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Stanbury K, Schofield EC, McLaughlin B, Forman OP, Mellersh CS. Exonic Short Interspersed Nuclear Element Insertion in FAM161A Is Associated with Autosomal Recessive Progressive Retinal Atrophy in the English Shepherd. Genes (Basel) 2024; 15:952. [PMID: 39062732 PMCID: PMC11275866 DOI: 10.3390/genes15070952] [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: 06/19/2024] [Revised: 07/08/2024] [Accepted: 07/16/2024] [Indexed: 07/28/2024] Open
Abstract
Progressive retinal atrophies (PRAs) are a genetically heterogeneous group of inherited eye diseases that affect over 100 breeds of dog. The initial clinical sign is visual impairment in scotopic conditions, as a consequence of rod photoreceptor cell degeneration. Photopic vision degeneration then follows, due to progression of the disease to the cone photoreceptors, and ultimately results in complete blindness. Two full-sibling English Shepherds were diagnosed with PRA at approximately 5 years old and tested clear of all published PRA genetic variants. This study sought to identify the novel PRA-associated variant segregating in the breed. We utilised a combined approach of whole genome sequencing of the probands and homozygosity mapping of four cases and 22 controls and identified a short interspersed nuclear element within an alternatively spliced exon in FAM161A. The XP_005626197.1 c.17929_ins210 variant was homozygous in six PRA cases and heterozygous or absent in control dogs, consistent with a recessive mode of inheritance. The insertion is predicted to extend exon 4 by 39 aberrant amino acids followed by an early termination stop codon. PRA is intractable to treatment, so the development of a genetic screening test, based on the associated variant, is significant, because it provides dog breeders/owners with a means of reducing the frequency of the disease variant within this breed as well as minimising the risk of breeding puppies that will develop this blinding disease.
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Affiliation(s)
- Katherine Stanbury
- Canine Genetics Centre, Department of Veterinary Medicine, University of Cambridge, Cambridge CB3 0ES, UK
| | - Ellen C. Schofield
- Canine Genetics Centre, Department of Veterinary Medicine, University of Cambridge, Cambridge CB3 0ES, UK
| | - Bryan McLaughlin
- Canine Genetics Centre, Department of Veterinary Medicine, University of Cambridge, Cambridge CB3 0ES, UK
| | - Oliver P. Forman
- Wisdom Panel, Mars Petcare (Science and Diagnostics Division), Freeby Lane, Waltham on the Wolds, Leicestershire LE14 4RS, UK
| | - Cathryn S. Mellersh
- Canine Genetics Centre, Department of Veterinary Medicine, University of Cambridge, Cambridge CB3 0ES, UK
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2
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Ghilardi S, Bagardi M, Frattini S, Barbariga GE, Brambilla PG, Minozzi G, Polli M. Genotypic and allelic frequencies of progressive rod-cone degeneration and other main variants associated with progressive retinal atrophy in Italian dogs. Vet Rec Open 2023; 10:e77. [PMID: 38028226 PMCID: PMC10665785 DOI: 10.1002/vro2.77] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 09/28/2023] [Accepted: 10/18/2023] [Indexed: 12/01/2023] Open
Abstract
Background Progressive retinal atrophy (PRA) is a group of canine inherited retinal disorders affecting up to 100 breeds. Genetic tests are available. The aim of this study was to retrospectively evaluate the genetic variants associated with PRA among dogs residing in Italy. Methods Genetic data of 20 variants associated with different forms of PRA were collected through DNA tests over a 10-year period for several dog breeds in the Italian canine population. Allelic and genotypic frequencies were calculated. Results A total of 1467 DNA tests were conducted for 1180 dogs. Progressive rod-cone degeneration (PRCD) was the most tested form of PRA, with 58.15% (n = 853) of the DNA tests. Among the widespread breeds in Italy, Labrador retrievers and toy poodles showed a prevalence of heterozygous carriers higher than 15%. Among the others, 175 DNA tests for golden retrievers (GR) showed a prevalence of heterozygous carriers of 13.04% (n = 12) for GR-PRA1 and 8.43% (n = 7) for GR-PRA2. The zwergschnauzer breed was tested for the type B and/or the type B1 forms of PRA with 25.32% (n = 20) heterozygous carriers and 0%, respectively. Conclusion The study offers an overview of the prevalence of PRCD and other PRA forms within some of the most popular breeds in Italy.
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Affiliation(s)
- Sara Ghilardi
- Department of Veterinary Medicine and Animal Sciences—DIVASUniversity of MilanLodiItaly
| | - Mara Bagardi
- Department of Veterinary Medicine and Animal Sciences—DIVASUniversity of MilanLodiItaly
| | | | - Giulia E. Barbariga
- Department of Veterinary Medicine and Animal Sciences—DIVASUniversity of MilanLodiItaly
| | - Paola G. Brambilla
- Department of Veterinary Medicine and Animal Sciences—DIVASUniversity of MilanLodiItaly
| | - Giulietta Minozzi
- Department of Veterinary Medicine and Animal Sciences—DIVASUniversity of MilanLodiItaly
| | - Michele Polli
- Department of Veterinary Medicine and Animal Sciences—DIVASUniversity of MilanLodiItaly
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3
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Gerhardt MJ, Petersen-Jones SM, Michalakis S. CNG channel-related retinitis pigmentosa. Vision Res 2023; 208:108232. [PMID: 37054604 PMCID: PMC10373105 DOI: 10.1016/j.visres.2023.108232] [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: 02/13/2023] [Revised: 03/27/2023] [Accepted: 03/27/2023] [Indexed: 04/15/2023]
Abstract
The genes CNGA1 and CNGB1 encode the alpha and beta subunits of the rod CNG channel, a ligand-gated cation channel whose activity is controlled by cyclic guanosine monophosphate (cGMP). Autosomal inherited mutations in either of the genes lead to a progressive rod-cone retinopathy known as retinitis pigmentosa (RP). The rod CNG channel is expressed in the plasma membrane of the outer segment and functions as a molecular switch that converts light-mediated changes in cGMP into a voltage and Ca2+ signal. Here, we will first review the molecular properties and physiological role of the rod CNG channel and then discuss the characteristics of CNG-related RP. Finally, we will summarize recent activities in the field of gene therapy aimed at developing therapies for CNG-related RP.
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Affiliation(s)
- Maximilian J Gerhardt
- Department of Ophthalmology, University Hospital, LMU Munich, Mathildenstraße 8, 80336 München, Germany
| | - Simon M Petersen-Jones
- College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824, United States
| | - Stylianos Michalakis
- Department of Ophthalmology, University Hospital, LMU Munich, Mathildenstraße 8, 80336 München, Germany.
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4
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Biology, Pathobiology and Gene Therapy of CNG Channel-Related Retinopathies. Biomedicines 2023; 11:biomedicines11020269. [PMID: 36830806 PMCID: PMC9953513 DOI: 10.3390/biomedicines11020269] [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: 01/08/2023] [Revised: 01/16/2023] [Accepted: 01/17/2023] [Indexed: 01/21/2023] Open
Abstract
The visual process begins with the absorption of photons by photopigments of cone and rod photoreceptors in the retina. In this process, the signal is first amplified by a cyclic guanosine monophosphate (cGMP)-based signaling cascade and then converted into an electrical signal by cyclic nucleotide-gated (CNG) channels. CNG channels are purely ligand-gated channels whose activity can be controlled by cGMP, which induces a depolarizing Na+/Ca2+ current upon binding to the channel. Structurally, CNG channels belong to the superfamily of pore-loop cation channels and share structural similarities with hyperpolarization-activated cyclic nucleotide (HCN) and voltage-gated potassium (KCN) channels. Cone and rod photoreceptors express distinct CNG channels encoded by homologous genes. Mutations in the genes encoding the rod CNG channel (CNGA1 and CNGB1) result in retinitis-pigmentosa-type blindness. Mutations in the genes encoding the cone CNG channel (CNGA3 and CNGB3) lead to achromatopsia. Here, we review the molecular properties of CNG channels and describe their physiological and pathophysiological roles in the retina. Moreover, we summarize recent activities in the field of gene therapy aimed at developing the first gene therapies for CNG channelopathies.
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5
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Preclinical Models of Retinitis Pigmentosa. Methods Mol Biol 2022; 2560:181-215. [PMID: 36481897 DOI: 10.1007/978-1-0716-2651-1_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Retinitis pigmentosa (RP) is the name for a group of phenotypically-related heritable retinal degenerative disorders. Many genes have been implicated as causing variants of RP, and while the clinical phenotypes are remarkably similar, they may differ in age of onset, progression, and severity. Common inheritance patterns for specific genes connected with the development of the disorder include autosomal dominant, autosomal recessive, and X-linked. Modeling the disease in animals and other preclinical systems offers a cost-conscious, ethical, and time-efficient method for studying the disease subtypes. The history of RP models is briefly examined, and both naturally occurring and transgenic preclinical models of RP in many different organisms are discussed. Syndromic forms of RP and models thereof are reviewed as well.
