratories laboratories to to openly openly share share data data withwith the the NCBI NCBI freely freely available available public public database database ClinVar ClinVar (>35,000 (>35,000 variants variants on on >1700 >1700 genes) genes) and and is isalso also the the only only laboratory laboratory with with a a frefree oen olinnlein dea dtabtaabsaes (eE m(EVmCVlaCslas)s,s f)e, afetuatruinrgin ag vaa vraiarniatn ctl acslasisfiscifiactiaotino sne saercahrc ahn adn rde rpeoprot rrte rqeuqeuset sint tinetrefarcfaec, ew, hwichhic fha cfailcitialiteatse rsa praidp id interactiveinteractive curation curation and and reporting reporting of of variants.
    [Show full text]
  • Refractive Error Changes in Cortical, Nuclear and Posterior Subcapsular Cataracts
    1524 Refractive error changes in cortical, nuclear and posterior subcapsular cataracts. D.B. Elliott & K. Pesudovs . Department of Optometry, University of Bradford, Bradford, United Kingdom.. Purpose • To determine the effect of the three main morphological types of age-related cataract on refractive error. Background • The increase in myopia in some patients with age-related nuclear cataract is well known (Brown & Hill, 1987). This change accounts for the “second sight of the elderly” in which the myopic shift provides normal reading ability without the need for spectacles. Distance vision, however, worsens. • Planter (1981) suggested that cortical opacity can induce hyperopic shifts. However, this claim has not been repeated since and no firm evidence is available. • Review papers suggest that cortical opacity can induce astigmatic changes (Brown, 1993). However, these reports were based on clinical impression with no supporting data. • . The prevalence of uncorrected refractive error in the elderly population is high (Wormald et al., 1992). It is likely that a reasonable proportion of these patients have refractive error changes induced by cataract. • It has been suggested that a delay in operating on age-related cataract of 10 years could reduce the number of patients requiring cataract surgery (Kupfer, 1985). The possible role of correcting cataract-induced refractive error to delay the need for surgery should be explored. Subjects • 98 elderly subjects (mean age 67 ± 8 years) were recruited. • 77 subjects had one type of morphological cataract: 34 subjects had cortical cataract, 21 had nuclear cataract and 21 had posterior subcapsular cataract (PSC). • 22 subjects had normal, healthy eyes. • Ocular screening excluded amblyopia, strabismus, eye disease or surgery.
    [Show full text]
  • Fact Sheet: Refractive Errors
    Fact Sheet: Refractive Errors More than 11 million Americans have common vision problems that can be corrected with the use of prescriptive eyewear such as glasses or contact lenses.1 These conditions are known as refractive errors and they occur when the eye doesn’t correctly bend, or ―refract,‖ light as it enters the eye. Common refractive errors include the following: o Nearsightedness (also called myopia)—A condition where objects up close appear clearly, while objects far away appear blurry. With nearsightedness, light comes to focus in front of the retina instead of on the retina. o Farsightedness (also called hyperopia)—A common type of refractive error where distant objects may be seen more clearly than objects that are near. However, people experience farsightedness differently. Some people may not notice any problems with their vision, especially when they are young. For people with significant farsightedness, vision can be blurry for objects at any distance, near or far. o Astigmatism—A condition in which the eye does not focus light evenly onto the retina, the light-sensitive tissue at the back of the eye. This can cause images to appear blurry and stretched out. o Presbyopia—An age-related condition in which the ability to focus up close becomes more difficult. As the eye ages, the lens can no longer change shape enough to allow the eye to focus close objects clearly. Refractive errors are one of the most common—and correctable—causes of visual impairment in the United States. According to a recent study led by the National Eye Institute (NEI), approximately half of all American adults don’t have the 20/20 vision physicians consider optimal due to refractive errors.2 Women experience refractive error more frequently than men: Twenty-six percent more women aged 12 and older have uncorrected visual impairment due to refractive error compared with men aged 12 and older.
    [Show full text]
  • Genetic Determinants Underlying Rare Diseases Identified Using Next-Generation Sequencing Technologies
    Western University Scholarship@Western Electronic Thesis and Dissertation Repository 8-2-2018 1:30 PM Genetic determinants underlying rare diseases identified using next-generation sequencing technologies Rosettia Ho The University of Western Ontario Supervisor Hegele, Robert A. The University of Western Ontario Graduate Program in Biochemistry A thesis submitted in partial fulfillment of the equirr ements for the degree in Master of Science © Rosettia Ho 2018 Follow this and additional works at: https://ir.lib.uwo.ca/etd Part of the Medical Genetics Commons Recommended Citation Ho, Rosettia, "Genetic determinants underlying rare diseases identified using next-generation sequencing technologies" (2018). Electronic Thesis and Dissertation Repository. 5497. https://ir.lib.uwo.ca/etd/5497 This Dissertation/Thesis is brought to you for free and open access by Scholarship@Western. It has been accepted for inclusion in Electronic Thesis and Dissertation Repository by an authorized administrator of Scholarship@Western. For more information, please contact [email protected]. Abstract Rare disorders affect less than one in 2000 individuals, placing a huge burden on individuals, families and the health care system. Gene discovery is the starting point in understanding the molecular mechanisms underlying these diseases. The advent of next- generation sequencing has accelerated discovery of disease-causing genetic variants and is showing numerous benefits for research and medicine. I describe the application of next-generation sequencing, namely LipidSeq™ ‒ a targeted resequencing panel for the identification of dyslipidemia-associated variants ‒ and whole-exome sequencing, to identify genetic determinants of several rare diseases. Utilization of next-generation sequencing plus associated bioinformatics led to the discovery of disease-associated variants for 71 patients with lipodystrophy, two with early-onset obesity, and families with brachydactyly, cerebral atrophy, microcephaly-ichthyosis, and widow’s peak syndrome.
