1
|
Yu B, Chen J, Yang S, Wang H, Xiao Y, Liu S. Case Report: Whole exome sequencing identifies compound heterozygous variants in the TRAPPC9 gene in a child with developmental delay. Front Genet 2024; 15:1415194. [PMID: 39184350 PMCID: PMC11341409 DOI: 10.3389/fgene.2024.1415194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Accepted: 07/29/2024] [Indexed: 08/27/2024] Open
Abstract
Background Developmental delay in children under 5 years old, which occurs globally with an incidence of 10%-15%, is caused by multiple factors including genetics, prenatal conditions, perinatal complications, postnatal influences, social factors, and nutritional deficiencies. Gene variants such as EFNB1, MECP2 and TRAPPC9 play a significant role in protein deformation and downregulation of nuclear factor κB (NF-κB) activity. Methods A 3-year-old girl, who exhibits poor gross motor skills, personal-social development, auditory language, hand-eye coordination, and visual performance, was diagnosed with global developmental delay. Trio whole exome sequencing was conducted to identify the genetic etiology of her condition. The identified genetic etiology was then validated through Sanger sequencing and quantitative polymerase chain reaction (qPCR). Results Genetic analysis revealed that the patient had compound heterozygous variants in the TRAPPC9 gene. These include a c.1928del frameshift variant inherited from the unaffected father and a deletion in exon 12 inherited from the unaffected mother. According to the American College of Medical Genetics (ACMG) guidelines, these variants were classified as "likely pathogenic". Conclusion The study revealed that compound heterozygous TRAPPC9 gene variants cause developmental delay in a Chinese girl. These variants have been classified as having significant pathogenic effect according to the ACMG criteria, suggesting a recessive genetic pattern and highlighting the importance of prenatal testing for future offspring. Furthermore, our findings expand the genotype spectrum of the TRAPPC9 gene, and provide more comprehensive information regarding genetic counseling for children experiencing developmental delay.
Collapse
Affiliation(s)
- Bingxuan Yu
- Department of Medical Genetics/Prenatal Diagnostic Center, West China Second University Hospital, Sichuan University, Chengdu, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, China
| | - Jing Chen
- Department of Medical Genetics/Prenatal Diagnostic Center, West China Second University Hospital, Sichuan University, Chengdu, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, China
| | - Shuo Yang
- Department of Medical Genetics/Prenatal Diagnostic Center, West China Second University Hospital, Sichuan University, Chengdu, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, China
| | - He Wang
- Department of Medical Genetics/Prenatal Diagnostic Center, West China Second University Hospital, Sichuan University, Chengdu, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, China
| | - Yuanyuan Xiao
- Department of Medical Genetics/Prenatal Diagnostic Center, West China Second University Hospital, Sichuan University, Chengdu, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, China
| | - Shanling Liu
- Department of Medical Genetics/Prenatal Diagnostic Center, West China Second University Hospital, Sichuan University, Chengdu, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, China
| |
Collapse
|
2
|
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.
Collapse
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.
| |
Collapse
|
3
|
Aljuraysi S, Platt M, Pulix M, Poptani H, Plagge A. Microcephaly with a disproportionate hippocampal reduction, stem cell loss and neuronal lipid droplet symptoms in Trappc9 KO mice. Neurobiol Dis 2024; 192:106431. [PMID: 38331351 DOI: 10.1016/j.nbd.2024.106431] [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] [Received: 12/04/2023] [Revised: 01/23/2024] [Accepted: 02/04/2024] [Indexed: 02/10/2024] Open
Abstract
Mutations of the human TRAFFICKING PROTEIN PARTICLE COMPLEX SUBUNIT 9 (TRAPPC9) cause a neurodevelopmental disorder characterised by microcephaly and intellectual disability. Trappc9 constitutes a subunit specific to the intracellular membrane-associated TrappII complex. The TrappII complex interacts with Rab11 and Rab18, the latter being specifically associated with lipid droplets (LDs). Here we used non-invasive imaging to characterise Trappc9 knock-out (KO) mice as a model of the human hereditary disorder. KOs developed postnatal microcephaly with many grey and white matter regions being affected. In vivo magnetic resonance imaging (MRI) identified a disproportionately stronger volume reduction in the hippocampus, which was associated with a significant loss of Sox2-positive neural stem and progenitor cells. Diffusion tensor imaging indicated a reduced organisation or integrity of white matter areas. Trappc9 KOs displayed behavioural abnormalities in several tests related to exploration, learning and memory. Trappc9-deficient primary hippocampal neurons accumulated a larger LD volume per cell following Oleic Acid stimulation, and the coating of LDs by Perilipin-2 was much reduced. Additionally, Trappc9 KOs developed obesity, which was significantly more severe in females than in males. Our findings indicate that, beyond previously reported Rab11-related vesicle transport defects, dysfunctions in LD homeostasis might contribute to the neurobiological symptoms of Trappc9 deficiency.
Collapse
Affiliation(s)
- Sultan Aljuraysi
- Department of Biochemistry, Cell and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, UK; Department of Physiology, College of Medicine, King Saud University, Riyadh, Saudi Arabia
| | - Mark Platt
- Department of Molecular and Clinical Cancer Medicine, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, UK; Centre for Preclinical Imaging, University of Liverpool, Liverpool, UK
| | - Michela Pulix
- Department of Biochemistry, Cell and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, UK
| | - Harish Poptani
- Department of Molecular and Clinical Cancer Medicine, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, UK; Centre for Preclinical Imaging, University of Liverpool, Liverpool, UK.
| | - Antonius Plagge
- Department of Biochemistry, Cell and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, UK; Centre for Preclinical Imaging, University of Liverpool, Liverpool, UK.
| |
Collapse
|
4
|
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.
