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Ghiselli S, Parmeggiani G, Zambonini G, Cuda D. Hearing Loss in Baraitser-Winter Syndrome: Case Reports and Review of the Literature. J Clin Med 2024; 13:1500. [PMID: 38592426 PMCID: PMC10935159 DOI: 10.3390/jcm13051500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Revised: 03/01/2024] [Accepted: 03/02/2024] [Indexed: 04/10/2024] Open
Abstract
Background: Baraitser-Winter Syndrome (BRWS) is a rare autosomal dominant condition associated with hearing loss (HL). In the literature, two types of this condition are reported, Baraitser-Winter type 1 (BRWS1) and type 2 (BRWS2) produced by specific pathogenetic variants of two different genes, ACTB for BRWS1 and ACTG1 for BRWS2. In addition to syndromic BRWS2, some pathogenic variants in ACTG1 are associated also to another pathologic entity, the "Autosomal dominant non-syndromic hearing loss 20/26". In these syndromes, typical craniofacial features, sensory impairment (vision and hearing) and intellectual disabilities are frequently present. Heart anomalies, renal and gastrointestinal involvement and seizure are also common. Wide inter- and intra-familial variety in the phenotypic spectrum is reported. Some phenotypic aspects of these syndromes are not yet fully described, such as the degree and progression of HL, and better knowledge of them could be useful for correct follow-up and treatment. Methods and Results: In this study, we report two cases of children with HL and diagnosis of BRWS and a review of the current literature on HL in these syndromes.
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Affiliation(s)
- Sara Ghiselli
- Department of Otorhinolaryngology, AUSL Piacenza, 29121 Piacenza, Italy; (G.Z.); (D.C.)
| | | | - Giulia Zambonini
- Department of Otorhinolaryngology, AUSL Piacenza, 29121 Piacenza, Italy; (G.Z.); (D.C.)
| | - Domenico Cuda
- Department of Otorhinolaryngology, AUSL Piacenza, 29121 Piacenza, Italy; (G.Z.); (D.C.)
- Department of Medicine and Surgery, University of Parma, 43121 Parma, Italy
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2
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Graziani L, Cinnirella G, Ferradini V, Conte C, Bascio FL, Bengala M, Sangiuolo F, Novelli G. A likely pathogenic ACTG1 variant in a child showing partial phenotypic overlap with Baraitser-Winter syndrome. Am J Med Genet A 2023; 191:1565-1569. [PMID: 36810952 DOI: 10.1002/ajmg.a.63157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 12/16/2022] [Accepted: 02/08/2023] [Indexed: 02/23/2023]
Abstract
Baraitser-Winter syndrome (BRWS) is a rare autosomal dominant disease (AD) caused by heterozygous variants in ACTB (BRWS1) or ACTG1 (BRWS2) genes. BRWS features developmental delay/intellectual disability of variable degree and craniofacial dysmorphisms. Brain abnormalities (especially pachygyria), microcephaly, epilepsy, as well as hearing impairment, cardiovascular and genitourinary abnormalities may be present. We report on a 4-year-old female, who was addressed to our institution because of psychomotor delay associated with microcephaly and dysmorphic features, short stature, mild bilateral sensorineural hearing loss, mild cardiac septal hypertrophy, and abdominal swelling. Clinical exome sequencing detected a c.617G>A p.(Arg206Gln) de novo variant in ACTG1 gene. Such variant has been previously reported in association with a form of AD nonsyndromic sensorineural progressive hearing loss and we classified it as likely pathogenic according to ACMG/AMP criteria, despite our patient's phenotype only partially overlapped BWRS2. Our finding supports the extreme variability of the ACTG1-related disorders, ranging from classical BRWS2 to nuanced clinical expressions not fitting the original description, and occasionally featuring previously undescribed clinical findings.
