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Kharrat M, Triki C, Ben Isaa A, Bouchaala W, Alila O, Chouchen J, Ghouliya Y, Kamoun F, Tlili A, Fakhfakh F. Expanding the genetic and phenotypic spectrum of TRAPPC9 and MID2-related neurodevelopmental disabilities: report of two novel mutations, 3D-modelling, and molecular docking studies. J Hum Genet 2024; 69:291-299. [PMID: 38467738 DOI: 10.1038/s10038-024-01242-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 02/27/2024] [Accepted: 02/28/2024] [Indexed: 03/13/2024]
Abstract
Intellectual disabilities (ID) and autism spectrum disorders (ASD) have a variety of etiologies, including environmental and genetic factors. Our study reports a psychiatric clinical investigation and a molecular analysis using whole exome sequencing (WES) of two siblings with ID and ASD from a consanguineous family. Bioinformatic prediction and molecular docking analysis were also carried out. The two patients were diagnosed with profound intellectual disability, brain malformations such as cortical atrophy, acquired microcephaly, and autism level III. The neurological and neuropsychiatric examination revealed that P2 was more severely affected than P1, as he was unable to walk, presented with dysmorphic feature and exhibited self and hetero aggressive behaviors. The molecular investigations revealed a novel TRAPPC9 biallelic nonsense mutation (c.2920 C > T, p.R974X) in the two siblings. The more severely affected patient (P2) presented, along with the TRAPPC9 variant, a new missense mutation c.166 C > T (p.R56C) in the MID2 gene at hemizygous state, while his sister P1 was merely a carrier. The 3D modelling and molecular docking analysis revealed that c.166 C > T variant could affect the ability of MID2 binding to Astrin, leading to dysregulation of microtubule dynamics and causing morphological abnormalities in the brain. As our knowledge, the MID2 mutation (p.R56C) is the first one to be detected in Tunisia and causing phenotypic variability between the siblings. We extend the genetic and clinical spectrum of TRAPPC9 and MID2 mutations and highlights the possible concomitant presence of X-linked as well as autosomal recessive inheritance to causing ID, microcephaly, and autism.
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Affiliation(s)
- Marwa Kharrat
- Laboratory of Molecular and Functional Genetics, Faculty of Sciences of Sfax University, Sfax, Tunisia.
| | - Chahnez Triki
- Child Neurology Department, Hedi Chaker Hospital, Sfax, Tunisia
- Research laboratory (LR19ES15), Sfax Medical School, Sfax University, Sfax, Tunisia
| | - Abir Ben Isaa
- Child Neurology Department, Hedi Chaker Hospital, Sfax, Tunisia
- Research laboratory (LR19ES15), Sfax Medical School, Sfax University, Sfax, Tunisia
| | - Wafa Bouchaala
- Child Neurology Department, Hedi Chaker Hospital, Sfax, Tunisia
- Research laboratory (LR19ES15), Sfax Medical School, Sfax University, Sfax, Tunisia
| | - Olfa Alila
- Laboratory of Molecular and Functional Genetics, Faculty of Sciences of Sfax University, Sfax, Tunisia
| | - Jihen Chouchen
- Department of Applied Biology, College of Sciences, University of Sharjah, Sharjah, United Arab Emirates
| | - Yosra Ghouliya
- Child Neurology Department, Hedi Chaker Hospital, Sfax, Tunisia
- Research laboratory (LR19ES15), Sfax Medical School, Sfax University, Sfax, Tunisia
| | - Fatma Kamoun
- Child Neurology Department, Hedi Chaker Hospital, Sfax, Tunisia
- Research laboratory (LR19ES15), Sfax Medical School, Sfax University, Sfax, Tunisia
| | - Abdelaziz Tlili
- Department of Applied Biology, College of Sciences, University of Sharjah, Sharjah, United Arab Emirates
| | - Faiza Fakhfakh
- Laboratory of Molecular and Functional Genetics, Faculty of Sciences of Sfax University, Sfax, Tunisia.
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Uctepe E, Yesilyurt A, Esen FN, Tumer S, Mancilar H, Sonmez FM. TRAPPC9-Related Intellectual Disability: Report of Two New Cases and Review of the Literature. Mol Syndromol 2023; 14:485-492. [PMID: 38058760 PMCID: PMC10697769 DOI: 10.1159/000531439] [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: 03/18/2023] [Accepted: 06/05/2023] [Indexed: 12/08/2023] Open
Abstract
Introduction Hereditary forms of intellectual disability (ID), an estimated prevalence ranging between 1% and 3% in the general population, are among the most important problems in health care. Especially, autosomal-recessive ID has a very heterogeneous molecular basis and a lack of specific phenotypic features. Methods Here, we report on two unrelated patients with autosomal-recessive ID, microcephaly, and autistic features and review the patients with TRAPPC9-related ID. Whole-exome sequencing and array CGH were performed for molecular diagnosis of the patients. Results The first case has a microdeletion on chromosome 8q24.23-q24.3 region which is 1.7 Mb in length and includes the last 5 exons of TRAPPC9, and c.3435delG [p.Thr1146Profs*8] deletion. The second case has a homozygous missense c.623A>C (p.His208Pro) variant in TRAPPC9 which is detected by means of whole-exome sequencing study of the proband. We also reviewed the clinical findings and mutation spectrum of all patients with TRAPPC9-related ID reported so far. Conclusions Our study showed that the most consistent clinical findings for TRAPPC9-related ID are ID, microcephaly, and some structural brain MRI abnormalities. The mutations in the TRAPPC9 are scattered throughout all exons of TRAPPC9 indicating there is no hot spot mutation region in this gene.
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Affiliation(s)
- Eyyup Uctepe
- Acibadem Ankara Tissue Typing Laboratory, Ankara, Turkey
| | - Ahmet Yesilyurt
- Acibadem Labgen Genetic Diagnosis Center, Istanbul, Turkey
- Acibadem Maslak Hospital, Istanbul, Turkey
| | | | - Sait Tumer
- Acibadem Labgen Genetic Diagnosis Center, Istanbul, Turkey
| | | | - Fatma Mujgan Sonmez
- Karadeniz Technical University Faculty of Medicine, Department of Child Neurology, Ankara, Turkey
- Private office, Child Neurology, Ankara, Turkey
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Penon-Portmann M, Hodoglugil U, Arun P W, Yip T, Slavotinek A, Tenney JL. TRAPPC9-related neurodevelopmental disorder: Report of a homozygous deletion in TRAPPC9 due to paternal uniparental isodisomy. Am J Med Genet A 2023; 191:1077-1082. [PMID: 36574751 DOI: 10.1002/ajmg.a.63100] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2022] [Revised: 10/24/2022] [Accepted: 12/11/2022] [Indexed: 12/28/2022]
Abstract
TRAPPC9 loss-of-function biallelic variants are associated with an autosomal recessive intellectual disability syndrome (Online Mendelian Inheritance of Man no. 613192), also characterized by microcephaly, hypertelorism, obesity, growth delay, and behavioral differences. Here, we describe an 8-year-old Hispanic female with neurodevelopmental disorder, partial epilepsy, microcephaly, bilateral cleft lip and alveolus, growth delay, and dysmorphic features. She had abnormal myelination, mega cisterna magna, and colpocephaly on brain magnetic resonance imaging (MRI). Microarray showed a single ~146 Mb region of homozygosity (ROH) encompassing all of Chromosome 8, consistent with uniparental isodisomy (UPD). Exome sequencing performed in-house did not identify single nucleotide variants to explain her phenotype. Algorithms developed in-house and further evaluation of BAM files revealed a homozygous deletion overlapping Exon 2 in TRAPPC9 within the ROH. Subsequent del/dup analyses with exon-level oligo array confirmed a likely pathogenic deletion in TRAPPC9 (NM_031466.5): arr[GRCh37] 8q24.3(141460661_141461780)x0. Our case highlights the implications of downstream analyses from UPD/ROH given the increased risk for AR conditions, the strengths of combining orthologous molecular methods to establish a diagnosis and further delineates the TRAPPC9-related phenotype in an individual of Hispanic ancestry.
