1
|
Phillips JB, Park SS, Lin CH, Cho J, Lim S, Aurora R, Kim JH, Angajala A, Park B, Stone JK, Wang B, Kahn AG, Lim STS, Kim JH, Ahn EYE, Tan M. SON is an essential RNA splicing factor promoting ErbB2 and ErbB3 expression in breast cancer. Br J Cancer 2024:10.1038/s41416-024-02853-x. [PMID: 39313574 DOI: 10.1038/s41416-024-02853-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 08/28/2024] [Accepted: 09/11/2024] [Indexed: 09/25/2024] Open
Abstract
BACKGROUND In breast cancer, ErbB receptors play a critical role, and overcoming drug resistance remains a major challenge in the clinic. However, intricate regulatory mechanisms of ErbB family genes are poorly understood. Here, we demonstrate SON as an ErbB-regulatory splicing factor and a novel therapeutic target for ErbB-positive breast cancer. METHODS SON and ErbB expression analyses using public database, patient tissue microarray, and cell lines were performed. SON knockdown assessed its impact on cell proliferation, apoptosis, kinase phosphorylation, RNA splicing, and in vivo tumour growth. RNA immunoprecipitation was performed to measure SON binding. RESULTS SON is highly expressed in ErbB2-positive breast cancer patient samples, inversely correlating with patient survival. SON knockdown induced intron retention in selective splice sites within ErbB2 and ErbB3 transcripts, impairing effective RNA splicing and reducing protein expression. SON disruption suppressed downstream kinase signalling of ErbB2/3, including the Akt, p38, and JNK pathways, with increased vulnerability in ErbB2-positive breast cancer cells compared to ErbB2-negative cells. SON silencing in ErbB2-positive breast cancer xenografts led to tumour regression in vivo. CONCLUSION We identified SON as a novel RNA splicing factor that plays a critical role in regulating ErbB2/3 expression, suggesting SON is an ideal therapeutic target in ErbB2-positive breast cancers.
Collapse
Affiliation(s)
- Joshua B Phillips
- Mitchell Cancer Institute, University of South Alabama, Mobile, AL, USA
| | - Seong-Sik Park
- Research Institute, National Cancer Center, 323 Ilsan-ro, Goyang-si, Gyeonggido, Republic of Korea
| | - Cheng-Han Lin
- Institute of Biochemistry and Molecular Biology, China Medical University, Taichung, Taiwan
| | - Juyoung Cho
- Research Institute, National Cancer Center, 323 Ilsan-ro, Goyang-si, Gyeonggido, Republic of Korea
| | - Sangbin Lim
- Mitchell Cancer Institute, University of South Alabama, Mobile, AL, USA
| | - Ritu Aurora
- Mitchell Cancer Institute, University of South Alabama, Mobile, AL, USA
| | - Jin-Hwan Kim
- Mitchell Cancer Institute, University of South Alabama, Mobile, AL, USA
| | - Anusha Angajala
- Mitchell Cancer Institute, University of South Alabama, Mobile, AL, USA
| | - Bohye Park
- Department of Pathology, Division of Molecular and Cellular Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Joshua K Stone
- Mitchell Cancer Institute, University of South Alabama, Mobile, AL, USA
| | - Bin Wang
- Department of Math and Statistics, University of South Alabama, Mobile, AL, USA
| | - Andrea G Kahn
- Department of Pathology, Division of Anatomic Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Ssang-Taek Steve Lim
- Department of Pathology, Division of Molecular and Cellular Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
- O'Neal Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Jung-Hyun Kim
- Mitchell Cancer Institute, University of South Alabama, Mobile, AL, USA.
- Research Institute, National Cancer Center, 323 Ilsan-ro, Goyang-si, Gyeonggido, Republic of Korea.
| | - Eun-Young Erin Ahn
- Department of Pathology, Division of Molecular and Cellular Pathology, University of Alabama at Birmingham, Birmingham, AL, USA.
- O'Neal Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, AL, USA.
| | - Ming Tan
- Institute of Biochemistry and Molecular Biology, China Medical University, Taichung, Taiwan.
- Cancer Biology and Precision Therapeutics Center, China Medical University, Taichung, Taiwan.