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Affiliation(s)
- Ludovico Graziani
- Department of Biomedicine and Prevention, University of Rome "Tor Vergata", Rome, Italy
| | - Giacomo Cinnirella
- Department of Biomedicine and Prevention, University of Rome "Tor Vergata", Rome, Italy
| | - Valentina Ferradini
- Department of Biomedicine and Prevention, University of Rome "Tor Vergata", Rome, Italy
| | - Chiara Conte
- Tor Vergata University Hospital, Medical Genetics Unit, Rome, Italy
| | - Federica Lo Bascio
- Department of Biomedicine and Prevention, University of Rome "Tor Vergata", Rome, Italy
| | - Mario Bengala
- Tor Vergata University Hospital, Medical Genetics Unit, Rome, Italy
| | - Federica Sangiuolo
- Department of Biomedicine and Prevention, University of Rome "Tor Vergata", Rome, Italy.,Tor Vergata University Hospital, Medical Genetics Unit, Rome, Italy
| | - Giuseppe Novelli
- Department of Biomedicine and Prevention, University of Rome "Tor Vergata", Rome, Italy.,Tor Vergata University Hospital, Medical Genetics Unit, Rome, Italy
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3
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Nie K, Huang J, Liu L, Lv H, Chen D, Fan W. Identification of a De Novo Heterozygous Missense ACTB Variant in Baraitser–Winter Cerebrofrontofacial Syndrome. Front Genet 2022; 13:828120. [PMID: 35401677 PMCID: PMC8989421 DOI: 10.3389/fgene.2022.828120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 02/23/2022] [Indexed: 11/21/2022] Open
Abstract
Baraitser–Winter cerebrofrontofacial syndrome (BWCFF, OMIM: 243310) is a rare autosomal-dominant developmental disorder associated with variants in the genes ACTB or ACTG1. It is characterized by brain malformations, a distinctive facial appearance, ocular coloboma, and intellectual disability. However, the phenotypes of BWCFF are heterogenous, and its molecular pathogenesis has not been fully elucidated. In the present study, we conducted detailed clinical examinations on a Chinese patient with BWCFF and found novel ocular manifestations including pseudoduplication of the optic disc and nystagmus. Targeted gene panel sequencing and Sanger sequencing identified a de novo heterozygous missense c.478A > G (p.Thr160Ala) variant in ACTB. The mRNA and protein expression of ACTB was assessed by quantitative reverse transcription PCR and Western blots. Furthermore, the functional effects of the pathogenic variant were analyzed by protein structure analysis, which indicated that the variant may affect the active site for ATP hydrolysis by the actin ATPase, resulting in abnormal filamentous actin organization in peripheral blood mononuclear cells. This discovery extends the ACTB variant spectrum, which will improve genetic counseling and diagnosis, and may contribute to understanding the pathogenic mechanisms of actin-related diseases.
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Affiliation(s)
- Kailai Nie
- Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
- Research Laboratory of Ophthalmology and Vision Sciences, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Junting Huang
- Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
| | - Longqian Liu
- Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
| | - Hongbin Lv
- Department of Ophthalmology, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Danian Chen
- Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
- Research Laboratory of Ophthalmology and Vision Sciences, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
- *Correspondence: Wei Fan, ; Danian Chen,
| | - Wei Fan
- Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
- *Correspondence: Wei Fan, ; Danian Chen,
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4
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De Novo ACTG1 Variant Expands the Phenotype and Genotype of Partial Deafness and Baraitser-Winter Syndrome. Int J Mol Sci 2022; 23:ijms23020692. [PMID: 35054877 PMCID: PMC8776155 DOI: 10.3390/ijms23020692] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 01/02/2022] [Accepted: 01/05/2022] [Indexed: 02/04/2023] Open
Abstract
Actin molecules are fundamental for embryonic structural and functional differentiation; γ-actin is specifically required for the maintenance and function of cytoskeletal structures in the ear, resulting in hearing. Baraitser–Winter Syndrome (B-WS, OMIM #243310, #614583) is a rare, multiple-anomaly genetic disorder caused by mutations in either cytoplasmically expressed actin gene, ACTB (β-actin) or ACTG1 (γ-actin). The resulting actinopathies cause characteristic cerebrofrontofacial and developmental traits, including progressive sensorineural deafness. Both ACTG1-related non-syndromic A20/A26 deafness and B-WS diagnoses are characterized by hypervariable penetrance in phenotype. Here, we identify a 28th patient worldwide carrying a mutated γ-actin ACTG1 allele, with mildly manifested cerebrofrontofacial B-WS traits, hypervariable penetrance of developmental traits and sensorineural hearing loss. This patient also displays brachycephaly and a complete absence of speech faculty, previously unreported for ACTG1-related B-WS or DFNA20/26 deafness, representing phenotypic expansion. The patient’s exome sequence analyses (ES) confirms a de novo ACTG1 variant previously unlinked to the pathology. Additional microarray analysis uncover no further mutational basis for dual molecular diagnosis in our patient. We conclude that γ-actin c.542C > T, p.Ala181Val is a dominant pathogenic variant, associated with mildly manifested facial and cerebral traits typical of B-WS, hypervariable penetrance of developmental traits and sensorineural deafness. We further posit and present argument and evidence suggesting ACTG1-related non-syndromic DFNA20/A26 deafness is a manifestation of undiagnosed ACTG1-related B-WS.