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Affiliation(s)
- Monica Penon-Portmann
- Division of Medical Genetics, Department of Pediatrics, University of California San Francisco, San Francisco, California, USA.,Division of Genetic Medicine, Department of Pediatrics, University of Washington, Seattle, Washington, USA
| | - Ugur Hodoglugil
- Genomic Medicine Laboratory, University of California San Francisco, San Francisco, California, USA
| | - Wiita Arun P
- Department of Laboratory Medicine, University of California San Francisco, San Francisco, California, USA
| | - Tiffany Yip
- Institute for Human Genetics, 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.,Division of Human Genetics, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Jessica L Tenney
- Division of Medical Genetics, Department of Pediatrics, University of California San Francisco, San Francisco, California, USA
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Amin M, Vignal C, Eltaraifee E, Mohammed IN, Hamed AAA, Elseed MA, Babai A, Elbadi I, Mustafa D, Abubaker R, Mustafa M, Drunat S, Elsayed LEO, Ahmed AE, Boespflug-Tanguy O, Dorboz I. A novel homozygous mutation in TRAPPC9 gene causing autosomal recessive non-syndromic intellectual disability. BMC Med Genomics 2022; 15:236. [PMID: 36348459 PMCID: PMC9644490 DOI: 10.1186/s12920-022-01354-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 09/09/2022] [Indexed: 11/10/2022] Open
Abstract
Background The etiology of intellectual disabilities is diverse and includes both genetic and environmental factors. The genetic causes of intellectual disabilities range from chromosomal aberrations to single gene disorders. The TRAPPC9 gene has been reported to cause autosomal recessive forms of intellectual disabilities in 56 patients from consanguineous and non-consanguineous families around the world. Methods We analyzed two siblings with intellectual disability, microcephaly and delayed motor and speech development from a consanguineous Sudanese family. Genomic DNA was screened for mutations using NGS panel (NextSeq500 Illumina) testing 173 microcephaly associated genes in the Molecular Genetics service in Robert Debre hospital in Paris, France. Results A novel homozygous mutation (NM_031466.7 (TRAPPC9):c.2288dup, p. (Val764Glyfs*7) in exon 14 of TRAPPC9 gene was found in the two patients. The mutation was predicted to cause nonsense mediated decay (NSMD) using SIFT prediction tool. The variant has not been found in either gnomAD or Exac databases. Both parents were heterozygous (carriers) to the mutation. Conclusion This is the first study to report patients with TRAPPC9-related disorder from Sub-Saharan Africa.
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Biallelic loss of TRAPPC9 function links vesicle trafficking pathway to autosomal recessive intellectual disability. J Hum Genet 2022; 67:279-284. [PMID: 34983975 DOI: 10.1038/s10038-021-01007-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Revised: 12/11/2021] [Accepted: 12/13/2021] [Indexed: 11/08/2022]
Abstract
BACKGROUND The trafficking protein particle (TRAPP) complex subunit 9 (C9) protein is a member of TRAPP-II complexes and regulates vesicle trafficking. Biallelic mutations in the TRAPPC9 gene are responsible for intellectual disability with expanded developmental delay, epilepsy, microcephaly, and brain atrophy. TRAPPC9-related disease list is still expanding, however, the functional effects of only a limited fraction of these have been studied. METHODS In a patient with a pathological variant in TRAPPC9, clinical examination and cranial imaging findings were evaluated. Whole-exome sequencing, followed by Sanger sequencing was performed to detect and verify the variant. To confirm the functional effect of the mutation; variant mRNA and protein expression levels were evaluated by qRT-PCR and Western blotting. Immunostaining for TRAPPC9 and lipid droplet accumulation were examined. RESULTS We have identified a novel homozygous c.696C>G (p.Phe232Leu) pathogenic variant in TRAPPC9 (NM_031466.6) gene as a cause of severe developmental delay. Functional characterization of the TRAPPC9 variant resulted in decreased mRNA and protein expression. The intracellular findings showed that TRAPPC9 protein build-up around the nucleus in mutant type while there was no specific accumulation in the control cell line. This disrupted protein pattern affected the amount of neutral lipid-carrying vesicles and their homogenous distribution at a decreasing level. CONCLUSION Biallelic variants in the TRAPPC9 gene have been reported as the underlying cause of intellectual disability. This study provides functional evidence of the novel variant in TRAPPC9 We demonstrated that the loss of function variant exclusively targeting TRAPPC9 may explicate the neurological findings through vesicle trafficking.
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Krämer J, Beer M, Bode H, Winter B. Two Novel Compound Heterozygous Mutations in the TRAPPC9 Gene Reveal a Connection of Non-syndromic Intellectual Disability and Autism Spectrum Disorder. Front Genet 2021; 11:972. [PMID: 33719327 PMCID: PMC7947907 DOI: 10.3389/fgene.2020.00972] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Accepted: 07/31/2020] [Indexed: 12/28/2022] Open
Abstract
Introduction Autism spectrum disorder (ASD) is characterized by deficits in communication, social interaction, and repetitive behavior. Up to 70% of ASD cases are linked with intellectual disability (ID). The major genetic causes for ASD and ID are largely unknown, however, a shared genetic etiology between ASD and ID must be assumed. The trafficking protein particle complex subunit 9 (TRAPPC9) is highly expressed in postmitotic neurons of the cerebral cortex, playing a key role in development. Among 43 reported cases with mutations in TRAPPC9, all (100%) showed ID and developmental delay. Among the cases including information about ASD, 26% were affected (19 cases with information, among them 5 with ASD). Nevertheless, in some cases not classified as ASD, descriptions of autistic features like hand-flapping movements were present. Clinical Findings The affected individual presented with delay of speech development. Physical development was normal. Besides lateral slope of the eye-lid axis no facial abnormalities were evident. The individual was diagnosed with ID and ASD by structured testing. Cerebral MRI revealed associated abnormalities. Genetical Findings The chromosome set was 46,XY without structural changes. Array-CGH showed a normal molecular karyotype (arr(1-22)x2,(X,Y)x1). PCR for the FMR1 gene showed 41 ± 1 CGG repeats, and therefore no evidence of fragile X syndrome. A panel diagnostic for syndromal ID (CASK, EP300, HIVEP2, KIF1A, TRAPPC9) revealed two structural changes in TRAPPC9 in the compound heterozygosity. The mutations c.1678C > T (p.Arg560Cys) and c.3370C > T (p.Pro1124Ser) are classified as missense mutations and are both not described in the literature. Conclusion We report two new missense mutations in the TRAPPC9 gene in one individual with ID and ASD. The TRAPPC9 gene should be part of the diagnostic assessment in ID. ASD must be considered as a feature of TRAPPC9-associated ID. It might have been neglected in the literature and should result in specific testing for ASD in affected individuals.
