1
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Yano N, Chong PF, Kojima KK, Miyoshi T, Luqmen-Fatah A, Kimura Y, Kora K, Kayaki T, Maizuru K, Hayashi T, Yokoyama A, Ajiro M, Hagiwara M, Kondo T, Kira R, Takita J, Yoshida T. Long-read sequencing identifies an SVA_D retrotransposon insertion deep within the intron of ATP7A as a novel cause of occipital horn syndrome. J Med Genet 2024; 61:950-958. [PMID: 38960580 DOI: 10.1136/jmg-2024-110056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2024] [Accepted: 06/25/2024] [Indexed: 07/05/2024]
Abstract
BACKGROUND SINE-VNTR-Alu (SVA) retrotransposons move from one genomic location to another in a 'copy-and-paste' manner. They continue to move actively and cause monogenic diseases through various mechanisms. Currently, disease-causing SVA retrotransposons are classified into human-specific young SVA_E or SVA_F subfamilies. In this study, we identified an evolutionarily old SVA_D retrotransposon as a novel cause of occipital horn syndrome (OHS). OHS is an X-linked, copper metabolism disorder caused by dysfunction of the copper transporter, ATP7A. METHODS We investigated a 16-year-old boy with OHS whose pathogenic variant could not be detected via routine molecular genetic analyses. RESULTS A 2.8 kb insertion was detected deep within the intron of the patient's ATP7A gene. This insertion caused aberrant mRNA splicing activated by a new donor splice site located within it. Long-read circular consensus sequencing enabled us to accurately read the entire insertion sequence, which contained highly repetitive and GC-rich segments. Consequently, the insertion was identified as an SVA_D retrotransposon. Antisense oligonucleotides (AOs) targeting the new splice site restored the expression of normal transcripts and functional ATP7A proteins. AO treatment alleviated excessive accumulation of copper in patient fibroblasts in a dose-dependent manner. Pedigree analysis revealed that the retrotransposon had moved into the OHS-causing position two generations ago. CONCLUSION This is the first report of a human monogenic disease caused by the SVA_D retrotransposon. The fact that the evolutionarily old SVA_D is still actively transposed, leading to increased copy numbers may make a notable impact on rare genetic disease research.
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Affiliation(s)
- Naoko Yano
- Department of Pediatrics, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Pin Fee Chong
- Department of Pediatric Neurology, Fukuoka Children's Hospital, Fukuoka, Japan
- Department of Pediatrics, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Kenji K Kojima
- Genetic Information Research Institute, Cupertino, CA, USA
| | - Tomoichiro Miyoshi
- Laboratory for Retrotransposon Dynamics, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan
- Department of Gene Mechanisms, Kyoto University Graduate School of Biostudies, Kyoto, Japan
| | - Ahmad Luqmen-Fatah
- Laboratory for Retrotransposon Dynamics, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan
| | - Yu Kimura
- Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University, Kyoto, Japan
| | - Kengo Kora
- Department of Pediatrics, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Taisei Kayaki
- Department of Pediatrics, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Kanako Maizuru
- Department of Pediatrics, Tenri Yorozu Hospital, Tenri, Japan
| | - Takahiro Hayashi
- Department of Pediatrics, Kurashiki Central Hospital, Kurashiki, Japan
| | - Atsushi Yokoyama
- Department of Pediatrics, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Masahiko Ajiro
- Division of Cancer RNA Research, National Cancer Center Research Institute, Tokyo, Japan
| | - Masatoshi Hagiwara
- Department of Drug Discovery Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan
- Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Teruyuki Kondo
- Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University, Kyoto, Japan
| | - Ryutaro Kira
- Department of Pediatric Neurology, Fukuoka Children's Hospital, Fukuoka, Japan
| | - Junko Takita
- Department of Pediatrics, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Takeshi Yoshida
- Department of Pediatrics, Kyoto University Graduate School of Medicine, Kyoto, Japan
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2
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Li H, Du X, Li X, Feng P, Chu M, Jin Y, Pan Z. Genetic diversity, tissue-specific expression, and functional analysis of the ATP7A gene in sheep. Front Genet 2023; 14:1239979. [PMID: 37799137 PMCID: PMC10547898 DOI: 10.3389/fgene.2023.1239979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Accepted: 09/06/2023] [Indexed: 10/07/2023] Open
Abstract
In humans, variation of the ATP7A gene may cause cranial exostosis, which is similar to "human horn," but the function of the ATP7A gene in sheep is still unknown. Tissue expression patterns and potential functional loci analysis of the ATP7A gene could help understand its function in sheep horn. In this study, we first identified tissue, sex, breed, and species-specific expression of the ATP7A gene in sheep based on the RNA-sequencing (RNA-seq) data. Second, the potential functional sites of the ATP7A gene were analyzed by using the whole genome sequencing (WGS) data of 99 sheep from 10 breeds. Last, the allele-specific expression of the ATP7A gene was explored. Our result showed the ATP7A gene has significantly higher expression in the big horn than in the small horn, and the ATP7A gene has high expression in the horn and skin, suggesting that this gene may be related to the horn. The PCA results show that the region around the ATP7A can distinguish horned and hornless groups to some extent, further indicating that the ATP7A may be related to horns. When compared with other species, we find seven ruminate specific amino acid sites of the ATP7A protein, which can be important to the ruminate horn. By analyzing WGS, we found 6 SNP sites with significant differences in frequency in horned and hornless populations, and most of these variants are present in the intron. But we still find some potential functional sites, including three missenses, three synonymous mutations, and four Indels. Finally, by combining the RNA-seq and WGS functional loci results, we find three mutations that showed allele-specific expression between big and small horns. This study shows that the ATP7A gene in sheep may be related to horn size, and several potential functional sites we identified here can be useful molecular markers for sheep horn breeding.
