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Scala M, Tomati V, Ferla M, Lena M, Cohen JS, Fatemi A, Brokamp E, Bican A, Phillips JA, Koziura ME, Nicouleau M, Rio M, Siquier K, Boddaert N, Musante I, Tamburro S, Baldassari S, Iacomino M, Scudieri P, Rosenfeld JA, Bellus G, Reed S, Al Saif H, Russo RS, Walsh MB, Cantagrel V, Crunk A, Gustincich S, Ruggiero SM, Fitzgerald MP, Helbig I, Striano P, Severino M, Salpietro V, Pedemonte N, Zara F. De novo variants in DENND5B cause a neurodevelopmental disorder. Am J Hum Genet 2024; 111:529-543. [PMID: 38387458 PMCID: PMC10940048 DOI: 10.1016/j.ajhg.2024.02.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 01/30/2024] [Accepted: 02/01/2024] [Indexed: 02/24/2024] Open
Abstract
The Rab family of guanosine triphosphatases (GTPases) includes key regulators of intracellular transport and membrane trafficking targeting specific steps in exocytic, endocytic, and recycling pathways. DENND5B (Rab6-interacting Protein 1B-like protein, R6IP1B) is the longest isoform of DENND5, an evolutionarily conserved DENN domain-containing guanine nucleotide exchange factor (GEF) that is highly expressed in the brain. Through exome sequencing and international matchmaking platforms, we identified five de novo variants in DENND5B in a cohort of five unrelated individuals with neurodevelopmental phenotypes featuring cognitive impairment, dysmorphism, abnormal behavior, variable epilepsy, white matter abnormalities, and cortical gyration defects. We used biochemical assays and confocal microscopy to assess the impact of DENND5B variants on protein accumulation and distribution. Then, exploiting fluorescent lipid cargoes coupled to high-content imaging and analysis in living cells, we investigated whether DENND5B variants affected the dynamics of vesicle-mediated intracellular transport of specific cargoes. We further generated an in silico model to investigate the consequences of DENND5B variants on the DENND5B-RAB39A interaction. Biochemical analysis showed decreased protein levels of DENND5B mutants in various cell types. Functional investigation of DENND5B variants revealed defective intracellular vesicle trafficking, with significant impairment of lipid uptake and distribution. Although none of the variants affected the DENND5B-RAB39A interface, all were predicted to disrupt protein folding. Overall, our findings indicate that DENND5B variants perturb intracellular membrane trafficking pathways and cause a complex neurodevelopmental syndrome with variable epilepsy and white matter involvement.
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Affiliation(s)
- Marcello Scala
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy; Pediatric Neurology and Muscular Diseases Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy; UOC Genetica Medica, IRCCS Giannina Gaslini, Genoa, Italy
| | - Valeria Tomati
- UOC Genetica Medica, IRCCS Giannina Gaslini, Genoa, Italy
| | - Matteo Ferla
- Oxford Protein Informatics Group, Department of Statistics, University of Oxford, Oxford, UK
| | - Mariateresa Lena
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy
| | - Julie S Cohen
- Department of Neurology and Developmental Medicine, Kennedy Krieger Institute, Baltimore, MD, USA; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Ali Fatemi
- Department of Neurology and Developmental Medicine, Kennedy Krieger Institute, Baltimore, MD, USA; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Elly Brokamp
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Anna Bican
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - John A Phillips
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Mary E Koziura
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Michael Nicouleau
- Université Paris Cité, Imagine Institute, Developmental Brain Disorders Laboratory, INSERM UMR 1163, 75015 Paris, France
| | - Marlene Rio
- Université Paris Cité, Imagine Institute, Developmental Brain Disorders Laboratory, INSERM UMR 1163, 75015 Paris, France; Service de Génétique, Necker Enfants Malades University Hospital, Assistance Publique-Hôpitaux de Pairs, Paris, France
| | - Karine Siquier
- Université Paris Cité, Imagine Institute, Developmental Brain Disorders Laboratory, INSERM UMR 1163, 75015 Paris, France
| | - Nathalie Boddaert
- Département de Radiologie Pédiatrique, INSERM UMR 1163 and INSERM U1000, AP-HP, Hôpital Necker-Enfants Malades, Paris, France
| | - Ilaria Musante
- UOC Genetica Medica, IRCCS Giannina Gaslini, Genoa, Italy
| | | | | | | | - Paolo Scudieri
- UOC Genetica Medica, IRCCS Giannina Gaslini, Genoa, Italy
| | - Jill A Rosenfeld
- Department of Molecular & Human Genetics, Baylor College of Medicine, Houston, TX, USA; Baylor Genetics Laboratories, Houston, TX, USA
| | - Gary Bellus
- Clinical Genetics, Geisinger Medical Center, Danville, PA 17822, USA
| | - Sara Reed
- Clinical Genetics, Geisinger Medical Center, Danville, PA 17822, USA
| | - Hind Al Saif
- Department of Human and Molecular Genetics, Division of Clinical Genetics, Virginia Commonwealth University School of Medicine, Richmond, VA, USA
| | | | - Matthew B Walsh