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DFNA20/26 and Other ACTG1-Associated Phenotypes: A Case Report and Review of the Literature. Audiol Res 2021; 11:582-593. [PMID: 34698053 PMCID: PMC8544197 DOI: 10.3390/audiolres11040052] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 10/10/2021] [Accepted: 10/13/2021] [Indexed: 02/08/2023] Open
Abstract
Since the early 2000s, an ever-increasing subset of missense pathogenic variants in the ACTG1 gene has been associated with an autosomal-dominant, progressive, typically post-lingual non-syndromic hearing loss (NSHL) condition designed as DFNA20/26. ACTG1 gene encodes gamma actin, the predominant actin protein in the cytoskeleton of auditory hair cells; its normal expression and function are essential for the stereocilia maintenance. Different gain-of-function pathogenic variants of ACTG1 have been associated with two major phenotypes: DFNA20/26 and Baraitser-Winter syndrome, a multiple congenital anomaly disorder. Here, we report a novel ACTG1 variant [c.625G>A (p. Val209Met)] in an adult patient with moderate-severe NSHL characterized by a downsloping audiogram. The patient, who had a clinical history of slowly progressive NSHL and tinnitus, was referred to our laboratory for the analysis of a large panel of NSHL-associated genes by next generation sequencing. An extensive review of previously reported ACTG1 variants and their associated phenotypes was also performed.
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Van Heurck R, Carminho-Rodrigues MT, Ranza E, Stafuzza C, Quteineh L, Gehrig C, Hammar E, Guipponi M, Abramowicz M, Senn P, Guinand N, Cao-Van H, Paoloni-Giacobino A. Benefits of Exome Sequencing in Children with Suspected Isolated Hearing Loss. Genes (Basel) 2021; 12:genes12081277. [PMID: 34440452 PMCID: PMC8391342 DOI: 10.3390/genes12081277] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 08/03/2021] [Accepted: 08/18/2021] [Indexed: 12/12/2022] Open
Abstract
Purpose: Hearing loss is characterized by an extensive genetic heterogeneity and remains a common disorder in children. Molecular diagnosis is of particular benefit in children, and permits the early identification of clinically-unrecognized hearing loss syndromes, which permits effective clinical management and follow-up, including genetic counselling. Methods: We performed whole-exome sequencing with the analysis of a panel of 189 genes associated with hearing loss in a prospective cohort of 61 children and 9 adults presenting mainly with isolated hearing loss. Results: The overall diagnostic rate using exome sequencing was 47.2% (52.5% in children; 22% in adults). In children with confirmed molecular results, 17/32 (53.2%) showed autosomal recessive inheritance patterns, 14/32 (43.75%) showed an autosomal dominant condition, and one case had X-linked hearing loss. In adults, the two patients showed an autosomal dominant inheritance pattern. Among the 32 children, 17 (53.1%) had nonsyndromic hearing loss and 15 (46.7%) had syndromic hearing loss. One adult was diagnosed with syndromic hearing loss and one with nonsyndromic hearing loss. The most common causative genes were STRC (5 cases), GJB2 (3 cases), COL11A1 (3 cases), and ACTG1 (3 cases). Conclusions: Exome sequencing has a high diagnostic yield in children with hearing loss and can reveal a syndromic hearing loss form before other organs/systems become involved, allowing the surveillance of unrecognized present and/or future complications associated with these syndromes.
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Affiliation(s)
- Roxane Van Heurck
- Division of Genetic Medicine, Geneva University Hospitals, 1205 Geneva, Switzerland; (R.V.H.); (M.T.C.-R.); (E.R.); (L.Q.); (C.G.); (E.H.); (M.G.); (M.A.)
| | - Maria Teresa Carminho-Rodrigues
- Division of Genetic Medicine, Geneva University Hospitals, 1205 Geneva, Switzerland; (R.V.H.); (M.T.C.-R.); (E.R.); (L.Q.); (C.G.); (E.H.); (M.G.); (M.A.)
| | - Emmanuelle Ranza
- Division of Genetic Medicine, Geneva University Hospitals, 1205 Geneva, Switzerland; (R.V.H.); (M.T.C.-R.); (E.R.); (L.Q.); (C.G.); (E.H.); (M.G.); (M.A.)
| | - Caterina Stafuzza
- Ear-Nose-Throat/Head and Neck Surgery Division, Geneva University Hospitals, 1205 Geneva, Switzerland; (C.S.); (P.S.); (N.G.); (H.C.-V.)
| | - Lina Quteineh
- Division of Genetic Medicine, Geneva University Hospitals, 1205 Geneva, Switzerland; (R.V.H.); (M.T.C.-R.); (E.R.); (L.Q.); (C.G.); (E.H.); (M.G.); (M.A.)