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Affiliation(s)
- Hao Li
- Engineering Research Center of North-East Cold Region Beef Cattle Science & Technology Innovation, Ministry of Education, College of Agriculture, Yanbian University, Yanji, China
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xiaolong Du
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xinyue Li
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Pingjie Feng
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Mingxing Chu
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yi Jin
- Engineering Research Center of North-East Cold Region Beef Cattle Science & Technology Innovation, Ministry of Education, College of Agriculture, Yanbian University, Yanji, China
| | - Zhangyuan Pan
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China
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3
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Salazar D, Kloke KM, Guerrero RB, Ferreira CR, Blau N. Clinical and biochemical footprints of inherited metabolic disorders. XI. Gastrointestinal symptoms. Mol Genet Metab 2023; 138:107528. [PMID: 36774919 PMCID: PMC10509718 DOI: 10.1016/j.ymgme.2023.107528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 01/28/2023] [Accepted: 01/29/2023] [Indexed: 02/04/2023]
Abstract
Inherited metabolic disorders presenting with gastrointestinal (GI) symptoms are characterized by the dysfunction of the esophagus, stomach, small and large intestines, and pancreas. We have summarized associations of signs and symptoms in 339 inherited metabolic diseases presenting with GI symptoms. Feeding difficulties represent the most common abnormality reported for IMDs with GI involvement (37%) followed by intestinal problems (30%), vomiting (22%), stomach and pancreas involvement (8% each), and esophagus involvement (4%). This represents the eleventh of a series of articles attempting to create and maintain a comprehensive list of clinical and metabolic differential diagnoses according to system involvement.
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Affiliation(s)
- Denise Salazar
- Quest Diagnostics Nichols Institute, San Juan Capistrano, CA, United States of America.
| | - Karen M Kloke
- Mayo Clinic Laboratories, Rochester, MN, United States of America.
| | | | - Carlos R Ferreira
- National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, United States of America.
| | - Nenad Blau
- Division of Metabolism, University Children's Hospital, Zürich, Switzerland.
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4
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Kaczmarek A, Kasprzyk M, Koch A, Szymanski A. Orthopaedic interventions in occipital horn syndrome: a rare case of mutation in ATP7A gene. EGYPTIAN JOURNAL OF MEDICAL HUMAN GENETICS 2022. [DOI: 10.1186/s43042-022-00235-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Occipital horn syndrome is a rare, X-linked recessive, connective tissue disorder caused by abnormal copper transporter proteins coded by the ATP7A gene. 32 cases have been reported worldwide to date. Clinically, patients typically present with inguinal hernia, exostosis, cutis laxa, and bladder diverticula. Orthopaedic problems often include exostosis of the elbows, thoracolumbar scoliosis, thoracic cavity deformities, and joint hypermobility due to joint laxity.
Case presentation
An 18-year-old presented with occipital horn syndrome and was treated for flat-valgus foot and posterior dislocation of the elbow joints. Due to collagen structure abnormalities, vulnerability to joint deformation makes treating patients with occipital horn syndrome challenging as they need complex orthopaedic intervention.
Conclusion
There is no effective causal therapy for this condition. Surgical procedures can help patients improve their physical condition and maintain adequate joint range of motion.
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5
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Bukowska-Olech E, Trzebiatowska W, Czech W, Drzymała O, Frąk P, Klarowski F, Kłusek P, Szwajkowska A, Jamsheer A. Hereditary Multiple Exostoses-A Review of the Molecular Background, Diagnostics, and Potential Therapeutic Strategies. Front Genet 2021; 12:759129. [PMID: 34956317 PMCID: PMC8704583 DOI: 10.3389/fgene.2021.759129] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2021] [Accepted: 11/08/2021] [Indexed: 11/17/2022] Open
Abstract
Hereditary multiple exostoses (HMEs) syndrome, also known as multiple osteochondromas, represents a rare and severe human skeletal disorder. The disease is characterized by multiple benign cartilage-capped bony outgrowths, termed exostoses or osteochondromas, that locate most commonly in the juxta-epiphyseal portions of long bones. Affected individuals usually complain of persistent pain caused by the pressure on neighboring tissues, disturbance of blood circulation, or rarely by spinal cord compression. However, the most severe complication of this condition is malignant transformation into chondrosarcoma, occurring in up to 3.9% of HMEs patients. The disease results mainly from heterozygous loss-of-function alterations in the EXT1 or EXT2 genes, encoding Golgi-associated glycosyltransferases, responsible for heparan sulfate biosynthesis. Some of the patients with HMEs do not carry pathogenic variants in those genes, hence the presence of somatic mutations, deep intronic variants, or another genes/loci is suggested. This review presents the systematic analysis of current cellular and molecular concepts of HMEs along with clinical characteristics, clinical and molecular diagnostic methods, differential diagnosis, and potential treatment options.