Collapse
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
| |
Collapse
|
5
|
Hu M, Bodnar B, Zhang Y, Xie F, Li F, Li S, Zhao J, Zhao R, Gedupoori N, Mo Y, Lin L, Li X, Meng W, Yang X, Wang H, Barbe MF, Srinivasan S, Bethea JR, Mo X, Xu H, Hu W. Defective neurite elongation and branching in Nibp/Trappc9 deficient zebrafish and mice. Int J Biol Sci 2023; 19:3226-3248. [PMID: 37416774 PMCID: PMC10321293 DOI: 10.7150/ijbs.78489] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 06/06/2023] [Indexed: 07/08/2023] Open
Abstract
Loss of function in transport protein particles (TRAPP) links a new set of emerging genetic disorders called "TRAPPopathies". One such disorder is NIBP syndrome, characterized by microcephaly and intellectual disability, and caused by mutations of NIBP/TRAPPC9, a crucial and unique member of TRAPPII. To investigate the neural cellular/molecular mechanisms underlying microcephaly, we developed Nibp/Trappc9-deficient animal models using different techniques, including morpholino knockdown and CRISPR/Cas mutation in zebrafish and Cre/LoxP-mediated gene targeting in mice. Nibp/Trappc9 deficiency impaired the stability of the TRAPPII complex at actin filaments and microtubules of neurites and growth cones. This deficiency also impaired elongation and branching of neuronal dendrites and axons, without significant effects on neurite initiation or neural cell number/types in embryonic and adult brains. The positive correlation of TRAPPII stability and neurite elongation/branching suggests a potential role for TRAPPII in regulating neurite morphology. These results provide novel genetic/molecular evidence to define patients with a type of non-syndromic autosomal recessive intellectual disability and highlight the importance of developing therapeutic approaches targeting the TRAPPII complex to cure TRAPPopathies.
Collapse
Affiliation(s)
- Min Hu
- Laboratory of Stem Cell Biology, State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, China
| | - Brittany Bodnar
- Center for Metabolic Disease Research, Department of Pathalogy and Laboratory Medicine, Temple University Lewis Katz School of Medicine, Philadelphia, PA, USA
| | - 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 610052, China
| | - Fangxin Xie
- Center for Stem Cell Research and Application, Institute of Blood Transfusion, Chinese Academy of Medical Sciences & Peking Union Medical College (CAMS & PUMC), Chengdu 610052, China
- Department of Clinical Laboratory, Xi'an NO. 3 Hospital, Xi'an, Shaanxi, 710018, China
| | - Fang Li
- Center for Metabolic Disease Research, Department of Pathalogy and Laboratory Medicine, Temple University Lewis Katz School of Medicine, Philadelphia, PA, USA
| | - Siying Li
- Laboratory of Stem Cell Biology, State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, China
| | - Jin Zhao
- Laboratory of Stem Cell Biology, State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, China
| | - Ruotong Zhao
- Center for Metabolic Disease Research, Department of Pathalogy and Laboratory Medicine, Temple University Lewis Katz School of Medicine, Philadelphia, PA, USA
| | - Naveen Gedupoori
- Center for Metabolic Disease Research, Department of Pathalogy and Laboratory Medicine, Temple University Lewis Katz School of Medicine, Philadelphia, PA, USA
| | - Yifan Mo
- Center for Metabolic Disease Research, Department of Pathalogy and Laboratory Medicine, Temple University Lewis Katz School of Medicine, Philadelphia, PA, USA
| | - Lanyi Lin
- Center for Metabolic Disease Research, Department of Pathalogy and Laboratory Medicine, Temple University Lewis Katz School of Medicine, Philadelphia, PA, USA
| | - Xue Li
- Laboratory of Stem Cell Biology, State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, China
| | - Wentong Meng
- Laboratory of Stem Cell Biology, State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, China
| | - Xiaofeng Yang
- Center for Metabolic Disease Research, Department of Pathalogy and Laboratory Medicine, Temple University Lewis Katz School of Medicine, Philadelphia, PA, USA
| | - Hong Wang
- Center for Metabolic Disease Research, Department of Pathalogy and Laboratory Medicine, Temple University Lewis Katz School of Medicine, Philadelphia, PA, USA
| | - Mary F. Barbe
- Center for Metabolic Disease Research, Department of Pathalogy and Laboratory Medicine, Temple University Lewis Katz School of Medicine, Philadelphia, PA, USA
| | - Shanthi Srinivasan
- Division of Digestive Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, USA
| | - John R. Bethea
- Department of Biology, Drexel University, Philadelphia, PA, USA
| | - Xianming Mo
- Laboratory of Stem Cell Biology, State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, China
| | - Hong Xu
- Laboratory of Stem Cell Biology, State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, China
| | - Wenhui Hu
- Laboratory of Stem Cell Biology, State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, China
- Center for Metabolic Disease Research, Department of Pathalogy and Laboratory Medicine, Temple University Lewis Katz School of Medicine, Philadelphia, PA, USA
| |
Collapse
|
6
|
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.
Collapse
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
| |
Collapse
|
7
|
Dattilo V, Ulivi S, Minelli A, La Bianca M, Giacopuzzi E, Bortolomasi M, Bignotti S, Gennarelli M, Gasparini P, Concas MP. Genome-wide association studies on Northern Italy isolated populations provide further support concerning genetic susceptibility for major depressive disorder. World J Biol Psychiatry 2023; 24:135-148. [PMID: 35615967 DOI: 10.1080/15622975.2022.2082523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
OBJECTIVES Major depressive disorder (MDD) is a psychiatric disorder with pathogenesis influenced by both genetic and environmental factors. To date, the molecular-level understanding of its aetiology remains unclear. Thus, we aimed to identify genetic variants and susceptibility genes for MDD with a genome-wide association study (GWAS) approach. METHODS We performed a meta-analysis of GWASs and a gene-based analysis on two Northern Italy isolated populations (cases/controls n = 166/472 and 33/320), followed by replication and polygenic risk score (PRS) analyses in Italian independent samples (cases n = 464, controls n = 339). RESULTS We identified two novel MDD-associated genes, KCNQ5 (lead SNP rs867262, p = 3.82 × 10-9) and CTNNA2 (rs6729523, p = 1.25 × 10-8). The gene-based analysis revealed another six genes (p < 2.703 × 10-6): GRM7, CTNT4, SNRK, SRGAP3, TRAPPC9, and FHIT. No replication of the genome-wide significant SNPs was found in the independent cohort, even if 14 SNPs around CTNNA2 showed association with MDD and related phenotypes at the nominal level of p (<0.05). Furthermore, the PRS model developed in the discovery cohort discriminated cases and controls in the replication cohort. CONCLUSIONS Our work suggests new possible genes associated with MDD, and the PRS analysis confirms the polygenic nature of this disorder. Future studies are required to better understand the role of these findings in MDD.