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Affiliation(s)
- Johannes Krämer
- Division of Pediatric Neurology and Inborn Errors of Metabolism, Children's Hospital, Ulm University, Ulm, Germany
| | - Meinrad Beer
- Department of Radiology, Ulm University, Ulm, Germany
| | - Harald Bode
- Division of Pediatric Neurology and Inborn Errors of Metabolism, Children's Hospital, Ulm University, Ulm, Germany
| | - Benedikt Winter
- Division of Pediatric Neurology and Inborn Errors of Metabolism, Children's Hospital, Ulm University, Ulm, Germany
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Yousefipour F, Mozhdehipanah H, Mahjoubi F. Identification of two novel homozygous nonsense mutations in TRAPPC9 in two unrelated consanguineous families with intellectual Disability from Iran. Mol Genet Genomic Med 2021; 9:e1610. [PMID: 33513295 PMCID: PMC8683625 DOI: 10.1002/mgg3.1610] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 12/14/2020] [Accepted: 12/21/2020] [Indexed: 11/12/2022] Open
Abstract
Background Pathogenic mutations in TRAPPC9 are associated with autosomal recessive Intellectual Disability (ID), a major public health issue that affects about 1–3% of children worldwide. Method Clinical evaluation, magnetic resonance imaging, peripheral blood karyotype, Multiplex ligation‐dependent probe amplification (MLPA), array CGH, and whole‐exome sequencing were used to characterize etiology in three patients from two unrelated consanguineous families of Iranian descent with intellectual disability. Results Whole‐exome sequencing showed two novel homozygous nonsense mutations (c.937C>T) in exon 3 and (c.3103C>T) in exon 19 of TRAPPC9 (NM_031466.7) in two unrelated consanguineous families. Conclusion The two novel variants found in TRAPPC9 caused truncated protein and clinical manifestations such as ID, developmental delay, microcephaly, and brain abnormalities in three patients.
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Affiliation(s)
| | - Hossein Mozhdehipanah
- Department of Neurology, Bou Ali Sina Hospital, Qazvin University of Medical Sciences, Qazvin, Iran
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Bodnar B, DeGruttola A, Zhu Y, Lin Y, Zhang Y, Mo X, Hu W. Emerging role of NIK/IKK2-binding protein (NIBP)/trafficking protein particle complex 9 (TRAPPC9) in nervous system diseases. Transl Res 2020; 224:55-70. [PMID: 32434006 PMCID: PMC7442628 DOI: 10.1016/j.trsl.2020.05.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 05/02/2020] [Accepted: 05/05/2020] [Indexed: 02/05/2023]
Abstract
NFκB signaling and protein trafficking network play important roles in various biological and pathological processes. NIK-and-IKK2-binding protein (NIBP), also known as trafficking protein particle complex 9 (TRAPPC9), is a prototype member of a novel protein family, and has been shown to regulate both NFκB signaling pathway and protein transport/trafficking. NIBP is extensively expressed in the nervous system and plays an important role in regulating neurogenesis and neuronal differentiation. NIBP/TRAPPC9 mutations have been linked to an autosomal recessive intellectual disability syndrome, called NIBP Syndrome, which is characterized by nonsyndromic autosomal recessive intellectual disability along with other symptoms such as obesity, microcephaly, and facial dysmorphia. As more cases of NIBP Syndrome are identified, new light is being shed on the role of NIBP/TRAPPC9 in the central nervous system developments and diseases. NIBP is also involved in the enteric nervous system. This review will highlight the importance of NIBP/TRAPPC9 in central and enteric nervous system diseases, and the established possible mechanisms for developing a potential therapeutic.
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Affiliation(s)
- Brittany Bodnar
- Center for Metabolic Disease Research, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania; MD/PhD and Biomedical Sciences Graduate Program, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania
| | - Arianna DeGruttola
- Center for Metabolic Disease Research, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania; MD/PhD and Biomedical Sciences Graduate Program, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania
| | - Yuanjun Zhu
- Center for Metabolic Disease Research, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania; Department of Pathology and Laboratory Medicine, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania; Department of Molecular and Cellular Pharmacology, Peking University School of Pharmaceutical Sciences, Beijing, China
| | - Yuan Lin
- Center for Metabolic Disease Research, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania; Department of Pathology and Laboratory Medicine, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania
| | - Yonggang Zhang
- Center for Stem Cell Research and Application, Institute of Blood Transfusion, Chinese Academy of Medical Sciences & Peking Union Medical College (CAMS & PUMC), Chengdu, China
| | - Xianming Mo
- Laboratory of Stem Cell Biology, State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu, China
| | - Wenhui Hu
- Center for Metabolic Disease Research, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania; MD/PhD and Biomedical Sciences Graduate Program, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania; Department of Pathology and Laboratory Medicine, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania.
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Wilton KM, Gunderson LB, Hasadsri L, Wood CP, Schimmenti LA. Profound intellectual disability caused by homozygous TRAPPC9 pathogenic variant in a man from Malta. Mol Genet Genomic Med 2020; 8:e1211. [PMID: 32162493 PMCID: PMC7216808 DOI: 10.1002/mgg3.1211] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Accepted: 02/24/2020] [Indexed: 01/02/2023] Open
Abstract
Background Intellectual disability is a complex multi‐faceted condition with diverse underlying etiologies. One rare form of intellectual disability is secondary to the loss of TRAPPC9, an activator of NF‐κB and a mediator of intracellular protein processing and trafficking. TRAPPC9 deficiency has been described in 48 patients with more than 15 pathologic variants. Method Clinical evaluation, magnetic resonance imaging, and whole‐exome sequencing were used to characterize the underlying cause of absent speech, restricted/repetitive behaviors, and worsening behavioral outbursts in 27‐year‐old man from Malta. Results Magnetic Resonance Imaging showed morphologic abnormalities, including global cerebral and cerebellar hypoplasia. Genetic analysis through Whole Exome Sequencing identified a homozygous deletion (c.568_574del) in TRAPPC9 resulting in a frameshift, premature stop codon, and ultimately a truncated protein (p.Trp190Argfs*95). In this case, the pathogenic variant was homozygous, identified in both of the parents without known consanguinity. Conclusion Given the phenotype and genotype consistent with a deficiency in TRAPPC9, it is likely that this patient represents a novel case of this rare genetic syndrome. Specifically, this case, in the context of 48 total reported patients, raises questions as to the geographic origin of the pathologic variant and optimal detection and therapeutic intervention for this condition.