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Affiliation(s)
| | | | - Wiktor Czech
- Medical Student, Poznan University of Medical Sciences, Poznan, Poland
| | - Olga Drzymała
- Medical Student, Poznan University of Medical Sciences, Poznan, Poland
| | - Piotr Frąk
- Medical Student, Poznan University of Medical Sciences, Poznan, Poland
| | | | - Piotr Kłusek
- Medical Student, Poznan University of Medical Sciences, Poznan, Poland
| | - Anna Szwajkowska
- Medical Student, Poznan University of Medical Sciences, Poznan, Poland
| | - Aleksander Jamsheer
- Department of Medical Genetics, Poznan University of Medical Sciences, Poznan, Poland.,Centers for Medical Genetics GENESIS, Poznan, Poland
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6
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Beyens A, Pottie L, Sips P, Callewaert B. Clinical and Molecular Delineation of Cutis Laxa Syndromes: Paradigms for Homeostasis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1348:273-309. [PMID: 34807425 DOI: 10.1007/978-3-030-80614-9_13] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Cutis laxa (CL) syndromes are a large and heterogeneous group of rare connective tissue disorders that share loose redundant skin as a hallmark clinical feature, which reflects dermal elastic fiber fragmentation. Both acquired and congenital-Mendelian- forms exist. Acquired forms are progressive and often preceded by inflammatory triggers in the skin, but may show systemic elastolysis. Mendelian forms are often pleiotropic in nature and classified upon systemic manifestations and mode of inheritance. Though impaired elastogenesis is a common denominator in all Mendelian forms of CL, the underlying gene defects are diverse and affect structural components of the elastic fiber or impair metabolic pathways interfering with cellular trafficking, proline synthesis, or mitochondrial functioning. In this chapter we provide a detailed overview of the clinical and molecular characteristics of the different cutis laxa types and review the latest insights on elastic fiber assembly and homeostasis from both human and animal studies.
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Affiliation(s)
- Aude Beyens
- Center for Medical Genetics Ghent, Department of Dermatology, Department of Biomolecular Medicine, Ghent University Hospital, Ghent University, Ghent, Belgium
| | - Lore Pottie
- Center for Medical Genetics Ghent, Ghent University Hospital, Ghent, Belgium.,Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
| | - Patrick Sips
- Center for Medical Genetics Ghent, Ghent University Hospital, Ghent, Belgium.,Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
| | - Bert Callewaert
- Center for Medical Genetics Ghent, Department of Biomolecular Medicine, Ghent University Hospital, Ghent University, Ghent, Belgium.
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7
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Maung MT, Carlson A, Olea-Flores M, Elkhadragy L, Schachtschneider KM, Navarro-Tito N, Padilla-Benavides T. The molecular and cellular basis of copper dysregulation and its relationship with human pathologies. FASEB J 2021; 35:e21810. [PMID: 34390520 DOI: 10.1096/fj.202100273rr] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 06/23/2021] [Accepted: 07/07/2021] [Indexed: 12/16/2022]
Abstract
Copper (Cu) is an essential micronutrient required for the activity of redox-active enzymes involved in critical metabolic reactions, signaling pathways, and biological functions. Transporters and chaperones control Cu ion levels and bioavailability to ensure proper subcellular and systemic Cu distribution. Intensive research has focused on understanding how mammalian cells maintain Cu homeostasis, and how molecular signals coordinate Cu acquisition and storage within organs. In humans, mutations of genes that regulate Cu homeostasis or facilitate interactions with Cu ions lead to numerous pathologic conditions. Malfunctions of the Cu+ -transporting ATPases ATP7A and ATP7B cause Menkes disease and Wilson disease, respectively. Additionally, defects in the mitochondrial and cellular distributions and homeostasis of Cu lead to severe neurodegenerative conditions, mitochondrial myopathies, and metabolic diseases. Cu has a dual nature in carcinogenesis as a promotor of tumor growth and an inducer of redox stress in cancer cells. Cu also plays role in cancer treatment as a component of drugs and a regulator of drug sensitivity and uptake. In this review, we provide an overview of the current knowledge of Cu metabolism and transport and its relation to various human pathologies.
