1
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Boussaty EC, Friedman RA, Clifford RE. Hearing loss and tinnitus: association studies for complex-hearing disorders in mouse and man. Hum Genet 2022; 141:981-990. [PMID: 34318347 PMCID: PMC8792513 DOI: 10.1007/s00439-021-02317-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 07/13/2021] [Indexed: 12/29/2022]
Abstract
Genome-wide association studies (GWAS) provide an unbiased first look at genetic loci involved in aging and noise-induced sensorineural hearing loss and tinnitus. The hearing phenotype, whether audiogram-based or self-report, is regressed against genotyped information at representative single nucleotide polymorphisms (SNPs) across the genome. Findings include the fact that both hearing loss and tinnitus are polygenic disorders, with up to thousands of genes, each of effect size of < 0.02. Smaller human GWAS' were able to use objective measures and identified a few loci; however, hundreds of thousands of participants have been required for the statistical power to identify significant variants, and GWAS is unable to assess rare variants with mean allele frequency < 1%. Animal studies are required as well because of inability to access the human cochlea. Mouse GWAS builds on linkage techniques and the known phenotypic differences in auditory function between inbred strains. With the advantage that the laboratory environment can be controlled for noise and aging, the Hybrid Mouse Diversity Panel (HDMP) combines 100 strains sequenced at high resolution. Lift-over regions between mice and humans have identified over 17,000 homologous genes. Since most significant SNPs are either intergenic or in introns, and binding sites between species are poorly preserved between species, expression quantitative trait locus information is required to bring humans and mice into agreement. Transcriptome-wide analysis studies (TWAS) can prioritize putative causal genes and tissues. Diverse species, each making a distinct contribution, carry a synergistic advantage in the quest for treatment and ultimate cure of sensorineural hearing difficulties.
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Affiliation(s)
- Ely Cheikh Boussaty
- School of Health Sciences, Division of Otolaryngology, University of California San Diego, La Jolla, San Diego, CA, USA
| | - Rick Adam Friedman
- School of Health Sciences, Division of Otolaryngology, University of California San Diego, La Jolla, San Diego, CA, USA
| | - Royce E Clifford
- School of Health Sciences, Division of Otolaryngology, University of California San Diego, La Jolla, San Diego, CA, USA.
- Research Department, VA Hospitals San Diego, San Diego, CA, USA.
- Visiting Scientist, Department of Environmental Health, Harvard School of Public Health, Boston, MA, USA.
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2
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Imtiaz A, Belyantseva IA, Beirl AJ, Fenollar-Ferrer C, Bashir R, Bukhari I, Bouzid A, Shaukat U, Azaiez H, Booth KT, Kahrizi K, Najmabadi H, Maqsood A, Wilson EA, Fitzgerald TS, Tlili A, Olszewski R, Lund M, Chaudhry T, Rehman AU, Starost MF, Waryah AM, Hoa M, Dong L, Morell RJ, Smith RJH, Riazuddin S, Masmoudi S, Kindt KS, Naz S, Friedman TB. CDC14A phosphatase is essential for hearing and male fertility in mouse and human. Hum Mol Genet 2019; 27:780-798. [PMID: 29293958 DOI: 10.1093/hmg/ddx440] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Accepted: 12/21/2017] [Indexed: 12/31/2022] Open
Abstract
The Cell Division-Cycle-14 gene encodes a dual-specificity phosphatase necessary in yeast for exit from mitosis. Numerous disparate roles of vertebrate Cell Division-Cycle-14 (CDC14A) have been proposed largely based on studies of cultured cancer cells in vitro. The in vivo functions of vertebrate CDC14A are largely unknown. We generated and analyzed mutations of zebrafish and mouse CDC14A, developed a computational structural model of human CDC14A protein and report four novel truncating and three missense alleles of CDC14A in human families segregating progressive, moderate-to-profound deafness. In five of these families segregating pathogenic variants of CDC14A, deaf males are infertile, while deaf females are fertile. Several recessive mutations of mouse Cdc14a, including a CRISPR/Cas9-edited phosphatase-dead p.C278S substitution, result in substantial perinatal lethality, but survivors recapitulate the human phenotype of deafness and male infertility. CDC14A protein localizes to inner ear hair cell kinocilia, basal bodies and sound-transducing stereocilia. Auditory hair cells of postnatal Cdc14a mutants develop normally, but subsequently degenerate causing deafness. Kinocilia of germ-line mutants of mouse and zebrafish have normal lengths, which does not recapitulate the published cdc14aa knockdown morphant phenotype of short kinocilia. In mutant male mice, degeneration of seminiferous tubules and spermiation defects result in low sperm count, and abnormal sperm motility and morphology. These findings for the first time define a new monogenic syndrome of deafness and male infertility revealing an absolute requirement in vivo of vertebrate CDC14A phosphatase activity for hearing and male fertility.