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Affiliation(s)
- Katelynn M Wilton
- Mayo Clinic Alix School of Medicine Medical Scientist Training Program, Mayo Clinic, Rochester, MN, USA
| | | | - Linda Hasadsri
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | | | - Lisa A Schimmenti
- Department of Clinical Genomics, Mayo Clinic, Rochester, MN, USA.,Department of Otorhinolaryngology, Mayo Clinic, Rochester, MN, USA
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The clinical benefit of array-based comparative genomic hybridization for detection of copy number variants in Czech children with intellectual disability and developmental delay. BMC Med Genomics 2019; 12:111. [PMID: 31337399 PMCID: PMC6651926 DOI: 10.1186/s12920-019-0559-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 07/16/2019] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND Chromosomal microarray analysis has been shown to be a valuable and cost effective assay for elucidating copy number variants (CNVs) in children with intellectual disability and developmental delay (ID/DD). METHODS In our study, we performed array-based comparative genomic hybridization (array-CGH) analysis using oligonucleotide-based platforms in 542 Czech patients with ID/DD, autism spectrum disorders and multiple congenital abnormalities. Prior to the array-CGH analysis, all the patients were first examined karyotypically using G-banding. The presence of CNVs and their putative derivation was confirmed using fluorescence in situ hybridization (FISH), multiplex ligation-dependent probe amplification (MLPA) and predominantly relative quantitative polymerase chain reaction (qPCR). RESULTS In total, 5.9% (32/542) patients were positive for karyotypic abnormalities. Pathogenic/likely pathogenic CNVs were identified in 17.7% of them (96/542), variants of uncertain significance (VOUS) were detected in 4.8% (26/542) and likely benign CNVs in 9.2% of cases (50/542). We identified 6.6% (36/542) patients with known recurrent microdeletion (24 cases) and microduplication (12 cases) syndromes, as well as 4.8% (26/542) patients with non-recurrent rare microdeletions (21 cases) and microduplications (5 cases). In the group of patients with submicroscopic pathogenic/likely pathogenic CNVs (13.3%; 68/510) we identified 91.2% (62/68) patients with one CNV, 5.9% (4/68) patients with two likely independent CNVs and 2.9% (2/68) patients with two CNVs resulting from cryptic unbalanced translocations. Of all detected CNVs, 21% (31/147) had a de novo origin, 51% (75/147) were inherited and 28% (41/147) of unknown origin. In our cohort pathogenic/likely pathogenic microdeletions were more frequent than microduplications (69%; 51/74 vs. 31%; 23/74) ranging in size from 0.395 Mb to 10.676 Mb (microdeletions) and 0.544 Mb to 8.156 Mb (microduplications), but their sizes were not significantly different (P = 0.83). The pathogenic/likely pathogenic CNVs (median 2.663 Mb) were significantly larger than benign CNVs (median 0.394 Mb) (P < 0.00001) and likewise the pathogenic/likely pathogenic CNVs (median 2.663 Mb) were significantly larger in size than VOUS (median 0.469 Mb) (P < 0.00001). CONCLUSIONS Our results confirm the benefit of array-CGH in the current clinical genetic diagnostics leading to identification of the genetic cause of ID/DD in affected children.
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Challenges in the clinical interpretation of small de novo copy number variants in neurodevelopmental disorders. Gene 2019; 706:162-171. [PMID: 31085274 DOI: 10.1016/j.gene.2019.05.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 03/27/2019] [Accepted: 05/03/2019] [Indexed: 12/17/2022]
Abstract
In clinical genetics, the need to discriminate between benign and pathogenic variants identified in patients with neurodevelopmental disorders is an absolute necessity. Copy number variants (CNVs) of small size can enable the identification of genes that are critical for neurologic development. However, assigning a definite association with a specific disorder is a difficult task. Among 328 trios analyzed over seven years of activity in a single laboratory, we identified 19 unrelated patients (5.8%) who carried a small (<500 kb) de novo CNV. Four patients had an additional independent de novo CNV. Nine had a variant that could be assigned as definitely pathogenic, whereas the remaining CNVs were considered as variants of unknown significance (VUS). We report clinical and molecular findings of patients harboring VUS. We reviewed the medical literature available for genes impacted by CNVs, obtained the probability of truncating loss-of-function intolerance, and compared overlapping CNVs reported in databases. The classification of small non-recurrent CNVs remains difficult but, among our findings, we provide support for a role of SND1 in the susceptibility of autism, describe a new case of the rare 17p13.1 microduplication syndrome, and report an X-linked duplication involving KIF4A and DLG3 as a likely cause of epilepsy.
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Scuderi C, Saccuzzo L, Vinci M, Castiglia L, Galesi O, Salemi M, Mattina T, Borgione E, Città S, Romano C, Fichera M. Biallelic intragenic duplication in ADGRB3 (BAI3) gene associated with intellectual disability, cerebellar atrophy, and behavioral disorder. Eur J Hum Genet 2019; 27:594-602. [PMID: 30659260 PMCID: PMC6460634 DOI: 10.1038/s41431-018-0321-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Revised: 11/15/2018] [Accepted: 12/04/2018] [Indexed: 11/09/2022] Open
Abstract
In recent years, chromosomal microarray analysis has permitted the discovery of rearrangements underlying several neurodevelopmental disorders and still represents the first diagnostic test for unexplained neurodevelopmental disabilities. Here we report a family of consanguineous parents showing psychiatric disorders and their two sons both affected by intellectual disability, ataxia, and behavioral disorder. SNP/CGH array analysis in this family demonstrated in both siblings a biallelic duplication inherited from the heterozygous parents, disrupting the ADGRB3 gene. ADGRB3, also known as BAI3, belongs to the subfamily of adhesion G protein-coupled receptors (adhesion GPCRs) that regulate many aspects of the central nervous system, including axon guidance, myelination, and synapse formation. Single nucleotide polymorphisms and copy number variants involving ADGRB3 have recently been associated with psychiatric disorders. These findings further support this association and also suggest that biallelic variants affecting the function of the ADGRB3 gene may also cause cognitive impairments and ataxia.
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Affiliation(s)
| | - Lucia Saccuzzo
- Department of Biomedical and Biotechnological Sciences, Medical Genetics, University of Catania, Catania, Italy
| | | | | | | | | | - Teresa Mattina
- Department of Biomedical and Biotechnological Sciences, Medical Genetics, University of Catania, Catania, Italy
| | | | | | | | - Marco Fichera
- Oasi Research Institute-IRCCS, Troina, Italy.
