1
|
A novel partial duplication in OPHN1, associated with vermis cerebellar hypoplasia, seizures and developmental delay. GENE REPORTS 2022. [DOI: 10.1016/j.genrep.2022.101590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
2
|
Bogliş A, Cosma AS, Tripon F, Bãnescu C. Exon 21 deletion in the OPHN1 gene in a family with syndromic X-linked intellectual disability: Case report. Medicine (Baltimore) 2020; 99:e21632. [PMID: 32872024 PMCID: PMC7437857 DOI: 10.1097/md.0000000000021632] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
INTRODUCTION The oligophrenin-1 (OPHN1) gene, localized on the X chromosome, is a Rho-GTPase activating protein that is related to syndromic X-linked intellectual disability (XLID). XLID, characterized by brain anomalies, namely cerebellar hypoplasia, specific facial features, and intellectual disability, is produced by different mutations in the OPHN1 gene. PATIENT CONCERNS In this report, we present the clinical and molecular findings of a family affected by a mild XLID due to a deletion in the OPHN1 gene, exon 21, Xq12 region using Multiplex Ligation-dependent Probe Amplification (MLPA) analysis. The clinical features present in the family are a mild developmental delay, behavioral disturbances, facial dysmorphism, pes planus, nystagmus, strabismus, epilepsy, and occipital arachnoid cyst. INTERVENTIONS The MLPA analysis was performed for investigation of the copy number variations within the X chromosome for the family. DIAGNOSIS AND OUTCOME The MLPA analysis detected a deletion in the OPHN1 gene, exon 21 for the proband, and a heterozygous deletion for the probands mother. The deletion of the Xq12 region of maternal origin, including the exon 21 of the OPHN1 gene, confirmed for the probands nephew. LESSONS Our findings emphasize the utility of the MLPA analysis to identify deletions in the OPHN1 gene responsible for syndromic XLID. Therefore, we suggest that MLPA analysis should be performed as an alternative diagnostic test for all patients with a mild intellectual disability associated or not with behavioral disturbances, facial dysmorphism, and brain anomalies.
Collapse
Affiliation(s)
- Alina Bogliş
- Laboratory of Medical Genetics, Emergency Clinical County Hospital Târgu Mureş, Târgu Mureş¸ Romania
- Department of Genetics, George Emil Palade University of Medicine, Pharmacy, Sciences, and Technology of Târgu Mureş, Târgu Mureş, Romania
- Laboratory of Molecular Biology/Genetics, Center for Advanced Medical and Pharmaceutical Research, George Emil Palade University of Medicine, Pharmacy, Sciences, and Technology of Târgu Mureş, Târgu Mureş, Romania
| | - Adriana S. Cosma
- Laboratory of Medical Genetics, Emergency Clinical County Hospital Târgu Mureş, Târgu Mureş¸ Romania
| | - Florin Tripon
- Laboratory of Medical Genetics, Emergency Clinical County Hospital Târgu Mureş, Târgu Mureş¸ Romania
- Department of Genetics, George Emil Palade University of Medicine, Pharmacy, Sciences, and Technology of Târgu Mureş, Târgu Mureş, Romania
- Laboratory of Molecular Biology/Genetics, Center for Advanced Medical and Pharmaceutical Research, George Emil Palade University of Medicine, Pharmacy, Sciences, and Technology of Târgu Mureş, Târgu Mureş, Romania
| | - Claudia Bãnescu
- Laboratory of Medical Genetics, Emergency Clinical County Hospital Târgu Mureş, Târgu Mureş¸ Romania
- Department of Genetics, George Emil Palade University of Medicine, Pharmacy, Sciences, and Technology of Târgu Mureş, Târgu Mureş, Romania
- Laboratory of Molecular Biology/Genetics, Center for Advanced Medical and Pharmaceutical Research, George Emil Palade University of Medicine, Pharmacy, Sciences, and Technology of Târgu Mureş, Târgu Mureş, Romania
| |
Collapse
|
3
|
Moortgat S, Lederer D, Deprez M, Buzatu M, Clapuyt P, Boulanger S, Benoit V, Mary S, Guichet A, Ziegler A, Colin E, Bonneau D, Maystadt I. Expanding the phenotypic spectrum associated with OPHN1 mutations: Report of 17 individuals with intellectual disability but no cerebellar hypoplasia. Eur J Med Genet 2018; 61:442-450. [PMID: 29510240 DOI: 10.1016/j.ejmg.2018.03.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Revised: 03/02/2018] [Accepted: 03/02/2018] [Indexed: 01/20/2023]