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Affiliation(s)
- May T Maung
- Department of Molecular Biology and Biochemistry, Wesleyan University, Middletown, CT, USA
| | - Alyssa Carlson
- Department of Molecular Biology and Biochemistry, Wesleyan University, Middletown, CT, USA
| | - Monserrat Olea-Flores
- Facultad de Ciencias Químico Biológicas, Universidad Autónoma de Guerrero, Guerrero, Mexico
| | - Lobna Elkhadragy
- Department of Radiology, University of Illinois at Chicago, Chicago, IL, USA
| | - Kyle M Schachtschneider
- Department of Radiology, University of Illinois at Chicago, Chicago, IL, USA.,Department of Biochemistry & Molecular Genetics, University of Illinois at Chicago, Chicago, IL, USA.,National Center for Supercomputing Applications, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Napoleon Navarro-Tito
- Facultad de Ciencias Químico Biológicas, Universidad Autónoma de Guerrero, Guerrero, Mexico
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8
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Adeva-Andany MM, Adeva-Contreras L, Fernández-Fernández C, González-Lucán M, Funcasta-Calderón R. Elastic tissue disruption is a major pathogenic factor to human vascular disease. Mol Biol Rep 2021; 48:4865-4878. [PMID: 34129188 DOI: 10.1007/s11033-021-06478-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Accepted: 06/05/2021] [Indexed: 01/15/2023]
Abstract
Elastic fibers are essential components of the arterial extracellular matrix. They consist of the protein elastin and an array of microfibrils that support the protein and connect it to the surrounding matrix. The elastin gene encodes tropoelastin, a protein that requires extensive cross-linking to become elastin. Tropoelastin is expressed throughout human life, but its expression levels decrease with age, suggesting that the potential to synthesize elastin persists during lifetime although declines with aging. The initial abnormality documented in human atherosclerosis is fragmentation and loss of the elastic network in the medial layer of the arterial wall, suggesting an imbalance between elastic fiber injury and restoration. Damaged elastic structures are not adequately repaired by synthesis of new elastic elements. Progressive collagen accumulation follows medial elastic fiber disruption and fibrous plaques are formed, but advanced atherosclerosis lesions do not develop in the absence of prior elastic injury. Aging is associated with arterial extracellular matrix anomalies that evoke those present in early atherosclerosis. The reduction of elastic fibers with subsequent collagen accumulation leads to arterial stiffening and intima-media thickening, which are independent predictors of incident hypertension in prospective community-based studies. Arterial stiffening precedes the development of hypertension. The fundamental role of the vascular elastic network to arterial structure and function is emphasized by congenital disorders caused by mutations that disrupt normal elastic fiber production. Molecular changes in the genes coding tropoelastin, lysyl oxidase (tropoelastin cross-linking), and elastin-associated microfibrils, including fibrillin-1, fibulin-4, and fibulin-5 produce severe vascular injury due to absence of functional elastin.
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Affiliation(s)
- María M Adeva-Andany
- Nephrology Division, Internal Medicine Department, Hospital General Juan Cardona, c/ Pardo Bazán s/n, 15406, Ferrol, Spain.
| | | | - Carlos Fernández-Fernández
- Nephrology Division, Internal Medicine Department, Hospital General Juan Cardona, c/ Pardo Bazán s/n, 15406, Ferrol, Spain
| | - Manuel González-Lucán
- Nephrology Division, Internal Medicine Department, Hospital General Juan Cardona, c/ Pardo Bazán s/n, 15406, Ferrol, Spain
| | - Raquel Funcasta-Calderón
- Nephrology Division, Internal Medicine Department, Hospital General Juan Cardona, c/ Pardo Bazán s/n, 15406, Ferrol, Spain
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9
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Copper Toxicity Associated With an ATP7A-Related Complex Phenotype. Pediatr Neurol 2021; 119:40-44. [PMID: 33894639 DOI: 10.1016/j.pediatrneurol.2021.03.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 03/14/2021] [Accepted: 03/17/2021] [Indexed: 11/21/2022]
Abstract
BACKGROUND The ATP7A gene encodes a copper transporter whose mutations cause Menkes disease, occipital horn syndrome (OHS), and, less frequently, ATP7A-related distal hereditary motor neuropathy (dHMN). Here we describe a family with OHS caused by a novel mutation in the ATP7A gene, including a patient with a comorbid dHMN that worsened markedly after being treated with copper histidinate. METHODS We studied in detail the clinical features of the patients and performed a genomic analysis by using TruSight One Expanded Sequencing Panel. Subsequently, we determined the ATP7A and ATP7B expression levels, mitochondrial membrane potential, and redox balance in cultured fibroblasts of Patient 1. RESULTS We found a novel ATP7A late truncated mutation p.Lys1412AsnfsX15 in the two affected members of this family. The co-occurrence of OHS and dHMN in Patient 1 reveals the variable phenotypic expressivity of the variant. A severe clinical and neurophysiologic worsening was observed in the dHMN of Patient 1 when he was treated with copper replacement therapy, with a subsequent fast recovery after the copper histidinate was withdrawn. Functional studies revealed that the patient had low levels of both ATP7A and ATP7B, the other copper transporter, and high levels of superoxide ion in the mitochondria. CONCLUSIONS Our findings broaden the clinical spectrum of ATP7A-related disorders and demonstrate that two clinical phenotypes can occur in the same patient. The copper-induced toxicity and low levels of both ATP7A and ATP7B in our patient suggest that copper accumulation in motor neurons is the pathogenic mechanism in ATP7A-related dHMN.