Collapse
Affiliation(s)
- Vincenzo Dattilo
- Genetics Unit, IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy
| | - Sheila Ulivi
- Institute for Maternal and Child Health-IRCCS Burlo Garofolo, Trieste, Italy
| | - Alessandra Minelli
- Genetics Unit, IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy.,Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Martina La Bianca
- Institute for Maternal and Child Health-IRCCS Burlo Garofolo, Trieste, Italy
| | - Edoardo Giacopuzzi
- Wellcome Centre for Human Genetics, Oxford University, Oxford, UK.,NIHR Oxford Biomedical Research Centre, Oxford, UK
| | | | - Stefano Bignotti
- Unit of Psychiatry, IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy
| | - Massimo Gennarelli
- Genetics Unit, IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy.,Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Paolo Gasparini
- Institute for Maternal and Child Health-IRCCS Burlo Garofolo, Trieste, Italy.,Department of Medicine, Surgery and Health Science, University of Trieste, Trieste, Italy
| | - Maria Pina Concas
- Institute for Maternal and Child Health-IRCCS Burlo Garofolo, Trieste, Italy
| |
Collapse
|
8
|
Wongpaiboonwattana W, Hnoonual A, Limprasert P. Association between 19-bp Insertion/Deletion Polymorphism of Dopamine β-Hydroxylase and Autism Spectrum Disorder in Thai Patients. Medicina (B Aires) 2022; 58:medicina58091228. [PMID: 36143905 PMCID: PMC9504840 DOI: 10.3390/medicina58091228] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 09/01/2022] [Accepted: 09/02/2022] [Indexed: 11/30/2022] Open
Abstract
Background and Objectives: Autism spectrum disorder (ASD) is a neurodevelopmental disorder the cause of which is not fully known. Genetic factors are believed to play a major role in the etiology of ASD. However, genetic factors have been identified in only some cases, and other causes remain to be identified. This study aimed to identify potential associations between ASD and the 19-bp insertion/deletion polymorphism in the dopamine beta-hydroxylase (DBH) gene which plays a crucial role in the metabolism of neurotransmitters. Materials and Methods: The 19-bp insertion/deletion polymorphism upstream of the DBH gene was analyzed for associations in 177 ASD patients and 250 healthy controls. Family-based analysis was performed in family trios of each patient using the transmission disequilibrium test to investigate the potential contributions of this DBH polymorphism to ASD. Results: The frequency of the 19-bp insertion allele was significantly higher in the patient group compared to the controls (0.624 vs. 0.556, respectively; p = 0.046). The frequency of the insertion/insertion genotype was also higher in the patient group (0.378 vs. 0.288, respectively) but without statistical significance (p = 0.110). The family-based analysis showed an association between patient families and the insertion allele when only families of male participants were analyzed (73 vs. 48 events; OR 1.521; 95% CI 1.057–2.189; p = 0.023). Conclusions: This population-based analysis found an association between the 19-bp insertion allele of the DBH gene and ASD. No association at the genotype level was found. The family-based analysis found an association between the insertion allele and ASD when the analysis was performed on male participants only, suggesting a linkage between the DBH locus and ASD.
Collapse
Affiliation(s)
| | - Areerat Hnoonual
- Department of Pathology and Genomic Medicine Center, Faculty of Medicine, Prince of Songkla University, Songkhla 90110, Thailand
| | - Pornprot Limprasert
- Department of Pathology and Genomic Medicine Center, Faculty of Medicine, Prince of Songkla University, Songkhla 90110, Thailand
- Correspondence: or
| |
Collapse
|
9
|
Cui P, Wang W, Zhang D, Li C, Huang Y, Ma Z, Wang X, Zhao L, Zhang Y, Yang X, Xu D, Cheng J, Li X, Zeng X, Zhao Y, Li W, Wang J, Lin C, Zhou B, Liu J, Zhai R, Zhang X. Identification of TRAPPC9 and BAIAP2 Gene Polymorphisms and Their Association With Fat Deposition-Related Traits in Hu Sheep. Front Vet Sci 2022; 9:928375. [PMID: 35865874 PMCID: PMC9295322 DOI: 10.3389/fvets.2022.928375] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 06/14/2022] [Indexed: 12/12/2022] Open
Abstract
Fat deposition is an important economic trait that is closely related to feed efficiency and carcass performance in livestock. In this study, the fat deposition-related traits of 1,293 Hu sheep were measured and descriptive statistical analysis was conducted. The results showed that the coefficient of variation of all fat deposition-related traits was higher than 24%. In addition, single nucleotide polymorphisms and the expression characteristics of TRAPPC9 (encoding trafficking protein particle complex subunit 9) and BAIAP2 (encoding brain-specific Angiogenesis inhibitor 1-associated protein 2) genes in Hu sheep were detected using PCR amplification, Sanger sequencing, KASPar genotyping, and quantitative real-time reverse transcription PCR (qRT-PCR). The associations between SNPs and fat deposition-related traits were also analyzed. Two intronic mutations, TRAPPC9 g.57654 A > G and BAIAP2 g.46061 C > T, were identified in Hu sheep. The result of association analysis showed that TRAPPC9 g.57654 A > G and BAIAP2 g.46061 C > T were both significantly associated with the weight of tail fat, tail fat relative weight (body weight), and tail fat relative weight (carcass) (P < 0.05). Comprehensive effects analysis showed that there were significant differences between the combined genotypes and tail fat and perirenal fat deposition. Moreover, qRT-PCR analysis showed that TRAPPC9 and BAIAP2 are widely expressed, and their expression levels were significantly higher in the small-tail group compared with those in the big-tail group (P < 0.01). These results provided important candidate molecular markers that could be used in strategies to reduce tail fat deposition in Hu sheep.