- Department of Biomedical and Biotechnological Sciences, Medical Genetics, University of Catania, Catania, Italy.
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Hnoonual A, Graidist P, Kritsaneepaiboon S, Limprasert P. Novel Compound Heterozygous Mutations in the TRAPPC9 Gene in Two Siblings With Autism and Intellectual Disability. Front Genet 2019; 10:61. [PMID: 30853973 PMCID: PMC6396715 DOI: 10.3389/fgene.2019.00061] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 01/24/2019] [Indexed: 12/11/2022] Open
Abstract
Autism spectrum disorder (ASD) is a highly heterogeneous neurodevelopmental disorder with many contributing risk genes and loci. To date, several intellectual disability (ID) susceptibility genes have frequently been identified in ASD. Here, whole exome sequencing was carried out on a proband with ASD and identified compound heterozygous mutations of the TRAPPC9, which plays a role in the neuronal NF-κB signaling pathway. These mutations consisted of a novel frameshift mutation (c.2415_2416insC, p.His806Profs∗9) and a rare splice site mutation (c.3349+1G>A) that were segregated from an unaffected father and unaffected mother, respectively. These two heterozygous mutations were also identified in the patient’s older brother with ID. Quantitative RT-PCR revealed a significant reduction of TRAPPC9 transcript in two siblings. This study first describes compound heterozygous mutations of the TRAPPC9 gene in two siblings with ASD and ID, which is notable as only homozygous mutations or compound heterozygous for copy number variations and rare variant in this gene have been reported to date and associated with autosomal recessive intellectual disability. The two siblings carrying compound heterozygous TRAPPC9 mutations presented with ID, developmental delay, microcephaly and brain abnormalities similarly to the clinical features found in almost cases with homozygous TRAPPC9 mutation in previous studies. Together this study provides evidence that clinical manifestations of TRAPPC9 mutations as seen in our patients with ID and autism may be broader than previous case reports have indicated.
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Affiliation(s)
- Areerat Hnoonual
- Division of Human Genetics, Department of Pathology, Faculty of Medicine, Prince of Songkla University, Songkhla, Thailand
| | - Potchanapond Graidist
- Department of Biomedical Sciences, Faculty of Medicine, Prince of Songkla University, Songkhla, Thailand.,The Excellent Research Laboratory of Cancer Molecular Biology, Prince of Songkla University, Songkhla, Thailand
| | - Supika Kritsaneepaiboon
- Department of Radiology, Faculty of Medicine, Prince of Songkla University, Songkhla, Thailand
| | - Pornprot Limprasert
- Division of Human Genetics, Department of Pathology, Faculty of Medicine, Prince of Songkla University, Songkhla, Thailand.,Faculty of Medicine, King Mongkut's Institute of Technology Ladkrabang, Bangkok, Thailand
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14
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Costain G, Walker S, Argiropoulos B, Baribeau DA, Bassett AS, Boot E, Devriendt K, Kellam B, Marshall CR, Prasad A, Serrano MA, Stavropoulos DJ, Twede H, Vermeesch JR, Vorstman JAS, Scherer SW. Rare copy number variations affecting the synaptic gene DMXL2 in neurodevelopmental disorders. J Neurodev Disord 2019; 11:3. [PMID: 30732576 PMCID: PMC6366120 DOI: 10.1186/s11689-019-9263-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 01/23/2019] [Indexed: 01/07/2023] Open
Abstract
Background Ultra-rare genetic variants, including non-recurrent copy number variations (CNVs) affecting important dosage-sensitive genes, are important contributors to the etiology of neurodevelopmental disorders (NDDs). Pairing family-based whole-genome sequencing (WGS) with detailed phenotype data can enable novel gene associations in NDDs. Methods We performed WGS of six members from a three-generation family, where three individuals each had a spectrum of features suggestive of a NDD. CNVs and sequence-level variants were identified and further investigated in disease and control databases. Results We identified a novel 252-kb deletion at 15q21 that overlaps the synaptic gene DMXL2 and the gene GLDN. The microdeletion segregated in NDD-affected individuals. Additional rare inherited and de novo sequence-level variants were found that may also be involved, including a missense change in GRIK5. Multiple CNVs and loss-of-function sequence variants affecting DMXL2 were discovered in additional unrelated individuals with a range of NDDs. Conclusions Disruption of DMXL2 may predispose to NDDs including autism spectrum disorder. The robust interpretation of private variants requires a multifaceted approach that incorporates multigenerational pedigrees and genome-wide and population-scale data.
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Affiliation(s)
- Gregory Costain
- Division of Clinical and Metabolic Genetics, The Hospital for Sick Children, Toronto, ON, Canada.,Medical Genetics Residency Training Program, University of Toronto, Toronto, ON, Canada
| | - Susan Walker
- The Centre for Applied Genomics, The Hospital for Sick Children, Toronto, ON, Canada.,Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Bob Argiropoulos
- Department of Medical Genetics, University of Calgary Cumming School of Medicine, Calgary, AB, Canada
| | | | - Anne S Bassett
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada.,The Dalglish Family 22q Clinic, Toronto General Hospital, Toronto, ON, Canada
| | - Erik Boot
- The Dalglish Family 22q Clinic, Toronto General Hospital, Toronto, ON, Canada
| | - Koen Devriendt
- Department of Human Genetics, KU Leuven, Leuven, Flanders, Belgium
| | - Barbara Kellam
- The Centre for Applied Genomics, The Hospital for Sick Children, Toronto, ON, Canada
| | - Christian R Marshall
- The Centre for Applied Genomics, The Hospital for Sick Children, Toronto, ON, Canada.,Genome Diagnostics, Department of Paediatric Laboratory Medicine, The Hospital for Sick Children, Toronto, ON, Canada
| | - Aparna Prasad
- Lineagen, Inc, 2677 East Parleys Way, Salt Lake City, UT, 84109, USA
| | - Moises A Serrano
- Lineagen, Inc, 2677 East Parleys Way, Salt Lake City, UT, 84109, USA
| | - D James Stavropoulos
- Genome Diagnostics, Department of Paediatric Laboratory Medicine, The Hospital for Sick Children, Toronto, ON, Canada
| | - Hope Twede
- Lineagen, Inc, 2677 East Parleys Way, Salt Lake City, UT, 84109, USA
| | | | - Jacob A S Vorstman
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada.,Autism Research Unit, The Hospital for Sick Children, Toronto, ON, Canada
| | - Stephen W Scherer
- The Centre for Applied Genomics, The Hospital for Sick Children, Toronto, ON, Canada. .,Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON, Canada. .,Department of Molecular Genetics and McLaughlin Centre, University of Toronto, Toronto, ON, Canada.