| | - Corinne Gehrig
- Division of Genetic Medicine, Geneva University Hospitals, 1205 Geneva, Switzerland; (R.V.H.); (M.T.C.-R.); (E.R.); (L.Q.); (C.G.); (E.H.); (M.G.); (M.A.)
| | - Eva Hammar
- Division of Genetic Medicine, Geneva University Hospitals, 1205 Geneva, Switzerland; (R.V.H.); (M.T.C.-R.); (E.R.); (L.Q.); (C.G.); (E.H.); (M.G.); (M.A.)
| | - Michel Guipponi
- Division of Genetic Medicine, Geneva University Hospitals, 1205 Geneva, Switzerland; (R.V.H.); (M.T.C.-R.); (E.R.); (L.Q.); (C.G.); (E.H.); (M.G.); (M.A.)
| | - Marc Abramowicz
- Division of Genetic Medicine, Geneva University Hospitals, 1205 Geneva, Switzerland; (R.V.H.); (M.T.C.-R.); (E.R.); (L.Q.); (C.G.); (E.H.); (M.G.); (M.A.)
| | - Pascal Senn
- Ear-Nose-Throat/Head and Neck Surgery Division, Geneva University Hospitals, 1205 Geneva, Switzerland; (C.S.); (P.S.); (N.G.); (H.C.-V.)
| | - Nils Guinand
- Ear-Nose-Throat/Head and Neck Surgery Division, Geneva University Hospitals, 1205 Geneva, Switzerland; (C.S.); (P.S.); (N.G.); (H.C.-V.)
| | - Helene Cao-Van
- Ear-Nose-Throat/Head and Neck Surgery Division, Geneva University Hospitals, 1205 Geneva, Switzerland; (C.S.); (P.S.); (N.G.); (H.C.-V.)
| | - Ariane Paoloni-Giacobino
- Division of Genetic Medicine, Geneva University Hospitals, 1205 Geneva, Switzerland; (R.V.H.); (M.T.C.-R.); (E.R.); (L.Q.); (C.G.); (E.H.); (M.G.); (M.A.)
- Correspondence:
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7
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ACTG1 regulates intervertebral disc degeneration via the NF-κB-p65 and Akt pathways. Biochem Biophys Res Commun 2021; 545:54-61. [PMID: 33545632 DOI: 10.1016/j.bbrc.2021.01.057] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 01/15/2021] [Accepted: 01/19/2021] [Indexed: 12/18/2022]
Abstract
ACTG1 is a member of the actin family but is not a muscle actin gene. The ACTG1 mutation leads to hearing loss in humans, and the knockdown of ACTG1 suppresses the proliferation and migration of tumor cells; however, its role in intervertebral disc degeneration (IDD) is yet unclear. Bioinformatics methods revealed that ACTG1 might be a hub gene in IDD. Furthermore, the expression ACTG1 in severely degenerated nucleus pulposus (NP) tissues (Pfirrmann grade IV and V) was low as compared to that in mildly degenerated samples (Pfirrmann grade II and III). Moreover, the ACTG1 level was negatively correlated with human disc degeneration grades. The low expression of ACTG1 is also found in degenerated NP tissues in the rat. To further explore the function of ACTG1 in IDD, the gene expression was depleted in human NP cells via siRNA transfection. The ablation of ACTG1 increased MMP3 expression but decreased the level of collagen II. Excessive apoptosis was observed in ACTG1 knockdown groups, indicating that the absence of ACTG1 exacerbated IDD. GO function and pathway enrichment analysis for differentially expressed genes (DEGs) of two microarray datasets (GSE56081 and GSE42611) indicated that inflammatory response plays a crucial role in IDD. Interestingly, in the protein-protein interaction (PPI) network, ACTG1 is connected to the proteins of inflammation-related pathways. Furthermore, ACTG1 knockdown upregulated P-P65 level but suppressed P-Akt expression. These data collectively demonstrated that ACTG1 regulated the development of IDD through the NF-κB-p65 and Akt pathways, and ACTG1 may be a novel marker and therapeutic target of IDD in the future.
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8
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Gavrilovici C, Jiang Y, Kiroski I, Teskey GC, Rho JM, Nguyen MD. Postnatal Role of the Cytoskeleton in Adult Epileptogenesis. Cereb Cortex Commun 2020; 1:tgaa024. [PMID: 32864616 PMCID: PMC7446231 DOI: 10.1093/texcom/tgaa024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 06/08/2020] [Accepted: 06/11/2020] [Indexed: 02/07/2023] Open
Abstract
Mutations in cytoskeletal proteins can cause early infantile and childhood epilepsies by misplacing newly born neurons and altering neuronal connectivity. In the adult epileptic brain, cytoskeletal disruption is often viewed as being secondary to aberrant neuronal activity and/or death, and hence simply represents an epiphenomenon. Here, we review the emerging evidence collected in animal models and human studies implicating the cytoskeleton as a potential causative factor in adult epileptogenesis. Based on the emerging evidence, we propose that cytoskeletal disruption may be an important pathogenic mechanism in the mature epileptic brain.