Collapse
Affiliation(s)
- Panpan Cui
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Weimin Wang
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
- The State Key Laboratory of Grassland Agro-Ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, China
| | - Deyin Zhang
- The State Key Laboratory of Grassland Agro-Ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, China
| | - Chong Li
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Yongliang Huang
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Zongwu Ma
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Xiaojuan Wang
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Liming Zhao
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Yukun Zhang
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Xiaobin Yang
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Dan Xu
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Jiangbo Cheng
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Xiaolong Li
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Xiwen Zeng
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Yuan Zhao
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Wenxin Li
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Jianghui Wang
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Changchun Lin
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Bubo Zhou
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Jia Liu
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Rui Zhai
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Xiaoxue Zhang
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
- *Correspondence: Xiaoxue Zhang
| |
Collapse
|
10
|
Trappc9 Deficiency Impairs the Plasticity of Stem Cells. Int J Mol Sci 2022; 23:ijms23094900. [PMID: 35563289 PMCID: PMC9101649 DOI: 10.3390/ijms23094900] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 04/24/2022] [Accepted: 04/25/2022] [Indexed: 02/04/2023] Open
Abstract
Genetic mutations of trappc9 cause intellectual disability with the atrophy of brain structures and variable obesity by poorly understood mechanisms. Trappc9-deficient mice develop phenotypes resembling pathological changes in humans and appear overweight shortly after weaning, and thus are useful for studying the pathogenesis of obesity. Here, we investigated the effects of trappc9 deficiency on the proliferation and differentiation capacity of adipose-derived stem cells (ASCs). We isolated ASCs from mice before overweight was developed and found that trappc9-null ASCs exhibited signs of premature senescence and cell death. While the lineage commitment was retained, trappc9-null ASCs preferred adipogenic differentiation. We observed a profound accumulation of lipid droplets in adipogenic cells derived from trappc9-deficient ASCs and marked differences in the distribution patterns and levels of calcium deposited in osteoblasts obtained from trappc9-null ASCs. Biochemical studies revealed that trappc9 deficiency resulted in an upregulated expression of rab1, rab11, and rab18, and agitated autophagy in ASCs. Moreover, we found that the content of neural stem cells in both the subventricular zone of the lateral ventricle and the subgranular zone of the dentate gyrus vastly declined in trappc9-null mice. Collectively, our results suggest that obesity, as well as brain structure hypoplasia induced by the deficiency of trappc9, involves an impairment in the plasticity of stem cells.
Collapse
|
11
|
TRAPPC9-CDG: A novel congenital disorder of glycosylation with dysmorphic features and intellectual disability. Genet Med 2022; 24:894-904. [PMID: 35042660 DOI: 10.1016/j.gim.2021.12.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 12/15/2021] [Accepted: 12/16/2021] [Indexed: 02/07/2023] Open
Abstract
PURPOSE TRAPPC9 deficiency is an autosomal recessive disorder mainly associated with intellectual disability (ID), microcephaly, and obesity. Previously, TRAPPC9 deficiency has not been associated with biochemical abnormalities. METHODS Exome sequencing was performed in 3 individuals with ID and dysmorphic features. N-Glycosylation analyses were performed in the patients' blood samples to test for possible congenital disorder of glycosylation (CDG). TRAPPC9 gene, TRAPPC9 protein expression, and N-glycosylation markers were assessed in patient fibroblasts. Complementation with wild-type TRAPPC9 and immunofluorescence studies to assess TRAPPC9 expression and localization were performed. The metabolic consequences of TRAPPC9 deficiency were evaluated using tracer metabolomics. RESULTS All 3 patients carried biallelic missense variants in TRAPPC9 and presented with an N-glycosylation defect in blood, consistent with CDG type I. Extensive investigations in patient fibroblasts corroborated TRAPPC9 deficiency and an N-glycosylation defect. Tracer metabolomics revealed global metabolic changes with several affected glycosylation-related metabolites. CONCLUSION We identified 3 TRAPPC9 deficient patients presenting with ID, dysmorphic features, and abnormal glycosylation. On the basis of our findings, we propose that TRAPPC9 deficiency could lead to a CDG (TRAPPC9-CDG). The finding of abnormal glycosylation in these patients is highly relevant for diagnosis, further elucidation of the pathophysiology, and management of the disease.