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10
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McKenzie F, Mina K, Callewaert B, Beyens A, Dickinson JE, Jevon G, Papadimitriou J, Diness BR, Steensberg JN, Ek J, Baynam G. Severe congenital cutis laxa: Identification of novel homozygous LOX gene variants in two families. Clin Genet 2021; 100:168-175. [PMID: 33866545 DOI: 10.1111/cge.13969] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Revised: 04/12/2021] [Accepted: 04/15/2021] [Indexed: 11/28/2022]
Abstract
We report three babies from two families with a severe lethal form of congenital cutis laxa. All three had redundant and doughy-textured skin and two siblings from one family had facial dysmorphism. Echocardiograms showed thickened and poorly contractile hearts, arterial dilatation and tortuosity. Post-mortem examination in two of the babies further revealed widespread ectasia and tortuosity of medium and large sized arteries, myocardial hypertrophy, rib and skull fractures. The presence of fractures initially suggested a diagnosis of osteogenesis imperfecta. Under light microscopy bony matrices were abnormal and arterial wall architecture was grossly abnormal showing fragmented elastic fibres. Molecular analysis of known cutis laxa genes did not yield any pathogenic defects. Whole exome sequencing of DNA following informed consent identified two separate homozygous variants in the LOX (Lysyl Oxidase) gene. LOX belongs to the 5-lysyl oxidase gene family involved in initiation of cross-linking of elastin and collagen. A mouse model of a different variant in this gene recapitulates the phenotype seen in the three babies. Our findings suggest that the LOX gene is a novel cause of severe congenital cutis laxa with arterial tortuosity, bone fragility and respiratory failure.
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Affiliation(s)
- Fiona McKenzie
- Genetic Services of Western Australia, King Edward Memorial Hospital, Perth, Western Australia, Australia.,School of Paediatrics and Child Health, University of Western Australia, Perth, Western Australia, Australia
| | - Kym Mina
- Department of Diagnostic Genomics, PathWest, Perth, Western Australia, Australia
| | - Bert Callewaert
- Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium.,Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
| | - Aude Beyens
- Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium.,Department of Biomolecular Medicine, Ghent University, Ghent, Belgium.,Department of Dermatology, Ghent University Hospital, Ghent, Belgium
| | - Jan E Dickinson
- Maternal Fetal Medicine Service, King Edward Memorial Hospital, Perth, Western Australia, Australia.,Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia
| | - Gareth Jevon
- Department of Paediatric Pathology, PathWest, Perth Children's Hospital, Perth, Western Australia, Australia
| | - John Papadimitriou
- Centre for Orthopaedic Translational Research, Medical School, University of Western Australia, Nedlands, Western Australia, Australia.,Pathwest Laboratories, Perth, Western Australia, Australia
| | - Birgitte Rode Diness
- Department of Clinical Genetics, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark.,Department of Clinical Medicine, Copenhagen University, Copenhagen, Denmark
| | | | - Jakob Ek
- Department of Clinical Genetics, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| | - Gareth Baynam
- Genetic Services of Western Australia, King Edward Memorial Hospital, Perth, Western Australia, Australia.,The Western Australia Register of Developmental Anomalies, Department of Health, Government of Western Australia, Perth, Western Australia, Australia.,School of Medicine, Division of Paediatrics and Telethon Kids Institute, University of Western Australia, Perth, Western Australia, Australia
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11
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Møller LB, Mogensen M, Weaver DD, Pedersen PA. Occipital Horn Syndrome as a Result of Splice Site Mutations in ATP7A. No Activity of ATP7A Splice Variants Missing Exon 10 or Exon 15. Front Mol Neurosci 2021; 14:532291. [PMID: 33967692 PMCID: PMC8097048 DOI: 10.3389/fnmol.2021.532291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 03/12/2021] [Indexed: 11/13/2022] Open
Abstract
Disease-causing variants in ATP7A lead to two different phenotypes associated with copper deficiency; a lethal form called Menkes disease (MD), leading to early death, and a much milder form called occipital horn syndrome (OHS). Some investigators have proposed that an ATP7A transcript missing exon 10 leads to a partly active protein product resulting in the OHS phenotype. Here, we describe an individual with OHS, a biology professor, who survived until age 62 despite a splice site mutation, leading to skipping of exon 15. ATP7A transcripts missing exon 10, or exon 15 preserve the reading frame, but it is unknown if either of these alternative transcripts encode functional protein variants. We have investigated the molecular consequence of splice site mutations leading to skipping of exon 10 or exon 15 which have been identified in individuals with OHS, or MD. By comparing ATP7A expression in fibroblasts from three individuals with OHS (OHS-fibroblasts) to ATP7A expression in fibroblasts from two individuals with MD (MD-fibroblasts), we demonstrate that transcripts missing either exon 10 or exon 15 were present in similar amounts in OHS-fibroblasts and MD-fibroblasts. No ATP7A protein encoded from these transcripts could be detected in the OHS and MD fibroblast. These results, combined with the observation that constructs encoding ATP7A cDNA sequences missing either exon 10, or exon 15 were unable to complement the high iron requirement of the ccc2Δ yeast strain, provide evidence that neither a transcript missing exon 10 nor a transcript missing exon 15 results in functional ATP7A protein. In contrast, higher amounts of wild-type ATP7A transcript were present in the OHS-fibroblasts compared with the MD-fibroblasts. We found that the MD-fibroblasts contained between 0 and 0.5% of wild-type ATP7A transcript, whereas the OHS-fibroblasts contained between 3 and 5% wild-type transcripts compared with the control fibroblasts. In summary these results indicate that protein variants encoded by ATP7A transcripts missing either exon 10 or exon 15 are not functional and not responsible for the OHS phenotype. In contrast, expression of only 3-5% of wild-type transcript compared with the controls permits the OHS phenotype.