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6
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Urkasemsin G, Pongpanich M, Sariya L, Kongcharoen A, Buddhirongawatr R, Rungarunlert S, Ferreira JN, Chetruengchai W, Phokaew C, Srichomthong C, Shotelersuk V. Whole genome sequencing identifies a homozygous nonsense mutation in the JPH2 gene in Shih Tzu dogs with progressive retinal atrophy. Anim Genet 2021; 52:714-719. [PMID: 34231238 DOI: 10.1111/age.13118] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/24/2021] [Indexed: 11/28/2022]
Abstract
Progressive retinal atrophy (PRA), common autosomal recessive disorder affecting several dog breeds including Shih Tzu, is characterized by degeneration of photoreceptors leading to blindness. To identify PRA genetic variants, three affected and 15 unaffected Shih Tzu and 20 non-Shih Tzu were recruited. Dogs underwent ophthalmologic examination and electroretinography, revealing hallmark retina pathological changes and an abnormal electroretinography in all affected dogs but not in unaffected dogs. WGS was performed. Non-synonymous homozygous variants were searched in coding regions of genes involved in retinal diseases/development; the criterion was that variants should only be present in affected dogs and should be absent in both unaffected and 46 genomes of dogs (from an available evolutionary database). Only one out of the 109 identified variants is predicted to harbor a high-impact consequence, a nonsense c.452A>C (p.L151X) in the JPH2 gene. The genotype of JPH2 variant in all 38 dogs was determined with Sanger sequencing. All three affected dogs, but none of the 35 unaffected, were homozygous for the nonsense variant. JPH2 has been previously found to be expressed in several excitable cells/tissues including retina photoreceptors. Hence, JPH2 is a candidate gene for PRA in Shih Tzu.
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Affiliation(s)
- G Urkasemsin
- Department of Preclinic and Applied Animal Science, Faculty of Veterinary Science, Mahidol University, Nakhon Pathom, 73170, Thailand
| | - M Pongpanich
- Department of Mathematics and Computer Science, Faculty of Science, Chulalongkorn University, Bangkok, 10330, Thailand.,Age-related Inflammation and Degeneration Research Unit, Chulalongkorn University, Bangkok, 10330, Thailand
| | - L Sariya
- The Monitoring and Surveillance Center for Zoonotic Diseases in Wildlife and Exotic Animals, Faculty of Veterinary Science, Mahidol University, Nakhon Pathom, 73170, Thailand
| | - A Kongcharoen
- Prasu-Arthorn Animal Hospital, Faculty of Veterinary Science, Mahidol University, Nakhon Pathom, 73170, Thailand
| | - R Buddhirongawatr
- Department of Clinical Sciences and Public Health, Faculty of Veterinary Science, Mahidol University, Nakhon Pathom, 73170, Thailand
| | - S Rungarunlert
- Department of Preclinic and Applied Animal Science, Faculty of Veterinary Science, Mahidol University, Nakhon Pathom, 73170, Thailand
| | - J N Ferreira
- Exocrine Gland Biology and Regeneration Research Group, Faculty of Dentistry, Chulalongkorn University, Bangkok, 10330, Thailand
| | - W Chetruengchai
- Department of Pediatrics, Faculty of Medicine, Center of Excellence for Medical Genomics, Medical Genomics Cluster, Chulalongkorn University, Bangkok, 10330, Thailand.,Excellence Center for Genomics and Precision Medicine, King Chulalongkorn Memorial Hospital, The Thai Red Cross Society, Bangkok, 10330, Thailand
| | - C Phokaew
- Department of Pediatrics, Faculty of Medicine, Center of Excellence for Medical Genomics, Medical Genomics Cluster, Chulalongkorn University, Bangkok, 10330, Thailand.,Excellence Center for Genomics and Precision Medicine, King Chulalongkorn Memorial Hospital, The Thai Red Cross Society, Bangkok, 10330, Thailand
| | - C Srichomthong
- Department of Pediatrics, Faculty of Medicine, Center of Excellence for Medical Genomics, Medical Genomics Cluster, Chulalongkorn University, Bangkok, 10330, Thailand.,Excellence Center for Genomics and Precision Medicine, King Chulalongkorn Memorial Hospital, The Thai Red Cross Society, Bangkok, 10330, Thailand
| | - V Shotelersuk
- Department of Pediatrics, Faculty of Medicine, Center of Excellence for Medical Genomics, Medical Genomics Cluster, Chulalongkorn University, Bangkok, 10330, Thailand.,Excellence Center for Genomics and Precision Medicine, King Chulalongkorn Memorial Hospital, The Thai Red Cross Society, Bangkok, 10330, Thailand
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7
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Hitti-Malin RJ, Burmeister LM, Ricketts SL, Lewis TW, Pettitt L, Boursnell M, Schofield EC, Sargan D, Mellersh CS. A LINE-1 insertion situated in the promoter of IMPG2 is associated with autosomal recessive progressive retinal atrophy in Lhasa Apso dogs. BMC Genet 2020; 21:100. [PMID: 32894063 PMCID: PMC7487703 DOI: 10.1186/s12863-020-00911-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 08/30/2020] [Indexed: 12/30/2022] Open
Abstract
Background Canine progressive retinal atrophies are a group of hereditary retinal degenerations in dogs characterised by depletion of photoreceptor cells in the retina, which ultimately leads to blindness. PRA in the Lhasa Apso (LA) dog has not previously been clinically characterised or described in the literature, but owners in the UK are advised to have their dog examined through the British Veterinary Association/ Kennel Club/ International Sheep Dog Society (BVA/KC/ISDS) eye scheme annually, and similar schemes that are in operation in other countries. After the exclusion of 25 previously reported canine retinal mutations in LA PRA-affected dogs, we sought to identify the genetic cause of PRA in this breed. Results Analysis of whole-exome sequencing data of three PRA-affected LA and three LA without signs of PRA did not identify any exonic or splice site variants, suggesting the causal variant was non-exonic. We subsequently undertook a genome-wide association study (GWAS), which identified a 1.3 Mb disease-associated region on canine chromosome 33, followed by whole-genome sequencing analysis that revealed a long interspersed element-1 (LINE-1) insertion upstream of the IMPG2 gene. IMPG2 has previously been implicated in human retinal disease; however, until now no canine PRAs have been associated with this gene. The identification of this PRA-associated variant has enabled the development of a DNA test for this form of PRA in the breed, here termed PRA4 to distinguish it from other forms of PRA described in other breeds. This test has been used to determine the genotypes of over 900 LA dogs. A large cohort of genotyped dogs was used to estimate the allele frequency as between 0.07–0.1 in the UK LA population. Conclusions Through the use of GWAS and subsequent sequencing of a PRA case, we have identified a LINE-1 insertion in the retinal candidate gene IMPG2 that is associated with a form of PRA in the LA dog. Validation of this variant in 447 dogs of 123 breeds determined it was private to LA dogs. We envisage that, over time, the developed DNA test will offer breeders the opportunity to avoid producing dogs affected with this form of PRA.
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Affiliation(s)
- Rebekkah J Hitti-Malin
- Kennel Club Genetics Centre, Animal Health Trust, Lanwades Park, Newmarket, Suffolk, CB8 7UU, UK. .,Department of Veterinary Medicine, University of Cambridge, Cambridge, CB3 0ES, UK.
| | - Louise M Burmeister
- Kennel Club Genetics Centre, Animal Health Trust, Lanwades Park, Newmarket, Suffolk, CB8 7UU, UK
| | - Sally L Ricketts
- Kennel Club Genetics Centre, Animal Health Trust, Lanwades Park, Newmarket, Suffolk, CB8 7UU, UK
| | - Thomas W Lewis
- The Kennel Club, London, W1J 8AB, UK.,School of Veterinary Medicine and Science, The University of Nottingham, Sutton Bonington, Leicestershire, LE12 5RD, UK
| | - Louise Pettitt
- Kennel Club Genetics Centre, Animal Health Trust, Lanwades Park, Newmarket, Suffolk, CB8 7UU, UK
| | - Mike Boursnell
- Kennel Club Genetics Centre, Animal Health Trust, Lanwades Park, Newmarket, Suffolk, CB8 7UU, UK
| | - Ellen C Schofield
- Kennel Club Genetics Centre, Animal Health Trust, Lanwades Park, Newmarket, Suffolk, CB8 7UU, UK
| | - David Sargan
- Department of Veterinary Medicine, University of Cambridge, Cambridge, CB3 0ES, UK
| | - Cathryn S Mellersh
- Kennel Club Genetics Centre, Animal Health Trust, Lanwades Park, Newmarket, Suffolk, CB8 7UU, UK
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8
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Guo CC, Majewski T, Zhang L, Yao H, Bondaruk J, Wang Y, Zhang S, Wang Z, Lee JG, Lee S, Cogdell D, Zhang M, Wei P, Grossman HB, Kamat A, Duplisea JJ, Ferguson JE, Huang H, Dadhania V, Gao J, Dinney C, Weinstein JN, Baggerly K, McConkey D, Czerniak B. Dysregulation of EMT Drives the Progression to Clinically Aggressive Sarcomatoid Bladder Cancer. Cell Rep 2020; 27:1781-1793.e4. [PMID: 31067463 DOI: 10.1016/j.celrep.2019.04.048] [Citation(s) in RCA: 81] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 02/28/2019] [Accepted: 04/10/2019] [Indexed: 12/17/2022] Open
Abstract
Sarcomatoid urothelial bladder cancer (SARC) displays a high propensity for distant metastasis and is associated with short survival. We report a comprehensive genomic analysis of 28 cases of SARC and 84 cases of conventional urothelial carcinoma (UC), with the TCGA cohort of 408 muscle-invasive bladder cancers serving as the reference. SARCs show a distinct mutational landscape, with enrichment of TP53, RB1, and PIK3CA mutations. They are related to the basal molecular subtype of conventional UCs and could be divided into epithelial-basal and more clinically aggressive mesenchymal subsets on the basis of TP63 and its target gene expression levels. Other analyses reveal that SARCs are driven by downregulation of homotypic adherence genes and dysregulation of the EMT network, and nearly half exhibit a heavily infiltrated immune phenotype. Our observations have important implications for prognostication and the development of more effective therapies for this highly lethal variant of bladder cancer.