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Affiliation(s)
- Cezar Gavrilovici
- Departments of Neurosciences & Pediatrics, University of California San Diego, Rady Children’s Hospital San Diego, San Diego, CA 92123, USA
| | - Yulan Jiang
- Departments of Clinical Neurosciences, Cell Biology & Anatomy, and Biochemistry & Molecular Biology, Hotchkiss Brain Institute, Alberta Children Hospital Research Institute, University of Calgary, Calgary T2N 4N1, Canada
| | - Ivana Kiroski
- Departments of Clinical Neurosciences, Cell Biology & Anatomy, and Biochemistry & Molecular Biology, Hotchkiss Brain Institute, Alberta Children Hospital Research Institute, University of Calgary, Calgary T2N 4N1, Canada
| | - G Campbell Teskey
- Department of Cell Biology & Anatomy, Hotchkiss Brain Institute, Alberta Children Hospital Research Institute, University of Calgary, Calgary T2N 4N1, Canada
| | - Jong M Rho
- Departments of Neurosciences & Pediatrics, University of California San Diego, Rady Children’s Hospital San Diego, San Diego, CA 92123, USA
| | - Minh Dang Nguyen
- Departments of Clinical Neurosciences, Cell Biology & Anatomy, and Biochemistry & Molecular Biology, Hotchkiss Brain Institute, Alberta Children Hospital Research Institute, University of Calgary, Calgary T2N 4N1, Canada
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9
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Hampshire K, Martin PM, Carlston C, Slavotinek A. Baraitser-Winter cerebrofrontofacial syndrome: Report of two adult siblings. Am J Med Genet A 2020; 182:1923-1932. [PMID: 32506774 DOI: 10.1002/ajmg.a.61637] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 04/21/2020] [Accepted: 04/25/2020] [Indexed: 11/07/2022]
Abstract
Baraitser-Winter cerebrofrontofacial syndrome (BWCS) is a rare, autosomal dominant condition that is characterized by intellectual disability, distinctive craniofacial features, structural brain abnormalities, seizures, microcephaly, hearing loss, and ocular colobomas. The first three cases were described in 1988 by Baraitser and Winter and included two siblings and an unrelated third patient. Subsequently, causative missense variants in the ACTB and ACTG1 genes were identified, with de novo occurrence in patients with the condition. Herein, we describe two adult siblings who were born to unaffected parents and who were diagnosed with BWCS in their fourth and sixth decade of life following exome sequencing performed for intellectual disability. We review the literature reports of adult patients with BWCS to document the clinical features and phenotypic variability that can occur later in life. This is the first molecularly confirmed report of germline mosaicism in BWCS and one of only a few reports to describe two BWCS patients belonging to the same family.
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Affiliation(s)
- Karly Hampshire
- Division of Medical Genetics, Department of Pediatrics, University of California San Francisco, San Francisco, California, USA
| | - Pierre-Marie Martin
- Institute for Human Genetics, University of California San Francisco, San Francisco, California, USA
| | - Colleen Carlston
- Division of Medical Genetics, Department of Pediatrics, University of California San Francisco, San Francisco, California, USA
| | - Anne Slavotinek
- Division of Medical Genetics, Department of Pediatrics, University of California San Francisco, San Francisco, California, USA
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Stiff HA, Sloan-Heggen CM, Ko A, Pfeifer WL, Kolbe DL, Nishimura CJ, Frees KL, Booth KT, Wang D, Weaver AE, Azaiez H, Kamholz J, Smith RJH, Drack AV. Is it Usher syndrome? Collaborative diagnosis and molecular genetics of patients with visual impairment and hearing loss. Ophthalmic Genet 2020; 41:151-158. [PMID: 32281467 PMCID: PMC7489297 DOI: 10.1080/13816810.2020.1747088] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Revised: 03/04/2020] [Accepted: 03/22/2020] [Indexed: 12/20/2022]
Abstract
Background: Usher syndrome is the most common hereditary syndrome combining deafness and blindness. In the 2017 National Child Count of Children and Youth who are Deaf-Blind, Usher syndrome represented 329 of 10,000 children, but there were also at least 70 other etiologies of deaf-blindness documented. The purpose of this study was to analyze the work-up and ultimate diagnoses of 21 consecutive families who presented to the Genetic Eye-Ear Clinic (GEEC) at the University of Iowa. Our hypothesis was that most families referred to the GEEC would have initial and final diagnoses of Usher syndrome.Materials and Methods: Patients were identified through an IRB approved retrospective chart review of referrals to the GEEC between 2012 and 2019. Details about each patient's history, exam, and clinical and genetic work-up were recorded.Results: From 2012 to 2019, 21 families (25 patients) were referred to the collaborative GEEC. Overall molecular diagnostic rate in this cohort was 14/21 (67%). Evaluation resulted in a change of diagnosis in 11/21 (52%) families. Ultimately, there were eleven unique diagnoses including hereditary, non-hereditary, and independent causes of combined visual impairment and hearing loss. The most common diagnosis was Usher syndrome, which represented 6/21 (29%) families.Conclusions: Providing a correct diagnosis for patients with visual impairment and hearing loss can be challenging for clinicians and their patients, but it can greatly improve clinical care and outcomes. We recommend an algorithm that includes multidisciplinary collaboration, careful clinical evaluation, strategic molecular testing, and consideration of a broad differential diagnosis.