    [Show full text]
  • European School of Genetic Medicine Eye Genetics
    European School of Genetic Medicine th 4 Course in Eye Genetics Bertinoro, Italy, September 27-29, 2015 Bertinoro University Residential Centre Via Frangipane, 6 – Bertinoro www.ceub.it Course Directors: R. Allikmets (Columbia University, New York) A. Ciardella (U.O. Oftalmologia, Policlinico Sant’ Orsola, Bologna) B. P. Leroy (Ghent University, Ghent) M. Seri (U.O Genetica Medica, Bologna). th 4 Course in Eye Genetics Bertinoro, Italy, September 27-29, 2015 CONTENTS PROGRAMME 3 ABSTRACTS OF LECTURES 6 ABSTRACTS OF STUDENTS POSTERS 26 STUDENTS WHO IS WHO 39 FACULTY WHO IS WHO 41 2 4TH COURSE IN EYE GENETICS Bertinoro University Residential Centre Bertinoro, Italy, September 27-29, 2015 Arrival day: Saturday, September 26th September 27 8:30 - 8:40 Welcome 8:40 - 9:10 History of Medical Genetics Giovanni Romeo 9:15 - 10:00 2 parallel talks: (40 min + 5 min discussion) Garrison Room 1. Overview of clinical ophthalmology for basic scientists Antonio Ciardella Jacopo da Bertinoro Room 2. Overview of basic medical genetics for ophthalmologists Bart Leroy 10:05 - 11:35 2 talks (40 min + 5 min discussion) 3. Stargardt disease, the complex simple retinal disorder Rando Allikmets 4. Overview of inherited corneal disorders Graeme Black 11:35 - 12:00 Break 12:00 - 13:30 2 talks (40 min + 5 min discussion) 1. Molecular basis of non-syndromic and syndromic retinal and vitreoretinal diseases Wolfgang Berger 2. Introduction to next-generation sequencing for eye diseases Lonneke Haer-Wigman 13:30 - 14:30 Lunch 14:30 - 16:15 3 parallel workshops
    [Show full text]
  • Leber Congenital Amaurosis Due to CEP290 Mutations – Severe Vision Impairment with a High Unmet Medical Need: a Review Author and Journal Details: Bart P
    This plain-language summary (or PLS) describes a paper on Leber congenital amaurosis 10 that was published in a medical journal called “Retina”. Title of the paper: Leber congenital amaurosis due to CEP290 mutations – severe vision impairment with a high unmet medical need: a review Author and journal details: Bart P. Leroy, David G. Birch, Jacque L. Duncan, Byron L. Lam, Robert K. Koenekoop, Fernanda B. O. Porto, Stephen R. Russel, Aniz Girach. Retina 2021;doi:10.1097/IAE.0000000000003133. Online ahead of print. What does this paper report on? • The authors of this paper reviewed what scientists know about the genetic eye disease called Leber congenital amaurosis 10 (also known as LCA10). They looked at the scientific articles on this subject that have been published in high-quality medical journals Why was this research needed? • Tying together separate pieces of scientific evidence about a disease can help us to understand the disease better. It also helps identify where there may be areas of care for people with the disease that need to be improved. We call these gaps “unmet medical needs” • Bringing evidence together in this way is especially important for rare diseases as it improves awareness among healthcare professionals of the needs of people living with the disease The authors of the paper are expert eye doctors working at specialist centers in Belgium, Brazil, Canada, and the USA; one of the authors is an employee of ProQR Therapeutics. This PLS has been developed in collaboration with Bart Leroy (an author on the original paper), Francesca Diodati and Matthew Carr, with medical writing assistance provided by ApotheCom.
