1
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Huizing M, Malicdan MCV, Wang JA, Pri-Chen H, Hess RA, Fischer R, O'Brien KJ, Merideth MA, Gahl WA, Gochuico BR. Hermansky-Pudlak syndrome: Mutation update. Hum Mutat 2020; 41:543-580. [PMID: 31898847 DOI: 10.1002/humu.23968] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 12/06/2019] [Accepted: 12/26/2019] [Indexed: 12/14/2022]
Abstract
Hermansky-Pudlak syndrome (HPS) is a group of 10 autosomal recessive multisystem disorders, each defined by the deficiency of a specific gene. HPS-associated genes encode components of four ubiquitously expressed protein complexes: Adaptor protein-3 (AP-3) and biogenesis of lysosome-related organelles complex-1 (BLOC-1) through -3. All individuals with HPS exhibit albinism and a bleeding diathesis; additional features occur depending on the defective protein complex. Pulmonary fibrosis is associated with AP-3 and BLOC-3 deficiency, immunodeficiency with AP-3 defects, and gastrointestinal symptoms are more prevalent and severe in BLOC-3 deficiency. Therefore, identification of the HPS subtype is valuable for prognosis, clinical management, and treatment options. The prevalence of HPS is estimated at 1-9 per 1,000,000. Here we summarize 264 reported and novel variants in 10 HPS genes and estimate that ~333 Puerto Rican HPS subjects and ~385 with other ethnicities are reported to date. We provide pathogenicity predictions for missense and splice site variants and list variants with high minor allele frequencies. Current cellular and clinical aspects of HPS are also summarized. This review can serve as a manifest for molecular diagnostics and genetic counseling aspects of HPS.
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Affiliation(s)
- Marjan Huizing
- Human Biochemical Genetics Section, Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - May C V Malicdan
- Human Biochemical Genetics Section, Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Jennifer A Wang
- Human Biochemical Genetics Section, Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Hadass Pri-Chen
- Human Biochemical Genetics Section, Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland.,Metabolic Disease Unit, Edmond and Lily Safra Children's Hospital, Sheba Medical Center, Tel Hashomer and Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Richard A Hess
- Human Biochemical Genetics Section, Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Roxanne Fischer
- Human Biochemical Genetics Section, Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Kevin J O'Brien
- Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Melissa A Merideth
- Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - William A Gahl
- Human Biochemical Genetics Section, Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Bernadette R Gochuico
- Human Biochemical Genetics Section, Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
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2
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Abstract
The Hermansky-Pudlak syndrome (HPS) is a rare disease characterized by oculocutaneous albinism and prolonged bleeding. HPS is caused by alterations in HPS1-10 and their related genes, comprising the biogenesis of lysosome-related organelles complex 1–3 and adapter protein 3. Here, we report a Japanese patient with HPS associated with mild hypopigmentation, nystagmus, and impaired visual acuity. Sequencing analyses of the mRNA of this patient revealed new deletions (ΔGA and ΔG) in the HPS5 gene. This was the first case of HPS5 gene deficiency in Japan, and the two above-mentioned deletions have not yet been reported among patients with HPS5.
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3
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Wentzell R, Santoso S, Zieger B, Sandrock-Lang K. Angeborene Thrombozytenfunktionsstörungen. Hamostaseologie 2017; 36:178-86. [DOI: 10.5482/hamo-14-11-0067] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2014] [Accepted: 01/30/2015] [Indexed: 11/05/2022] Open
Abstract
ZusammenfassungAngeborene Thrombozytopathien können zu Blutungssymptomen unterschiedlichen Schweregrades führen, da die Thrombozyten nicht mehr ihre Funktion nach einer Gefäß-verletzung erfüllen können. In manchen Fällen sind Thrombozytopathien schwierig zu diagnostizieren und können Probleme in der Therapie und im Management verursachen. Dieser Review beschreibt den klinischen und molekulargenetischen Phänotyp der verschiedenen angeborenen Thrombozytopathien. Die angeborenen Thrombozytopathien werden entsprechend des Thrombozytendefekts eingeteilt: Rezeptordefekte (Adhäsion oder Aggregation), Sekretionsdefekte und Zytoskelettdefekte.Die am besten charakterisierten thrombozytären Rezeptordefekte sind die Glanzmann Thrombasthenie (Defekt des Integrins [uni03B1]IIb[uni03B2]3) und das Bernard-Soulier Syndrom (Defekt des GPIb/IX/V Rezeptors). Umfassende Fall-berichte über die Blutungsdiathese sowie die Untersuchung der Thrombozytenaggregation bzw. -agglutination und Rezeptorexpression von Patienten, die an der Glanzmann Thrombasthenie (GT) oder am Bernard-Soulier Syndrom (BSS) leiden, sollen diesen Review ergänzen. Darüber hinaus wird das HermanskyPudlak Syndrom (HPS) als eine bedeutende Störung der [uni03B4]-Granula Sekretion zusammen mit einer Fallbeschreibung eines Patienten, der an HPS Typ 1 leidet, beschrieben.