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15
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Sacher M, Shahrzad N, Kamel H, Milev MP. TRAPPopathies: An emerging set of disorders linked to variations in the genes encoding transport protein particle (TRAPP)-associated proteins. Traffic 2018; 20:5-26. [PMID: 30152084 DOI: 10.1111/tra.12615] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 08/23/2018] [Accepted: 08/26/2018] [Indexed: 02/06/2023]
Abstract
The movement of proteins between cellular compartments requires the orchestrated actions of many factors including Rab family GTPases, Soluble NSF Attachment protein REceptors (SNAREs) and so-called tethering factors. One such tethering factor is called TRAnsport Protein Particle (TRAPP), and in humans, TRAPP proteins are distributed into two related complexes called TRAPP II and III. Although thought to act as a single unit within the complex, in the past few years it has become evident that some TRAPP proteins function independently of the complex. Consistent with this, variations in the genes encoding these proteins result in a spectrum of human diseases with diverse, but partially overlapping, phenotypes. This contrasts with other tethering factors such as COG, where variations in the genes that encode its subunits all result in an identical phenotype. In this review, we present an up-to-date summary of all the known disease-related variations of genes encoding TRAPP-associated proteins and the disorders linked to these variations which we now call TRAPPopathies.
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Affiliation(s)
- Michael Sacher
- Department of Biology, Concordia University, Montreal, Quebec, Canada.,Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec, Canada
| | - Nassim Shahrzad
- Department of Medicine, University of California, San Francisco, California
| | - Hiba Kamel
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Miroslav P Milev
- Department of Biology, Concordia University, Montreal, Quebec, Canada
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16
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Han JY, Jang JH, Park J, Lee IG. Targeted Next-Generation Sequencing of Korean Patients With Developmental Delay and/or Intellectual Disability. Front Pediatr 2018; 6:391. [PMID: 30631761 PMCID: PMC6315160 DOI: 10.3389/fped.2018.00391] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 11/28/2018] [Indexed: 12/26/2022] Open
Abstract
Background: Differential diagnosis of developmental delay (DD) and/or intellectual disability (ID) is challenging because of the diversity of phenotypic manifestations as DD/ID patients usually have combined congenital malformations, autism-spectrum disorders, and/or seizure disorder. Thus, unbiased genomic approaches are needed to discover genetic alterations leading to DD and/or ID. Objective: The aim of this study was to investigate the clinical usefulness of targeted next-generation sequencing (NGS) to investigate genetic causes in 35 Korean patients with unexplained DD/ID. Methods: Targeted next-generation sequencing (NGS) using the TruSight One Panel was analyzed in 35 patients with unexplained DD/ID. Sanger sequencing was used to confirm candidate variants, and to define genetic inheritance mode of candidate variant as familial segregation testing. Results: Of 35 patients with DD and/or ID, 10 were found to have underlying genetic etiology and carried X-linked recessive inheritance of ZDHHC9 or autosomal dominant inheritance of SMARCB1, CHD8, LAMA5, NSD1, PAX6, CACNA1H, MBD5, FOXP1, or KCNK18 mutations. No autosomal recessive inherited mutation was identified in this study. As a result, the diagnostic yield of DD/ID by targeted NGS was 29% (10/35), mostly involving may be de novo mutation present in the proband only. A total of seven may be de novo mutations, one paternally inherited, and one maternally inherited mutations that had been reported previously to concede the genetic pathogenesis as known DD and/or ID genes were found in nine patients with available inheritance pattern except LAMA5. Mutations in nine causative genes were detected in patients with similar DD/ID phenotypes in the OMIM database, providing support for genetic evidence as the cause of DD and/or ID. Conclusion: Targeted NGS through singleton analysis with phenotype-first approaches was able to explain 10 out of 35 DD/ID cases. However, the excavation of plausible genetic causes may be de novo, and X-linked disease-causative variants in DD/ID-associated genes requires further genetic analysis.
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Affiliation(s)
- Ji Yoon Han
- Department of Pediatrics, College of Medicine, The Catholic University of Korea, Seoul, South Korea
| | - Ja Hyun Jang
- Department of Laboratory Medicine, Green Cross Genome, Yongin, South Korea
| | - Joonhong Park
- Department of Laboratory Medicine, College of Medicine, The Catholic University of Korea, Seoul, South Korea
| | - In Goo Lee
- Department of Pediatrics, College of Medicine, The Catholic University of Korea, Seoul, South Korea
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17
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Cost Effectiveness of Karyotyping, Chromosomal Microarray Analysis, and Targeted Next-Generation Sequencing of Patients with Unexplained Global Developmental Delay or Intellectual Disability. Mol Diagn Ther 2017; 22:129-138. [DOI: 10.1007/s40291-017-0309-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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18
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Abbasi AA, Blaesius K, Hu H, Latif Z, Picker-Minh S, Khan MN, Farooq S, Khan MA, Kaindl AM. Identification of a novel homozygous TRAPPC9 gene mutation causing non-syndromic intellectual disability, speech disorder, and secondary microcephaly. Am J Med Genet B Neuropsychiatr Genet 2017; 174:839-845. [PMID: 29031008 DOI: 10.1002/ajmg.b.32602] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 08/24/2017] [Accepted: 09/11/2017] [Indexed: 11/11/2022]
Abstract
TRAPPC9 gene mutations have been linked recently to autosomal recessive mental retardation 13 (MRT13; MIM#613192) with only eight families reported world-wide. We assessed patients from two consanguineous pedigrees of Pakistani descent with non-syndromic intellectual disability and postnatal microcephaly through whole exome sequencing (WES) and cosegregation analysis. Here we report six further patients from two pedigrees with homozygous TRAPPC9 gene mutations, the novel nonsense mutation c.2065G>T (p.E689*) and the previously identified nonsense mutation c.1423C>T (p.R475*). We provide an overview of previously reported clinical features and highlight common symptoms and variability of MRT13. Common findings are intellectual disability and absent speech, and frequently microcephaly, motor delay and pathological findings on MRI including diminished cerebral white matter volume are present. Mutations in TRAPPC9 should be considered in non-syndromic autosomal recessive intellectual disability with severe speech disorder.