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Affiliation(s)
- Lisbeth Birk Møller
- Department of Clinical Genetics, Applied Human Molecular Genetics, Kennedy Center, Copenhagen University Hospital, Glostrup, Denmark
| | - Mie Mogensen
- Department of Clinical Genetics, Applied Human Molecular Genetics, Kennedy Center, Copenhagen University Hospital, Glostrup, Denmark
| | - David D Weaver
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN, United States
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Boel A, Veszelyi K, Németh CE, Beyens A, Willaert A, Coucke P, Callewaert B, Margittai É. Arterial Tortuosity Syndrome: An Ascorbate Compartmentalization Disorder? Antioxid Redox Signal 2021; 34:875-889. [PMID: 31621376 DOI: 10.1089/ars.2019.7843] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Significance: Cardiovascular disorders are the most important cause of morbidity and mortality in the Western world. Monogenic developmental disorders of the heart and vessels are highly valuable to study the physiological and pathological processes in cardiovascular system homeostasis. The arterial tortuosity syndrome (ATS) is a rare, autosomal recessive connective tissue disorder showing lengthening, tortuosity, and stenosis of the large arteries, with a propensity for aneurysm formation. In histopathology, it associates with fragmentation and disorganization of elastic fibers in several tissues, including the arterial wall. ATS is caused by pathogenic variants in SLC2A10 encoding the facilitative glucose transporter (GLUT)10. Critical Issues: Although several hypotheses have been forwarded, the molecular mechanisms linking disrupted GLUT10 activity with arterial malformations are largely unknown. Recent Advances: The vascular and systemic manifestations and natural history of ATS patients have been largely delineated. GLUT10 was identified as an intracellular transporter of dehydroascorbic acid, which contributes to collagen and elastin cross-linking in the endoplasmic reticulum, redox homeostasis in the mitochondria, and global and gene-specific methylation/hydroxymethylation affecting epigenetic regulation in the nucleus. We revise here the current knowledge on ATS and the role of GLUT10 within the compartmentalization of ascorbate in physiological and diseased states. Future Directions: Centralization of clinical, treatment, and outcome data will enable better management for ATS patients. Establishment of representative animal disease models could facilitate the study of pathomechanisms underlying ATS. This might be relevant for other forms of vascular dysplasia, such as isolated aneurysm formation, hypertensive vasculopathy, and neovascularization. Antioxid. Redox Signal. 34, 875-889.
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Affiliation(s)
- Annekatrien Boel
- Department of Biomolecular Medicine, Center for Medical Genetics Ghent, Ghent University, Ghent, Belgium
| | - Krisztina Veszelyi
- Institute of Clinical Experimental Research, Molecular Biology, and Pathobiochemistry, Semmelweis University, Budapest, Hungary
| | - Csilla E Németh
- Department of Medical Chemistry, Molecular Biology, and Pathobiochemistry, Semmelweis University, Budapest, Hungary
| | - Aude Beyens
- Department of Biomolecular Medicine, Center for Medical Genetics Ghent, Ghent University, Ghent, Belgium
| | - Andy Willaert
- Department of Biomolecular Medicine, Center for Medical Genetics Ghent, Ghent University, Ghent, Belgium
| | - Paul Coucke
- Department of Biomolecular Medicine, Center for Medical Genetics Ghent, Ghent University, Ghent, Belgium
| | - Bert Callewaert
- Department of Biomolecular Medicine, Center for Medical Genetics Ghent, Ghent University, Ghent, Belgium
| | - Éva Margittai
- Institute of Clinical Experimental Research, Molecular Biology, and Pathobiochemistry, Semmelweis University, Budapest, Hungary
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13
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Mandia D, Shor N, Benoist JF, Nadjar Y. Adolescent-Onset and Adult-Onset Vitamin-Responsive Neurogenetic Diseases: A Review. JAMA Neurol 2021; 78:483-490. [PMID: 33427863 DOI: 10.1001/jamaneurol.2020.4911] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Importance Vitamin-responsive inherited diseases are among the rare genetic disorders with a specific pharmacological treatment. Many of these conditions have a prominent neurological phenotype that is mainly reported in children. Being rare and often strikingly different in adult-onset forms, they are still poorly known in the medical fields specific to adults. Observation This article reviews all articles reporting cases of patients with a genetically confirmed inherited vitamin-responsive neurological disease and neurological onset after the age of 10 years. On this basis, 24 different diseases are described, involving vitamins A, B1, B2, B3, B6, B8, B9, B12, E, and tetrahydrobiopterin (BH4). Information such as clinical symptoms, disease course, imaging studies, biochemical alterations, and response to treatment present an overall picture of these patients. Conclusions and Relevance Vitamin-responsive neurogenetic diseases represent a group of rare conditions that are probably underdiagnosed in adults and may have a dramatic response to treatment when started early in the course of the disease. In this review, main features of the adult-onset forms are defined and simple key messages are provided to help identify clinical situations when specific diagnostic tests should be performed and/or vitamins should be promptly administered.