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Affiliation(s)
- Ayesha Imtiaz
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, NIH, Bethesda, MD 20892, USA.,School of Biological Sciences, University of the Punjab, Lahore 54590, Pakistan
| | - Inna A Belyantseva
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, NIH, Bethesda, MD 20892, USA
| | - Alisha J Beirl
- Section on Sensory Cell Development and Function, National Institute on Deafness and Other Communication Disorders, NIH, Bethesda, MD 20892, USA
| | - Cristina Fenollar-Ferrer
- Laboratory of Molecular and Cellular Neurobiology, Section on Molecular and Cellular Signaling, National Institute of Mental Health, NIH, Bethesda, MD 20892, USA
| | - Rasheeda Bashir
- School of Biological Sciences, University of the Punjab, Lahore 54590, Pakistan
| | - Ihtisham Bukhari
- School of Biological Sciences, University of the Punjab, Lahore 54590, Pakistan
| | - Amal Bouzid
- Laboratoire Procédés de Criblage Moléculaire et Cellulaire, Centre de Biotechnologie de Sfax, Université de Sfax, Sfax 3451, Tunisia
| | - Uzma Shaukat
- Center of Excellence in Molecular Biology, University of the Punjab, Lahore 54590, Pakistan
| | - Hela Azaiez
- Molecular Otolaryngology and Renal Research Laboratories, Department of Otolaryngology - Head and Neck Surgery, University of Iowa, Iowa City, 52242, IA, USA
| | - Kevin T Booth
- Molecular Otolaryngology and Renal Research Laboratories, Department of Otolaryngology - Head and Neck Surgery, University of Iowa, Iowa City, 52242, IA, USA.,The Interdisciplinary Graduate Program in Molecular Medicine, Carver College of Medicine, University of Iowa, Iowa City, 52242, IA, USA
| | - Kimia Kahrizi
- Genetics Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran 1987513834, Iran
| | - Hossein Najmabadi
- Genetics Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran 1987513834, Iran
| | - Azra Maqsood
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, NIH, Bethesda, MD 20892, USA.,School of Biological Sciences, University of the Punjab, Lahore 54590, Pakistan
| | - Elizabeth A Wilson
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, NIH, Bethesda, MD 20892, USA
| | | | - Abdelaziz Tlili
- Laboratoire Procédés de Criblage Moléculaire et Cellulaire, Centre de Biotechnologie de Sfax, Université de Sfax, Sfax 3451, Tunisia
| | - Rafal Olszewski
- Auditory Development and Restoration Program, National Institute on Deafness and Other Communication Disorders, NIH, Bethesda, MD 20892, USA
| | - Merete Lund
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, NIH, Bethesda, MD 20892, USA
| | - Taimur Chaudhry
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, NIH, Bethesda, MD 20892, USA
| | - Atteeq U Rehman
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, NIH, Bethesda, MD 20892, USA
| | - Matthew F Starost
- Division of Veterinary Resources, National Institutes of Health, Bethesda, MD 20892, USA
| | - Ali M Waryah
- Center of Excellence in Molecular Biology, University of the Punjab, Lahore 54590, Pakistan
| | - Michael Hoa
- Auditory Development and Restoration Program, National Institute on Deafness and Other Communication Disorders, NIH, Bethesda, MD 20892, USA
| | - Lijin Dong
- Genetic Engineering Core, National Eye Institute, NIH, Bethesda, MD 20892, USA
| | - Robert J Morell
- Genomics and Computational Biology Core, National Institute on Deafness and Other Communication Disorders, NIH, Bethesda, MD 20892, USA
| | - Richard J H Smith
- Molecular Otolaryngology and Renal Research Laboratories, Department of Otolaryngology - Head and Neck Surgery, University of Iowa, Iowa City, 52242, IA, USA.,The Interdisciplinary Graduate Program in Molecular Medicine, Carver College of Medicine, University of Iowa, Iowa City, 52242, IA, USA
| | - Sheikh Riazuddin
- Center of Excellence in Molecular Biology, University of the Punjab, Lahore 54590, Pakistan.,Pakistan Institute of Medical Sciences, Shaheed Zulfiqar Ali Bhutto Medical University, Islamabad 44000, Pakistan.,Laboratory for Research in Genetic Diseases, Burn Centre, Allama Iqbal Medical College, University of Health Sciences, Lahore 54590, Pakistan
| | - Saber Masmoudi
- Laboratoire Procédés de Criblage Moléculaire et Cellulaire, Centre de Biotechnologie de Sfax, Université de Sfax, Sfax 3451, Tunisia
| | - Katie S Kindt
- Section on Sensory Cell Development and Function, National Institute on Deafness and Other Communication Disorders, NIH, Bethesda, MD 20892, USA
| | - Sadaf Naz
- School of Biological Sciences, University of the Punjab, Lahore 54590, Pakistan
| | - Thomas B Friedman
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, NIH, Bethesda, MD 20892, USA
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3
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Nakanishi H, Kurima K, Pan B, Wangemann P, Fitzgerald TS, Géléoc GS, Holt JR, Griffith AJ. Tmc2 expression partially restores auditory function in a mouse model of DFNB7/B11 deafness caused by loss of Tmc1 function. Sci Rep 2018; 8:12125. [PMID: 30108230 PMCID: PMC6092339 DOI: 10.1038/s41598-018-29709-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 07/03/2018] [Indexed: 11/19/2022] Open
Abstract
Mouse Tmc1 and Tmc2 are required for sensory transduction in cochlear and vestibular hair cells. Homozygous Tmc1∆/∆ mice are deaf, Tmc2∆/∆ mice have normal hearing, and double homozygous Tmc1∆/∆; Tmc2∆/∆ mice have deafness and profound vestibular dysfunction. These phenotypes are consistent with their different spatiotemporal expression patterns. Tmc1 expression is persistent in cochlear and vestibular hair cells, whereas Tmc2 expression is transient in cochlear hair cells but persistent in vestibular hair cells. On the basis of these findings, we hypothesized that persistent Tmc2 expression in mature cochlear hair cells could restore auditory function in Tmc1∆/∆ mice. To express Tmc2 in mature cochlear hair cells, we generated a transgenic mouse line, Tg[PTmc1::Tmc2], in which Tmc2 cDNA is expressed under the control of the Tmc1 promoter. The Tg[PTmc1::Tmc2] transgene slightly but significantly restored hearing in young Tmc1∆/∆ mice, though hearing thresholds were elevated with age. The elevation of hearing thresholds was associated with deterioration of sensory transduction in inner hair cells and loss of outer hair cell function. Although sensory transduction was retained in outer hair cells, their stereocilia eventually degenerated. These results indicate distinct roles and requirements for Tmc1 and Tmc2 in mature cochlear hair cells.
