1
|
Kiener S, Åhman S, Cikota R, Jagannathan V, Blatter S, Cvitas I, Soto S, Leeb T. Heterozygous ASPRV1 frameshift variant in a Pembroke Welsh Corgi with ichthyosis. Anim Genet 2024; 55:490-492. [PMID: 38549226 DOI: 10.1111/age.13423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Accepted: 03/18/2024] [Indexed: 05/04/2024]
Affiliation(s)
- Sarah Kiener
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern, Switzerland
- Dermfocus, University of Bern, Bern, Switzerland
| | | | | | - Vidhya Jagannathan
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Sohvi Blatter
- Institute of Animal Pathology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Iva Cvitas
- Institute of Animal Pathology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Sara Soto
- Institute of Animal Pathology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Tosso Leeb
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern, Switzerland
- Dermfocus, University of Bern, Bern, Switzerland
| |
Collapse
|
2
|
Meyer JM, Boeglin WE, Brash AR. Recombinant PNPLA1 catalyzes the synthesis of acylceramides and acyl acids with selective incorporation of linoleic acid. J Lipid Res 2023; 64:100379. [PMID: 37087101 PMCID: PMC10209018 DOI: 10.1016/j.jlr.2023.100379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 04/17/2023] [Accepted: 04/18/2023] [Indexed: 04/24/2023] Open
Abstract
Loss-of-function mutations in patatin-like phospholipase domain-containing protein 1 (PNPLA1) cause autosomal recessive congenital ichthyosis, and altered PNPLA1 activity is implicated in the pathogenesis of atopic dermatitis and other common skin diseases. To examine the hypothesis that PNPLA1 catalyzes the synthesis of acylceramides and acyl acids, we expressed and partially purified a soluble, truncated form of PNPLA1 in Escherichia coli, (PNPLA1trun) along with the related protein PNPLA2 (ATGL, adipose triglyceride lipase) and coactivator CGI-58. Liposomal substrates were incubated with recombinant enzymes for 0.5-24 h and products analyzed by HPLC-UV and LC-MS. Using trilinolein or dilinolein substrates, PNPLA1trun, like ATGLtrun, catalyzed lipolysis and acyltransferase reactions with 2-30% conversion into linoleic acid, monolinolein, and trilinolein. CGI-58 enhanced ATGL-catalyzed lipolysis as previously reported, but transacylase activity was not enhanced with ATGL or PNPLA1. In matching the proposed activity in vivo, PNPLA1 catalyzed acyl transfer from trilinolein and dilinolein donors to omega-hydroxy ceramide, omega-hydroxy glucosylceramide, and omega-hydroxy acid acceptors to form acylceramide, glucosyl-acylceramide, and acyl acid, respectively, albeit with only ∼0.05% conversion of the substrates. Notably, in experiments comparing dilinolein vs. diolein acyl donors, PNPLA1 transferred linoleate with 3:1 selectivity over oleate into acylceramide. These results support the role for PNPLA1 in the synthesis of acylceramides and acyl acids in epidermis and suggest that the enrichment of these lipids with linoleic acid could result from the substrate selectivity of PNPLA1.
Collapse
Affiliation(s)
- Jason M Meyer
- Department of Dermatology, Vanderbilt University Medical Center, Nashville, TN, USA; Dermatology Service, Department of Veterans Affairs, Tennessee Valley Healthcare System, Nashville, TN, USA.
| | - William E Boeglin
- Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
| | - Alan R Brash
- Department of Pharmacology, Vanderbilt University, Nashville, TN, USA.
| |
Collapse
|
3
|
Kiener S, Castilla E, Jagannathan V, Welle M, Leeb T. SDR9C7
missense variant in a Chihuahua with non‐epidermolytic ichthyosis. Anim Genet 2023. [DOI: 10.1111/age.13319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 02/24/2023] [Accepted: 03/10/2023] [Indexed: 03/29/2023]
|
4
|
Affolter VK, Kiener S, Jagannathan V, Nagle T, Leeb T. A de novo variant in the keratin 1 gene (KRT1) in a Chinese shar-pei dog with severe congenital cornification disorder and non-epidermolytic ichthyosis. PLoS One 2022; 17:e0275367. [PMID: 36251712 PMCID: PMC9576078 DOI: 10.1371/journal.pone.0275367] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 09/15/2022] [Indexed: 11/05/2022] Open
Abstract
A 3-months old Chinese shar-pei puppy with ichthyosis was investigated. The dog showed generalized scaling, alopecia and footpad lesions. Histopathological examinations demonstrated a non-epidermolytic hyperkeratosis. The parents of the affected puppy did not show any skin lesions. A trio whole genome sequencing analysis identified a heterozygous de novo 3 bp deletion in the KRT1 gene in the affected dog. This variant, NM_001003392.1:c.567_569del, is predicted to delete a single asparagine from the conserved coil 1A motif within the rod domain of KRT1, NP_001003392.1:p.(Asn190del). Immunohistochemistry demonstrated normal levels of KRT1 expression in the epidermis and follicular epithelia. This might indicate that the variant possibly interferes with keratin dimerization or another function of KRT1. Missense variants affecting the homologous asparagine residue of the human KRT1 cause epidermolytic hyperkeratosis. Histologically, the investigated Chinese shar-pei showed a non-epidermolytic ichthyosis. The finding of a de novo variant in an excellent functional candidate gene strongly suggests that KRT1:p.Asn190del caused the ichthyosis phenotype in the affected Chinese shar-pei. To the best of our knowledge, this is the first description of a KRT1-related non-epidermolytic ichthyosis in domestic animals.