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Affiliation(s)
- Daniele Mandia
- Neuro-Metabolism Unit, Reference Center for Lysosomal Diseases, Neurology Department, Hôpital Pitié-Salpêtrière, Paris, France
| | - Natalia Shor
- Department of Neuroradiology, Pitié-Salpêtrière Hospital, Paris, France.,Sorbonne University, Paris VI University, Paris, France
| | - Jean-François Benoist
- Metabolic Biochemistry Laboratory, Necker Enfants Malades University Hospital, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Yann Nadjar
- Neuro-Metabolism Unit, Reference Center for Lysosomal Diseases, Neurology Department, Hôpital Pitié-Salpêtrière, Paris, France
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14
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Merico V, Imberti JF, Zanoni M, Boriani G, Garagna S, Imberti R. Inhibition of lysyl oxidase stimulates TGF-β signaling and metalloproteinases-2 and -9 expression and contributes to the disruption of ascending aorta in rats: protection by propylthiouracil. Heart Vessels 2021; 36:738-747. [PMID: 33462684 DOI: 10.1007/s00380-020-01750-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 12/04/2020] [Indexed: 10/22/2022]
Abstract
Mutations in lysyl oxidase (LOX) genes cause severe vascular anomalies in mice and humans. LOX activity can be irreversibly inhibited by the administration of β-aminoproprionitrile (BAPN). We investigated the mechanisms underlying the damage to the ascending thoracic aorta induced by LOX deficiency and evaluated whether 6-propylthiouracil (PTU) can afford protection in rats. BAPN administration caused disruption of the ascending aortic wall, increased the number of apoptotic cells, stimulated TGF-β signaling (increase of nuclear p-SMAD2 staining), and up-regulated the expression of metalloproteinases-2 and -9. In BAPN-treated animals, PTU reduced apoptosis, p-SMAD2 staining, MMP-2, and -9 expression, and markedly decreased the damage to the aortic wall. Our results suggest that, as in some heritable vascular diseases, enhanced TGF-β signaling and upregulation of MMP-2 and -9 can contribute to the pathogenesis of ascending aorta damage caused by LOX deficiency. We have also shown that PTU, a drug already in clinical use, protects against the effects of LOX inhibition. MMP-2 and -9 might be potential targets of new therapeutic strategies for the treatment of vascular diseases caused by LOX deficiency.
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Affiliation(s)
- Valeria Merico
- Dipartimento di Biologia e Biotecnologie "Lazzaro Spallanzani", University of Pavia, Pavia, Italy
| | - Jacopo Francesco Imberti
- Division of Cardiology, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Policlinico di Modena, Modena, Italy
| | - Mario Zanoni
- Dipartimento di Biologia e Biotecnologie "Lazzaro Spallanzani", University of Pavia, Pavia, Italy
| | - Giuseppe Boriani
- Division of Cardiology, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Policlinico di Modena, Modena, Italy
| | - Silvia Garagna
- Dipartimento di Biologia e Biotecnologie "Lazzaro Spallanzani", University of Pavia, Pavia, Italy.,Centre for Health Technologies (C.H.T.), University of Pavia, Pavia, Italy
| | - Roberto Imberti
- Phase I Clinical Trials Unit and Experimental Therapy, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy.
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15
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Beyens A, Boel A, Symoens S, Callewaert B. Cutis laxa: A comprehensive overview of clinical characteristics and pathophysiology. Clin Genet 2020; 99:53-66. [PMID: 33058140 DOI: 10.1111/cge.13865] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 09/17/2020] [Accepted: 10/07/2020] [Indexed: 12/20/2022]
Abstract
Cutis laxa (CL) syndromes comprise a rare group of multisystem disorders that share loose redundant skin folds as hallmark clinical feature. CL results from impaired elastic fiber assembly and homeostasis, and the known underlying gene defects affect different extracellular matrix proteins, intracellular trafficking, or cellular metabolism. Due to the underlying clinical and molecular heterogeneity, the diagnostic work-up of CL patients is often challenging. In this review, we provide a practical approach to the broad differential diagnosis of CL syndromes, provide an overview of the molecular pathogenesis of the different subtypes, and suggest general management guidelines.