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4
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Botero JP, Chen D, Majerus JA, Coon LM, He R, Warad DM, Pruthi RK, Nichols WL. Hermansky-Pudlak syndrome subtype 5 (HPS-5) novel mutation in a 65 year-old with oculocutaneous hypopigmentation and mild bleeding diathesis: The importance of recognizing a subtle phenotype. Platelets 2017; 29:91-94. [DOI: 10.1080/09537104.2017.1361019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
| | - Dong Chen
- Special Coagulation Laboratory, Mayo Clinic, Rochester, MN, USA
- Division of Hematopathology, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | | | - Lea M. Coon
- Special Coagulation Laboratory, Mayo Clinic, Rochester, MN, USA
| | - Rong He
- Special Coagulation Laboratory, Mayo Clinic, Rochester, MN, USA
- Division of Hematopathology, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | - Deepti M. Warad
- Special Coagulation Laboratory, Mayo Clinic, Rochester, MN, USA
| | - Rajiv K. Pruthi
- Division of Hematology, Department of Medicine, Mayo Clinic, Rochester, MN, USA
- Special Coagulation Laboratory, Mayo Clinic, Rochester, MN, USA
- Division of Hematopathology, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | - William L. Nichols
- Division of Hematology, Department of Medicine, Mayo Clinic, Rochester, MN, USA
- Special Coagulation Laboratory, Mayo Clinic, Rochester, MN, USA
- Division of Hematopathology, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
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5
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Loredana Asztalos M, Schafernak KT, Gray J, Berry A, Paller AS, Mancini AJ. Hermansky-Pudlak syndrome: Report of two patients with updated genetic classification and management recommendations. Pediatr Dermatol 2017; 34:638-646. [PMID: 29044644 DOI: 10.1111/pde.13266] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Hermansky-Pudlak syndrome (HPS) is a rare autosomal recessive disorder caused by mutations in one of nine genes involved in the packaging and formation of specialized lysosomes, including melanosomes and platelet-dense granules. The cardinal features are pigmentary dilution, bleeding diathesis, and accumulation of ceroid-like material in reticuloendothelial cells. Pulmonary fibrosis induced by tissue damage is seen in the most severe forms, and one subtype is characterized by immunodeficiency. We describe two patients with HPS type 1 and review the updated gene-based classification, clinical features, and recommendations for evaluation and follow-up.