    [Show full text]
  • Genes in Eyecare Geneseyedoc 3 W.M
    Genes in Eyecare geneseyedoc 3 W.M. Lyle and T.D. Williams 15 Mar 04 This information has been gathered from several sources; however, the principal source is V. A. McKusick’s Mendelian Inheritance in Man on CD-ROM. Baltimore, Johns Hopkins University Press, 1998. Other sources include McKusick’s, Mendelian Inheritance in Man. Catalogs of Human Genes and Genetic Disorders. Baltimore. Johns Hopkins University Press 1998 (12th edition). http://www.ncbi.nlm.nih.gov/Omim See also S.P.Daiger, L.S. Sullivan, and B.J.F. Rossiter Ret Net http://www.sph.uth.tmc.edu/Retnet disease.htm/. Also E.I. Traboulsi’s, Genetic Diseases of the Eye, New York, Oxford University Press, 1998. And Genetics in Primary Eyecare and Clinical Medicine by M.R. Seashore and R.S.Wappner, Appleton and Lange 1996. M. Ridley’s book Genome published in 2000 by Perennial provides additional information. Ridley estimates that we have 60,000 to 80,000 genes. See also R.M. Henig’s book The Monk in the Garden: The Lost and Found Genius of Gregor Mendel, published by Houghton Mifflin in 2001 which tells about the Father of Genetics. The 3rd edition of F. H. Roy’s book Ocular Syndromes and Systemic Diseases published by Lippincott Williams & Wilkins in 2002 facilitates differential diagnosis. Additional information is provided in D. Pavan-Langston’s Manual of Ocular Diagnosis and Therapy (5th edition) published by Lippincott Williams & Wilkins in 2002. M.A. Foote wrote Basic Human Genetics for Medical Writers in the AMWA Journal 2002;17:7-17. A compilation such as this might suggest that one gene = one disease.
    [Show full text]
  • Ciliopathies Gene Panel
    Ciliopathies Gene Panel Contact details Introduction Regional Genetics Service The ciliopathies are a heterogeneous group of conditions with considerable phenotypic overlap. Levels 4-6, Barclay House These inherited diseases are caused by defects in cilia; hair-like projections present on most 37 Queen Square cells, with roles in key human developmental processes via their motility and signalling functions. Ciliopathies are often lethal and multiple organ systems are affected. Ciliopathies are London, WC1N 3BH united in being genetically heterogeneous conditions and the different subtypes can share T +44 (0) 20 7762 6888 many clinical features, predominantly cystic kidney disease, but also retinal, respiratory, F +44 (0) 20 7813 8578 skeletal, hepatic and neurological defects in addition to metabolic defects, laterality defects and polydactyly. Their clinical variability can make ciliopathies hard to recognise, reflecting the ubiquity of cilia. Gene panels currently offer the best solution to tackling analysis of genetically Samples required heterogeneous conditions such as the ciliopathies. Ciliopathies affect approximately 1:2,000 5ml venous blood in plastic EDTA births. bottles (>1ml from neonates) Ciliopathies are generally inherited in an autosomal recessive manner, with some autosomal Prenatal testing must be arranged dominant and X-linked exceptions. in advance, through a Clinical Genetics department if possible. Referrals Amniotic fluid or CV samples Patients presenting with a ciliopathy; due to the phenotypic variability this could be a diverse set should be sent to Cytogenetics for of features. For guidance contact the laboratory or Dr Hannah Mitchison dissecting and culturing, with ([email protected]) / Prof Phil Beales ([email protected]) instructions to forward the sample to the Regional Molecular Genetics Referrals will be accepted from clinical geneticists and consultants in nephrology, metabolic, laboratory for analysis respiratory and retinal diseases.
    [Show full text]
  • Functional Characterization of the Human RPGR Proximal Promoter
    Biochemistry and Molecular Biology Functional Characterization of the Human RPGR Proximal Promoter Xinhua Shu,*,1,2 Julie R. Simpson,2 Alan W. Hart,2 Zhihong Zeng,3 Sarita Rani Patnaik,1 Philippe Gautier,2 Emma Murdoch,2 Brian Tulloch,2 and Alan F. Wright*,2 PURPOSE. Mutations in the retinitis pigmentosa (RP) GTPase promoter will facilitate understanding of the functional role regulator (RPGR) gene account for more than 70% of X-linked of RPGR in the retina and gene therapy of X-linked RP. (Invest RP cases. This study aims to characterize the proximal Ophthalmol Vis Sci. 2012;53:3951–3958) DOI:10.1167/ promoter region of the human RPGR gene. iovs.11-8811 0 METHODS. The 5 -flanking region (5 kb) of human RPGR was cloned and sequenced. A potential transcription start site and etinitis pigmentosa (RP) is a genetically heterogeneous transcription factor binding motifs were identified by bio- Rgroup of retinal degenerations that affect 1 in 4000 in the informatic analysis. Constructs containing the putative human general population.1,2 Most cases are inherited in an autosomal RPGR promoter region upstream of a luciferase reporter gene dominant, autosomal recessive, X-linked, or mitochondrial were generated and analyzed by transient transfection and manner, but oligogenic inheritance has been established in a luciferase assays. Transgenic mouse lines carrying a 3-kb small proportion of families.3 X-linked RP (XLRP) is one of the human RPGR promoter sequence fused to lacZ were generated most consistently severe forms of RP, with a reported average and RPGR proximal promoter activity was analyzed by X-gal age at onset of 7.2 6 1.7 years.4 XLRP affects 10% to 20% of all staining.
    [Show full text]