Collapse
|
12
|
Rawlins LE, Almousa H, Khan S, Collins SC, Milev MP, Leslie J, Saint-Dic D, Khan V, Hincapie AM, Day JO, McGavin L, Rowley C, Harlalka GV, Vancollie VE, Ahmad W, Lelliott CJ, Gul A, Yalcin B, Crosby AH, Sacher M, Baple EL. Biallelic variants in TRAPPC10 cause a microcephalic TRAPPopathy disorder in humans and mice. PLoS Genet 2022; 18:e1010114. [PMID: 35298461 PMCID: PMC8963566 DOI: 10.1371/journal.pgen.1010114] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Revised: 03/29/2022] [Accepted: 02/20/2022] [Indexed: 11/25/2022] Open
Abstract
The highly evolutionarily conserved transport protein particle (TRAPP) complexes (TRAPP II and III) perform fundamental roles in subcellular trafficking pathways. Here we identified biallelic variants in TRAPPC10, a component of the TRAPP II complex, in individuals with a severe microcephalic neurodevelopmental disorder. Molecular studies revealed a weakened interaction between mutant TRAPPC10 and its putative adaptor protein TRAPPC2L. Studies of patient lymphoblastoid cells revealed an absence of TRAPPC10 alongside a concomitant absence of TRAPPC9, another key TRAPP II complex component associated with a clinically overlapping neurodevelopmental disorder. The TRAPPC9/10 reduction phenotype was recapitulated in TRAPPC10-/- knockout cells, which also displayed a membrane trafficking defect. Notably, both the reduction in TRAPPC9 levels and the trafficking defect in these cells could be rescued by wild type but not mutant TRAPPC10 gene constructs. Moreover, studies of Trappc10-/- knockout mice revealed neuroanatomical brain defects and microcephaly, paralleling findings seen in the human condition as well as in a Trappc9-/- mouse model. Together these studies confirm autosomal recessive TRAPPC10 variants as a cause of human disease and define TRAPP-mediated pathomolecular outcomes of importance to TRAPPC9 and TRAPPC10 mediated neurodevelopmental disorders in humans and mice. Microcephalic neurodevelopmental disorders are a group of conditions that are often inherited in families, involving small head size and abnormal brain development and function. This often results in delayed development of an affected child, affecting their movement, language and/or non-verbal communication and learning, as well as seizures and neuropsychiatric problems. A group of proteins called the transport protein particles (TRAPPs) are important for the transport of cargos inside cells. Alterations within a number of the TRAPP proteins have previously been associated with human inherited diseases called the ‘TRAPPopathies’, which involve neurodevelopmental and skeletal abnormalities. Here we show that TRAPPC10 gene alterations cause a new TRAPPopathy microcephalic neurodevelopmental disorder, and we provide a detailed clinical description of the condition termed ‘TRAPPC10-related disorder’. Our studies in mice lacking the TRAPPC10 gene identified similar features to those of affected humans, including small brain size and skeletal abnormalities. Our molecular studies showed that an affected individual with an alteration in the TRAPPC10 gene has no functional TRAPPC10 protein in their cells, which in turn causes a reduction in levels of another important TRAPP molecule, TRAPPC9. Cells lacking TRAPPC10 also display abnormalities in cellular transport processes. Together our data confirm alterations in TRAPPC10 as a cause of a microcephalic neurodevelopmental disorder in both humans and mice.
Collapse
Affiliation(s)
- Lettie E. Rawlins
- RILD Wellcome Wolfson Medical Research Centre, RD&E (Wonford) NHS Foundation Trust, University of Exeter Medical School, Exeter, United Kingdom
- Peninsula Clinical Genetics Service, Royal Devon & Exeter Hospital (Heavitree), Exeter, United Kingdom
| | - Hashem Almousa
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Shazia Khan
- RILD Wellcome Wolfson Medical Research Centre, RD&E (Wonford) NHS Foundation Trust, University of Exeter Medical School, Exeter, United Kingdom
- Department of Biological Sciences, International Islamic University, Islamabad, Pakistan
| | - Stephan C. Collins
- Institute of Genetics and Molecular and Cellular Biology, Inserm, Illkirch, France
- Inserm, University of Bourgogne Franche-Comté, Dijon, France
| | - Miroslav P. Milev
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Joseph Leslie
- RILD Wellcome Wolfson Medical Research Centre, RD&E (Wonford) NHS Foundation Trust, University of Exeter Medical School, Exeter, United Kingdom
| | - Djenann Saint-Dic
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Valeed Khan
- Department of Molecular Diagnostics, Rehman Medical Institute, Peshawar, Pakistan
| | | | - Jacob O. Day
- RILD Wellcome Wolfson Medical Research Centre, RD&E (Wonford) NHS Foundation Trust, University of Exeter Medical School, Exeter, United Kingdom
- Faculty of Health, University of Plymouth, Plymouth, United Kingdom
| | - Lucy McGavin
- University Hospitals Plymouth NHS Trust, Plymouth, United Kingdom
| | | | - Gaurav V. Harlalka
- RILD Wellcome Wolfson Medical Research Centre, RD&E (Wonford) NHS Foundation Trust, University of Exeter Medical School, Exeter, United Kingdom
- Department of Pharmacology, Rajarshi Shahu College of Pharmacy, Malvihir, Buldana, India
| | | | - Wasim Ahmad
- Department of Biochemistry, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | | | - Asma Gul
- Department of Biological Sciences, International Islamic University, Islamabad, Pakistan
| | - Binnaz Yalcin
- Institute of Genetics and Molecular and Cellular Biology, Inserm, Illkirch, France
- Inserm, University of Bourgogne Franche-Comté, Dijon, France
| | - Andrew H. Crosby
- RILD Wellcome Wolfson Medical Research Centre, RD&E (Wonford) NHS Foundation Trust, University of Exeter Medical School, Exeter, United Kingdom
| | - Michael Sacher
- Department of Biology, Concordia University, Montreal, Quebec, Canada
- Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec, Canada
| | - Emma L. Baple
- RILD Wellcome Wolfson Medical Research Centre, RD&E (Wonford) NHS Foundation Trust, University of Exeter Medical School, Exeter, United Kingdom
- Peninsula Clinical Genetics Service, Royal Devon & Exeter Hospital (Heavitree), Exeter, United Kingdom
- * E-mail:
| |
Collapse
|
13
|
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.
Collapse
|
14
|
Ben Ayed I, Bouchaala W, Bouzid A, Feki W, Souissi A, Ben Nsir S, Ben Said M, Sammouda T, Majdoub F, Kharrat I, Kamoun F, Elloumi I, Kamoun H, Tlili A, Masmoudi S, Triki C. Further insights into the spectrum phenotype of TRAPPC9 and CDK5RAP2 genes, segregating independently in a large Tunisian family with intellectual disability and microcephaly. Eur J Med Genet 2021; 64:104373. [PMID: 34737153 DOI: 10.1016/j.ejmg.2021.104373] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2021] [Revised: 10/06/2021] [Accepted: 10/27/2021] [Indexed: 10/20/2022]
Abstract
Intellectual disability (ID) often co-occurs with other neurologic phenotypes making molecular diagnosis more challenging particularly in consanguineous populations with the co-segregation of more than one ID-related gene in some cases. In this study, we investigated the phenotype of three patients from a large Tunisian family with significant ID phenotypic variability and microcephaly and performed a clinical exome sequencing in two cases. We identified, within the first branch, a homozygous variant in the TRAPPC9 gene (p.Arg472Ter) in two cases presenting severe ID, absent speech, congenital/secondary microcephaly in addition to autistic features, supporting the implication of TRAPPC9 in the "secondary" autism spectrum disorders and congenital microcephaly. In the second branch, we identified a homozygous variant (p.Lys189ArgfsTer15) in the CDK5RAP2 gene associated with an heterozygous TRAPPC9 variant (p.Arg472Ter) in one case harbouring primary hereditary microcephaly (MCPH) associated with an inter-hypothalamic adhesion, mixed hearing loss, selective thinning in the retinal nerve fiber layer and parafoveal ganglion cell complex, and short stature. Our findings expand the spectrum of the recently reported neurosensorial abnormalities and revealed the variable phenotype expressivity of CDK5RAP2 defect. Our study highlights the complexity of the genetic background of microcephaly/ID and the efficiency of the exome sequencing to provide an accurate diagnosis and to improve the management and follow-up of such patients.