- Department of Human Genetics, Emory University, Atlanta, GA 30322, USA
| | - Vincent Cantagrel
- Université Paris Cité, Imagine Institute, Developmental Brain Disorders Laboratory, INSERM UMR 1163, 75015 Paris, France
| | | | - Stefano Gustincich
- Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, 16163 Genoa, Italy
| | - Sarah M Ruggiero
- Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA; The Epilepsy NeuroGenetics Initiative (ENGIN), Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Mark P Fitzgerald
- Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA; The Epilepsy NeuroGenetics Initiative (ENGIN), Children's Hospital of Philadelphia, Philadelphia, PA, USA; Department of Neurology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Ingo Helbig
- Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA; The Epilepsy NeuroGenetics Initiative (ENGIN), Children's Hospital of Philadelphia, Philadelphia, PA, USA; Department of Neurology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA 19104, USA; Department of Biomedical and Health Informatics (DBHi), Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Pasquale Striano
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy; Pediatric Neurology and Muscular Diseases Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | | | - Vincenzo Salpietro
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy; Pediatric Neurology and Muscular Diseases Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy.
| | | | - Federico Zara
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy; UOC Genetica Medica, IRCCS Giannina Gaslini, Genoa, Italy
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Brokamp E, Koziura ME, Phillips JA, Tang LA, Cogan JD, Rives LC, Robertson AK, Duncan L, Bican A, Peterson JF, Newman JH, Hamid R, Bastarache L. One is the loneliest number: genotypic matchmaking using the electronic health record. Genet Med 2021; 23:1830-1832. [PMID: 34230636 DOI: 10.1038/s41436-021-01179-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Accepted: 04/05/2021] [Indexed: 01/02/2023] Open
Affiliation(s)
- Elly Brokamp
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA.
| | - Mary E Koziura
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - John A Phillips
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Leigh Anne Tang
- Center for Precision Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Joy D Cogan
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Lynette C Rives
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Amy K Robertson
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Laura Duncan
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Anna Bican
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Josh F Peterson
- Center for Precision Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - John H Newman
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Rizwan Hamid
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Lisa Bastarache
- Center for Precision Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
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3
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Briere LC, Walker MA, High FA, Cooper C, Rogers CA, Callahan CJ, Ishimura R, Ichimura Y, Caruso PA, Sharma N, Brokamp E, Koziura ME, Mohammad SS, Dale RC, Riley LG, Phillips JA, Komatsu M, Sweetser DA. A description of novel variants and review of phenotypic spectrum in UBA5-related early epileptic encephalopathy. Cold Spring Harb Mol Case Stud 2021; 7:a005827. [PMID: 33811063 PMCID: PMC8208045 DOI: 10.1101/mcs.a005827] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 03/10/2021] [Indexed: 12/22/2022] Open
Abstract
Early infantile epileptic encephalopathy-44 (EIEE44, MIM: 617132) is a previously described condition resulting from biallelic variants in UBA5, a gene involved in a ubiquitin-like post-translational modification system called UFMylation. Here we report five children from four families with biallelic pathogenic variants in UBA5 All five children presented with global developmental delay, epilepsy, axial hypotonia, appendicular hypertonia, and a movement disorder, including dystonia in four. Affected individuals in all four families have compound heterozygous pathogenic variants in UBA5 All have the recurrent mild c.1111G > A (p.Ala371Thr) variant in trans with a second UBA5 variant. One patient has the previously described c.562C > T (p. Arg188*) variant, two other unrelated patients have a novel missense variant, c.907T > C (p.Cys303Arg), and the two siblings have a novel missense variant, c.761T > C (p.Leu254Pro). Functional analyses demonstrate that both the p.Cys303Arg variant and the p.Leu254Pro variants result in a significant decrease in protein function. We also review the phenotypes and genotypes of all 15 previously reported families with biallelic UBA5 variants, of which two families have presented with distinct phenotypes, and we describe evidence for some limited genotype-phenotype correlation. The overlap of motor and developmental phenotypes noted in our cohort and literature review adds to the increasing understanding of genetic syndromes with movement disorders-epilepsy.