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Affiliation(s)
- Charles C Guo
- Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Tadeusz Majewski
- Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Li Zhang
- Department of Environmental Health, University of Cincinnati, Cincinnati, OH, USA
| | - Hui Yao
- Department of Bioinformatics & Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Jolanta Bondaruk
- Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Yan Wang
- Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Shizhen Zhang
- Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Ziqiao Wang
- Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - June Goo Lee
- Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Sangkyou Lee
- Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - David Cogdell
- Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Miao Zhang
- Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Peng Wei
- Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - H Barton Grossman
- Department of Urology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Ashish Kamat
- Department of Urology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | | | - James Edward Ferguson
- Department of Urology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - He Huang
- Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Vipulkumar Dadhania
- Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Jianjun Gao
- Department of Genitourinary Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Colin Dinney
- Department of Urology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - John N Weinstein
- Department of Bioinformatics & Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Keith Baggerly
- Department of Bioinformatics & Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - David McConkey
- Johns Hopkins Greenberg Bladder Cancer Institute, Johns Hopkins University, Baltimore, MD, USA
| | - Bogdan Czerniak
- Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
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9
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Huskey ALW, Goebel K, Lloveras-Fuentes C, McNeely I, Merner ND. Whole genome sequencing for the investigation of canine mammary tumor inheritance - an initial assessment of high-risk breast cancer genes reveal BRCA2 and STK11 variants potentially associated with risk in purebred dogs. Canine Med Genet 2020. [PMCID: PMC7491476 DOI: 10.1186/s40575-020-00084-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Background Although, in general, cancer is considered a multifactorial disease, clustering of particular cancers in pedigrees suggests a genetic predisposition and could explain why some dog breeds appear to have an increased risk of certain cancers. To our knowledge, there have been no published reports of whole genome sequencing to investigate inherited canine mammary tumor (CMT) risk, and with little known about CMT genetic susceptibility, we carried out whole genome sequencing on 14 purebred dogs diagnosed with mammary tumors from four breed-specific pedigrees. Following sequencing, each dog’s data was processed through a bioinformatics pipeline. This initial report highlights variants in orthologs of human breast cancer susceptibility genes. Results The overall whole genome and exome coverage averages were 26.0X and 25.6X, respectively, with 96.1% of the genome and 96.7% of the exome covered at least 10X. Of the average 7.9 million variants per dog, initial analyses involved surveying variants in orthologs of human breast cancer susceptibility genes, BRCA1, BRCA2, CDH1, PTEN, STK11, and TP53, and identified 19 unique coding variants that were validated through PCR and Sanger sequencing. Statistical analyses identified variants in BRCA2 and STK11 that appear to be associated with CMT, and breed-specific analyses revealed the breeds at the highest risk. Several additional BRCA2 variants showed trends toward significance, but have conflicting interpretations of pathogenicity, and correspond to variants of unknown significance in humans, which require further investigation. Variants in other genes were noted but did not appear to be associated with disease. Conclusions Whole genome sequencing proves to be an effective method to elucidate risk of CMT. Risk variants in orthologs of human breast cancer susceptibility genes have been identified. Ultimately, these whole genome sequencing efforts have provided a plethora of data that can also be assessed for novel discovery and have the potential to lead to breakthroughs in canine and human research through comparative analyses.
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10
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Charbel Issa P, Reuter P, Kühlewein L, Birtel J, Gliem M, Tropitzsch A, Whitcroft KL, Bolz HJ, Ishihara K, MacLaren RE, Downes SM, Oishi A, Zrenner E, Kohl S, Hummel T. Olfactory Dysfunction in Patients With CNGB1-Associated Retinitis Pigmentosa. JAMA Ophthalmol 2019; 136:761-769. [PMID: 29800053 DOI: 10.1001/jamaophthalmol.2018.1621] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Importance Co-occurrence of retinitis pigmentosa (RP) and olfactory dysfunction may have a common genetic cause. Objective To report olfactory function and the retinal phenotype in patients with biallelic mutations in CNGB1, a gene coding for a signal transduction channel subunit expressed in rod photoreceptors and olfactory sensory neurons. Design, Setting, and Participants This case series was conducted from August 2015 through July 2017. The setting was a multicenter study involving 4 tertiary referral centers for inherited retinal dystrophies. Participants were 9 patients with CNGB1-associated RP. Main Outcomes and Measures Results of olfactory testing, ocular phenotyping, and molecular genetic testing using targeted next-generation sequencing. Results Nine patients were included in the study, 3 of whom were female. Their ages ranged between 34 and 79 years. All patients had an early onset of night blindness but were usually not diagnosed as having RP before the fourth decade because of slow retinal degeneration. Retinal features were characteristic of a rod-cone dystrophy. Olfactory testing revealed reduced or absent olfactory function, with all except one patient scoring in the lowest quartile in relation to age-related norms. Brain magnetic resonance imaging and electroencephalography measurements in response to olfactory stimulation were available for 1 patient and revealed no visible olfactory bulbs and reduced responses to odor, respectively. Molecular genetic testing identified 5 novel (c.1312C>T, c.2210G>A, c.2492+1G>A, c.2763C>G, and c.3044_3050delGGAAATC) and 5 previously reported mutations in CNGB1. Conclusions and Relevance Mutations in CNGB1 may cause an autosomal recessive RP-olfactory dysfunction syndrome characterized by a slow progression of retinal degeneration and variable anosmia or hyposmia.
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Affiliation(s)
- Peter Charbel Issa
- Oxford Eye Hospital, Oxford University Hospitals National Health Service (NHS) Foundation Trust, Oxford, United Kingdom.,Nuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom.,Department of Ophthalmology, University of Bonn, Bonn, Germany
| | - Peggy Reuter
- Centre for Ophthalmology, Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
| | - Laura Kühlewein
- Centre for Ophthalmology, Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
| | - Johannes Birtel
- Department of Ophthalmology, University of Bonn, Bonn, Germany
| | - Martin Gliem
- Oxford Eye Hospital, Oxford University Hospitals National Health Service (NHS) Foundation Trust, Oxford, United Kingdom.,Department of Ophthalmology, University of Bonn, Bonn, Germany
| | - Anke Tropitzsch
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Tübingen, Tübingen, Germany
| | - Katherine L Whitcroft
- University College London (UCL) Ear Institute and Royal National Throat, Nose and Ear Hospital, London, United Kingdom.,Centre for the Study of the Senses, Institute of Philosophy, School of Advanced Study, University of London, London, United Kingdom.,Smell and Taste Clinic, Department of Otorhinolaryngology-Head and Neck Surgery, Technische Universität Dresden, Dresden, Germany
| | - Hanno J Bolz
- Bioscientia Center for Human Genetics, Ingelheim, Germany.,Institute of Human Genetics, University Hospital of Cologne, Cologne, Germany
| | - Kenji Ishihara
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Robert E MacLaren
- Oxford Eye Hospital, Oxford University Hospitals National Health Service (NHS) Foundation Trust, Oxford, United Kingdom.,Nuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Susan M Downes
- Oxford Eye Hospital, Oxford University Hospitals National Health Service (NHS) Foundation Trust, Oxford, United Kingdom.,Nuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Akio Oishi
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Eberhart Zrenner
- Centre for Ophthalmology, Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
| | - Susanne Kohl
- Centre for Ophthalmology, Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
| | - Thomas Hummel
- Smell and Taste Clinic, Department of Otorhinolaryngology-Head and Neck Surgery, Technische Universität Dresden, Dresden, Germany
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11
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Identification of a CNGB1 Frameshift Mutation in a Han Chinese Family with Retinitis Pigmentosa. Optom Vis Sci 2019; 95:1155-1161. [PMID: 30451805 DOI: 10.1097/opx.0000000000001305] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
SIGNIFICANCE Retinitis pigmentosa (RP) is a severe hereditary retinal disorder characterized by progressive degeneration of rod and cone photoreceptors. This study identified a novel frameshift mutation, c.385delC, p.(L129WfsTer148), in the cyclic nucleotide-gated channel beta 1 (CNGB1) gene of a consanguineous Han Chinese family with autosomal recessive RP (arRP). This expands the spectrum of CNGB1 gene variants in RP cases and possibly refines future genetic counseling. PURPOSE The present study sought to identify potential pathogenetic gene mutations in a five-generation consanguineous Han Chinese family with RP. METHODS Two members of a five-generation consanguineous Han Chinese pedigree with arRP and 100 normal individuals were enrolled in this study. Exome sequencing was performed on the 70-year-old male proband from a consanguineous family to screen potential pathogenic mutations according to the American College of Medical Genetics and Genomics for the interpretation of sequence variants. Sanger sequencing was performed on the proband, the proband's unaffected son, and 100 normal individuals to verify the disease-causing mutation. RESULTS A novel frameshift mutation, c.385delC, p.(L129WfsTer148), with homozygous status in the CNGB1 gene was identified in the proband of the family with arRP, and the mutation with heterozygous status was carried by the asymptomatic son. CONCLUSIONS The c.385delC (p.(L129WfsTer148)) mutation in the CNGB1 gene screened by exome sequencing is probably responsible for the RP phenotype in this family. The result expands the spectrum of CNGB1 gene variants in RP cases and possibly refines future genetic counseling.
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12
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Kim KK, Seung BJ, Kim D, Park HM, Lee S, Song DW, Lee G, Cheong JH, Nam H, Sur JH, Kim S. Whole-exome and whole-transcriptome sequencing of canine mammary gland tumors. Sci Data 2019; 6:147. [PMID: 31413331 PMCID: PMC6694171 DOI: 10.1038/s41597-019-0149-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Accepted: 06/26/2019] [Indexed: 12/20/2022] Open
Abstract
Studies of naturally occurring cancers in dogs, which share many genetic and environmental factors with humans, provide valuable information as a comparative model for studying the mechanisms of human cancer pathogenesis. While individual and small-scale studies of canine cancers are underway, more generalized multi-omics studies have not been attempted due to the lack of large-scale and well-controlled genomic data. Here, we produced reliable whole-exome and whole-transcriptome sequencing data of 197 canine mammary cancers and their matched controls, annotated with rich clinical and biological features. Our dataset provides useful reference points for comparative analysis with human cancers and for developing novel diagnostic and therapeutic technologies for cancers in pet dogs.