Collapse
Affiliation(s)
- Ikhlas Ben Ayed
- Laboratory of Molecular and Cellular Screening Processes (LPCMC), Center of Biotechnology of Sfax, University of Sfax, Tunisia; Medical Genetics Department, University Hedi Chaker Hospital of Sfax, Tunisia.
| | - Wafa Bouchaala
- Child Neurology Department, University Hedi Chaker Hospital of Sfax, Tunisia; Research Laboratory "Neuropédiatrie" LR19ES15, Sfax University, Tunisia
| | - Amal Bouzid
- Laboratory of Molecular and Cellular Screening Processes (LPCMC), Center of Biotechnology of Sfax, University of Sfax, Tunisia; Medical Research, College of Medicine, University of Sharjah, Sharjah, United Arab Emirates
| | - Wiem Feki
- Radiology Department, Hedi Chaker University Hospital, University of Sfax, Sfax, Tunisia
| | - Amal Souissi
- Laboratory of Molecular and Cellular Screening Processes (LPCMC), Center of Biotechnology of Sfax, University of Sfax, Tunisia
| | - Sihem Ben Nsir
- Child Neurology Department, University Hedi Chaker Hospital of Sfax, Tunisia; Research Laboratory "Neuropédiatrie" LR19ES15, Sfax University, Tunisia
| | - Mariem Ben Said
- Laboratory of Molecular and Cellular Screening Processes (LPCMC), Center of Biotechnology of Sfax, University of Sfax, Tunisia
| | - Takwa Sammouda
- Department of Ophthalmology, Habib Bourguiba Hospital, Sfax, Tunisia
| | - Fatma Majdoub
- Medical Genetics Department, University Hedi Chaker Hospital of Sfax, Tunisia
| | - Ines Kharrat
- Department of Otorhinolaryngology, University Habib Bourguiba Hospital of Sfax, Tunisia
| | - Fatma Kamoun
- Child Neurology Department, University Hedi Chaker Hospital of Sfax, Tunisia; Research Laboratory "Neuropédiatrie" LR19ES15, Sfax University, Tunisia
| | - Ines Elloumi
- Laboratory of Molecular and Cellular Screening Processes (LPCMC), Center of Biotechnology of Sfax, University of Sfax, Tunisia
| | - Hassen Kamoun
- Medical Genetics Department, University Hedi Chaker Hospital of Sfax, Tunisia; Laboratory of Human Molecular Genetics, LR33ES99, Faculty of Medicine of Sfax, University of Sfax, Sfax, Tunisia
| | - Abdelaziz Tlili
- Department of Applied Biology, College of Sciences, University of Sharjah, Sharjah, United Arab Emirates; Human Genetics and Stem Cell Laboratory, Research Institute of Sciences and Engineering, University of Sharjah, Sharjah, United Arab Emirates
| | - Saber Masmoudi
- Laboratory of Molecular and Cellular Screening Processes (LPCMC), Center of Biotechnology of Sfax, University of Sfax, Tunisia
| | - Chahnez Triki
- Child Neurology Department, University Hedi Chaker Hospital of Sfax, Tunisia; Research Laboratory "Neuropédiatrie" LR19ES15, Sfax University, Tunisia
| |
Collapse
|
15
|
Novel Compound Heterozygous Mutation in TRAPPC9 Gene: The Relevance of Whole Genome Sequencing. Genes (Basel) 2021; 12:genes12040557. [PMID: 33921338 PMCID: PMC8068822 DOI: 10.3390/genes12040557] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 04/07/2021] [Accepted: 04/08/2021] [Indexed: 12/17/2022] Open
Abstract
Advances in high-throughput technologies and its implementation worldwide have had a considerable impact on the elucidation of the molecular causes underlying neurodevelopmental psychiatric disorders, especially for autism spectrum disorder and intellectual disability (ID). Nevertheless, etiology remains elusive in close to 50% of cases, even in those families with multiple affected individuals, strongly hinting at a genetic cause. Here we present a case report of two siblings affected with severe ID and other comorbidities, who embarked on a genetic testing odyssey until diagnosis was reached by using whole genome sequencing (WGS). WGS identified a maternally inherited novel missense variant (NM_031466.7:c.1037G > A; p.Gly346Glu) and a paternally inherited 90 kb intragenic deletion in TRAPPC9 gene. This report demonstrates the clinical utility of WGS in patients who remain undiagnosed after whole exome sequencing.