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Affiliation(s)
- Heather A Stiff
- Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, Iowa, USA
| | - Christina M Sloan-Heggen
- Molecular Otolaryngology and Renal Research Laboratories, Department of Otolaryngology, Head and Neck Surgery, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA
- Department of Molecular Physiology & Biophysics, University of Iowa College of Medicine, Iowa City, Iowa, USA
| | - Ashley Ko
- Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, Iowa, USA
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Wanda L Pfeifer
- Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, Iowa, USA
| | - Diana L Kolbe
- Molecular Otolaryngology and Renal Research Laboratories, Department of Otolaryngology, Head and Neck Surgery, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA
| | - Carla J Nishimura
- Molecular Otolaryngology and Renal Research Laboratories, Department of Otolaryngology, Head and Neck Surgery, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA
| | - Kathy L Frees
- Molecular Otolaryngology and Renal Research Laboratories, Department of Otolaryngology, Head and Neck Surgery, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA
| | - Kevin T Booth
- Molecular Otolaryngology and Renal Research Laboratories, Department of Otolaryngology, Head and Neck Surgery, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA
| | - Donghong Wang
- Molecular Otolaryngology and Renal Research Laboratories, Department of Otolaryngology, Head and Neck Surgery, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA
| | - Amy E Weaver
- Molecular Otolaryngology and Renal Research Laboratories, Department of Otolaryngology, Head and Neck Surgery, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA
| | - Hela Azaiez
- Molecular Otolaryngology and Renal Research Laboratories, Department of Otolaryngology, Head and Neck Surgery, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA
| | - John Kamholz
- Department of Neurology, University of Iowa, Iowa City, Iowa, USA
| | - Richard J H Smith
- Molecular Otolaryngology and Renal Research Laboratories, Department of Otolaryngology, Head and Neck Surgery, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA
- Department of Molecular Physiology & Biophysics, University of Iowa College of Medicine, Iowa City, Iowa, USA
| | - Arlene V Drack
- Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, Iowa, USA
- The University of Iowa Institute for Vision Research, Iowa City, Iowa, USA
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11
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Chacon-Camacho OF, Barragán-Arévalo T, Villarroel CE, Almanza-Monterrubio M, Zenteno JC. Previously undescribed phenotypic findings and novel ACTG1 gene pathogenic variants in Baraitser-Winter cerebrofrontofacial syndrome. Eur J Med Genet 2020; 63:103877. [PMID: 32028042 DOI: 10.1016/j.ejmg.2020.103877] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 11/11/2019] [Accepted: 02/01/2020] [Indexed: 10/25/2022]
Abstract
Baraitser-Winter cerebrofrontofacial syndrome is an autosomal dominant disease characterized by multiple congenital abnormalities and intellectual disability, which is caused by mutations in either the ACTB or ACTG1 genes. In this report, we described novel phenotypic findings in two Mexican patients with the disorder in whom two novel ACTG1 mutations (c.176A > G, p.Gln59Arg; and c.608C > T, p.Thr203Met) were identified.
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Affiliation(s)
- Oscar F Chacon-Camacho
- Department of Genetics, Institute of Ophthalmology "Conde de Valenciana", Mexico City, Mexico; Carrera de Médico Cirujano, Facultad de Estudios Superiores Iztacala, Universidad Nacional Autónoma de México, Tlalnepantla, Estado de México, Mexico
| | | | - Camilo E Villarroel
- Department of Human Genetics, National Institute of Pediatrics, Mexico City, Mexico
| | - Mónica Almanza-Monterrubio
- Department of Human Genetics, National Institute of Pediatrics, Mexico City, Mexico; Department of Strabismus, Institute of Ophthalmology "Conde de Valenciana", Mexico City, Mexico
| | - Juan Carlos Zenteno
- Department of Genetics, Institute of Ophthalmology "Conde de Valenciana", Mexico City, Mexico; Department of Biochemistry, Faculty of Medicine, National Autonomous University of Mexico, Mexico City, Mexico.