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Affiliation(s)
- Ka-Kyung Kim
- Department of Biomedical Systems Informatics and Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea
| | - Byung-Joon Seung
- Department of Veterinary Pathology, Small Animal Tumor Diagnostic Center, College of Veterinary Medicine, Konkuk University, Seoul, 05029, Republic of Korea
| | - Dohyun Kim
- School of Electrical Engineering and Computer Science, Gwangju Institute of Science and Technology (GIST), Gwangju, 61005, Republic of Korea
| | - Hee-Myung Park
- Department of Veterinary Internal Medicine, College of Veterinary Medicine, Konkuk University, Seoul, 05029, Republic of Korea
| | - Sejoon Lee
- Precision Medicine Center, Seoul National University Bundang Hospital, Seongnam, 13620, Republic of Korea
| | - Doo-Won Song
- Department of Veterinary Internal Medicine, College of Veterinary Medicine, Konkuk University, Seoul, 05029, Republic of Korea
| | - Gunho Lee
- Graduate Program for Nanomedical Science, Yonsei University, Seoul, 03722, Republic of Korea
| | - Jae-Ho Cheong
- Department of Biomedical Systems Informatics and Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea
- Department of Surgery, Severance Hospital, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea
| | - Hojung Nam
- School of Electrical Engineering and Computer Science, Gwangju Institute of Science and Technology (GIST), Gwangju, 61005, Republic of Korea.
| | - Jung-Hyang Sur
- Department of Veterinary Pathology, Small Animal Tumor Diagnostic Center, College of Veterinary Medicine, Konkuk University, Seoul, 05029, Republic of Korea.
| | - Sangwoo Kim
- Department of Biomedical Systems Informatics and Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea.
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13
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A SIX6 Nonsense Variant in Golden Retrievers with Congenital Eye Malformations. Genes (Basel) 2019; 10:genes10060454. [PMID: 31207931 PMCID: PMC6628151 DOI: 10.3390/genes10060454] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 06/04/2019] [Accepted: 06/11/2019] [Indexed: 12/22/2022] Open
Abstract
Causative genetic variants for more than 30 heritable eye disorders in dogs have been reported. For other clinically described eye disorders, the genetic cause is still unclear. We investigated four Golden Retriever litters segregating for highly variable congenital eye malformations. Several affected puppies had unilateral or bilateral retina dysplasia and/or optic nerve hypoplasia. The four litters shared the same father or grandfather suggesting a heritable condition with an autosomal dominant mode of inheritance. The genome of one affected dog was sequenced and compared to 601 control genomes. A heterozygous private nonsense variant, c.487C>T, was found in the SIX6 gene. This variant is predicted to truncate about a third of the open reading frame, p.(Gln163*). We genotyped all available family members and 464 unrelated Golden Retrievers. All three available cases were heterozygous. Five additional close relatives including the common sire were also heterozygous, but did not show any obvious eye phenotypes. The variant was absent from the 464 unrelated Golden Retrievers and 17 non-affected siblings of the cases. The SIX6 protein is a homeobox transcription factor with a known role in eye development. In humans and other species, SIX6 loss of function variants were reported to cause congenital eye malformations. This strongly suggests that the c.487C>T variant detected contributed to the observed eye malformations. We hypothesize that the residual amount of functional SIX6 protein likely to be expressed in heterozygous dogs is sufficient to explain the observed incomplete penetrance and the varying severity of the eye defects in the affected dogs.
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14
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Hitti RJ, Oliver JAC, Schofield EC, Bauer A, Kaukonen M, Forman OP, Leeb T, Lohi H, Burmeister LM, Sargan D, Mellersh CS. Whole Genome Sequencing of Giant Schnauzer Dogs with Progressive Retinal Atrophy Establishes NECAP1 as a Novel Candidate Gene for Retinal Degeneration. Genes (Basel) 2019; 10:genes10050385. [PMID: 31117272 PMCID: PMC6562617 DOI: 10.3390/genes10050385] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 05/08/2019] [Accepted: 05/17/2019] [Indexed: 12/30/2022] Open
Abstract
Canine progressive retinal atrophies (PRA) are genetically heterogeneous diseases characterized by retinal degeneration and subsequent blindness. PRAs are untreatable and affect multiple dog breeds, significantly impacting welfare. Three out of seven Giant Schnauzer (GS) littermates presented with PRA around four years of age. We sought to identify the causal variant to improve our understanding of the aetiology of this form of PRA and to enable development of a DNA test. Whole genome sequencing of two PRA-affected full-siblings and both unaffected parents was performed. Variants were filtered based on those segregating appropriately for an autosomal recessive disorder and predicted to be deleterious. Successive filtering against 568 canine genomes identified a single nucleotide variant in the gene encoding NECAP endocytosis associated 1 (NECAP1): c.544G>A (p.Gly182Arg). Five thousand one hundred and thirty canids of 175 breeds, 10 cross-breeds and 3 wolves were genotyped for c.544G>A. Only the three PRA-affected GS were homozygous (allele frequency in GS, excluding proband family = 0.015). In addition, we identified heterozygotes belonging to Spitz and Dachshund varieties, demonstrating c.544G>A segregates in other breeds of German origin. This study, in parallel with the known retinal expression and role of NECAP1 in clathrin mediated endocytosis (CME) in synapses, presents NECAP1 as a novel candidate gene for retinal degeneration in dogs and other species.
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Affiliation(s)
- Rebekkah J Hitti
- Kennel Club Genetics Centre, Animal Health Trust, Lanwades Park, Newmarket, Suffolk CB8 7UU, UK.
- Department of Veterinary Medicine, University of Cambridge, Cambridge CB3 0ES, UK.
| | - James A C Oliver
- Kennel Club Genetics Centre, Animal Health Trust, Lanwades Park, Newmarket, Suffolk CB8 7UU, UK.
| | - Ellen C Schofield
- Kennel Club Genetics Centre, Animal Health Trust, Lanwades Park, Newmarket, Suffolk CB8 7UU, UK.
| | - Anina Bauer
- Institute of Genetics, University of Bern, 3001 Bern, Switzerland.
| | - Maria Kaukonen
- Department of Veterinary Biosciences, University of Helsinki, 00014 Helsinki, Finland.
- Department of Medical Genetics, University of Helsinki, 00014 Helsinki, Finland.
- Folkhälsan Research Center, 00290 Helsinki, Finland.
| | - Oliver P Forman
- Wisdom Health, Waltham-on-the-Wolds, Leicestershire LE14 4RS, UK.
| | - Tosso Leeb
- Institute of Genetics, University of Bern, 3001 Bern, Switzerland.
| | - Hannes Lohi
- Department of Veterinary Biosciences, University of Helsinki, 00014 Helsinki, Finland.
- Department of Medical Genetics, University of Helsinki, 00014 Helsinki, Finland.
- Folkhälsan Research Center, 00290 Helsinki, Finland.
| | - Louise M Burmeister
- Kennel Club Genetics Centre, Animal Health Trust, Lanwades Park, Newmarket, Suffolk CB8 7UU, UK.
| | - David Sargan
- Department of Veterinary Medicine, University of Cambridge, Cambridge CB3 0ES, UK.
| | - Cathryn S Mellersh
- Kennel Club Genetics Centre, Animal Health Trust, Lanwades Park, Newmarket, Suffolk CB8 7UU, UK.
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15
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Natural models for retinitis pigmentosa: progressive retinal atrophy in dog breeds. Hum Genet 2019; 138:441-453. [PMID: 30904946 DOI: 10.1007/s00439-019-01999-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 03/14/2019] [Indexed: 01/24/2023]
Abstract
Retinitis pigmentosa (RP) is a heterogeneous group of inherited retinal disorders eventually leading to blindness with different ages of onset, progression and severity. Human RP, first characterized by the progressive degeneration of rod photoreceptor cells, shows high genetic heterogeneity with more than 90 genes identified. However, about one-third of patients have no known genetic causes. Interestingly, dogs are also severely affected by similar diseases, called progressive retinal atrophy (PRA). Indeed, RP and PRA have comparable clinical signs, physiopathology and outcomes, similar diagnosis methods and most often, orthologous genes are involved. The many different dog PRAs often segregate in specific breeds. Indeed, undesired alleles have been selected and amplified through drastic selection and excessive use of inbreeding. Out of the 400 breeds, nearly 100 have an inherited form of PRA, which are natural animal models that can be used to investigate the genetics, disease progression and therapies in dogs for the benefit of both dogs and humans. Recent knowledge on the canine genome and access to new genotyping and sequencing technologies now efficiently allows the identification of mutations involved in canine genetic diseases. To date, PRA genes identified in dog breeds correspond to the same genes in humans and represent relevant RP models, and new genes found in dogs represent good candidate for still unknown human RP. We present here a review of the main advantages of the dog models for human RP with the genes already identified and an X-linked PRA in the Border collie as a model for orphan X-linked RPs in human.