Collapse
|
16
|
Tang BL. Defects in early secretory pathway transport machinery components and neurodevelopmental disorders. Rev Neurosci 2021; 32:851-869. [PMID: 33781010 DOI: 10.1515/revneuro-2021-0020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 03/12/2021] [Indexed: 12/23/2022]
Abstract
The early secretory pathway, provisionally comprising of vesicular traffic between the endoplasmic reticulum (ER) and the Golgi apparatus, occurs constitutively in mammalian cells. Critical for a constant supply of secretory and plasma membrane (PM) materials, the pathway is presumably essential for general cellular function and survival. Neurons exhibit a high intensity in membrane dynamics and protein/lipid trafficking, with differential and polarized trafficking towards the somatodendritic and axonal PM domains. Mutations in genes encoding early secretory pathway membrane trafficking machinery components are known to result in neurodevelopmental or neurological disorders with disease manifestation in early life. Here, such rare disorders associated with autosomal recessive mutations in coat proteins, membrane tethering complexes and membrane fusion machineries responsible for trafficking in the early secretory pathway are summarily discussed. These mutations affected genes encoding subunits of coat protein complex I and II, subunits of transport protein particle (TRAPP) complexes, members of the YIP1 domain family (YIPF) and a SNAP receptor (SNARE) family member. Why the ubiquitously present and constitutively acting early secretory pathway machinery components could specifically affect neurodevelopment is addressed, with the plausible underlying disease etiologies and neuropathological mechanisms resulting from these mutations explored.
Collapse
Affiliation(s)
- Bor Luen Tang
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, 8 Medical Drive, Singapore117597, Singapore
| |
Collapse
|
17
|
Rasool IG, Zahoor MY, Iqbal M, Anjum AA, Ashraf F, Abbas HQ, Baig HMA, Mahmood T, Shehzad W. Whole exome sequencing revealed novel variants in consanguineous Pakistani families with intellectual disability. Genes Genomics 2021; 43:503-512. [PMID: 33710595 DOI: 10.1007/s13258-021-01070-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Accepted: 02/19/2021] [Indexed: 01/19/2023]
Abstract
BACKGROUND Intellectual disability (ID) is a heterogeneous disorder affecting 1-3% of the population. Elucidation of monogenic variants for ID is a current challenge. These variants can be better demonstrated in consanguineous affected families. OBJECTIVE The study was designed to find the genetic variants of ID in consanguineous families. METHODS We analyzed five unrelated consanguineous Pakistani families affected with ID using whole exome sequencing (WES). Data was analyzed using different bioinformatics tools and software. RESULTS We mapped four variants including three novels in four different ID known genes. Each variant is found in a different family, co-segregating with a recessive pattern of inheritance. The novel variants found are; c. 2_4del (p.?) mapped in ROS1 and c. 718G>A (p.Gly240Arg) in GRM1. Another novel causative variant, c.2673del (p.Gly892Aspfs*17) identified in COL18A1 in a recessive form, a gene reported for Knobloch syndrome that manifests ID along with typical retinal abnormalities, and this phenotype was confirmed on reverse phenotyping. A mutation c.2134C>T (p.Arg712*) in TRAPPC9 has been found first time in the homozygous recessive form in our enrolled three affected siblings while it was previously reported in compound heterozygous form in a Caucasian descent. While fifth family remained unsolved. CONCLUSION These mutations in four different genes with a recessive inheritance would be a contribution to the disease variant database of this devastating disorder.
Collapse
Affiliation(s)
- Iqra Ghulam Rasool
- Molecular Biology and Forensic Laboratory, Institute of Biochemistry and Biotechnology, University of Veterinary and Animal Sciences, Lahore, 54000, Pakistan
| | - Muhammad Yasir Zahoor
- Molecular Biology and Forensic Laboratory, Institute of Biochemistry and Biotechnology, University of Veterinary and Animal Sciences, Lahore, 54000, Pakistan.
| | - Muhammad Iqbal
- Department of Biotechnology, The Islamia University of Bahawalpur, Bahawalpur, Pakistan
| | - Aftab Ahmad Anjum
- Institute of Microbiology, University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Fatima Ashraf
- Molecular Biology and Forensic Laboratory, Institute of Biochemistry and Biotechnology, University of Veterinary and Animal Sciences, Lahore, 54000, Pakistan
| | - Hafiz Qamar Abbas
- Molecular Biology and Forensic Laboratory, Institute of Biochemistry and Biotechnology, University of Veterinary and Animal Sciences, Lahore, 54000, Pakistan
| | | | - Tariq Mahmood
- Department of Statistics and Computer Science, University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Wasim Shehzad
- Molecular Biology and Forensic Laboratory, Institute of Biochemistry and Biotechnology, University of Veterinary and Animal Sciences, Lahore, 54000, Pakistan
| |
Collapse
|
18
|
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.
Collapse
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
| |
Collapse
|
19
|
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.
Collapse
Affiliation(s)
| | - Hossein Mozhdehipanah
- Department of Neurology, Bou Ali Sina Hospital, Qazvin University of Medical Sciences, Qazvin, Iran
| | | |
Collapse
|
20
|
A novel homozygous variant in the TRAPPC9 gene causing intellectual disability and autism Spectrum disorder. Meta Gene 2020. [DOI: 10.1016/j.mgene.2020.100783] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
|
21
|
Ke Y, Weng M, Chhetri G, Usman M, Li Y, Yu Q, Ding Y, Wang Z, Wang X, Sultana P, DiFiglia M, Li X. Trappc9 deficiency in mice impairs learning and memory by causing imbalance of dopamine D1 and D2 neurons. SCIENCE ADVANCES 2020; 6:6/47/eabb7781. [PMID: 33208359 PMCID: PMC7673810 DOI: 10.1126/sciadv.abb7781] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Accepted: 10/01/2020] [Indexed: 05/06/2023]
Abstract
Genetic mutations in the gene encoding transport protein particle complex 9 (trappc9), a subunit of TRAPP that acts as a guanine nucleotide exchange factor for rab proteins, cause intellectual disability with brain structural malformations by elusive mechanisms. Here, we report that trappc9-deficient mice exhibit a broad range of behavioral deficits and postnatal delay in growth of the brain. Contrary to volume decline of various brain structures, the striatum of trappc9 null mice was enlarged. An imbalance existed between dopamine D1 and D2 receptor containing neurons in the brain of trappc9-deficient mice; pharmacological manipulation of dopamine receptors improved performances of trappc9 null mice to levels of wild-type mice on cognitive tasks. Loss of trappc9 compromised the activation of rab11 in the brain and resulted in retardation of endocytic receptor recycling in neurons. Our study elicits a pathogenic mechanism and a potential treatment for trappc9-linked disorders including intellectual disability.