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MESH Headings
- Animals
- Disease Models, Animal
- Hair Cells, Auditory/cytology
- Hair Cells, Auditory/metabolism
- Hair Cells, Auditory/pathology
- Hair Cells, Auditory/ultrastructure
- Hair Cells, Vestibular/metabolism
- Hearing Loss, Sensorineural/diagnosis
- Hearing Loss, Sensorineural/genetics
- Hearing Loss, Sensorineural/pathology
- Hearing Tests
- Homozygote
- Humans
- Mechanotransduction, Cellular
- Membrane Proteins/genetics
- Membrane Proteins/metabolism
- Mice
- Mice, Knockout
- Microscopy, Electron, Scanning
- Mutation
- Patch-Clamp Techniques
- Promoter Regions, Genetic/genetics
- Stereocilia/pathology
- Stereocilia/ultrastructure
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Affiliation(s)
- Hiroshi Nakanishi
- Otolaryngology Branch, National Institute on Deafness and Other Communication Disorders (NIDCD), NIH, Bethesda, Maryland, 20892, USA
| | - Kiyoto Kurima
- Otolaryngology Branch, National Institute on Deafness and Other Communication Disorders (NIDCD), NIH, Bethesda, Maryland, 20892, USA
| | - Bifeng Pan
- Departments of Otolaryngology and Neurology, F. M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, 02115, USA
| | - Philine Wangemann
- Anatomy and Physiology Department, Kansas State University, Manhattan, Kansas, 66506, USA
| | - Tracy S Fitzgerald
- Mouse Auditory Testing Core Facility, NIDCD, NIH, Bethesda, Maryland, 20892, USA
| | - Gwenaëlle S Géléoc
- Departments of Otolaryngology and Neurology, F. M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, 02115, USA
| | - Jeffrey R Holt
- Departments of Otolaryngology and Neurology, F. M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, 02115, USA
| | - Andrew J Griffith
- Otolaryngology Branch, National Institute on Deafness and Other Communication Disorders (NIDCD), NIH, Bethesda, Maryland, 20892, USA.
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4
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Abstract
Identifying genes and pathways that contribute to differences in neurobehavioural traits is a key goal in psychiatric research. Despite considerable success in identifying quantitative trait loci (QTLs) associated with behaviour in laboratory rodents, pinpointing the causal variants and genes is more challenging. For a long time, the main obstacle was the size of QTLs, which could encompass tens if not hundreds of genes. However, recent studies have exploited mouse and rat resources that allow mapping of phenotypes to narrow intervals, encompassing only a few genes. Here, we review these studies, showcase the rodent resources they have used and highlight the insights into neurobehavioural traits provided to date. We discuss what we see as the biggest challenge in the field - translating QTLs into biological knowledge by experimentally validating and functionally characterizing candidate genes - and propose that the CRISPR/Cas genome-editing system holds the key to overcoming this obstacle. Finally, we challenge traditional views on inbred versus outbred resources in the light of recent resource and technology developments.
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Affiliation(s)
- Amelie Baud
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Jonathan Flint
- Center for Neurobehavioral Genetics, Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, CA 90095-1761, USA
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5
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Ohlemiller KK, Jones SM, Johnson KR. Application of Mouse Models to Research in Hearing and Balance. J Assoc Res Otolaryngol 2016; 17:493-523. [PMID: 27752925 PMCID: PMC5112220 DOI: 10.1007/s10162-016-0589-1] [Citation(s) in RCA: 88] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Accepted: 09/15/2016] [Indexed: 01/10/2023] Open
Abstract
Laboratory mice (Mus musculus) have become the major model species for inner ear research. The major uses of mice include gene discovery, characterization, and confirmation. Every application of mice is founded on assumptions about what mice represent and how the information gained may be generalized. A host of successes support the continued use of mice to understand hearing and balance. Depending on the research question, however, some mouse models and research designs will be more appropriate than others. Here, we recount some of the history and successes of the use of mice in hearing and vestibular studies and offer guidelines to those considering how to apply mouse models.
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Affiliation(s)
- Kevin K Ohlemiller
- Department of Otolaryngology, Central Institute for the Deaf, Fay and Carl Simons Center for Hearing and Deafness, Washington University School of Medicine, 660 S. Euclid, Saint Louis, MO, 63110, USA.
| | - Sherri M Jones
- Department of Special Education and Communication Disorders, University of Nebraska-Lincoln, Lincoln, NE, 68583, USA
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6
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Dowell R, Odell A, Richmond P, Malmer D, Halper-Stromberg E, Bennett B, Larson C, Leach S, Radcliffe RA. Genome characterization of the selected long- and short-sleep mouse lines. Mamm Genome 2016; 27:574-586. [PMID: 27651241 PMCID: PMC5110614 DOI: 10.1007/s00335-016-9663-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Accepted: 08/22/2016] [Indexed: 01/29/2023]
Abstract
The Inbred Long- and Short-Sleep (ILS, ISS) mouse lines were selected for differences in acute ethanol sensitivity using the loss of righting response (LORR) as the selection trait. The lines show an over tenfold difference in LORR and, along with a recombinant inbred panel derived from them (the LXS), have been widely used to dissect the genetic underpinnings of acute ethanol sensitivity. Here we have sequenced the genomes of the ILS and ISS to investigate the DNA variants that contribute to their sensitivity difference. We identified ~2.7 million high-confidence SNPs and small indels and ~7000 structural variants between the lines; variants were found to occur in 6382 annotated genes. Using a hidden Markov model, we were able to reconstruct the genome-wide ancestry patterns of the eight inbred progenitor strains from which the ILS and ISS were derived, and found that quantitative trait loci that have been mapped for LORR were slightly enriched for DNA variants. Finally, by mapping and quantifying RNA-seq reads from the ILS and ISS to their strain-specific genomes rather than to the reference genome, we found a substantial improvement in a differential expression analysis between the lines. This work will help in identifying and characterizing the DNA sequence variants that contribute to the difference in ethanol sensitivity between the ILS and ISS and will also aid in accurate quantification of RNA-seq data generated from the LXS RIs.