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Affiliation(s)
- Lauren C Briere
- Department of Pediatrics, Division of Medical Genetics and Metabolism, and Center for Genomic Medicine, Massachusetts 02114, USA
| | - Melissa A Walker
- Department of Neurology, Division of Neurogenetics, Child Neurology, Massachusetts 02114, USA
| | - Frances A High
- Department of Pediatrics, Division of Medical Genetics and Metabolism, Massachusetts 02114, USA
| | - Cynthia Cooper
- Department of Internal Medicine, Massachusetts General Hospital, Boston, Massachusetts 02114, USA
| | - Cassandra A Rogers
- Department of Pediatrics, Division of Medical Genetics and Metabolism, and Center for Genomic Medicine, Massachusetts 02114, USA
| | - Christine J Callahan
- Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA
| | - Ryosuke Ishimura
- Department of Biochemistry, Niigata University School of Medical and Dental Sciences, Chuo-ku, Niigata 951-8510, Japan
| | - Yoshinobu Ichimura
- Department of Biochemistry, Niigata University School of Medical and Dental Sciences, Chuo-ku, Niigata 951-8510, Japan
| | - Paul A Caruso
- Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts 02114, USA
| | - Nutan Sharma
- Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts 02114, USA
| | - Elly Brokamp
- Division of Medical Genetics and Genomic Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, USA
| | - Mary E Koziura
- Division of Medical Genetics and Genomic Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, USA
| | - Shekeeb S Mohammad
- Kids Neuroscience Center & Children's Hospital at Westmead Clinical School, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Russell C Dale
- Kids Neuroscience Center & Children's Hospital at Westmead Clinical School, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Lisa G Riley
- Rare Diseases Functional Genomics, Kids Research, The Children's Hospital at Westmead and Children's Medical Research Institute, Westmead, New South Wales 2145, Australia
- Discipline of Child & Adolescent Health, University of Sydney, Sydney, New South Wales 2006, Australia
| | - John A Phillips
- Division of Medical Genetics and Genomic Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, USA
| | - Masaaki Komatsu
- Department of Biochemistry, Niigata University School of Medical and Dental Sciences, Chuo-ku, Niigata 951-8510, Japan
- Department of Physiology, Juntendo University School of Medicine, Tokyo 113-8421, Japan
| | - David A Sweetser
- Department of Pediatrics, Division of Medical Genetics and Metabolism, and Center for Genomic Medicine, Massachusetts 02114, USA
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4
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Burdick KJ, Cogan JD, Rives LC, Robertson AK, Koziura ME, Brokamp E, Duncan L, Hannig V, Pfotenhauer J, Vanzo R, Paul MS, Bican A, Morgan T, Duis J, Newman JH, Hamid R, Phillips JA. Limitations of exome sequencing in detecting rare and undiagnosed diseases. Am J Med Genet A 2020; 182:1400-1406. [PMID: 32190976 DOI: 10.1002/ajmg.a.61558] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 01/28/2020] [Accepted: 03/03/2020] [Indexed: 12/21/2022]
Abstract
While exome sequencing (ES) is commonly the final diagnostic step in clinical genetics, it may miss diagnoses. To clarify the limitations of ES, we investigated the diagnostic yield of genetic tests beyond ES in our Undiagnosed Diseases Network (UDN) participants. We reviewed the yield of additional genetic testing including genome sequencing (GS), copy number variant (CNV), noncoding variant (NCV), repeat expansion (RE), or methylation testing in UDN cases with nondiagnostic ES results. Overall, 36/54 (67%) of total diagnoses were based on clinical findings and coding variants found by ES and 3/54 (6%) were based on clinical findings only. The remaining 15/54 (28%) required testing beyond ES. Of these, 7/15 (47%) had NCV, 6/15 (40%) CNV, and 2/15 (13%) had a RE or a DNA methylation disorder. Thus 18/54 (33%) of diagnoses were not solved exclusively by ES. Several methods were needed to detect and/or confirm the functional effects of the variants missed by ES, and in some cases by GS. These results indicate that tests to detect elusive variants should be considered after nondiagnostic preliminary steps. Further studies are needed to determine the cost-effectiveness of tests beyond ES that provide diagnoses and insights to possible treatment.