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Affiliation(s)
- Ansar A Abbasi
- Department of Zoology, Mirpur University of Science and Technology (MUST), Mirpur, Pakistan
| | - Kathrin Blaesius
- Charité - Universitätsmedizin Berlin, Institute of Neuroanatomy and Cell Biology, Berlin, Germany.,Berlin Insitute of Health (BIH), Anna-Louisa-Karsch Strasse 2, 10178, Berlin, Germany.,Charité - Universitätsmedizin Berlin, Department of Pediatric Neurology, Berlin, Germany
| | - Hao Hu
- Guangzhou Women and Children's Medical Center, Guangzhou, China
| | - Zahid Latif
- Department of Zoology, University of Azad Jammu and Kashmir Muzaffarabad, Muzaffarabad, Pakistan
| | - Sylvie Picker-Minh
- Charité - Universitätsmedizin Berlin, Institute of Neuroanatomy and Cell Biology, Berlin, Germany.,Berlin Insitute of Health (BIH), Anna-Louisa-Karsch Strasse 2, 10178, Berlin, Germany.,Charité - Universitätsmedizin Berlin, Department of Pediatric Neurology, Berlin, Germany.,Department of Pediatric Neurology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Muhammad N Khan
- Department of Zoology, University of Azad Jammu and Kashmir Muzaffarabad, Muzaffarabad, Pakistan
| | - Sundas Farooq
- Department of Zoology, Mirpur University of Science and Technology (MUST), Mirpur, Pakistan
| | - Muzammil A Khan
- Gomal Centre of Biochemistry and Biotechnology (GCBB), Gomal University, Dera Ismail Khan, Pakistan
| | - Angela M Kaindl
- Charité - Universitätsmedizin Berlin, Institute of Neuroanatomy and Cell Biology, Berlin, Germany.,Berlin Insitute of Health (BIH), Anna-Louisa-Karsch Strasse 2, 10178, Berlin, Germany.,Charité - Universitätsmedizin Berlin, Department of Pediatric Neurology, Berlin, Germany.,Department of Pediatric Neurology, Charité-Universitätsmedizin Berlin, Berlin, Germany
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19
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Mortreux J, Busa T, Germain DP, Nadeau G, Puechberty J, Coubes C, Gatinois V, Cacciagli P, Duffourd Y, Pinard JM, Tevissen H, Villard L, Sanlaville D, Philip N, Missirian C. The role of CNVs in the etiology of rare autosomal recessive disorders: the example of TRAPPC9-associated intellectual disability. Eur J Hum Genet 2017; 26:143-148. [PMID: 29187737 DOI: 10.1038/s41431-017-0018-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 09/07/2017] [Accepted: 09/09/2017] [Indexed: 12/23/2022] Open
Abstract
INTRODUCTION A large number of genes involved in autosomal recessive forms of intellectual disability (ID) were identified over the past few years through whole-exome sequencing (WES) or whole-genome sequencing in consanguineous families. Disease-associated variants in TRAPPC9 were reported in eight multiplex consanguineous sibships from different ethnic backgrounds, and led to the delineation of the phenotype. Affected patients have microcephaly, obesity, normal motor development, severe ID, and language impairment and brain anomalies. PATIENTS We report six new patients recruited through a national collaborative network. RESULTS In the two patients heterozygous for a copy-number variation (CNV), the phenotype was clinically relevant with regard to the literature, which prompted to sequence the second allele, leading to identification of disease-associated variants in both. The third patient was homozygote for an intragenic TRAPPC9 CNV. The phenotype of the patients reported was concordant with the literature. Recent reports emphasized the role of CNVs in the etiology of rare recessive disorders. CONCLUSION This study demonstrates that CNVs significantly contribute to the mutational spectrum of TRAPPC9 gene, and also confirms the interest of combining WES with CNV analysis to provide a molecular diagnosis to patients with rare Mendelian disorders.
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Affiliation(s)
- Jérémie Mortreux
- Département de Génétique Médicale, APHM, CHU Timone Enfants, Marseille, France.
| | - Tiffany Busa
- Département de Génétique Médicale, APHM, CHU Timone Enfants, Marseille, France
| | - Dominique P Germain
- Division of Medical Genetics, University of Versailles, 78180, Montigny, France.,CHU Raymond Poincaré (AP-HP), Garches, France
| | - Gwenaël Nadeau
- UF de génétique chromosomique, Centre hospitalier métropole Savoie, Chambéry, France
| | - Jacques Puechberty
- Département de Génétique Médicale, Maladies rares et Médecine Personnalisée, CHU de Montpellier, France
| | - Christine Coubes
- Département de Génétique Médicale, Maladies rares et Médecine Personnalisée, CHU de Montpellier, France
| | - Vincent Gatinois
- Laboratoire de Génétique Chromosomique, CHU de Montpellier, France
| | | | - Yannis Duffourd
- Fédération Hospitalo-Universitaire Médecine Translationnelle et Anomalies du Développement (FHU TRANSLAD), CHU de Dijon et Université de Bourgogne-Franche Comté, Dijon, France.,Equipe d'Accueil 42271, Génétique des Anomalies du Développement, Université de Bourgogne, Dijon, France
| | - Jean-Marc Pinard
- Division of Neuropediatrics, CHU Raymond Poincaré (AP-HP), Garches, France
| | | | - Laurent Villard
- Aix Marseille Université, GMGF, Inserm, UMR_S 910, Marseille, France
| | - Damien Sanlaville
- Department of Genetics, Lyon University Hospitals, Lyon, France.,Lyon Neuroscience Research Centre, CNRS UMR5292, Inserm U1028, Lyon, France.,Claude Bernard Lyon I University, Lyon, France
| | - Nicole Philip
- Département de Génétique Médicale, APHM, CHU Timone Enfants, Marseille, France.,Aix Marseille Université, GMGF UMR_S 910, Marseille, France
| | - Chantal Missirian
- Département de Génétique Médicale, APHM, CHU Timone Enfants, Marseille, France
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20
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Di Gregorio E, Riberi E, Belligni EF, Biamino E, Spielmann M, Ala U, Calcia A, Bagnasco I, Carli D, Gai G, Giordano M, Guala A, Keller R, Mandrile G, Arduino C, Maffè A, Naretto VG, Sirchia F, Sorasio L, Ungari S, Zonta A, Zacchetti G, Talarico F, Pappi P, Cavalieri S, Giorgio E, Mancini C, Ferrero M, Brussino A, Savin E, Gandione M, Pelle A, Giachino DF, De Marchi M, Restagno G, Provero P, Cirillo Silengo M, Grosso E, Buxbaum JD, Pasini B, De Rubeis S, Brusco A, Ferrero GB. Copy number variants analysis in a cohort of isolated and syndromic developmental delay/intellectual disability reveals novel genomic disorders, position effects and candidate disease genes. Clin Genet 2017; 92:415-422. [PMID: 28295210 DOI: 10.1111/cge.13009] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Revised: 02/28/2017] [Accepted: 03/02/2017] [Indexed: 12/14/2022]
Abstract
BACKGROUND Array-comparative genomic hybridization (array-CGH) is a widely used technique to detect copy number variants (CNVs) associated with developmental delay/intellectual disability (DD/ID). AIMS Identification of genomic disorders in DD/ID. MATERIALS AND METHODS We performed a comprehensive array-CGH investigation of 1,015 consecutive cases with DD/ID and combined literature mining, genetic evidence, evolutionary constraint scores, and functional information in order to assess the pathogenicity of the CNVs. RESULTS We identified non-benign CNVs in 29% of patients. Amongst the pathogenic variants (11%), detected with a yield consistent with the literature, we found rare genomic disorders and CNVs spanning known disease genes. We further identified and discussed 51 cases with likely pathogenic CNVs spanning novel candidate genes, including genes encoding synaptic components and/or proteins involved in corticogenesis. Additionally, we identified two deletions spanning potential Topological Associated Domain (TAD) boundaries probably affecting the regulatory landscape. DISCUSSION AND CONCLUSION We show how phenotypic and genetic analyses of array-CGH data allow unraveling complex cases, identifying rare disease genes, and revealing unexpected position effects.