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Affiliation(s)
- Robin Dowell
- BioFrontiers Institute, University of Colorado Boulder, Boulder, CO, 80309, USA. .,Department of Molecular, Cellular, and Developmental Biology, University of Colorado Boulder, Boulder, CO, 80309, USA. .,Department of Computer Science, University of Colorado Boulder, Boulder, CO, 80309, USA.
| | - Aaron Odell
- BioFrontiers Institute, University of Colorado Boulder, Boulder, CO, 80309, USA
| | - Phillip Richmond
- BioFrontiers Institute, University of Colorado Boulder, Boulder, CO, 80309, USA.,Department of Molecular, Cellular, and Developmental Biology, University of Colorado Boulder, Boulder, CO, 80309, USA
| | - Daniel Malmer
- Department of Computer Science, University of Colorado Boulder, Boulder, CO, 80309, USA
| | - Eitan Halper-Stromberg
- Center for Genes, Environment and Health, National Jewish Health, Denver, CO, 80206, USA
| | - Beth Bennett
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado, Aurora, CO, 80045, USA
| | - Colin Larson
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado, Aurora, CO, 80045, USA
| | - Sonia Leach
- Center for Genes, Environment and Health, National Jewish Health, Denver, CO, 80206, USA
| | - Richard A Radcliffe
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado, Aurora, CO, 80045, USA.
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7
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Ohlemiller KK, Kiener AL, Gagnon PM. QTL Mapping of Endocochlear Potential Differences between C57BL/6J and BALB/cJ mice. J Assoc Res Otolaryngol 2016; 17:173-94. [PMID: 26980469 DOI: 10.1007/s10162-016-0558-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Accepted: 02/25/2016] [Indexed: 12/18/2022] Open
Abstract
We reported earlier that the endocochlear potential (EP) differs between C57BL/6J (B6) and BALB/cJ (BALB) mice, being lower in BALBs by about 10 mV (Ohlemiller et al. Hear Res 220: 10-26, 2006). This difference corresponds to strain differences with respect to the density of marginal cells in cochlear stria vascularis. After about 1 year of age, BALB mice also tend toward EP reduction that correlates with further marginal cell loss. We therefore suggested that early sub-clinical features of the BALB stria vascularis may predispose these mice to a condition modeling Schuknecht's strial presbycusis. We further reported (Ohlemiller et al. J Assoc Res Otolaryngol 12: 45-58, 2011) that the acute effects of a 2-h 110 dB SPL noise exposure differ between B6 and BALB mice, such that the EP remains unchanged in B6 mice, but is reduced by 40-50 mV in BALBs. In about 25 % of BALBs, the EP does not completely recover, so that permanent EP reduction may contribute to noise-induced permanent threshold shifts in BALBs. To identify genes and alleles that may promote natural EP variation as well as noise-related EP reduction in BALB mice, we have mapped related quantitative trait loci (QTLs) using 12 recombinant inbred (RI) strains formed from B6 and BALB (CxB1-CxB12). EP and strial marginal cell density were measured in B6 mice, BALB mice, their F1 hybrids, and RI mice without noise exposure, and 1-3 h after broadband noise (4-45 kHz, 110 dB SPL, 2 h). For unexposed mice, the strain distribution patterns for EP and marginal cell density were used to generate preliminary QTL maps for both EP and marginal cell density. Six QTL regions were at least statistically suggestive, including a significant QTL for marginal cell density on chromosome 12 that overlapped a weak QTL for EP variation. This region, termed Maced (Marginal cell density QTL) supports the notion of marginal cell density as a genetically influenced contributor to natural EP variation. Candidate genes for Maced notably include Foxg1, Foxa1, Akap6, Nkx2-1, and Pax9. Noise exposure produced significant EP reductions in two RI strains as well as significant EP increases in two RI strains. QTL mapping of the EP in noise-exposed RI mice yielded four suggestive regions. Two of these overlapped with QTL regions we previously identified for noise-related EP reduction in CBA/J mice (Ohlemiller et al. Hear Res 260: 47-53, 2010) on chromosomes 5 and 18 (Nirep). The present map may narrow the Nirep interval to a ~10-Mb region of proximal Chr. 18 that includes Zeb1, Arhgap12, Mpp7, and Gjd4. This study marks the first exploration of natural gene variants that modulate the EP. Their orthologs may underlie some human hearing loss that originates in the lateral wall.
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Affiliation(s)
- Kevin K Ohlemiller
- Department of Otolaryngology, Central Institute for the Deaf at Washington University School of Medicine, Fay and Carl Simons Center for Hearing and Deafness, Washington University School of Medicine, 660 S. Euclid, St. Louis, MO, 63110, USA.