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Affiliation(s)
- Kendall J Burdick
- University of Massachusetts of Medical School, Worcester, Massachusetts, USA
| | - Joy D Cogan
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Lynette C Rives
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Amy K Robertson
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Mary E Koziura
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Elly Brokamp
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Laura Duncan
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Vickie Hannig
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Jean Pfotenhauer
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Rena Vanzo
- Lineagen Inc., Salt Lake City, Utah, USA
| | | | - Anna Bican
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Thomas Morgan
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Jessica Duis
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - John H Newman
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Rizwan Hamid
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - John A Phillips
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, USA
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5
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Bhatia A, Mobley BC, Cogan J, Koziura ME, Brokamp E, Phillips J, Newman J, Moore SA, Hamid R. Magnetic Resonance Imaging characteristics in case of TOR1AIP1 muscular dystrophy. Clin Imaging 2019; 58:108-113. [PMID: 31299614 PMCID: PMC6893088 DOI: 10.1016/j.clinimag.2019.06.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2019] [Revised: 05/24/2019] [Accepted: 06/18/2019] [Indexed: 11/19/2022]
Abstract
Mutations in the torsinA-interacting protein 1 (TOR1AIP1) gene result in a severe muscular dystrophy with minimal literature in the pediatric population. We review a case of TOR1AIP1 gene mutation in a 16-year-old Caucasian female with a long history of muscle weakness. Extensive clinical workup was performed and MRI at time of initial presentation demonstrated no significant muscular atrophy with heterogenous STIR hyperintensity of the lower extremity muscles. MRI findings seven years later included extensive atrophy of the lower extremities, with severe progression, including the gluteal muscles, iliopsoas, rectus femoris, and obturator internus. There was also significant atrophy of the rectus abdominis and internal and external oblique muscles, and iliacus muscles. The MRI findings showed more proximal involvement of lower extremities and no atrophy of the tibialis anterior, making TOR1AIP1 the more likely genetic cause. Muscle biopsy findings supported TOR1AIP1 limb-girdle muscular dystrophy. Though rare, TOR1AIP1 gene mutation occurs in pediatric patients and MRI can aid in diagnosis and help differentiate from other types of muscular dystrophy. Genetic and pathology workup is also crucial to accurate diagnosis and possible treatment of these patients.
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Affiliation(s)
- Aashim Bhatia
- Department of Radiology, Vanderbilt University Medical Center, Nashville, TN, USA.
| | - Bret C Mobley
- Pathology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Joy Cogan
- Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Mary E Koziura
- Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Elly Brokamp
- Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - John Phillips
- Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - John Newman
- Internal Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Steven A Moore
- Department of Pathology, The University of Iowa, Iowa City, IA, USA
| | - Rizwan Hamid
- Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
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6
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Cassini TA, Duncan L, Rives LC, Newman JH, Phillips JA, Koziura ME, Brault J, Hamid R, Cogan J. Whole genome sequencing reveals novel IGHMBP2 variant leading to unique cryptic splice-site and Charcot-Marie-Tooth phenotype with early onset symptoms. Mol Genet Genomic Med 2019; 7:e00676. [PMID: 31020813 PMCID: PMC6565564 DOI: 10.1002/mgg3.676] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2018] [Revised: 02/24/2019] [Accepted: 03/06/2019] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Rare variants (RV) in immunoglobulin mu-binding protein 2 (IGHMBP2) [OMIM 600502] can cause an autosomal recessive type of Charcot-Marie-Tooth (CMT) disease [OMIM 616155], an inherited peripheral neuropathy. Over 40 different genes are associated with CMT, with different possible inheritance patterns. METHODS AND RESULTS An 11-year-old female with motor delays was found to have distal atrophy, weakness, and areflexia without bulbar or sensory findings. Her clinical evaluation was unrevealing. Whole exome sequencing (WES) revealed a maternally inherited IGHMBP2 RV (c.1730T>C) predicted to be pathogenic, but no variant on the other allele was identified. Deletion and duplication analysis was negative. She was referred to the Undiagnosed Disease Network (UDN) for further evaluation. Whole genome sequencing (WGS) confirmed the previously identified IGHMBP2 RV and identified a paternally inherited non-coding IGHMBP2 RV. This was predicted to activate a cryptic splice site perturbing IGHMBP2 splicing. Reverse transcriptase polymerase chain reaction (RT-PCR) analysis was consistent with activation of the cryptic splice site. The abnormal transcript was shown to undergo nonsense-mediated decay (NMD), resulting in halpoinsufficiency. CONCLUSION This case demonstrates the deficiencies of WES and traditional molecular analyses and highlights the advantages of utilization of WGS and functional studies.
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Affiliation(s)
- Thomas A Cassini
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee.,Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Laura Duncan
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Lynette C Rives
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - John H Newman
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee
| | - John A Phillips
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Mary E Koziura
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Jennifer Brault
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Rizwan Hamid
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Joy Cogan
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
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