Collapse
Affiliation(s)
- Yuting Ke
- School of Pharmacy, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240, China
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
| | - Meiqian Weng
- Mucosal Immunology Laboratory, Combined Program in Pediatric Gastroenterology and Nutrition, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
| | - Gaurav Chhetri
- School of Pharmacy, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240, China
| | - Muhammad Usman
- School of Pharmacy, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240, China
| | - Yan Li
- School of Pharmacy, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240, China
| | - Qing Yu
- Department of Nephrology, Shanghai General Hospital, 650 Songjiang Road, Songjiang District, Shanghai 201620, China
| | - Yingzhuo Ding
- School of Pharmacy, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240, China
| | - Zejian Wang
- School of Pharmacy, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240, China
| | - Xiaolong Wang
- School of Pharmacy, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240, China
| | - Pinky Sultana
- School of Pharmacy, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240, China
| | - Marian DiFiglia
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
| | - Xueyi Li
- School of Pharmacy, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240, China.
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
| |
Collapse
|
22
|
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.
Collapse
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.
| |
Collapse
|
23
|
Liang ZS, Cimino I, Yalcin B, Raghupathy N, Vancollie VE, Ibarra-Soria X, Firth HV, Rimmington D, Farooqi IS, Lelliott CJ, Munger SC, O’Rahilly S, Ferguson-Smith AC, Coll AP, Logan DW. Trappc9 deficiency causes parent-of-origin dependent microcephaly and obesity. PLoS Genet 2020; 16:e1008916. [PMID: 32877400 PMCID: PMC7467316 DOI: 10.1371/journal.pgen.1008916] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Accepted: 06/08/2020] [Indexed: 11/30/2022] Open
Abstract
Some imprinted genes exhibit parental origin specific expression bias rather than being transcribed exclusively from one copy. The physiological relevance of this remains poorly understood. In an analysis of brain-specific allele-biased expression, we identified that Trappc9, a cellular trafficking factor, was expressed predominantly (~70%) from the maternally inherited allele. Loss-of-function mutations in human TRAPPC9 cause a rare neurodevelopmental syndrome characterized by microcephaly and obesity. By studying Trappc9 null mice we discovered that homozygous mutant mice showed a reduction in brain size, exploratory activity and social memory, as well as a marked increase in body weight. A role for Trappc9 in energy balance was further supported by increased ad libitum food intake in a child with TRAPPC9 deficiency. Strikingly, heterozygous mice lacking the maternal allele (70% reduced expression) had pathology similar to homozygous mutants, whereas mice lacking the paternal allele (30% reduction) were phenotypically normal. Taken together, we conclude that Trappc9 deficient mice recapitulate key pathological features of TRAPPC9 mutations in humans and identify a role for Trappc9 and its imprinting in controlling brain development and metabolism.
Collapse
Affiliation(s)
- Zhengzheng S. Liang
- Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, United Kingdom
| | - Irene Cimino
- MRC Metabolic Diseases Unit, Wellcome Trust-Medical Research Council Institute of Metabolic Science, University of Cambridge, Cambridge, United Kingdom
| | - Binnaz Yalcin
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Université de Strasbourg, France
| | | | | | - Ximena Ibarra-Soria
- Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, United Kingdom
| | - Helen V. Firth
- Department of Clinical Genetics, Addenbrooke’s Hospital, Cambridge, United Kingdom
| | - Debra Rimmington
- MRC Metabolic Diseases Unit, Wellcome Trust-Medical Research Council Institute of Metabolic Science, University of Cambridge, Cambridge, United Kingdom
| | - I. Sadaf Farooqi
- University of Cambridge Metabolic Research Laboratories and NIHR Cambridge Biomedical Research Centre, Addenbrooke's Hospital, Cambridge, United Kingdom
| | | | - Steven C. Munger
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
| | - Stephen O’Rahilly
- MRC Metabolic Diseases Unit, Wellcome Trust-Medical Research Council Institute of Metabolic Science, University of Cambridge, Cambridge, United Kingdom
| | | | - Anthony P. Coll
- MRC Metabolic Diseases Unit, Wellcome Trust-Medical Research Council Institute of Metabolic Science, University of Cambridge, Cambridge, United Kingdom
| | - Darren W. Logan
- Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, United Kingdom
| |
Collapse
|
24
|
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.
Collapse
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
| |
Collapse
|
25
|
Nair P, El-Bazzal L, Mansour H, Sabbagh S, Al-Ali MT, Gambarini A, Delague V, El-Hayek S, Mégarbané A. Further Delineation of the TRAPPC6B Disorder: Report on a New Family and Review. J Pediatr Genet 2019; 8:252-256. [PMID: 31687267 DOI: 10.1055/s-0039-1693664] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2019] [Accepted: 06/13/2019] [Indexed: 12/16/2022]
Abstract
Pathogenic variants in the TRAPPC6B gene were recently found to be associated in three consanguineous families, with microcephaly, epilepsy, and brain malformations. Here, we report on a 3.5-year-old boy, born to consanguineous Lebanese parents, who presented with developmental delay, lactic acidosis, postnatal microcephaly, and abnormal brain magnetic resonance imaging. By whole exome sequencing, a novel homozygous likely pathogenic variant in exon 1 of the TRAPPC6B gene (c.23T > A; [p.Leu8*]) was identified. A review of the clinical description and literature is discussed, pointing out the phenotypic heterogeneity associated with mutations in this gene.
Collapse
Affiliation(s)
| | - Lara El-Bazzal
- Aix Marseille University, Inserm, Marseille Medical Genetics
| | | | - Sandra Sabbagh
- Department of Pediatrics, Saint George Hospital, Beirut, Lebanon
| | | | | | - Valerie Delague
- Aix Marseille University, Inserm, Marseille Medical Genetics
| | | | - André Mégarbané
- Department of Pediatrics, Hotel-Dieu de France, Beirut, Lebanon.,Institut Jérôme Lejeune, BioJeL Biological Resource Center (CRB BioJeL), Paris, France
| |
Collapse
|