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16
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Brown EA, Thomasy SM, Murphy CJ, Bannasch DL. Genetic analysis of optic nerve head coloboma in the Nova Scotia Duck Tolling Retriever identifies discordance with the NHEJ1 intronic deletion (collie eye anomaly mutation). Vet Ophthalmol 2018; 21:144-150. [PMID: 28702949 PMCID: PMC5766432 DOI: 10.1111/vop.12488] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Collie eye anomaly (CEA) encompasses a spectrum of different ophthalmic phenotypes from clinically inconsequential choroidal hypoplasia to blindness from coloboma of the optic nerve head (ONH). A previous study found a 7.8-kb deletion in intron 4 of the NHEJ1 gene to be associated with CEA. A genetic test based on this association is recommended for many breeds, including the Nova Scotia Duck Tolling Retriever (NSDTR). Collection of ONH coloboma-affected NSDTR showed lack of concordance of the NHEJ1 intronic deletion with ONH coloboma. Using genomewide single nucleotide polymorphism (SNP) genotyping in 7 ONH coloboma-affected NSDTR cases and 47 unaffected NSDTR controls with no ophthalmic signs, one SNP, located on chromosome 7, demonstrated genomewide significance. However, high genomic inflation may have confounded the results. Therefore, the genomewide association study was repeated using EMMAX to control for population structure in the cohort of 7 cases and 47 controls. However, no regions of the genome were significantly associated with ONH coloboma. These results failed to document significant association with the CEA locus. Due to the complex genetic etiology of ONH coloboma, the NHEJ1 intronic deletion test results should be carefully considered when making breeding decisions. If the goal is to select for visually competent dogs, our data suggest that eye examinations of puppies would be more effective as a guide in selection of breeding pairs than relying solely on currently available genetic tests.
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Affiliation(s)
- Emily A. Brown
- Department of Population Health and Reproduction, School of Veterinary Medicine, University of California—Davis
| | - Sara M. Thomasy
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California—Davis
| | - Christopher J. Murphy
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, Department of Ophthalmology & Vision Science, School of Medicine, University of California—Davis
| | - Danika L. Bannasch
- Department of Population Health and Reproduction, School of Veterinary Medicine, University of California—Davis, Davis, CA 95616,
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17
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Broeckx BJG, Derrien T, Mottier S, Wucher V, Cadieu E, Hédan B, Le Béguec C, Botherel N, Lindblad-Toh K, Saunders JH, Deforce D, André C, Peelman L, Hitte C. An exome sequencing based approach for genome-wide association studies in the dog. Sci Rep 2017; 7:15680. [PMID: 29142306 PMCID: PMC5688105 DOI: 10.1038/s41598-017-15947-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 11/04/2017] [Indexed: 12/12/2022] Open
Abstract
Genome-wide association studies (GWAS) are widely used to identify loci associated with phenotypic traits in the domestic dog that has emerged as a model for Mendelian and complex traits. However, a disadvantage of GWAS is that it always requires subsequent fine-mapping or sequencing to pinpoint causal mutations. Here, we performed whole exome sequencing (WES) and canine high-density (cHD) SNP genotyping of 28 dogs from 3 breeds to compare the SNP and linkage disequilibrium characteristics together with the power and mapping precision of exome-guided GWAS (EG-GWAS) versus cHD-based GWAS. Using simulated phenotypes, we showed that EG-GWAS has a higher power than cHD to detect associations within target regions and less power outside target regions, with power being influenced further by sample size and SNP density. We analyzed two real phenotypes (hair length and furnishing), that are fixed in certain breeds to characterize mapping precision of the known causal mutations. EG-GWAS identified the associated exonic and 3'UTR variants within the FGF5 and RSPO2 genes, respectively, with only a few samples per breed. In conclusion, we demonstrated that EG-GWAS can identify loci associated with Mendelian phenotypes both within and across breeds.
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Affiliation(s)
- Bart J G Broeckx
- Laboratory of Animal Genetics, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
| | - Thomas Derrien
- Institut de Génétique et Développement de Rennes, CNRS-URM6290, Université Rennes1, Rennes, France
| | - Stéphanie Mottier
- Institut de Génétique et Développement de Rennes, CNRS-URM6290, Université Rennes1, Rennes, France
| | - Valentin Wucher
- Institut de Génétique et Développement de Rennes, CNRS-URM6290, Université Rennes1, Rennes, France
| | - Edouard Cadieu
- Institut de Génétique et Développement de Rennes, CNRS-URM6290, Université Rennes1, Rennes, France
| | - Benoît Hédan
- Institut de Génétique et Développement de Rennes, CNRS-URM6290, Université Rennes1, Rennes, France
| | - Céline Le Béguec
- Institut de Génétique et Développement de Rennes, CNRS-URM6290, Université Rennes1, Rennes, France
| | - Nadine Botherel
- Institut de Génétique et Développement de Rennes, CNRS-URM6290, Université Rennes1, Rennes, France
| | - Kerstin Lindblad-Toh
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
- Science for Life Laboratory, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Jimmy H Saunders
- Department of Medical Imaging and Orthopedics, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Dieter Deforce
- Laboratory of Pharmaceutical Biotechnology, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium
| | - Catherine André
- Institut de Génétique et Développement de Rennes, CNRS-URM6290, Université Rennes1, Rennes, France
| | - Luc Peelman
- Laboratory of Animal Genetics, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Christophe Hitte
- Institut de Génétique et Développement de Rennes, CNRS-URM6290, Université Rennes1, Rennes, France.
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18
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Cox ML, Evans JM, Davis AG, Guo LT, Levy JR, Starr-Moss AN, Salmela E, Hytönen MK, Lohi H, Campbell KP, Clark LA, Shelton GD. Exome sequencing reveals independent SGCD deletions causing limb girdle muscular dystrophy in Boston terriers. Skelet Muscle 2017; 7:15. [PMID: 28697784 PMCID: PMC5506588 DOI: 10.1186/s13395-017-0131-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Accepted: 06/23/2017] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Limb-girdle muscular dystrophies (LGMDs) are a heterogeneous group of inherited autosomal myopathies that preferentially affect voluntary muscles of the shoulders and hips. LGMD has been clinically described in several breeds of dogs, but the responsible mutations are unknown. The clinical presentation in dogs is characterized by marked muscle weakness and atrophy in the shoulder and hips during puppyhood. METHODS Following clinical evaluation, the identification of the dystrophic histological phenotype on muscle histology, and demonstration of the absence of sarcoglycan-sarcospan complex by immunostaining, whole exome sequencing was performed on five Boston terriers: one affected dog and its three family members and one unrelated affected dog. RESULTS Within sarcoglycan-δ (SGCD), a two base pair deletion segregating with LGMD in the family was discovered, and a deletion encompassing exons 7 and 8 was found in the unrelated dog. Both mutations are predicted to cause an absence of SGCD protein, confirmed by immunohistochemistry. The mutations are private to each family. CONCLUSIONS Here, we describe the first cases of canine LGMD characterized at the molecular level with the classification of LGMD2F.
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Affiliation(s)
- Melissa L. Cox
- CAG GmbH - Center for Animal Genetics, Paul-Ehrlich-Str. 23, 72076 Tubingen, Germany
| | - Jacquelyn M. Evans
- Department of Genetics and Biochemistry, Clemson University, 130 McGinty Ct., Clemson, SC 29634 USA
| | - Alexander G. Davis
- Department of Genetics and Biochemistry, Clemson University, 130 McGinty Ct., Clemson, SC 29634 USA
| | - Ling T. Guo
- Department of Pathology, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093 USA
| | - Jennifer R. Levy
- Howard Hughes Medical Institute, Department of Molecular Physiology and Biophysics, Department of Neurology, The University of Iowa Roy J. and Lucille A. Carver College of Medicine, 4283 Carver Biomedical Research Building, 285 Newton Road, Iowa City, Iowa 52242-1101 USA
- Department of Neurology, Roy J. and Lucille A. Carver College of Medicine, The University of Iowa, 4283 Carver Biomedical Research Building, 285 Newton Road, Iowa City, Iowa 52242 USA
| | - Alison N. Starr-Moss
- Department of Genetics and Biochemistry, Clemson University, 130 McGinty Ct., Clemson, SC 29634 USA
| | - Elina Salmela
- Department of Veterinary Biosciences and Research Programs Unit, University of Helsinki, Haartmaninkatu 8, FI-00290 Helsinki, Finland
- Folkhälsan Institute of Genetics, Helsinki, Finland
| | - Marjo K. Hytönen
- Department of Veterinary Biosciences and Research Programs Unit, University of Helsinki, Haartmaninkatu 8, FI-00290 Helsinki, Finland
- Folkhälsan Institute of Genetics, Helsinki, Finland
| | - Hannes Lohi
- Department of Veterinary Biosciences and Research Programs Unit, University of Helsinki, Haartmaninkatu 8, FI-00290 Helsinki, Finland
- Folkhälsan Institute of Genetics, Helsinki, Finland
| | - Kevin P. Campbell
- Howard Hughes Medical Institute, Department of Molecular Physiology and Biophysics, Department of Neurology, The University of Iowa Roy J. and Lucille A. Carver College of Medicine, 4283 Carver Biomedical Research Building, 285 Newton Road, Iowa City, Iowa 52242-1101 USA
- Department of Neurology, Roy J. and Lucille A. Carver College of Medicine, The University of Iowa, 4283 Carver Biomedical Research Building, 285 Newton Road, Iowa City, Iowa 52242 USA
| | - Leigh Anne Clark
- Department of Genetics and Biochemistry, Clemson University, 130 McGinty Ct., Clemson, SC 29634 USA
| | - G. Diane Shelton
- Department of Pathology, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093 USA
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Yeh CY, Koehl KL, Harman CD, Iwabe S, Guzman JM, Petersen-Jones SM, Kardon RH, Komáromy AM. Assessment of Rod, Cone, and Intrinsically Photosensitive Retinal Ganglion Cell Contributions to the Canine Chromatic Pupillary Response. Invest Ophthalmol Vis Sci 2017; 58:65-78. [PMID: 28061512 PMCID: PMC5231906 DOI: 10.1167/iovs.16-19865] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Purpose The purpose of this study was to evaluate a chromatic pupillometry protocol for specific functional assessment of rods, cones, and intrinsically photosensitive retinal ganglion cells (ipRGCs) in dogs. Methods Chromatic pupillometry was tested and compared in 37 dogs in different stages of primary loss of rod, cone, and combined rod/cone and optic nerve function, and in 5 wild-type (WT) dogs. Eyes were stimulated with 1-s flashes of dim (1 cd/m2) and bright (400 cd/m2) blue light (for scotopic conditions) or bright red (400 cd/m2) light with 25-cd/m2 blue background (for photopic conditions). Canine retinal melanopsin/Opn4 was cloned, and its expression was evaluated using real-time quantitative reverse transcription-PCR and immunohistochemistry. Results Mean ± SD percentage of pupil constriction amplitudes induced by scotopic dim blue (scDB), scotopic bright blue (scBB), and photopic bright red (phBR) lights in WT dogs were 21.3% ± 10.6%, 50.0% ± 17.5%, and 19.4% ± 7.4%, respectively. Melanopsin-mediated responses to scBB persisted for several minutes (7.7 ± 4.6 min) after stimulus offset. In dogs with inherited retinal degeneration, loss of rod function resulted in absent scDB responses, followed by decreased phBR responses with disease progression and loss of cone function. Primary loss of cone function abolished phBR responses but preserved those responses to blue light (scDB and scBB). Although melanopsin/Opn4 expression was diminished with retinal degeneration, melanopsin-expressing ipRGCs were identified for the first time in both WT and degenerated canine retinas. Conclusions Pupil responses elicited by light stimuli of different colors and intensities allowed differential functional assessment of canine rods, cones, and ipRGCs. Chromatic pupillometry offers an effective tool for diagnosing retinal and optic nerve diseases.