| | - Anna L Kiener
- Department of Speech and Hearing Science, Ohio State University, Columbus, OH, USA
| | - Patricia M Gagnon
- Department of Otolaryngology, Central Institute for the Deaf at Washington University School of Medicine, Fay and Carl Simons Center for Hearing and Deafness, Washington University School of Medicine, 660 S. Euclid, St. Louis, MO, 63110, USA
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8
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Ma Q, Grati M, Bai F, Pei J, Pei XH, Liu X. Rescue from early-onset hearing loss in a mouse model lacking the cyclin-dependent kinase inhibitor p19Ink4d. Cell Death Dis 2016; 7:e2131. [PMID: 26962681 PMCID: PMC4823939 DOI: 10.1038/cddis.2016.38] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Q Ma
- Department of Otolaryngology (D-48), University of Miami Miller School of Medicine, Miami, FL, USA
| | - M Grati
- Department of Otolaryngology (D-48), University of Miami Miller School of Medicine, Miami, FL, USA
| | - F Bai
- Molecular Oncology Program, Department of Surgery, University of Miami Miller School of Medicine, Miami, FL, USA
| | - J Pei
- Department of Otolaryngology (D-48), University of Miami Miller School of Medicine, Miami, FL, USA
| | - X-H Pei
- Molecular Oncology Program, Department of Surgery, University of Miami Miller School of Medicine, Miami, FL, USA
| | - X Liu
- Department of Otolaryngology (D-48), University of Miami Miller School of Medicine, Miami, FL, USA
- Department of Otolaryngology, Xiangya Hospital, Central South University, Changsha, China
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9
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Johnson KR, Longo-Guess CM, Gagnon LH. A QTL on Chr 5 modifies hearing loss associated with the fascin-2 variant of DBA/2J mice. Mamm Genome 2015; 26:338-47. [PMID: 26092689 DOI: 10.1007/s00335-015-9574-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Accepted: 06/02/2015] [Indexed: 12/16/2022]
Abstract
Inbred mouse strains serve as important models for human presbycusis or age-related hearing loss. We previously mapped a locus (ahl8) contributing to the progressive hearing loss of DBA/2J (D2) mice and later showed that a missense variant of the Fscn2 gene, unique to the D2 inbred strain, was responsible for the ahl8 effect. Although ahl8 can explain much of the hearing loss difference between C57BL/6J (B6) and D2 strain mice, other loci also contribute. Here, we present results of our linkage analyses to map quantitative trait loci (QTLs) that modify the severity of hearing loss associated with the D2 strain Fscn2 (ahl8) allele. We searched for modifier loci by analyzing 31 BXD recombinant inbred (RI) lines fixed for the predisposing D2-derived Fscn2 (ahl8/ahl8) genotype and found a statistically significant linkage association of threshold means with a QTL on Chr 5, which we designated M5ahl8. The highest association (LOD 4.6) was with markers at the 84-90 Mb position of Chr 5, which could explain about 46 % of the among-RI strain variation in auditory brainstem response (ABR) threshold means. The semidominant nature of the modifying effect of M5ahl8 on the Fscn2 (ahl8/ahl8) phenotype was demonstrated by analysis of a backcross involving D2 and B6.D2-Chr11D/LusJ strain mice. The Chr 5 map position of M5ahl8 and the D2 origin of its susceptibility allele correspond to Tmc1m4, a previously reported QTL that modifies outer hair cell degeneration in Tmc1 (Bth) mutant mice, suggesting that M5ahl8 and Tmc1m4 may represent the same gene affecting maintenance of stereocilia structure and function during aging.
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MESH Headings
- Aging/genetics
- Aging/metabolism
- Aging/pathology
- Alleles
- Animals
- Carrier Proteins/genetics
- Carrier Proteins/metabolism
- Chromosome Mapping
- Chromosomes, Mammalian/chemistry
- Disease Models, Animal
- Evoked Potentials, Auditory, Brain Stem
- Female
- Gene Expression
- Genetic Linkage
- Genetic Predisposition to Disease
- Genotype
- Hair Cells, Auditory, Outer/metabolism
- Hair Cells, Auditory, Outer/pathology
- Humans
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Inbred DBA
- Microfilament Proteins/genetics
- Microfilament Proteins/metabolism
- Phenotype
- Presbycusis/genetics
- Presbycusis/metabolism
- Presbycusis/pathology
- Quantitative Trait Loci
- Severity of Illness Index
- Species Specificity
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10
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Peguero B, Tempel BL. A Chromosome 17 Locus Engenders Frequency-Specific Non-Progressive Hearing Loss that Contributes to Age-Related Hearing Loss in Mice. J Assoc Res Otolaryngol 2015; 16:459-71. [PMID: 25940139 DOI: 10.1007/s10162-015-0519-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Accepted: 04/16/2015] [Indexed: 12/20/2022] Open
Abstract
The 129S6/SvEvTac (129S6) inbred mouse is known for its resistance to noise-induced hearing loss (NIHL). However, less is understood of its unique age-related hearing loss (AHL) phenotype and its potential relationship with the resistance to NIHL. Here, we studied the physiological characteristics of hearing loss in 129S6 and asked if noise resistance (NR) and AHL are genetically linked to the same chromosomal region. We used auditory brainstem response (ABR) and distortion product otoacoustic emissions (DPOAE) to examine hearing sensitivity between 1 and 13 months of age of recombinant-inbred (congenic) mice with an NR phenotype. We identified a region of proximal chromosome (Chr) 17 (D17Mit143-D17Mit100) that contributes to a sensory, non-progressive hearing loss (NPHL) affecting exclusively the high-frequencies (>24 kHz) and maps to the nr1 locus on Chr 17. ABR experiments showed that 129S6 and CBA/CaJ F1 (CBACa) hybrid mice exhibit normal hearing, indicating that the hearing loss in 129S6 mice is inherited recessively. An allelic complementation test between the 129S6 and 101/H (101H) strains did not rescue hearing loss, suggesting genetic allelism between the nphl and phl1 loci of these strains, respectively. The hybrids had a milder hearing loss than either parental strain, which indicate a possible interaction with other genes in the mouse background or a digenic interaction between different genes that reside in the same genomic region. Our study defines a locus for nphl on Chr 17 affecting frequencies greater than 24 kHz.