Abstract
Mutations in the oligophrenin 1 gene (OPHN1) have been identified in patients with X-linked intellectual disability (XLID) associated with cerebellar hypoplasia and ventriculomegaly, suggesting it could be a recognizable syndromic intellectual disability (ID). Affected individuals share additional clinical features including speech delay, seizures, strabismus, behavioral difficulties, and slight facial dysmorphism. OPHN1 is located in Xq12 and encodes a Rho-GTPase-activating protein involved in the regulation of the G-protein cycle. Rho protein members play an important role in dendritic growth and in plasticity of excitatory synapses. Here we report on 17 individuals from four unrelated families affected by mild to severe intellectual disability due to OPHN1 mutations without cerebellar anomaly on brain MRI. We describe clinical, genetic and neuroimaging data of affected patients. Among the identified OPHN1 mutations, we report for the first time a missense mutation occurring in a mosaic state. We discuss the intrafamilial clinical variability of the disease and compare our patients with those previously reported. We emphasize the power of next generation techniques (X-exome sequencing, whole-exome sequencing and targeted multi-gene panel) to expand the phenotypic and mutational spectrum of OPHN1-related ID.
Collapse
Affiliation(s)
- Stéphanie Moortgat
- Centre de Génétique Humaine, Institut de Pathologie et de Génétique, Charleroi, Gosselies, Belgium.
| | - Damien Lederer
- Centre de Génétique Humaine, Institut de Pathologie et de Génétique, Charleroi, Gosselies, Belgium
| | - Marie Deprez
- Centre de Génétique Humaine, Institut de Pathologie et de Génétique, Charleroi, Gosselies, Belgium; Département de Neuro-pédiatrie, Clinique Sainte-Elisabeth, Namur, Belgium
| | - Marga Buzatu
- Département de Neuro-pédiatrie, Hôpital Civil Marie Curie, Charleroi, Belgium
| | - Philippe Clapuyt
- Department of Radiology, Pediatric Imaging Unit, Cliniques Universitaires Saint-Luc, Université Catholique de Louvain, Brussels, Belgium
| | - Sébastien Boulanger
- Centre de Génétique Humaine, Institut de Pathologie et de Génétique, Charleroi, Gosselies, Belgium
| | - Valérie Benoit
- Centre de Génétique Humaine, Institut de Pathologie et de Génétique, Charleroi, Gosselies, Belgium
| | - Sandrine Mary
- Centre de Génétique Humaine, Institut de Pathologie et de Génétique, Charleroi, Gosselies, Belgium
| | - Agnès Guichet
- Department of Biochemistry and Genetics, Angers University Hospital, and UMR INSERM 1083, CNRS 6015, Angers, France
| | - Alban Ziegler
- Department of Biochemistry and Genetics, Angers University Hospital, and UMR INSERM 1083, CNRS 6015, Angers, France
| | - Estelle Colin
- Department of Biochemistry and Genetics, Angers University Hospital, and UMR INSERM 1083, CNRS 6015, Angers, France
| | - Dominique Bonneau
- Department of Biochemistry and Genetics, Angers University Hospital, and UMR INSERM 1083, CNRS 6015, Angers, France
| | - Isabelle Maystadt
- Centre de Génétique Humaine, Institut de Pathologie et de Génétique, Charleroi, Gosselies, Belgium
| |
Collapse
|
4
|
Abstract
X-linked cerebellar ataxias (XLCA) are an expanding group of genetically heterogeneous and clinically variable conditions characterized by cerebellar dysgenesis (hypoplasia, atrophy, or dysplasia) caused by gene mutations or genomic imbalances on the X chromosome. The neurologic features of XLCA include hypotonia, developmental delay, intellectual disability, ataxia, and other cerebellar signs. Normal cognitive development has also been reported. Cerebellar defects may be isolated or associated with other brain malformations or extraneurologic involvement. More than 20 genes on the X chromosome, mainly encoding for proteins involved in brain development and synaptic function that have been constantly or occasionally associated with a pathologic cerebellar phenotype, and several families with X-linked inheritance have been reported. Given the excess of males with ataxia, this group of conditions is probably underestimated and families of patients with neuroradiologic and clinical evidence of a cerebellar disorder should be counseled for high risk of X-linked inheritance.