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Affiliation(s)
- Connie Y Yeh
- College of Veterinary Medicine, Michigan State University, East Lansing, Michigan, United States 2School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Kristin L Koehl
- College of Veterinary Medicine, Michigan State University, East Lansing, Michigan, United States
| | - Christine D Harman
- College of Veterinary Medicine, Michigan State University, East Lansing, Michigan, United States
| | - Simone Iwabe
- School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - José M Guzman
- School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Simon M Petersen-Jones
- College of Veterinary Medicine, Michigan State University, East Lansing, Michigan, United States
| | - Randy H Kardon
- Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, Iowa, United States 4Veterans Affairs Health Care System, Iowa City, Iowa, United States
| | - András M Komáromy
- College of Veterinary Medicine, Michigan State University, East Lansing, Michigan, United States 2School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
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20
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Generalized myoclonic epilepsy with photosensitivity in juvenile dogs caused by a defective DIRAS family GTPase 1. Proc Natl Acad Sci U S A 2017; 114:2669-2674. [PMID: 28223533 DOI: 10.1073/pnas.1614478114] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The clinical and electroencephalographic features of a canine generalized myoclonic epilepsy with photosensitivity and onset in young Rhodesian Ridgeback dogs (6 wk to 18 mo) are described. A fully penetrant recessive 4-bp deletion was identified in the DIRAS family GTPase 1 (DIRAS1) gene with an altered expression pattern of DIRAS1 protein in the affected brain. This neuronal DIRAS1 gene with a proposed role in cholinergic transmission provides not only a candidate for human myoclonic epilepsy but also insights into the disease etiology, while establishing a spontaneous model for future intervention studies and functional characterization.
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21
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van Steenbeek FG, Hytönen MK, Leegwater PAJ, Lohi H. The canine era: the rise of a biomedical model. Anim Genet 2016; 47:519-27. [PMID: 27324307 DOI: 10.1111/age.12460] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/18/2016] [Indexed: 12/29/2022]
Abstract
Since the annotation of its genome a decade ago, the dog has proven to be an excellent model for the study of inherited diseases. A large variety of spontaneous simple and complex phenotypes occur in dogs, providing physiologically relevant models to corresponding human conditions. In addition, gene discovery is facilitated in clinically less heterogeneous purebred dogs with closed population structures because smaller study cohorts and fewer markers are often sufficient to expose causal variants. Here, we review the development of genomic resources from microsatellites to whole-genome sequencing and give examples of successful findings that have followed the technological progress. The increasing amount of whole-genome sequence data warrants better functional annotation of the canine genome to more effectively utilise this unique model to understand genetic contributions in morphological, behavioural and other complex traits.
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Affiliation(s)
- F G van Steenbeek
- Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 104, 3508 TD, Utrecht, the Netherlands.
| | - M K Hytönen
- Research Programs Unit, Molecular Neurology, Department of Veterinary Biosciences 00014, Folkhälsan Research Center, University of Helsinki, Helsinki, Finland
| | - P A J Leegwater
- Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 104, 3508 TD, Utrecht, the Netherlands
| | - H Lohi
- Research Programs Unit, Molecular Neurology, Department of Veterinary Biosciences 00014, Folkhälsan Research Center, University of Helsinki, Helsinki, Finland
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Evans JM, Cox ML, Huska J, Li F, Gaitero L, Guo LT, Casal ML, Granzier HL, Shelton GD, Clark LA. Exome sequencing reveals a nebulin nonsense mutation in a dog model of nemaline myopathy. Mamm Genome 2016; 27:495-502. [PMID: 27215641 DOI: 10.1007/s00335-016-9644-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 05/06/2016] [Indexed: 12/25/2022]
Abstract
Nemaline myopathy (NM) is a congenital muscle disorder associated with muscle weakness, hypotonia, and rod bodies in the skeletal muscle fibers. Mutations in 10 genes have been implicated in human NM, but spontaneous cases in dogs have not been genetically characterized. We identified a novel recessive myopathy in a family of line-bred American bulldogs (ABDs); rod bodies in muscle biopsies established this as NM. Using SNP profiles from the nuclear family, we evaluated inheritance patterns at candidate loci and prioritized TNNT1 and NEB for further investigation. Whole exome sequencing of the dam, two affected littermates, and an unaffected littermate revealed a nonsense mutation in NEB (g.52734272 C>A, S8042X). Whole tissue gel electrophoresis and western blots confirmed a lack of full-length NEB in affected tissues, suggesting nonsense-mediated decay. The pathogenic variant was absent from 120 dogs of 24 other breeds and 100 unrelated ABDs, suggesting that it occurred recently and may be private to the family. This study presents the first molecularly characterized large animal model of NM, which could provide new opportunities for therapeutic approaches.
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Affiliation(s)
- Jacquelyn M Evans
- Department of Genetics and Biochemistry, Clemson University, Clemson, SC, 29634, USA
| | - Melissa L Cox
- CAG GmbH - Center for Animal Genetics, Tübingen, Germany
| | - Jonathan Huska
- Ontario Veterinary College, University of Guelph, Guelph, ON, Canada
| | - Frank Li
- Department of Cellular and Molecular Medicine, University of Arizona, Tucson, AZ, 85724, USA
| | - Luis Gaitero
- Ontario Veterinary College, University of Guelph, Guelph, ON, Canada
| | - Ling T Guo
- Department of Pathology, University of California San Diego, La Jolla, CA, 92093, USA
| | - Margaret L Casal
- School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Henk L Granzier
- Department of Cellular and Molecular Medicine, University of Arizona, Tucson, AZ, 85724, USA
| | - G Diane Shelton
- Department of Pathology, University of California San Diego, La Jolla, CA, 92093, USA.
| | - Leigh Anne Clark
- Department of Genetics and Biochemistry, Clemson University, Clemson, SC, 29634, USA.
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23
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Hytönen MK, Arumilli M, Lappalainen AK, Owczarek-Lipska M, Jagannathan V, Hundi S, Salmela E, Venta P, Sarkiala E, Jokinen T, Gorgas D, Kere J, Nieminen P, Drögemüller C, Lohi H. Molecular Characterization of Three Canine Models of Human Rare Bone Diseases: Caffey, van den Ende-Gupta, and Raine Syndromes. PLoS Genet 2016; 12:e1006037. [PMID: 27187611 PMCID: PMC4871343 DOI: 10.1371/journal.pgen.1006037] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Accepted: 04/18/2016] [Indexed: 12/03/2022] Open
Abstract
One to two percent of all children are born with a developmental disorder requiring pediatric hospital admissions. For many such syndromes, the molecular pathogenesis remains poorly characterized. Parallel developmental disorders in other species could provide complementary models for human rare diseases by uncovering new candidate genes, improving the understanding of the molecular mechanisms and opening possibilities for therapeutic trials. We performed various experiments, e.g. combined genome-wide association and next generation sequencing, to investigate the clinico-pathological features and genetic causes of three developmental syndromes in dogs, including craniomandibular osteopathy (CMO), a previously undescribed skeletal syndrome, and dental hypomineralization, for which we identified pathogenic variants in the canine SLC37A2 (truncating splicing enhancer variant), SCARF2 (truncating 2-bp deletion) and FAM20C (missense variant) genes, respectively. CMO is a clinical equivalent to an infantile cortical hyperostosis (Caffey disease), for which SLC37A2 is a new candidate gene. SLC37A2 is a poorly characterized member of a glucose-phosphate transporter family without previous disease associations. It is expressed in many tissues, including cells of the macrophage lineage, e.g. osteoclasts, and suggests a disease mechanism, in which an impaired glucose homeostasis in osteoclasts compromises their function in the developing bone, leading to hyperostosis. Mutations in SCARF2 and FAM20C have been associated with the human van den Ende-Gupta and Raine syndromes that include numerous features similar to the affected dogs. Given the growing interest in the molecular characterization and treatment of human rare diseases, our study presents three novel physiologically relevant models for further research and therapy approaches, while providing the molecular identity for the canine conditions. Rare developmental disorders make a major contribution to pediatric hospital admissions and mortality. There is a growing interest in the development of therapeutics for these conditions, but that requires understanding of the genetic cause and pathology. Research can be facilitated by physiologically relevant models, such as dogs with corresponding disorders. We have characterized the clinical features and genetic causes of three developmental syndromes in dogs, including craniomandibular osteopathy (CMO), a previously undescribed skeletal syndrome, and dental hypomineralization, for which we identified mutations in the canine SLC37A2, SCARF2 and FAM20C genes, respectively. CMO is a clinical equivalent to an infantile cortical hyperostosis (Caffey disease) for which SLC37A2 is a new candidate gene. SLC37A2 is a glucose-phosphate transporter in osteoclasts, and its defect suggests an impaired glucose homeostasis in developing bone, leading to hyperostosis. Mutations in the SCARF2 and FAM20C genes have been associated with the human van den Ende-Gupta and Raine syndromes. Our study provides molecular identity for the canine conditions and presents three novel physiologically relevant models of human rare diseases.