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Affiliation(s)
- Braulio Peguero
- The Virginia Merrill Bloedel Hearing Research Center, University of Washington, Box 357923, Seattle, WA, 98195, USA
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McLachlan SM, Aliesky H, Banuelos B, Magana J, Williams RW, Rapoport B. Immunoglobulin heavy chain variable region and major histocompatibility region genes are linked to induced graves' disease in females from two very large families of recombinant inbred mice. Endocrinology 2014; 155:4094-103. [PMID: 25051451 PMCID: PMC4164918 DOI: 10.1210/en.2014-1388] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Graves' hyperthyroidism is caused by antibodies to the TSH receptor (TSHR) that mimic thyroid stimulation by TSH. Stimulating TSHR antibodies and hyperthyroidism can be induced by immunizing mice with adenovirus expressing the human TSHR A-subunit. Prior analysis of induced Graves' disease in small families of recombinant inbred (RI) female mice demonstrated strong genetic control but did not resolve trait loci for TSHR antibodies or elevated serum T4. We investigated the genetic basis for induced Graves' disease in female mice of two large RI families and combined data with earlier findings to provide phenotypes for 178 genotypes. TSHR antibodies measured by inhibition of TSH binding to its receptor were highly significantly linked in the BXD set to the major histocompatibility region (chromosome 17), consistent with observations in 3 other RI families. In the LXS family, we detected linkage between T4 levels after TSHR-adenovirus immunization and the Ig heavy chain variable region (Igvh, chromosome 12). This observation is a key finding because components of the antigen binding region of Igs determine antibody specificity and have been previously linked to induced thyroid-stimulating antibodies. Data from the LXS family provide the first evidence in mice of a direct link between induced hyperthyroidism and Igvh genes. A role for major histocompatibility genes has now been established for genetic susceptibility to Graves' disease in both humans and mice. Future studies using arrays incorporating variation in the complex human Ig gene locus will be necessary to determine whether Igvh genes are also linked to Graves' disease in humans.
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Affiliation(s)
- Sandra M McLachlan
- Thyroid Autoimmune Disease Unit (S.M.M., H.A., B.B., J.M., B.R.), Cedars-Sinai Research Institute and UCLA School of Medicine, Los Angeles, California 90048; and Department of Anatomy and Neurobiology (R.W.W.), University of Tennessee Health-Science Center, Memphis, Tennessee 38163
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Morozko EL, Nishio A, Ingham NJ, Chandra R, Fitzgerald T, Martelletti E, Borck G, Wilson E, Riordan GP, Wangemann P, Forge A, Steel KP, Liddle RA, Friedman TB, Belyantseva IA. ILDR1 null mice, a model of human deafness DFNB42, show structural aberrations of tricellular tight junctions and degeneration of auditory hair cells. Hum Mol Genet 2014; 24:609-24. [PMID: 25217574 PMCID: PMC4291242 DOI: 10.1093/hmg/ddu474] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
In the mammalian inner ear, bicellular and tricellular tight junctions (tTJs) seal the paracellular space between epithelial cells. Tricellulin and immunoglobulin-like (Ig-like) domain containing receptor 1 (ILDR1, also referred to as angulin-2) localize to tTJs of the sensory and non-sensory epithelia in the organ of Corti and vestibular end organs. Recessive mutations of TRIC (DFNB49) encoding tricellulin and ILDR1 (DFNB42) cause human nonsyndromic deafness. However, the pathophysiology of DFNB42 deafness remains unknown. ILDR1 was recently reported to be a lipoprotein receptor mediating the secretion of the fat-stimulated cholecystokinin (CCK) hormone in the small intestine, while ILDR1 in EpH4 mouse mammary epithelial cells in vitro was shown to recruit tricellulin to tTJs. Here we show that two different mouse Ildr1 mutant alleles have early-onset severe deafness associated with a rapid degeneration of cochlear hair cells (HCs) but have a normal endocochlear potential. ILDR1 is not required for recruitment of tricellulin to tTJs in the cochlea in vivo; however, tricellulin becomes mislocalized in the inner ear sensory epithelia of ILDR1 null mice after the first postnatal week. As revealed by freeze-fracture electron microscopy, ILDR1 contributes to the ultrastructure of inner ear tTJs. Taken together, our data provide insight into the pathophysiology of human DFNB42 deafness and demonstrate that ILDR1 is crucial for normal hearing by maintaining the structural and functional integrity of tTJs, which are critical for the survival of auditory neurosensory HCs.