Collapse
Affiliation(s)
- Ginevra Zanni
- Unit of Neuromuscular and Neurodegenerative Disorders, Bambino Gesu' Children's Research Hospital, Rome, Italy.
| | - Enrico Bertini
- Unit of Neuromuscular and Neurodegenerative Disorders, Bambino Gesu' Children's Research Hospital, Rome, Italy
| |
Collapse
|
5
|
Large in-frame intragenic deletion of OPHN1 in a male patient with a normal intelligence quotient score. Clin Dysmorphol 2017; 26:47-49. [PMID: 27390894 DOI: 10.1097/mcd.0000000000000139] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
|
6
|
Vásquez-Velásquez AI, Rivera H, Castro AG, Jaloma-Cruz AR, Juárez CI, Lara-Navarro IJ, Córdova-Fletes C, Mendoza-Pérez P, García-Ortiz JE. Two girls with a de novo Xq rearrangement of paternal origin: t(X;9)(q24;q12) or rea(X)dup q. Taiwan J Obstet Gynecol 2016; 55:275-80. [PMID: 27125414 DOI: 10.1016/j.tjog.2015.09.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/17/2015] [Indexed: 11/18/2022] Open
Abstract
OBJECTIVE We report on two rare Xq rearrangements, namely a t(X;9)(q24;q12) found in a mildly-affected girl (Patient 1) and a rea(X)dup q concomitant with a rob(14;21)mat in a Down syndrome girl (Patient 2). CASE REPORT Both rearrangements were characterized by banding techniques [Giemsa (G), constitutive heterochromatin (C), and bromodeoxyuridine (BrdU) pulse], fluorescence in situ hybridization (FISH) assays, human androgen receptor (HUMAR) assays, and microarray analyses. Patient 1 had a t(X;9)(q24;q12)dn. Patient 2 had a de novo rea(X)(qter→q23 or q24::p11.2→qter) concomitant with an unbalanced rob(14;21)mat. X-Inactivation studies in metaphases and DNA revealed a fully skewed inactivation: the normal homolog was silenced in Patient 1 and the rea(X) in Patient 2. Both rearranged X chromosomes were of paternal descent. Microarray analyses revealed no imbalances in Patient 1 whereas loss of Xp (∼52 Mb) and duplication of Xq (∼44 Mb) and 21q were confirmed in Patient 2. CONCLUSION Our observations further document the cytogenetic heterogeneity and predominant paternal origin of certain de novo X-chromosome rearrangements.
Collapse
Affiliation(s)
- Ana I Vásquez-Velásquez
- División de Genética, Centro de Investigación Biomédica de Occidente, Centro Médico Nacional de Occidente, Instituto Mexicano del Seguro Social, Guadalajara, Mexico
| | - Horacio Rivera
- División de Genética, Centro de Investigación Biomédica de Occidente, Centro Médico Nacional de Occidente, Instituto Mexicano del Seguro Social, Guadalajara, Mexico; Departamento de Biología Molecular y Genómica, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Mexico
| | - Ana G Castro
- División de Medicina Molecular, Centro de Investigación Biomédica de Occidente, Centro Médico Nacional de Occidente, Instituto Mexicano del Seguro Social, Guadalajara, Mexico; Doctorado en Genética Humana, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Mexico
| | - Ana R Jaloma-Cruz
- División de Genética, Centro de Investigación Biomédica de Occidente, Centro Médico Nacional de Occidente, Instituto Mexicano del Seguro Social, Guadalajara, Mexico
| | - Clara I Juárez
- División de Medicina Molecular, Centro de Investigación Biomédica de Occidente, Centro Médico Nacional de Occidente, Instituto Mexicano del Seguro Social, Guadalajara, Mexico; Doctorado en Genética Humana, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Mexico
| | - Irving J Lara-Navarro
- Facultad de Biología, Centro Universitario de Ciencias Biológicas y Agropecuarias, Universidad de Guadalajara, Guadalajara, Mexico
| | - Carlos Córdova-Fletes
- Laboratorio de Citogenómica y Microarreglos, Departamento de Bioquímica y Medicina Molecular, Facultad de Medicina, Universidad Autónoma de Nuevo León, Monterrey, Mexico
| | - Paul Mendoza-Pérez
- Laboratorio de Citogenómica y Microarreglos, Departamento de Bioquímica y Medicina Molecular, Facultad de Medicina, Universidad Autónoma de Nuevo León, Monterrey, Mexico
| | - José E García-Ortiz
- División de Genética, Centro de Investigación Biomédica de Occidente, Centro Médico Nacional de Occidente, Instituto Mexicano del Seguro Social, Guadalajara, Mexico.