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Cabanillas R, Diñeiro M, Cifuentes GA, Castillo D, Pruneda PC, Álvarez R, Sánchez-Durán N, Capín R, Plasencia A, Viejo-Díaz M, García-González N, Hernando I, Llorente JL, Repáraz-Andrade A, Torreira-Banzas C, Rosell J, Govea N, Gómez-Martínez JR, Núñez-Batalla F, Garrote JA, Mazón-Gutiérrez Á, Costales M, Isidoro-García M, García-Berrocal B, Ordóñez GR, Cadiñanos J. Comprehensive genomic diagnosis of non-syndromic and syndromic hereditary hearing loss in Spanish patients. BMC Med Genomics 2018; 11:58. [PMID: 29986705 PMCID: PMC6038346 DOI: 10.1186/s12920-018-0375-5] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 06/14/2018] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND Sensorineural hearing loss (SNHL) is the most common sensory impairment. Comprehensive next-generation sequencing (NGS) has become the standard for the etiological diagnosis of early-onset SNHL. However, accurate selection of target genomic regions (gene panel/exome/genome), analytical performance and variant interpretation remain relevant difficulties for its clinical implementation. METHODS We developed a novel NGS panel with 199 genes associated with non-syndromic and/or syndromic SNHL. We evaluated the analytical sensitivity and specificity of the panel on 1624 known single nucleotide variants (SNVs) and indels on a mixture of genomic DNA from 10 previously characterized lymphoblastoid cell lines, and analyzed 50 Spanish patients with presumed hereditary SNHL not caused by GJB2/GJB6, OTOF nor MT-RNR1 mutations. RESULTS The analytical sensitivity of the test to detect SNVs and indels on the DNA mixture from the cell lines was > 99.5%, with a specificity > 99.9%. The diagnostic yield on the SNHL patients was 42% (21/50): 47.6% (10/21) with autosomal recessive inheritance pattern (BSND, CDH23, MYO15A, STRC [n = 2], USH2A [n = 3], RDX, SLC26A4); 38.1% (8/21) autosomal dominant (ACTG1 [n = 3; 2 de novo], CHD7, GATA3 [de novo], MITF, P2RX2, SOX10), and 14.3% (3/21) X-linked (COL4A5 [de novo], POU3F4, PRPS1). 46.9% of causative variants (15/32) were not in the databases. 28.6% of genetically diagnosed cases (6/21) had previously undetected syndromes (Barakat, Usher type 2A [n = 3] and Waardenburg [n = 2]). 19% of genetic diagnoses (4/21) were attributable to large deletions/duplications (STRC deletion [n = 2]; partial CDH23 duplication; RDX exon 2 deletion). CONCLUSIONS In the era of precision medicine, obtaining an etiologic diagnosis of SNHL is imperative. Here, we contribute to show that, with the right methodology, NGS can be transferred to the clinical practice, boosting the yield of SNHL genetic diagnosis to 50-60% (including GJB2/GJB6 alterations), improving diagnostic/prognostic accuracy, refining genetic and reproductive counseling and revealing clinically relevant undiagnosed syndromes.
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Affiliation(s)
- Rubén Cabanillas
- Instituto de Medicina Oncológica y Molecular de Asturias (IMOMA) S. A, Avda. Richard Grandío s/n, 33193, Oviedo, Spain.