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Affiliation(s)
- Eva L Morozko
- National Institute on Deafness and Other Communication Disorders, Section on Human Genetics
| | - Ayako Nishio
- National Institute on Deafness and Other Communication Disorders, Molecular Biology and Genetics Section
| | - Neil J Ingham
- Wolfson Centre for Age-Related Diseases, King's College London, London SE1 1UL, UK
| | - Rashmi Chandra
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Tracy Fitzgerald
- National Institute on Deafness and Other Communication Disorders, Mouse Auditory Testing Core Facility, National Institutes of Health, Bethesda, MD 20892-3729, USA
| | - Elisa Martelletti
- Wolfson Centre for Age-Related Diseases, King's College London, London SE1 1UL, UK
| | - Guntram Borck
- Institute of Human Genetics, University of Ulm, Ulm 89081, Germany
| | - Elizabeth Wilson
- National Institute on Deafness and Other Communication Disorders, Section on Human Genetics
| | - Gavin P Riordan
- National Institute on Deafness and Other Communication Disorders, Section on Human Genetics
| | - Philine Wangemann
- Anatomy and Physiology Department, Kansas State University, Manhattan, KS 66506-5802, USA and
| | - Andrew Forge
- Centre for Auditory Research, University College London, London WC1X 8EE, UK
| | - Karen P Steel
- Wolfson Centre for Age-Related Diseases, King's College London, London SE1 1UL, UK
| | - Rodger A Liddle
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Thomas B Friedman
- National Institute on Deafness and Other Communication Disorders, Section on Human Genetics
| | - Inna A Belyantseva
- National Institute on Deafness and Other Communication Disorders, Section on Human Genetics
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Slc26a4-insufficiency causes fluctuating hearing loss and stria vascularis dysfunction. Neurobiol Dis 2014; 66:53-65. [PMID: 24561068 DOI: 10.1016/j.nbd.2014.02.002] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2014] [Revised: 02/03/2014] [Accepted: 02/10/2014] [Indexed: 12/13/2022] Open
Abstract
SLC26A4 mutations can cause a distinctive hearing loss phenotype with sudden drops and fluctuation in patients. Existing Slc26a4 mutant mouse lines have a profound loss of hearing and vestibular function, with severe inner ear malformations that do not model this human phenotype. In this study, we generated Slc26a4-insufficient mice by manipulation of doxycycline administration to a transgenic mouse line in which all Slc26a4 expression was under the control of doxycycline. Doxycycline was administered from conception to embryonic day 17.5, and then it was discontinued. Auditory brainstem response thresholds showed significant fluctuation of hearing loss from 1 through 3months of age. The endocochlear potential, which is required for inner ear sensory cell function, correlated with auditory brainstem response thresholds. We observed degeneration of stria vascularis intermediate cells, the cells that generate the endocochlear potential, but no other abnormalities within the cochlea. We conclude that fluctuations of hearing result from fluctuations of the endocochlear potential and stria vascularis dysfunction in Slc26a4-insufficient mouse ears. This model can now be used to test potential interventions to reduce or prevent sudden hearing loss or fluctuation in human patients. Our strategy to generate a hypomorphic mouse model utilizing the tet-on system will be applicable to other diseases in which a hypomorphic allele is needed to model the human phenotype.
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Kikkawa Y, Seki Y, Okumura K, Ohshiba Y, Miyasaka Y, Suzuki S, Ozaki M, Matsuoka K, Noguchi Y, Yonekawa H. Advantages of a mouse model for human hearing impairment. Exp Anim 2012; 61:85-98. [PMID: 22531723 DOI: 10.1538/expanim.61.85] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Hearing is a major factor in human quality of life. Mouse models are important tools for discovering the genes that are responsible for genetic hearing loss, and these models often allow the processes that regulate the onset of deafness in humans to be analyzed. Thus far, in the study of hearing and deafness, at least 400 mutants with hearing impairments have been identified in laboratory mouse populations. Analysis of through a combination of genetic, morphological, and physiological studies is revealing valuable insights into the ontogenesis, morphogenesis, and function of the mammalian ear. This review discusses the advantages of the mouse models of human hearing impairment and highlights the identification of the molecules required for stereocilia development in the inner ear hair cells by analysis of various mouse mutants.
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Affiliation(s)
- Yoshiaki Kikkawa
- Mammalian Genetics Project, Department of Genome Medicine, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
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Schacht J, Altschuler R, Burke DT, Chen S, Dolan D, Galecki AT, Kohrman D, Miller RA. Alleles that modulate late life hearing in genetically heterogeneous mice. Neurobiol Aging 2012; 33:1842.e15-29. [PMID: 22305187 DOI: 10.1016/j.neurobiolaging.2011.12.034] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Revised: 12/08/2011] [Accepted: 12/28/2011] [Indexed: 12/20/2022]
Abstract
A genetically heterogeneous population of mice was tested for hearing at 8, 18, and 22 months by auditory brainstem response (ABR), and genotyped at 128 markers to identify loci that modulate late life hearing loss. Half of the test mice were exposed to noise for 2 hours at age 20 months. Polymorphisms affecting hearing at 18 months were noted on chromosomes 2, 3, 7, 10, and 15. Most of these loci had effects only on responses to 48 kHz stimuli, but a subset also influenced the auditory brainstem response at lower frequencies. Loci on chromosomes 4, 10, 12, and 14 had significant effects on hearing at 22 months in noise-exposed mice, and loci on chromosomes 10 and 11 had effects on mice not exposed to noise. Outer hair cell loss was modulated by polymorphisms on chromosomes 10, 11, 12, 17, and 19. Resistance to age-related hearing loss is thus modulated by a set of genetic effects, some age-specific, some frequency specific, some dependent on prior exposure to noise, and some of which compromise survival of cochlear hair cells.
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Affiliation(s)
- Jochen Schacht
- Kresge Hearing Research Institute, Department of Otolaryngology, University of Michigan Medical School, Ann Arbor, MI, USA
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Choi BY, Kim HM, Ito T, Lee KY, Li X, Monahan K, Wen Y, Wilson E, Kurima K, Saunders TL, Petralia RS, Wangemann P, Friedman TB, Griffith AJ. Mouse model of enlarged vestibular aqueducts defines temporal requirement of Slc26a4 expression for hearing acquisition. J Clin Invest 2011; 121:4516-25. [PMID: 21965328 DOI: 10.1172/jci59353] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2011] [Accepted: 08/10/2011] [Indexed: 12/13/2022] Open
Abstract
Mutations in human SLC26A4 are a common cause of hearing loss associated with enlarged vestibular aqueducts (EVA). SLC26A4 encodes pendrin, an anion-base exchanger expressed in inner ear epithelial cells that secretes HCO3- into endolymph. Studies of Slc26a4-null mice indicate that pendrin is essential for inner ear development, but have not revealed whether pendrin is specifically necessary for homeostasis. Slc26a4-null mice are profoundly deaf, with severe inner ear malformations and degenerative changes that do not model the less severe human phenotype. Here, we describe studies in which we generated a binary transgenic mouse line in which Slc26a4 expression could be induced with doxycycline. The transgenes were crossed onto the Slc26a4-null background so that all functional pendrin was derived from the transgenes. Varying the temporal expression of Slc26a4 revealed that E16.5 to P2 was the critical interval in which pendrin was required for acquisition of normal hearing. Lack of pendrin during this period led to endolymphatic acidification, loss of the endocochlear potential, and failure to acquire normal hearing. Doxycycline initiation at E18.5 or discontinuation at E17.5 resulted in partial hearing loss approximating the human EVA auditory phenotype. These data collectively provide mechanistic insight into hearing loss caused by SLC26A4 mutations and establish a model for further studies of EVA-associated hearing loss.