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Affiliation(s)
- Manuela Loredana Asztalos
- Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, USA.,Department of Pediatrics, Pathology and Laboratory Medicine , Northwestern University, Chicago, IL, USA.,Department of Dermatology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Kristian T Schafernak
- Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, USA.,Department of Pediatrics, Pathology and Laboratory Medicine , Northwestern University, Chicago, IL, USA.,Department of Dermatology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Jayla Gray
- Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, USA.,Department of Pediatrics, Pathology and Laboratory Medicine , Northwestern University, Chicago, IL, USA.,Department of Dermatology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Adam Berry
- Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, USA.,Department of Pediatrics, Pathology and Laboratory Medicine , Northwestern University, Chicago, IL, USA.,Department of Dermatology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Amy S Paller
- Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, USA.,Department of Pediatrics, Pathology and Laboratory Medicine , Northwestern University, Chicago, IL, USA.,Department of Dermatology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Anthony J Mancini
- Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, USA.,Department of Pediatrics, Pathology and Laboratory Medicine , Northwestern University, Chicago, IL, USA.,Department of Dermatology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
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6
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Marti A, Lasseaux E, Ezzedine K, Léauté-Labrèze C, Boralevi F, Paya C, Coste V, Deroissart V, Arveiler B, Taieb A, Morice-Picard F. Lessons of a day hospital: Comprehensive assessment of patients with albinism in a European setting. Pigment Cell Melanoma Res 2017; 31:318-329. [DOI: 10.1111/pcmr.12651] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2017] [Accepted: 09/22/2017] [Indexed: 12/24/2022]
Affiliation(s)
- Aurélie Marti
- Paediatric Dermatology Unit; National Reference Center for Rare Skin Disorders; Hôpital Pellegrin-Enfants; Bordeaux University Hospitals; Bordeaux France
| | | | - Khaled Ezzedine
- Department of Dermatology; AP-HP; Hôpital Henri-Mondor; Créteil France
| | - Christine Léauté-Labrèze
- Paediatric Dermatology Unit; National Reference Center for Rare Skin Disorders; Hôpital Pellegrin-Enfants; Bordeaux University Hospitals; Bordeaux France
| | - Franck Boralevi
- Paediatric Dermatology Unit; National Reference Center for Rare Skin Disorders; Hôpital Pellegrin-Enfants; Bordeaux University Hospitals; Bordeaux France
| | - Clément Paya
- Ophthalmology Department; CHU de Bordeaux; Bordeaux France
| | | | - Vincent Deroissart
- Institute of Public Health; Epidemiology and Development “ISPED”; Bordeaux University; Bordeaux France
| | - Benoit Arveiler
- Molecular Genetics Laboratory; CHU de Bordeaux; Bordeaux France
- Unité INSERM U1211; Maladies Rares: Génétique et Métabolisme; Bordeaux France
| | - Alain Taieb
- Paediatric Dermatology Unit; National Reference Center for Rare Skin Disorders; Hôpital Pellegrin-Enfants; Bordeaux University Hospitals; Bordeaux France
- Unité INSERM 1035; BMGIC; Immuno-dermatology ATIP-AVENIR; University of Bordeaux; Bordeaux France
| | - Fanny Morice-Picard
- Paediatric Dermatology Unit; National Reference Center for Rare Skin Disorders; Hôpital Pellegrin-Enfants; Bordeaux University Hospitals; Bordeaux France
- Molecular Genetics Laboratory; CHU de Bordeaux; Bordeaux France
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7
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Michaud V, Lasseaux E, Plaisant C, Verloes A, Perdomo-Trujillo Y, Hamel C, Elcioglu NH, Leroy B, Kaplan J, Jouk PS, Lacombe D, Fergelot P, Morice-Picard F, Arveiler B. Clinico-molecular analysis of eleven patients with Hermansky-Pudlak type 5 syndrome, a mild form of HPS. Pigment Cell Melanoma Res 2017. [PMID: 28640947 DOI: 10.1111/pcmr.12608] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Hermansky-Pudlak syndrome (HPS), first described in 1959, is a rare form of syndromic oculocutaneous albinism associated with bleeding diathesis and in some cases pulmonary fibrosis and granulomatous colitis. All 10 HPS types are caused by defects in vesicle trafficking of lysosome-related organelles (LRO) proteins. The HPS5 protein associates with HPS3 and HPS6 to form the biogenesis of lysosome-related organelles complex-2 (BLOC-2). Here, we report the clinical and genetic data of 11 patients with HPS-5 analyzed in our laboratory. We report 11 new pathogenic variants. The 11 patients present with ocular features that are typical for albinism, with mild hypopigmentation, and with no other major complication, apart from a tendency to bleed. HPS-5 therefore appears as a mild form of HPS, which is often clinically undistinguishable from mild oculocutaneous or ocular forms of albinism. Molecular analysis is therefore required to establish the diagnosis of this mild HPS form, which has consequences in terms of prognosis and of clinical management of the patients.