| |
Collapse
|
7
|
A novel in-frame deletion affecting the BAR domain of OPHN1 in a family with intellectual disability and hippocampal alterations. Eur J Hum Genet 2013; 22:644-51. [PMID: 24105372 DOI: 10.1038/ejhg.2013.216] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Revised: 08/12/2013] [Accepted: 08/16/2013] [Indexed: 12/13/2022] Open
Abstract
Oligophrenin-1 (OPHN1) is one of at least seven genes located on chromosome X that take part in Rho GTPase-dependent signaling pathways involved in X-linked intellectual disability (XLID). Mutations in OPHN1 were primarily described as an exclusive cause of non-syndromic XLID, but the re-evaluation of the affected individuals using brain imaging displayed fronto-temporal atrophy and cerebellar hypoplasia as neuroanatomical marks. In this study, we describe clinical, genetic and neuroimaging data of a three generation Brazilian XLID family co-segregating a novel intragenic deletion in OPHN1. This deletion results in an in-frame loss of exon 7 at transcription level (c.781_891del; r.487_597del), which is predicted to abolish 37 amino acids from the highly conserved N-terminal BAR domain of OPHN1. cDNA expression analysis demonstrated that the mutant OPHN1 transcript is stable and no abnormal splicing was observed. Features shared by the affected males of this family include neonatal hypotonia, strabismus, prominent root of the nose, deep set eyes, hyperactivity and instability/intolerance to frustration. Cranial MRI scans showed large lateral ventricles, vermis hypoplasia and cystic dilatation of the cisterna magna in all affected males. Interestingly, hippocampal alterations that have not been reported in patients with loss-of-function OPHN1 mutations were found in three affected individuals, suggesting an important function for the BAR domain in the hippocampus. This is the first description of an in-frame deletion within the BAR domain of OPHN1 and could provide new insights into the role of this domain in relation to brain and cognitive development or function.
Collapse
|
8
|
Sel S, Kaiser M, Nass N, Trau S, Roepke A, Storsberg J, Hampel U, Paulsen F, Kalinski T. Oligophrenin-1 (Ophn1) is expressed in mouse retinal vessels. Gene Expr Patterns 2012; 12:63-7. [DOI: 10.1016/j.gep.2011.11.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2011] [Revised: 10/18/2011] [Accepted: 11/07/2011] [Indexed: 12/20/2022]
|
9
|
Pirozzi F, Di Raimo FR, Zanni G, Bertini E, Billuart P, Tartaglione T, Tabolacci E, Brancaccio A, Neri G, Chiurazzi P. Insertion of 16 amino acids in the BAR domain of the oligophrenin 1 protein causes mental retardation and cerebellar hypoplasia in an Italian family. Hum Mutat 2011; 32:E2294-307. [PMID: 21796728 DOI: 10.1002/humu.21567] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2010] [Accepted: 07/07/2011] [Indexed: 11/10/2022]
Abstract
We observed a three-generation family with two maternal cousins and an uncle affected by mental retardation (MR) with cerebellar hypoplasia. X-linked inheritance and the presence of cerebellar malformation suggested a mutation in the OPHN1 gene. In fact, mutational screening revealed a 2-bp deletion that abolishes a donor splicing site, resulting in the inclusion of the initial 48 nucleotides of intron 7 in the mRNA. This mutation determines the production of a mutant oligophrenin 1 protein with 16 extra amino acids inserted in-frame in the N-terminal BAR (Bin1/amphiphysin/Rvs167) domain. This is the first case of a mutation in OPHN1 that does not result in the production of a truncated protein or in its complete loss. OPHN1 (ARHGAP41) encodes a GTPase-activating (GAP) protein belonging to the GRAF subfamily characterized by an N-terminal BAR domain, followed by a pleckstrin-homology (PH) domain and the GAP domain. GRAF proteins play a role in endocytosis and are supposed to dimerize via their BAR domain, that induces membrane curvature. The extra 16 amino acids cause the insertion of 4.4 turns in the third alpha-helix of the BAR domain and apparently impair the protein function. In fact, the clinical phenotype of these patients is identical to that of patients with loss-of-function mutations.