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Affiliation(s)
- E Di Gregorio
- University of Torino, Department of Medical Sciences, Turin, Italy.,Medical Genetics Unit, Città della Salute e della Scienza University Hospital, Turin, Italy
| | - E Riberi
- Department of Public Health and Pediatrics, University of Torino, Turin, Italy
| | - E F Belligni
- Department of Public Health and Pediatrics, University of Torino, Turin, Italy
| | - E Biamino
- Department of Public Health and Pediatrics, University of Torino, Turin, Italy
| | - M Spielmann
- Research Group Mundlos, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - U Ala
- Computational Biology Unit, Molecular Biotechnology Center (MBC), Turin, Italy.,Department of Molecular Biotechnology and Health Sciences, University of Torino, Turin, Italy
| | - A Calcia
- University of Torino, Department of Medical Sciences, Turin, Italy
| | - I Bagnasco
- Neuropsichiatria Infantile, Martini Hospital, ASL TO1, Turin, Italy
| | - D Carli
- University of Torino, Department of Medical Sciences, Turin, Italy
| | - G Gai
- Medical Genetics Unit, Città della Salute e della Scienza University Hospital, Turin, Italy
| | - M Giordano
- Department of Health Sciences, Laboratory of Genetics, University of Eastern Piedmont and Interdisciplinary Research Center of Autoimmune Diseases, Novara, Italy
| | - A Guala
- SOC Pediatria, Castelli Hospital, Verbania, Italy
| | - R Keller
- Mental Health Department, ASL TO2, Adult Autism Center, Turin, Italy
| | - G Mandrile
- Medical Genetics Unit, Città della Salute e della Scienza University Hospital, Turin, Italy.,Medical Genetics, San Luigi Gonzaga University Hospital, Orbassano (TO), Italy
| | - C Arduino
- Medical Genetics Unit, Città della Salute e della Scienza University Hospital, Turin, Italy
| | - A Maffè
- Molecular Biology and Genetics Unit, Santa Croce e Carle Hospital, Cuneo, Italy
| | - V G Naretto
- Medical Genetics Unit, Città della Salute e della Scienza University Hospital, Turin, Italy
| | - F Sirchia
- Molecular Biology and Genetics Unit, Santa Croce e Carle Hospital, Cuneo, Italy
| | - L Sorasio
- Pediatrics, Santa Croce e Carle Hospital, Cuneo, Italy
| | - S Ungari
- Molecular Biology and Genetics Unit, Santa Croce e Carle Hospital, Cuneo, Italy
| | - A Zonta
- Medical Genetics Unit, Città della Salute e della Scienza University Hospital, Turin, Italy
| | - G Zacchetti
- Medical Genetics Unit, Città della Salute e della Scienza University Hospital, Turin, Italy.,Department of Health Sciences, Laboratory of Genetics, University of Eastern Piedmont and Interdisciplinary Research Center of Autoimmune Diseases, Novara, Italy
| | - F Talarico
- Medical Genetics Unit, Città della Salute e della Scienza University Hospital, Turin, Italy
| | - P Pappi
- Medical Genetics Unit, Città della Salute e della Scienza University Hospital, Turin, Italy
| | - S Cavalieri
- University of Torino, Department of Medical Sciences, Turin, Italy
| | - E Giorgio
- University of Torino, Department of Medical Sciences, Turin, Italy
| | - C Mancini
- University of Torino, Department of Medical Sciences, Turin, Italy
| | - M Ferrero
- University of Torino, Department of Medical Sciences, Turin, Italy
| | - A Brussino
- University of Torino, Department of Medical Sciences, Turin, Italy
| | - E Savin
- Medical Genetics Unit, Città della Salute e della Scienza University Hospital, Turin, Italy
| | - M Gandione
- Department of Neuropsychiatry, University of Torino, Turin, Italy
| | - A Pelle
- Medical Genetics, San Luigi Gonzaga University Hospital, Orbassano (TO), Italy.,Department of Clinical and Biological Sciences, University of Torino, Turin, Italy
| | - D F Giachino
- Medical Genetics, San Luigi Gonzaga University Hospital, Orbassano (TO), Italy.,Department of Clinical and Biological Sciences, University of Torino, Turin, Italy
| | - M De Marchi
- Medical Genetics, San Luigi Gonzaga University Hospital, Orbassano (TO), Italy.,Department of Clinical and Biological Sciences, University of Torino, Turin, Italy
| | - G Restagno
- Laboratory of Molecular Genetics, Città della Salute e della Scienza University Hospital, Turin, Italy
| | - P Provero
- Computational Biology Unit, Molecular Biotechnology Center (MBC), Turin, Italy.,Department of Molecular Biotechnology and Health Sciences, University of Torino, Turin, Italy
| | - M Cirillo Silengo
- Department of Public Health and Pediatrics, University of Torino, Turin, Italy
| | - E Grosso
- Medical Genetics Unit, Città della Salute e della Scienza University Hospital, Turin, Italy
| | - J D Buxbaum
- Seaver Autism Center for Research and Treatment, Icahn School of Medicine at Mount Sinai, New York, New York.,Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York.,Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, New York.,Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York.,Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York.,Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, New York
| | - B Pasini
- Molecular Biology and Genetics Unit, Santa Croce e Carle Hospital, Cuneo, Italy
| | - S De Rubeis
- Seaver Autism Center for Research and Treatment, Icahn School of Medicine at Mount Sinai, New York, New York.,Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York
| | - A Brusco
- University of Torino, Department of Medical Sciences, Turin, Italy.,Medical Genetics Unit, Città della Salute e della Scienza University Hospital, Turin, Italy
| | - G B Ferrero
- Department of Public Health and Pediatrics, University of Torino, Turin, Italy
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21
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Array comparative genomic hybridization and genomic sequencing in the diagnostics of the causes of congenital anomalies. J Appl Genet 2016; 58:185-198. [PMID: 27858254 DOI: 10.1007/s13353-016-0376-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Revised: 10/19/2016] [Accepted: 11/03/2016] [Indexed: 12/17/2022]
Abstract
The aim of this review is to provide the current state of knowledge about the usefulness of modern genetic technologies in uncovering the causality of isolated and multiple congenital anomalies. Array comparative genomic hybridization and next-generation sequencing have revolutionized the clinical approach to patients with these phenotypes. Both technologies enable early diagnosis, especially in clinically challenging newborn populations, and help to uncover genetic defects associated with various phenotypes. The application of both complementary methods could assist in identifying many variants that may simultaneously be involved in the development of a number of isolated or multiple congenital anomalies. Both technologies carry serious variant misinterpretation risks as well. Therefore, the methods of variant classification and accessible variant databases are mentioned. A useful strategy of clinical genetic testing with the application of both methodologies is presented. Finally, future directions and challenges are briefly commented on in this review.
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Testing the Complex Child: CGH Array, WES, Clinical Exome, WGS. CURRENT PEDIATRICS REPORTS 2016. [DOI: 10.1007/s40124-016-0111-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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