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Affiliation(s)
- Vincent Michaud
- Service Génétique Médicale, CHU de Bordeaux, Bordeaux, France
| | | | | | - Alain Verloes
- Département de Génétique, Hôpital Robert Debré, Paris, France
| | | | - Christian Hamel
- Service d'Ophtalmologie, CHU de Montpellier, Montpellier, France
| | - Nursel H Elcioglu
- Department of Pediatric Genetics, Marmara University Medical School, Istanbul, Turkey.,Eastern Mediterranean University Medical School, Cyprus, Turkey
| | - Bart Leroy
- Center for Medical Genetics, Ghent University Hospital, Gent, Belgium
| | - Josseline Kaplan
- Laboratoire Génétique Moléculaire, Hôpital Necker-Enfants Malades, Paris, France
| | - Pierre-Simon Jouk
- Service Génétique Clinique, CHU de Grenoble Site La Tronche, Hôpital Couple Enfant, Grenoble, France
| | - Didier Lacombe
- Service Génétique Médicale, CHU de Bordeaux, Bordeaux, France.,Unité INSERM U1211, Maladies Rares: Génétique et Métabolisme, Bordeaux, France
| | - Patricia Fergelot
- Service Génétique Médicale, CHU de Bordeaux, Bordeaux, France.,Unité INSERM U1211, Maladies Rares: Génétique et Métabolisme, Bordeaux, France
| | - Fanny Morice-Picard
- Service Génétique Médicale, CHU de Bordeaux, Bordeaux, France.,Service de Dermatologie Pédiatrique, Centre de Référence Maladies Rares de la Peau, CHU de Bordeaux, Bordeaux, France
| | - Benoit Arveiler
- Service Génétique Médicale, CHU de Bordeaux, Bordeaux, France.,Unité INSERM U1211, Maladies Rares: Génétique et Métabolisme, Bordeaux, France
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8
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Stephen J, Yokoyama T, Tolman NJ, O’Brien KJ, Nicoli ER, Brooks BP, Huryn L, Titus SA, Adams DR, Chen D, Gahl WA, Gochuico BR, Malicdan MCV. Cellular and molecular defects in a patient with Hermansky-Pudlak syndrome type 5. PLoS One 2017; 12:e0173682. [PMID: 28296950 PMCID: PMC5351877 DOI: 10.1371/journal.pone.0173682] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Accepted: 02/24/2017] [Indexed: 02/05/2023] Open
Abstract
Hermansky-Pudlak syndrome (HPS) is a heterogeneous group of genetic disorders typically manifesting with tyrosinase-positive oculocutaneous albinism, bleeding diathesis, and pulmonary fibrosis, in some subtypes. Most HPS subtypes are associated with defects in Biogenesis of Lysosome-related Organelle Complexes (BLOCs), which are groups of proteins that function together in the formation and/or trafficking of lysosomal-related endosomal compartments. BLOC-2, for example, consists of the proteins HPS3, HPS5, and HPS6. Here we present an HPS patient with defective BLOC-2 due to a novel intronic mutation in HPS5 that activates a cryptic acceptor splice site. This mutation leads to the insertion of nine nucleotides in-frame and results in a reduced amount of HPS5 at the transcript and protein level. In studies using skin fibroblasts derived from the proband and two other individuals with HPS-5, we found a perinuclear distribution of acidified organelles in patient cells compared to controls. Our results suggest the role of HPS5 in the endo-lysosomal dynamics of skin fibroblasts.
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Affiliation(s)
- Joshi Stephen
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Tadafumi Yokoyama
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Nathanial J. Tolman
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Kevin J. O’Brien
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Elena-Raluca Nicoli
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Brian P. Brooks
- Ophthalmic Genetics & Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Laryssa Huryn
- Ophthalmic Genetics & Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Steven A. Titus
- Division of Pre-clinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, United States of America
| | - David R. Adams
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, National Institutes of Health, Bethesda, Maryland, United States of America
- Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Dong Chen
- Division of Hematopathology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - William A. Gahl
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, United States of America
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, National Institutes of Health, Bethesda, Maryland, United States of America
- Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Bernadette R. Gochuico
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, United States of America
- * E-mail:
| | - May Christine V. Malicdan
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, National Institutes of Health, Bethesda, Maryland, United States of America
- Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, United States of America
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9
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Sánchez-Guiu I, Torregrosa JM, Velasco F, Antón AI, Lozano ML, Vicente V, Rivera J. Hermansky-Pudlak syndrome. Overview of clinical and molecular features and case report of a new HPS-1 variant. Hamostaseologie 2014; 34:301-9. [PMID: 25117010 DOI: 10.5482/hamo-14-06-0024] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Accepted: 08/04/2014] [Indexed: 12/30/2022] Open
Abstract
Hermansky-Pudlak syndrome (HPS) is a rare, autosomal recessive disorder affecting lysosome-related organelles (LRO), including dense platelet granules. HPS causes oculocutaneous hypopigmentation, bleeding diathesis and granulomatous colitis or pulmonary fibrosis. To date, there is no curative treatment and the clinical management depends on the severity of symptoms. A prompt diagnosis of HPS patients could improve their quality of life and clinical management. However, the absence of a specific platelet function test, the wide molecular heterogeneity, and the lack of phenotype-genotype correlations hamper the rapid diagnosis. Nine subtypes of HPS have been identified as a result of mutations in nine genes that codify for proteins involved in formation and shuttle of the LRO. The molecular characterization of patients and knowledge derived from animal models of HPS contribute to the understanding of biogenesis and function of the LRO. This paper describes a patient with a novel homozygous nonsense mutation causing HPS and provides a review of the literature focusing on recent advances in the molecular characterization and physiopathology of HPS.