Collapse
|
10
|
Clinical and molecular characterization of a transmitted reciprocal translocation t(1;12)(p32.1;q21.3) in a family co-segregating with mental retardation, language delay, and microcephaly. BMC MEDICAL GENETICS 2011; 12:70. [PMID: 21595979 PMCID: PMC3125236 DOI: 10.1186/1471-2350-12-70] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/09/2010] [Accepted: 05/20/2011] [Indexed: 01/08/2023]
Abstract
BACKGROUND Chromosome translocation associated with neurodevelopmental disorders provides an opportunity to identify new disease-associated genes and gain new insight into their function. During chromosome analysis, we identified a reciprocal translocation between chromosomes 1p and 12q, t(1; 12)(p32.1; q21.3), co-segregating with microcephaly, language delay, and severe psychomotor retardation in a mother and her two affected boys. METHODS Fluorescence in situ hybridization (FISH), long-range PCR, and direct sequencing were used to map the breakpoints on chromosomes 1p and 12q. A reporter gene assay was conducted in human neuroblastoma (SKNSH) and Chinese hamster ovary (CHO) cell lines to assess the functional implication of the fusion sequences between chromosomes 12 and 1. RESULTS We determined both breakpoints at the nucleotide level. Neither breakpoint disrupted any known gene directly. The breakpoint on chromosome 1p was located amid a gene-poor region of ~ 1.1 Mb, while the breakpoint on chromosome 12q was located ~ 3.4 kb downstream of the ALX1 gene, a homeobox gene. In the reporter gene assay, we discovered that the fusion sequences construct between chromosomes 12 and 1 had a ~ 1.5 to 2-fold increased reporter gene activity compared with the corresponding normal chromosome 12 sequences construct. CONCLUSION Our findings imply that the translocation may enhance the expression of the ALX1 gene via the position effect and result in the clinical symptoms of this family. Our findings may also expand the clinical phenotype spectrum of ALX1-related human diseases as loss of the ALX1 function was recently reported to result in abnormal craniofacial development.
Collapse
|
11
|
Zanni G, Bertini ES. X-linked disorders with cerebellar dysgenesis. Orphanet J Rare Dis 2011; 6:24. [PMID: 21569638 PMCID: PMC3115841 DOI: 10.1186/1750-1172-6-24] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2010] [Accepted: 05/15/2011] [Indexed: 12/15/2022] Open
Abstract
X-linked disorders with cerebellar dysgenesis (XLCD) are a genetically heterogeneous and clinically variable group of disorders in which the hallmark is a cerebellar defect (hypoplasia, atrophy or dysplasia) visible on brain imaging, caused by gene mutations or genomic imbalances on the X-chromosome. The neurological features of XLCD include hypotonia, developmental delay, intellectual disability, ataxia and/or other cerebellar signs. Normal cognitive development has also been reported. Cerebellar dysgenesis may be isolated or associated with other brain malformations or multiorgan involvement. There are at least 15 genes on the X-chromosome that have been constantly or occasionally associated with a pathological cerebellar phenotype. 8 XLCD loci have been mapped and several families with X-linked inheritance have been reported. Recently, two recurrent duplication syndromes in Xq28 have been associated with cerebellar hypoplasia. Given the report of several forms of XLCD and the excess of males with ataxia, this group of conditions is probably underestimated and families of patients with neuroradiological and clinical evidence of a cerebellar disorder should be counseled for high risk of X-linked inheritance.
Collapse
Affiliation(s)
- Ginevra Zanni
- Unit of Molecular Medicine, Departement of Neurosciences, Bambino Gesù ediatric Research Hospital, 4 Piazza S. Onofrio, 00165 Rome, Italy.
| | | |
Collapse
|
12
|
Al-Owain M, Kaya N, Al-Zaidan H, Al-Hashmi N, Al-Bakheet A, Al-Muhaizea M, Chedrawi A, Basran RK, Milunsky A. Novel intragenic deletion in OPHN1 in a family causing XLMR with cerebellar hypoplasia and distinctive facial appearance. Clin Genet 2011; 79:363-70. [DOI: 10.1111/j.1399-0004.2010.01462.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|