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Affiliation(s)
- Marjo K. Hytönen
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
- Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland
- The Folkhälsan Institute of Genetics, Helsinki, Finland
| | - Meharji Arumilli
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
- Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland
- The Folkhälsan Institute of Genetics, Helsinki, Finland
| | - Anu K. Lappalainen
- Department of Equine and Small Animal Medicine, University of Helsinki, Helsinki, Finland
| | | | - Vidhya Jagannathan
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Sruthi Hundi
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
- Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland
- The Folkhälsan Institute of Genetics, Helsinki, Finland
| | - Elina Salmela
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
- Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland
- The Folkhälsan Institute of Genetics, Helsinki, Finland
| | - Patrick Venta
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan, United States of America
| | - Eva Sarkiala
- Department of Equine and Small Animal Medicine, University of Helsinki, Helsinki, Finland
| | - Tarja Jokinen
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
- Department of Equine and Small Animal Medicine, University of Helsinki, Helsinki, Finland
| | - Daniela Gorgas
- Division of Clinical Radiology, Department of Clinical Veterinary Medicine, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Juha Kere
- Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland
- The Folkhälsan Institute of Genetics, Helsinki, Finland
- Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden
| | - Pekka Nieminen
- Department of Oral and Maxillofacial Diseases, University of Helsinki, Helsinki, Finland
| | - Cord Drögemüller
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Hannes Lohi
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
- Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland
- The Folkhälsan Institute of Genetics, Helsinki, Finland
- * E-mail:
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24
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Palanova A. The genetics of inherited retinal disorders in dogs: implications for diagnosis and management. VETERINARY MEDICINE-RESEARCH AND REPORTS 2016; 7:41-51. [PMID: 30050836 PMCID: PMC6042528 DOI: 10.2147/vmrr.s63537] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Dogs are affected by many hereditary diseases just as humans are. One group of these diseases comprises of retinal disorders, which are a growing problem in canine breeding. These disorders are heterogeneous, with diverse causative mutations and modes of inheritance. Some affect only one breed, while others may affect many breeds; some breeds are affected by only one disease, while others can be affected by two or more. Dog breeders should take into account the presence of any deleterious alleles when choosing parents for the next generation.
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Affiliation(s)
- Anna Palanova
- Department of Tumor Biology, Institute of Animal Physiology and Genetics, v. v. i., Academy of Sciences of the Czech Republic, Libechov, Czech Republic,
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25
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Broeckx BJG, Coopman F, Verhoeven GEC, De Keulenaer S, De Meester E, Bavegems V, Smets P, Van Ryssen B, Van Nieuwerburgh F, Deforce D. Toward the most ideal case-control design with related and unrelated dogs in whole-exome sequencing studies. Anim Genet 2015; 47:200-7. [PMID: 26689130 DOI: 10.1111/age.12400] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/27/2015] [Indexed: 11/29/2022]
Abstract
With the recent development of whole-exome sequencing enrichment designs for the dog, a novel tool for disease-association studies became available. The aim of disease-association studies is to identify one or a very limited number of putative causal variants or genes from the large pool of genetic variation. To maximize the efficiency of these studies and to provide some directions of what to expect, we evaluated the effect on variant reduction for various combinations of cases and controls for both dominant and recessive types of inheritance assuming variable degrees of penetrance and detectance. In this study, variant data of 14 dogs (13 Labrador Retrievers and one Dogue de Bordeaux), obtained by whole-exome sequencing, were analyzed. In the filtering process, we found that unrelated dogs from the same breed share up to 70% of their variants, which is likely a consequence of the breeding history of the dog. For the designs tested with unrelated dogs, combining two cases and two controls gave the best result. These results were improved further by adding closely related dogs. Reduced penetrance and/or detectance has a drastic effect on the efficiency and is likely to have a profound effect on the sample size needed to elucidate the causal variant. Overall, we demonstrated that sequencing a small number of dogs results in a marked reduction of variants that are likely sufficient to pinpoint causal variants or genes.
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Affiliation(s)
- B J G Broeckx
- Laboratory of Pharmaceutical Biotechnology, Ghent University, 9000, Ghent, Belgium
| | - F Coopman
- Department of Applied Biosciences, University College Ghent, 9000, Ghent, Belgium
| | - G E C Verhoeven
- Department of Medical Imaging and Small Animal Orthopaedics, Ghent University, 9820, Merelbeke, Belgium
| | - S De Keulenaer
- Laboratory of Pharmaceutical Biotechnology, Ghent University, 9000, Ghent, Belgium
| | - E De Meester
- Laboratory of Pharmaceutical Biotechnology, Ghent University, 9000, Ghent, Belgium
| | - V Bavegems
- Department of Medicine and Clinical Biology of Small Animals, Ghent University, 9820, Merelbeke, Belgium
| | - P Smets
- Department of Medicine and Clinical Biology of Small Animals, Ghent University, 9820, Merelbeke, Belgium
| | - B Van Ryssen
- Department of Medical Imaging and Small Animal Orthopaedics, Ghent University, 9820, Merelbeke, Belgium
| | - F Van Nieuwerburgh
- Laboratory of Pharmaceutical Biotechnology, Ghent University, 9000, Ghent, Belgium
| | - D Deforce
- Laboratory of Pharmaceutical Biotechnology, Ghent University, 9000, Ghent, Belgium
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26
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Reddy B, Kelawala DN, Shah T, Patel AB, Patil DB, Parikh PV, Patel N, Parmar N, Mohapatra AB, Singh KM, Menon R, Pandya D, Jakhesara SJ, Koringa PG, Rao MV, Joshi CG. Identification of putative SNPs in progressive retinal atrophy affected Canis lupus familiaris using exome sequencing. Mamm Genome 2015; 26:638-49. [PMID: 26515695 DOI: 10.1007/s00335-015-9607-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Accepted: 10/08/2015] [Indexed: 11/30/2022]
Abstract
Progressive retinal atrophy (PRA) is one of the major causes of retinal photoreceptor cell degeneration in canines. The inheritance pattern of PRA is autosomal recessive and genetically heterogeneous. Here, using targeted sequencing technology, we have performed exome sequencing of 10 PRA-affected (Spitz=7, Cocker Spaniel=1, Lhasa Aphso=1 and Spitz-Labrador cross breed=1) and 6 normal (Spitz=5, Cocker Spaniel=1) dogs. The high-throughput sequencing using 454-Roche Titanium sequencer generated about 2.16 Giga bases of raw data. Initially, we have successfully identified 25,619 single nucleotide polymorphisms (SNPs) that passed the stringent SNP calling parameters. Further, we performed association study on the cohort, and the highly significant (0.001) associations were short-listed and investigated in-depth. Out of the 171 significant SNPs, 113 were previously unreported. Interestingly, six among them were non-synonymous coding (NSC) SNPs, which includes CPPED1 A>G (p.M307V), PITRM1 T>G (p.S715A), APP G>A (p.T266M), RNF213 A>G (p.V1482A), C>A (p.V1456L), and SLC46A3 G>A (p.R168Q). On the other hand, 35 out of 113 unreported SNPs were falling in regulatory regions such as 3'-UTR, 5'-UTR, etc. In-depth bioinformatics analysis revealed that majority of NSC SNPs have damaging effect and alter protein stability. This study highlighted the genetic markers associated with PRA, which will help to develop genetic assay-based screening in effective breeding.
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Affiliation(s)
- Bhaskar Reddy
- Ome Research Facility, Department of Animal Biotechnology, Anand Agricultural University, Anand, Gujarat, 388001, India.,Department of Zoology, Genetic Diagnostic Centre, University School of Sciences, Gujarat University, Ahmedabad, Gujarat, 380009, India
| | - Divyesh N Kelawala
- Department of Veterinary Surgery & Radiology, College of Veterinary Science & Animal Husbandry, Anand Agricultural University, Anand, Gujarat, 388001, India
| | - Tejas Shah
- Ome Research Facility, Department of Animal Biotechnology, Anand Agricultural University, Anand, Gujarat, 388001, India
| | - Anand B Patel
- Ome Research Facility, Department of Animal Biotechnology, Anand Agricultural University, Anand, Gujarat, 388001, India
| | - Deepak B Patil
- Department of Veterinary Surgery & Radiology, College of Veterinary Science & Animal Husbandry, Anand Agricultural University, Anand, Gujarat, 388001, India
| | - Pinesh V Parikh
- Department of Veterinary Surgery & Radiology, College of Veterinary Science & Animal Husbandry, Anand Agricultural University, Anand, Gujarat, 388001, India
| | - Namrata Patel
- Ome Research Facility, Department of Animal Biotechnology, Anand Agricultural University, Anand, Gujarat, 388001, India
| | - Nidhi Parmar
- Ome Research Facility, Department of Animal Biotechnology, Anand Agricultural University, Anand, Gujarat, 388001, India
| | - Amit B Mohapatra
- Ome Research Facility, Department of Animal Biotechnology, Anand Agricultural University, Anand, Gujarat, 388001, India
| | - Krishna M Singh
- Datar Genetics Ltd, F-8, D Road, Ambad, Nasik, Maharashtra, 422010, India
| | - Ramesh Menon
- Ome Research Facility, Department of Animal Biotechnology, Anand Agricultural University, Anand, Gujarat, 388001, India
| | - Dipal Pandya
- Ome Research Facility, Department of Animal Biotechnology, Anand Agricultural University, Anand, Gujarat, 388001, India
| | - Subhash J Jakhesara
- Ome Research Facility, Department of Animal Biotechnology, Anand Agricultural University, Anand, Gujarat, 388001, India
| | - Prakash G Koringa
- Ome Research Facility, Department of Animal Biotechnology, Anand Agricultural University, Anand, Gujarat, 388001, India
| | - Mandava V Rao
- Department of Zoology, Genetic Diagnostic Centre, University School of Sciences, Gujarat University, Ahmedabad, Gujarat, 380009, India
| | - Chaitanya G Joshi
- Ome Research Facility, Department of Animal Biotechnology, Anand Agricultural University, Anand, Gujarat, 388001, India.