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Affiliation(s)
| | | | | | | | | | | | - J Rivera
- José Rivera, PhD., Centro Regional de Hemodonación, C/ Ronda de Garay s/n, Murcia, 30003, Spain, Tel. +34/968/34 19 90; Fax +34/968/261 91, E-mail:
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10
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Abstract
Hermansky-Pudlak Syndrome (HPS) is a set of genetically heterogeneous diseases caused by mutations in one of nine known HPS genes. HPS patients display oculocutaneous hypopigmentation and bleeding diathesis and, depending on the disease subtype, pulmonary fibrosis, congenital nystagmus, reduced visual acuity, and platelet aggregation deficiency. Mouse models for all known HPS subtypes have contributed greatly to our understanding of the disease, but many of the molecular and cellular mechanisms underlying HPS remain unknown. Here, we characterize ocular defects in the zebrafish (Danio rerio) mutant snow white (snw), which possesses a recessive, missense mutation in hps5 (hps5I76N). Melanosome biogenesis is disrupted in snw/hps5 mutants, resulting in hypopigmentation, a significant decrease in the number, size, and maturity of melanosomes, and the presence of ectopic multi-melanosome clusters throughout the mutant retina and choroid. snw/hps5I76N is the first Hps5 mutation identified within the N-terminal WD40 repeat protein-protein binding domain. Through in vitro coexpression assays, we demonstrate that Hps5I76N retains the ability to bind its protein complex partners, Hps3 and Hps6. Furthermore, while Hps5 and Hps6 stabilize each other's expression, this stabilization is disrupted by Hps5I76N. The snw/hps5I76N mutant provides a valuable resource for structure-function analyses of Hps5 and enables further elucidation of the molecular and cellular mechanisms underlying HPS.
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11
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Sandrock K, Zieger B. Current Strategies in Diagnosis of Inherited Storage Pool Defects. ACTA ACUST UNITED AC 2010; 37:248-258. [PMID: 21113247 DOI: 10.1159/000320279] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2010] [Accepted: 08/17/2010] [Indexed: 01/24/2023]
Abstract
Inherited platelet defects lead to bleeding symptoms of varying severity. Typically, easy bruising, petechiae, epistaxis, and mucocutaneous bleeding are observed in affected patients. The platelet defects are classified into disorders affecting either platelet surface receptors or intracellular organelles of platelets. The latter are represented by platelet storage pool diseases (SPD) which share a defect of platelet granules. Platelet α-granules, δ-granules, or both may be affected resulting in the clinical picture of α-SPD (e.g. Gray platelet syndrome, Quebec platelet disorder, arthrogryposis, renal dysfunction, and cholestasis syndrome), δ-SPD (e.g. Hermansky-Pudlak syndrome, Chediak-Higashi syndrome, Griscelli syndrome), or αδ-SPD (e.g. X-linked thrombocytopenia, Wiskott-Aldrich syndrome). Diagnosis of SPD is very extensive and requires platelet aggregation and flow cytometry analyses with interpretation from a specialist. Many of these disorders share common treatments, however, efficacy can vary between different patients. Therapy regiments with tranexamic acid, DDAVP, activated FVIIa, and platelet transfusions have been published. Stem cell or bone marrow transplantations are preserved for severe defects. Here, we describe the pathophysiology, clinical manifestations, and diagnosis of the major human SPDs.
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Affiliation(s)
- Kirstin Sandrock
- Department of Pediatrics and Adolescent Medicine, University Medical Center Freiburg, Germany
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