Collapse
Affiliation(s)
- Verena K. Affolter
- Department of Pathology, Microbiology, Immunology, School of Veterinary Medicine, University California Davis, Davis, California, United States of America
- * E-mail:
| | - Sarah Kiener
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern, Switzerland
- DermFocus, University of Bern, Bern, Switzerland
| | - Vidhya Jagannathan
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern, Switzerland
- DermFocus, University of Bern, Bern, Switzerland
| | - Terry Nagle
- Sacdermvet at Vista Veterinary Specialists, Sacramento, CA, United States of America
| | - Tosso Leeb
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern, Switzerland
- DermFocus, University of Bern, Bern, Switzerland
| |
Collapse
|
5
|
Inheritance of Monogenic Hereditary Skin Disease and Related Canine Breeds. Vet Sci 2022; 9:vetsci9080433. [PMID: 36006348 PMCID: PMC9412528 DOI: 10.3390/vetsci9080433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 07/20/2022] [Accepted: 08/12/2022] [Indexed: 11/17/2022] Open
Abstract
The plasticity of the genome is an evolutionary factor in all animal species, including canines, but it can also be the origin of diseases caused by hereditary genetic mutation. Genetic changes, or mutations, that give rise to a pathology in most cases result from recessive alleles that are normally found with minority allelic frequency. The use of genetic improvement increases the consanguinity within canine breeds and, on many occasions, also increases the frequency of these recessive alleles, increasing the prevalence of these pathologies. This prevalence has been known for a long time, but mutations differ according to the canine breed. These genetic diseases, including skin diseases, or genodermatosis, which is narrowly defined as monogenic hereditary dermatosis. In this review, we focus on genodermatosis sensu estricto, i.e., monogenic, and hereditary dermatosis, in addition to the clinical features, diagnosis, pathogeny, and treatment. Specifically, this review analyzes epidermolytic and non-epidermolytic ichthyosis, junctional epidermolysis bullosa, nasal parakeratosis, mucinosis, dermoid sinus, among others, in canine breeds, such as Golden Retriever, German Pointer, Australian Shepherd, American Bulldog, Great Dane, Jack Russell Terrier, Labrador Retriever, Shar-Pei, and Rhodesian Ridgeback.
Collapse
|
6
|
Kiener S, Chevallier L, Jagannathan V, Briand A, Cochet-Faivre N, Reyes-Gomez E, Leeb T. A COL5A2 In-Frame Deletion in a Chihuahua with Ehlers-Danlos Syndrome. Genes (Basel) 2022; 13:genes13050934. [PMID: 35627319 PMCID: PMC9142074 DOI: 10.3390/genes13050934] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 05/19/2022] [Accepted: 05/19/2022] [Indexed: 12/02/2022] Open
Abstract
Ehlers-Danlos syndrome (EDS) is a group of heterogeneous, rare diseases affecting the connective tissues. The main clinical signs of EDS are skin hyperextensibility, joint hypermobility, and skin fragility. Currently, the classification of EDS in humans distinguishes 13 clinical subtypes associated with variants in 20 different genes, reflecting the heterogeneity of this set of diseases. At present, variants in three of these genes have also been identified in dogs affected by EDS. The purpose of this study was to characterize the clinical and histopathological phenotype of an EDS-affected Chihuahua and to identify the causative genetic variant for the disease. The clinical examination suggested a diagnosis of classical EDS. Skin histopathology revealed an abnormally thin dermis, which is compatible with classical EDS. Whole-genome sequencing identified a heterozygous de novo 27 bp deletion in the COL5A2 gene, COL5A2:c.3388_3414del. The in-frame deletion is predicted to remove 9 amino acids in the triple-helical region of COL5A2. The molecular analysis and identification of a likely pathogenic variant in COL5A2 confirmed the subtype as a form of classical EDS. This is the first report of a COL5A2-related EDS in a dog.
Collapse
Affiliation(s)
- Sarah Kiener
- Institute of Genetics, Vetsuisse Faculty, University of Bern, 3001 Bern, Switzerland; (S.K.); (V.J.)