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Affiliation(s)
- Byung Yoon Choi
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, NIH, Rockville, Maryland, USA
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Keller JM, Neely HR, Latoche JR, Noben-Trauth K. High-frequency sensorineural hearing loss and its underlying genetics (Hfhl1 and Hfhl2) in NIH Swiss mice. J Assoc Res Otolaryngol 2011; 12:617-31. [PMID: 21594677 PMCID: PMC3173551 DOI: 10.1007/s10162-011-0270-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2011] [Accepted: 04/25/2011] [Indexed: 11/12/2022] Open
Abstract
Studies using inbred strains of mice have been invaluable for identifying alleles that adversely affect hearing. However, the efficacy of those studies is limited by the phenotypes that these strains express and the alleles that they segregate. Here, by selectively breeding phenotypically and genetically heterogeneous NIH Swiss mice, we generated two lines—the all-frequency hearing loss (AFHL) line and the high-frequency hearing loss (HFHL) line—with differential hearing loss. The AFHL line exhibited characteristics typical of severe, early-onset, sensorineural hearing impairment. In contrast, the HFHL line expressed a novel early-onset, mildly progressive, and frequency-specific sensorineural hearing loss. By quantitative trait loci (QTLs) analyses in these two lines, we identified QTLs on chromosomes 7, 8, and 10 that significantly affected hearing function. The loci on chromosomes 7 and 8 (Hfhl1 and Hfhl2, respectively) are novel and appear to adversely affect only high frequencies (≥30 kHz). Mice homozygous for NIH Swiss alleles at either Hfhl1 or Hfhl2 have 32-kHz auditory-evoked brain stem response thresholds that are 8–14 dB SPL higher than the corresponding heterozygotes. DNA sequence analyses suggest that both the Cdh23ahl and Gipc3ahl5 variants contribute to the chromosome 10 QTL detected in the AFHL line. The frequency-specific hearing loss indicates that the Hfhl1 and Hfhl2 alleles may affect tonotopic development. In addition, dissecting the underlying complex genetics of high-frequency hearing loss may prove relevant in identifying less severe and common forms of hearing impairment in the human population.
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Affiliation(s)
- James M Keller
- Section on Neurogenetics, Laboratory of Molecular Biology, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Rockville, MD 20850, USA
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Mihaila C, Schramm J, Strathmann FG, Lee DL, Gelein RM, Luebke AE, Mayer-Pröschel M. Identifying a window of vulnerability during fetal development in a maternal iron restriction model. PLoS One 2011; 6:e17483. [PMID: 21423661 PMCID: PMC3057971 DOI: 10.1371/journal.pone.0017483] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2010] [Accepted: 02/07/2011] [Indexed: 11/19/2022] Open
Abstract
It is well acknowledged from observations in humans that iron deficiency during pregnancy can be associated with a number of developmental problems in the newborn and developing child. Due to the obvious limitations of human studies, the stage during gestation at which maternal iron deficiency causes an apparent impairment in the offspring remains elusive. In order to begin to understand the time window(s) during pregnancy that is/are especially susceptible to suboptimal iron levels, which may result in negative effects on the development of the fetus, we developed a rat model in which we were able to manipulate and monitor the dietary iron intake during specific stages of pregnancy and analyzed the developing fetuses. We established four different dietary-feeding protocols that were designed to render the fetuses iron deficient at different gestational stages. Based on a functional analysis that employed Auditory Brainstem Response measurements, we found that maternal iron restriction initiated prior to conception and during the first trimester were associated with profound changes in the developing fetus compared to iron restriction initiated later in pregnancy. We also showed that the presence of iron deficiency anemia, low body weight, and changes in core body temperature were not defining factors in the establishment of neural impairment in the rodent offspring.Our data may have significant relevance for understanding the impact of suboptimal iron levels during pregnancy not only on the mother but also on the developing fetus and hence might lead to a more informed timing of iron supplementation during pregnancy.
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Affiliation(s)
- Camelia Mihaila
- Department of Biomedical Genetics, University of Rochester, Rochester, New York, United States of America
| | - Jordan Schramm
- Department of Neurobiology and Anatomy, University of Rochester, Rochester, New York, United States of America
| | - Frederick G. Strathmann
- Department of Biomedical Genetics, University of Rochester, Rochester, New York, United States of America
| | - Dawn L. Lee
- Department of Pathology and Laboratory Medicine, University of Rochester, Rochester, New York, United States of America
| | - Robert M. Gelein
- Department of Environmental Medicine, University of Rochester, Rochester, New York, United States of America
| | - Anne E. Luebke
- Department of Neurobiology and Anatomy, University of Rochester, Rochester, New York, United States of America
- Department of Biomedical Engineering, University of Rochester, Rochester, New York, United States of America
- * E-mail: (MM-P); (AEL)
| | - Margot Mayer-Pröschel
- Department of Biomedical Genetics, University of Rochester, Rochester, New York, United States of America
- Department of Neurobiology and Anatomy, University of Rochester, Rochester, New York, United States of America
- * E-mail: (MM-P); (AEL)
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