| | - Marta Diñeiro
- Instituto de Medicina Oncológica y Molecular de Asturias (IMOMA) S. A, Avda. Richard Grandío s/n, 33193, Oviedo, Spain
| | - Guadalupe A Cifuentes
- Instituto de Medicina Oncológica y Molecular de Asturias (IMOMA) S. A, Avda. Richard Grandío s/n, 33193, Oviedo, Spain
| | - David Castillo
- Disease Research And Medicine (DREAMgenics) S. L., Oviedo, Spain
| | | | - Rebeca Álvarez
- Instituto de Medicina Oncológica y Molecular de Asturias (IMOMA) S. A, Avda. Richard Grandío s/n, 33193, Oviedo, Spain
| | - Noelia Sánchez-Durán
- Instituto de Medicina Oncológica y Molecular de Asturias (IMOMA) S. A, Avda. Richard Grandío s/n, 33193, Oviedo, Spain
| | - Raquel Capín
- Instituto de Medicina Oncológica y Molecular de Asturias (IMOMA) S. A, Avda. Richard Grandío s/n, 33193, Oviedo, Spain
| | - Ana Plasencia
- Hospital Universitario Central de Asturias, Oviedo, Spain
| | | | | | - Inés Hernando
- Hospital Universitario Central de Asturias, Oviedo, Spain
| | | | | | | | - Jordi Rosell
- Hospital Universitario Son Espases, Palma de Mallorca, Spain
| | - Nancy Govea
- Hospital Universitario Son Espases, Palma de Mallorca, Spain
| | | | | | | | | | - María Costales
- Hospital Universitario Central de Asturias, Oviedo, Spain.,Hospital Universitario Marqués de Valdecilla, Santander, Spain
| | | | | | | | - Juan Cadiñanos
- Instituto de Medicina Oncológica y Molecular de Asturias (IMOMA) S. A, Avda. Richard Grandío s/n, 33193, Oviedo, Spain.
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Vedula P, Kashina A. The makings of the 'actin code': regulation of actin's biological function at the amino acid and nucleotide level. J Cell Sci 2018; 131:131/9/jcs215509. [PMID: 29739859 DOI: 10.1242/jcs.215509] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The actin cytoskeleton plays key roles in every eukaryotic cell and is essential for cell adhesion, migration, mechanosensing, and contractility in muscle and non-muscle tissues. In higher vertebrates, from birds through to mammals, actin is represented by a family of six conserved genes. Although these genes have evolved independently for more than 100 million years, they encode proteins with ≥94% sequence identity, which are differentially expressed in different tissues, and tightly regulated throughout embryogenesis and adulthood. It has been previously suggested that the existence of such similar actin genes is a fail-safe mechanism to preserve the essential function of actin through redundancy. However, knockout studies in mice and other organisms demonstrate that the different actins have distinct biological roles. The mechanisms maintaining this distinction have been debated in the literature for decades. This Review summarizes data on the functional regulation of different actin isoforms, and the mechanisms that lead to their different biological roles in vivo We focus here on recent studies demonstrating that at least some actin functions are regulated beyond the amino acid level at the level of the actin nucleotide sequence.
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Affiliation(s)
- Pavan Vedula
- Department of Biomedical Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Anna Kashina
- Department of Biomedical Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA
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Variations in Multiple Syndromic Deafness Genes Mimic Non-syndromic Hearing Loss. Sci Rep 2016; 6:31622. [PMID: 27562378 PMCID: PMC4999867 DOI: 10.1038/srep31622] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Accepted: 07/20/2016] [Indexed: 12/18/2022] Open
Abstract
The genetics of both syndromic (SHL) and non-syndromic hearing loss (NSHL) is characterized by a high degree of genetic heterogeneity. We analyzed whole exome sequencing data of 102 unrelated probands with apparently NSHL without a causative variant in known NSHL genes. We detected five causative variants in different SHL genes (SOX10, MITF, PTPN11, CHD7, and KMT2D) in five (4.9%) probands. Clinical re-evaluation of these probands shows that some of them have subtle syndromic findings, while none of them meets clinical criteria for the diagnosis of the associated syndrome (Waardenburg (SOX10 and MITF), Kallmann (CHD7 and SOX10), Noonan/LEOPARD (PTPN11), CHARGE (CHD7), or Kabuki (KMT2D). This study demonstrates that individuals who are evaluated for NSHL can have pathogenic variants in SHL genes that are not usually considered for etiologic studies.
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Abstract
Actin is the central building block of the actin cytoskeleton, a highly regulated filamentous network enabling dynamic processes of cells and simultaneously providing structure. Mammals have six actin isoforms that are very conserved and thus share common functions. Tissue-specific expression in part underlies their differential roles, but actin isoforms also coexist in various cell types and tissues, suggesting specific functions and preferential interaction partners. Gene deletion models, antibody-based staining patterns, gene silencing effects, and the occurrence of isoform-specific mutations in certain diseases have provided clues for specificity on the subcellular level and its consequences on the organism level. Yet, the differential actin isoform functions are still far from understood in detail. Biochemical studies on the different isoforms in pure form are just emerging, and investigations in cells have to deal with a complex and regulated system, including compensatory actin isoform expression.
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Affiliation(s)
- Christophe Ampe
- Department of Biochemistry, Faculty of Medicine and Health Sciences, Ghent University, A. Baertsoenkaai 3, 9000, Ghent, Belgium.
| | - Marleen Van Troys
- Department of Biochemistry, Faculty of Medicine and Health Sciences, Ghent University, A. Baertsoenkaai 3, 9000, Ghent, Belgium
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