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27
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Nemet I, Tian G, Imanishi Y. Organization of cGMP sensing structures on the rod photoreceptor outer segment plasma membrane. Channels (Austin) 2015; 8:528-35. [PMID: 25616687 DOI: 10.4161/19336950.2014.973776] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
A diffusion barrier segregates the plasma membrane of the rod photoreceptor outer segment into 2 domains; one which is optimized for the conductance of ions in the phototransduction cascade and another for disk membrane synthesis. We propose the former to be named "phototransductive plasma membrane domain," and the latter to be named "disk morphogenic plasma membrane domain." Within the phototransductive plasma membrane, cGMP-gated channels are concentrated in striated membrane features, which are proximally located to the sites of active cGMP production within the disk membranes. For proper localization of cGMP-gated channel to the phototransductive plasma membrane, the glutamic acid-rich protein domain encoded in the β subunit plays a critical role. Quantitative study suggests that the disk morphogenic domain likely plays an important role in enriching rhodopsin prior to its sequestration into closed disk membranes. Thus, this and our previous studies provide new insight into the mechanism that spatially organizes the vertebrate phototransduction cascade.
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Key Words
- CNGA1
- CNGA1, cyclic nucleotide gated channel α-1
- CNGB1
- CNGB1, cyclic nucleotide gated channel β-1
- Dend2, Dendra2
- GARP, glutamic acid-rich protein
- GC, guanylate cyclase
- GCAP, guanylate cyclase activating protein
- GPCR, G protein-coupled receptor
- IS, inner segment
- OS, outer segment
- PDE6, phosphodiesterase 6
- Rho, rhodopsin
- cyclic nucleotide gated channel
- morphogenesis
- photoreceptor
- retina
- rhodopsin
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Affiliation(s)
- Ina Nemet
- a Department of Pharmacology; School of Medicine ; Case Western Reserve University ; Cleveland , OH USA
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28
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The pros and cons of vertebrate animal models for functional and therapeutic research on inherited retinal dystrophies. Prog Retin Eye Res 2015; 48:137-59. [DOI: 10.1016/j.preteyeres.2015.04.004] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Revised: 04/12/2015] [Accepted: 04/16/2015] [Indexed: 01/19/2023]
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30
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Ahonen SJ, Arumilli M, Seppälä E, Hakosalo O, Kaukonen MK, Komáromy AM, Lohi H. Increased expression of MERTK is associated with a unique form of canine retinopathy. PLoS One 2014; 9:e114552. [PMID: 25517981 PMCID: PMC4269413 DOI: 10.1371/journal.pone.0114552] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Accepted: 11/10/2014] [Indexed: 01/25/2023] Open
Abstract
Progressive retinal degenerations are among the most common causes of blindness both in human and in dogs. Canine progressive retinal atrophy (PRA) resembles human retinitis pigmentosa (RP) and is typically characterized by a progressive loss of rod photoreceptors followed by a loss of cone function. The disease gradually progress from the loss of night and day vision to a complete blindness. We have recently described a unique form of retinopathy characterized by the multifocal gray/brown discoloration and thinning of the retina in the Swedish Vallhund (SV) breed. We aimed to identify the genetic cause by performing a genome wide association analysis in a cohort of 18 affected and 10 healthy control dogs using Illumina's canine 22k SNP array. We mapped the disease to canine chromosome 17 (p = 7.7×10−5) and found a 6.1 Mb shared homozygous region in the affected dogs. A combined analysis of the GWAS and replication data with additional 60 dogs confirmed the association (p = 4.3×10−8, OR = 11.2 for homozygosity). A targeted resequencing of the entire associated region in four cases and four controls with opposite risk haplotypes identified several variants in the coding region of functional candidate genes, such as a known retinopathy gene, MERTK. However, none of the identified coding variants followed a compelling case- or breed-specific segregation pattern. The expression analyses of four candidate genes in the region, MERTK, NPHP1, ANAPC1 and KRCC1, revealed specific upregulation of MERTK in the retina of the affected dogs. Collectively, these results indicate that the retinopathy is associated with overexpression of MERTK, however further investigation is needed to discover the regulatory mutation for the better understanding of the disease pathogenesis. Our study establishes a novel gain-of-function model for the MERTK biology and provides a therapy model for retinopathy MERTK inhibitors. Meanwhile, a marker-based genetic counseling can be developed to revise breeding programs.
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Affiliation(s)
- Saija J. Ahonen
- Department of Veterinary Biosciences and Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland
- The Folkhälsan Institute of Genetics, Helsinki, Finland
| | - Meharji Arumilli
- Department of Veterinary Biosciences and Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland
- The Folkhälsan Institute of Genetics, Helsinki, Finland
| | - Eija Seppälä
- Department of Veterinary Biosciences and Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland
- The Folkhälsan Institute of Genetics, Helsinki, Finland
| | - Osmo Hakosalo
- Department of Veterinary Biosciences and Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland
- The Folkhälsan Institute of Genetics, Helsinki, Finland
| | - Maria K. Kaukonen
- Department of Veterinary Biosciences and Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland
- The Folkhälsan Institute of Genetics, Helsinki, Finland
| | - András M. Komáromy
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, Michigan, United States of America
- Department of Clinical Studies, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Hannes Lohi
- Department of Veterinary Biosciences and Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland
- The Folkhälsan Institute of Genetics, Helsinki, Finland
- * E-mail:
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31
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Development and performance of a targeted whole exome sequencing enrichment kit for the dog (Canis Familiaris Build 3.1). Sci Rep 2014; 4:5597. [PMID: 24998260 PMCID: PMC4083258 DOI: 10.1038/srep05597] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Accepted: 06/18/2014] [Indexed: 11/29/2022] Open
Abstract
Whole exome sequencing is a technique that aims to selectively sequence all exons of protein-coding genes. A canine whole exome sequencing enrichment kit was designed based on the latest canine reference genome (build 3.1.72). Its performance was tested by sequencing 2 exome captures, each consisting of 4 pre-capture pooled, barcoded Illumina libraries on an Illumina HiSeq 2500. At an average sequencing depth of 102x, 83 to 86% of the target regions were completely sequenced with a minimum coverage of five and 90% of the reads mapped on the target regions. Additionally, it is shown that the reproducibility within and between captures is high and that pooling four samples per capture is a valid option. Overall, we have demonstrated the strong performance of this WES enrichment kit and are confident it will be a valuable tool in future disease association studies.
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32
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Mellersh CS. The genetics of eye disorders in the dog. Canine Genet Epidemiol 2014; 1:3. [PMID: 26401320 PMCID: PMC4574392 DOI: 10.1186/2052-6687-1-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Accepted: 03/06/2014] [Indexed: 11/10/2022] Open
Abstract
Inherited forms of eye disease are arguably the best described and best characterized of all inherited diseases in the dog, at both the clinical and molecular level and at the time of writing 29 different mutations have been documented in the scientific literature that are associated with an inherited ocular disorder in the dog. The dog has already played an important role in the identification of genes that are important for ocular development and function as well as emerging therapies for inherited blindness in humans. Similarities in disease phenotype and eye structure and function between dog and man, together with the increasingly sophisticated genetic tools that are available for the dog, mean that the dog is likely to play an ever increasing role in both our understanding of the normal functioning of the eye and in our ability to treat inherited eye disorders. This review summarises the mutations that have been associated with inherited eye disorders in the dog.
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33
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Miyadera K. Inherited retinal diseases in dogs: advances in gene/mutation discovery. DOBUTSU IDEN IKUSHU KENKYU = JOURNAL OF ANIMAL GENETICS 2014; 42:79-89. [PMID: 26120276 PMCID: PMC4480793 DOI: 10.5924/abgri.42.79] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
1. Inherited retinal diseases (RDs) are vision-threatening conditions affecting humans as well as many domestic animals. Through many years of clinical studies of the domestic dog population, a wide array of RDs has been phenotypically characterized. Extensive effort to map the causative gene and to identify the underlying mutation followed. Through candidate gene, linkage analysis, genome-wide association studies, and more recently, by means of next-generation sequencing, as many as 31 mutations in 24 genes have been identified as the underlying cause for canine RDs. Most of these genes have been associated with human RDs providing opportunities to study their roles in the disease pathogenesis and in normal visual function. The canine model has also contributed in developing new treatments such as gene therapy which has been clinically applied to human patients. Meanwhile, with increasing knowledge of the molecular architecture of RDs in different subpopulations of dogs, the conventional understanding of RDs as a simple monogenic disease is beginning to change. Emerging evidence of modifiers that alters the disease outcome is complicating the interpretation of DNA tests. In this review, advances in the gene/mutation discovery approaches and the emerging genetic complexity of canine RDs are discussed.
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Affiliation(s)
- Keiko Miyadera
- School of Veterinary Medicine, University of Pennsylvania, 3900 Delancey St, Philadelphia PA 19104 USA
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