- Dermfocus, University of Bern, 3001 Bern, Switzerland
| | - Lucie Chevallier
- “Biology of the Neuromuscular System” Team, INSERM, IMRB, Univ Paris-Est Créteil, Ecole Nationale Vétérinaire d’Alfort, 94700 Maisons-Alfort, France; (L.C.); (E.R.-G.)
| | - Vidhya Jagannathan
- Institute of Genetics, Vetsuisse Faculty, University of Bern, 3001 Bern, Switzerland; (S.K.); (V.J.)
- Dermfocus, University of Bern, 3001 Bern, Switzerland
| | - Amaury Briand
- Unité de Dermatologie, ChuvA, Ecole Nationale Vétérinaire d’Alfort, 94700 Maisons-Alfort, France; (A.B.); (N.C.-F.)
| | - Noëlle Cochet-Faivre
- Unité de Dermatologie, ChuvA, Ecole Nationale Vétérinaire d’Alfort, 94700 Maisons-Alfort, France; (A.B.); (N.C.-F.)
| | - Edouard Reyes-Gomez
- “Biology of the Neuromuscular System” Team, INSERM, IMRB, Univ Paris-Est Créteil, Ecole Nationale Vétérinaire d’Alfort, 94700 Maisons-Alfort, France; (L.C.); (E.R.-G.)
- Unité d’Histologie et d’Anatomie Pathologique, BioPôle Alfort, Ecole Nationale Vétérinaire d’Alfort, 94700 Maisons-Alfort, France
| | - Tosso Leeb
- Institute of Genetics, Vetsuisse Faculty, University of Bern, 3001 Bern, Switzerland; (S.K.); (V.J.)
- Dermfocus, University of Bern, 3001 Bern, Switzerland
- Correspondence: ; Tel.: +41-31-684-2326
| |
Collapse
|
7
|
SAAT H, SAHIN I, DUZKALE N, GONUL M, BAHSI T. Genetic Etiology of Ichthyosis in Turkish Patients: Nextgeneration Sequencing Identified Seven Novel Mutations. Medeni Med J 2022; 37:126-130. [PMID: 35734965 PMCID: PMC9234365 DOI: 10.4274/mmj.galenos.2022.39924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Objective: Ichthyosis is a clinically heterogeneous group of genodermatoses characterized by widespread drying and scaling of the skin. It is also a genetically heterogeneous disorder, and 67 genes associated with the disease have been identified to date. However, there are still undiscovered genes causing the disease. Methods: We investigated 19 Turkish patients from 17 unrelated families using clinical exome sequencing or multigene panel screening. Results: Sixteen likely pathogenic or pathogenic variants were detected in 13 unrelated patients. We identified “variant of unknown significance” alteration in only one patient. Seven novel variants were identified in ABCA12, ALOX12B, and ALOXE3. The most commonly mutated gene was TGM1, followed by ABCA12 and ALOX12B. Conclusions: Because of the wide genetic variability of ichthyosis, it is difficult to diagnose the disease quickly and definitively. The clinical use of next-generation sequencing (NGS) methodologies is beneficial in the diagnostic approach to ichthyosis and genetic counseling. This study highlights the underlying molecular cause of ichthyosis by determining the mutational spectrum in a cohort of 19 patients. This study is the first and largest research from Turkey using NGS that highlights all ichthyosis subtypes.
Collapse
|
8
|
Leeb T, Roosje P, Welle M. Genetics of inherited skin disorders in dogs. Vet J 2021; 279:105782. [PMID: 34861369 DOI: 10.1016/j.tvjl.2021.105782] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 11/16/2021] [Accepted: 11/29/2021] [Indexed: 01/22/2023]
Abstract
Canine genodermatoses represent a broad spectrum of diseases with diverse phenotypes. Modern genetic technology including whole genome sequencing has expedited the identification of novel genes and greatly simplified the establishment of genetic diagnoses in such heterogeneous disorders. The precise genetic diagnosis of a heritable skin disorder is essential for the appropriate counselling of owners regarding the course of the disease, prognosis and implications for breeding. Understanding the underlying pathophysiology is a prerequisite to developing specific, targeted or individualized therapeutic approaches. This review aims to create a comprehensive overview of canine genodermatoses and their respective genetic aetiology known to date. Raising awareness of genodermatoses in dogs is important and this review may help clinicians to apply modern genetics in daily clinical practice, so that a precise diagnoses can be established in suspected genodermatoses.
Collapse
Affiliation(s)
- Tosso Leeb
- Institute of Genetics, Vetsuisse Faculty, University of Bern, 3001 Bern, Switzerland; Dermfocus, University of Bern, 3001 Bern, Switzerland.
| | - Petra Roosje
- Dermfocus, University of Bern, 3001 Bern, Switzerland; Division of Clinical Dermatology, Department of Clinical Veterinary Medicine, Vetsuisse Faculty, University of Bern, 3001 Bern, Switzerland
| | - Monika Welle
- Dermfocus, University of Bern, 3001 Bern, Switzerland; Institute of Animal Pathology, Vetsuisse Faculty, University of Bern, 3001 Bern, Switzerland
| |
Collapse
|