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Affiliation(s)
- Aude Beyens
- Center for Medical Genetics Ghent, Ghent University Hospital, Ghent, Belgium.,Department of Dermatology, Ghent University Hospital, Ghent, Belgium.,Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
| | - Annekatrien Boel
- Center for Medical Genetics Ghent, Ghent University Hospital, Ghent, Belgium.,Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
| | - Sofie Symoens
- Center for Medical Genetics Ghent, Ghent University Hospital, Ghent, Belgium.,Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
| | - Bert Callewaert
- Center for Medical Genetics Ghent, Ghent University Hospital, Ghent, Belgium.,Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
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Mhaske A, Dileep K, Kumar M, Poojary M, Pandhare K, Zhang KY, Scaria V, Binukumar B. ATP7A Clinical Genetics Resource - A comprehensive clinically annotated database and resource for genetic variants in ATP7A gene. Comput Struct Biotechnol J 2020; 18:2347-2356. [PMID: 32994893 PMCID: PMC7501406 DOI: 10.1016/j.csbj.2020.08.021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 08/25/2020] [Accepted: 08/26/2020] [Indexed: 12/21/2022] Open
Abstract
ATP7A is a critical copper transporter involved in Menkes Disease, Occipital horn Syndrome and X-linked distal spinal muscular atrophy type 3 which are X linked genetic disorders. These are rare diseases and their genetic epidemiology of the diseases is unknown. A number of genetic variants in the genes have been reported in published literature as well as databases, however, understanding the pathogenicity of variants and genetic epidemiology requires the data to be compiled in a unified format. To this end, we systematically compiled genetic variants from published literature and datasets. Each of the variants were systematically evaluated for evidences with respect to their pathogenicity and classified as per the American College of Medical Genetics and the Association of Molecular Pathologists (ACMG-AMP) guidelines into Pathogenic, Likely Pathogenic, Benign, Likely Benign and Variants of Uncertain Significance. Additional integrative analysis of population genomic datasets provides insights into the genetic epidemiology of the disease through estimation of carrier frequencies in global populations. To deliver a mechanistic explanation for the pathogenicity of selected variants, we also performed molecular modeling studies. Our modeling studies concluded that the small structural distortions observed in the local structures of the protein may lead to the destabilization of the global structure. To the best of our knowledge, ATP7A Clinical Genetics Resource is one of the most comprehensive compendium of variants in the gene providing clinically relevant annotations in gene.
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Affiliation(s)
- Aditi Mhaske
- CSIR Institute of Genomics and Integrative Biology, Mathura Road, Delhi 110 025, India
| | - K.V. Dileep
- Laboratory for Structural Bioinformatics, Center for Biosystems Dynamics Research, RIKEN, 1-7-22 Suehiro, Tsurumi, Yokohama, Kanagawa 230-0045, Japan
| | - Mukesh Kumar
- CSIR Institute of Genomics and Integrative Biology, Mathura Road, Delhi 110 025, India
- Academy of Scientific and Innovative Research, CSIR-IGIB South Campus, Mathura Road, Delhi, India
| | - Mukta Poojary
- CSIR Institute of Genomics and Integrative Biology, Mathura Road, Delhi 110 025, India
- Academy of Scientific and Innovative Research, CSIR-IGIB South Campus, Mathura Road, Delhi, India
| | - Kavita Pandhare
- CSIR Institute of Genomics and Integrative Biology, Mathura Road, Delhi 110 025, India
- Academy of Scientific and Innovative Research, CSIR-IGIB South Campus, Mathura Road, Delhi, India
| | - Kam Y.J. Zhang
- Laboratory for Structural Bioinformatics, Center for Biosystems Dynamics Research, RIKEN, 1-7-22 Suehiro, Tsurumi, Yokohama, Kanagawa 230-0045, Japan
| | - Vinod Scaria
- CSIR Institute of Genomics and Integrative Biology, Mathura Road, Delhi 110 025, India
- Academy of Scientific and Innovative Research, CSIR-IGIB South Campus, Mathura Road, Delhi, India
- Corresponding author at: CSIR-Institute of Genomics and Integrative Biology (IGIB), Mathura Road, Sukhdev Vihar, New Delhi 110025, India.
| | - B.K. Binukumar
- CSIR Institute of Genomics and Integrative Biology, Mathura Road, Delhi 110 025, India
- Academy of Scientific and Innovative Research, CSIR-IGIB South Campus, Mathura Road, Delhi, India
- Corresponding author at: CSIR-Institute of Genomics and Integrative Biology (IGIB), Mathura Road, Sukhdev Vihar, New Delhi 110025, India.
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Ritelli M, Colombi M. Molecular Genetics and Pathogenesis of Ehlers-Danlos Syndrome and Related Connective Tissue Disorders. Genes (Basel) 2020; 11:genes11050547. [PMID: 32414079 PMCID: PMC7288446 DOI: 10.3390/genes11050547] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 05/11/2020] [Indexed: 12/21/2022] Open
Abstract
Ehlers–Danlos syndromes (EDS) are a group of heritable connective tissue disorders (HCTDs) characterized by a variable degree of skin hyperextensibility, joint hypermobility and tissue fragility. The current EDS classification distinguishes 13 subtypes and 19 different causal genes mainly involved in collagen and extracellular matrix synthesis and maintenance. EDS need to be differentiated from other HCTDs with a variable clinical overlap including Marfan syndrome and related disorders, some types of skeletal dysplasia and cutis laxa. Clinical recognition of EDS is not always straightforward and for a definite diagnosis, molecular testing can be of great assistance, especially in patients with an uncertain phenotype. Currently, the major challenging task in EDS is to unravel the molecular basis of the hypermobile EDS that is the most frequent form, and for which the diagnosis is only clinical in the absence of any definite laboratory test. This EDS subtype, as well as other EDS-reminiscent phenotypes, are currently investigated worldwide to unravel the primary genetic defect and related pathomechanisms. The research articles, case report, and reviews published in this Special Issue focus on different clinical, genetic and molecular aspects of several EDS subtypes and some related disorders, offering novel findings and future research and nosological perspectives.
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