- Graduate Institute of Biomedical Sciences and Research Center for Cancer Biology, China Medical University, Taichung, Taiwan.
| |
Collapse
|
2
|
Vukadin L, Park B, Mohamed M, Li H, Elkholy A, Torrelli-Diljohn A, Kim JH, Jeong K, Murphy JM, Harvey CA, Dunlap S, Gehrs L, Lee H, Kim HG, Lee SN, Stanford D, Barrington RA, Foote JB, Sorace AG, Welner RS, Hildreth BE, Lim STS, Ahn EYE. A mouse model of ZTTK syndrome reveals indispensable SON functions in organ development and hematopoiesis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.19.567732. [PMID: 38014320 PMCID: PMC10680872 DOI: 10.1101/2023.11.19.567732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
Rare diseases are underrepresented in biomedical research, leading to insufficient awareness. Zhu-Tokita-Takenouchi-Kim (ZTTK) syndrome is a rare disease caused by genetic alterations that result in heterozygous loss-of-function of SON. While ZTTK syndrome patients suffer from numerous symptoms, the lack of model organisms hamper our understanding of both SON and this complex syndrome. Here, we developed Son haploinsufficiency (Son+/-) mice as a model of ZTTK syndrome and identified the indispensable roles of Son in organ development and hematopoiesis. Son+/- mice recapitulated clinical symptoms of ZTTK syndrome, including growth retardation, cognitive impairment, skeletal abnormalities, and kidney agenesis. Furthermore, we identified hematopoietic abnormalities in Son+/- mice, similar to those observed in human patients. Surface marker analyses and single-cell transcriptome profiling of hematopoietic stem and progenitor cells revealed that Son haploinsufficiency inclines cell fate toward the myeloid lineage but compromises lymphoid lineage development by reducing key genes required for lymphoid and B cell lineage specification. Additionally, Son haploinsufficiency causes inappropriate activation of erythroid genes and impaired erythroid maturation. These findings highlight the importance of the full gene dosage of Son in organ development and hematopoiesis. Our model serves as an invaluable research tool for this rare disease and related disorders associated with SON dysfunction.
Collapse
Affiliation(s)
- Lana Vukadin
- Department of Pathology, Division of Molecular and Cellular Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Bohye Park
- Department of Pathology, Division of Molecular and Cellular Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Mostafa Mohamed
- Department of Pathology, Division of Molecular and Cellular Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Huashi Li
- Department of Pathology, Division of Molecular and Cellular Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Amr Elkholy
- Department of Pathology, Division of Molecular and Cellular Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Alex Torrelli-Diljohn
- Department of Neurosurgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Jung-Hyun Kim
- Metastasis Branch, Division of Cancer Biology, National Cancer Center, Goyang, Gyeonggi-do, Korea
| | - Kyuho Jeong
- Department of Medicine, College of Medicine, Dongguk University, Gyeongju, Korea
| | - James M Murphy
- Department of Pathology, Division of Molecular and Cellular Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Caitlin A. Harvey
- Department of Pathology, Division of Molecular and Cellular Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Sophia Dunlap
- Department of Pathology, Division of Molecular and Cellular Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Leah Gehrs
- Department of Pathology, Division of Molecular and Cellular Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Hanna Lee
- Department of Pathology, Division of Molecular and Cellular Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Hyung-Gyoon Kim
- Department of Pathology, Division of Molecular and Cellular Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Seth N. Lee
- Department of Radiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Denise Stanford
- Department of Medicine, Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Robert A. Barrington
- Department of Microbiology and Immunology, College of Medicine, University of South Alabama, Mobile, AL, USA
| | - Jeremy B. Foote
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Anna G. Sorace
- Department of Radiology, University of Alabama at Birmingham, Birmingham, AL, USA
- O’Neal Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Robert S. Welner
- O’Neal Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, AL, USA
- Department of Medicine, Division of Hematology and Oncology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Blake E. Hildreth
- Department of Pathology, Division of Molecular and Cellular Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
- O’Neal Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Ssang-Taek Steve Lim
- Department of Pathology, Division of Molecular and Cellular Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
- O’Neal Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Eun-Young Erin Ahn
- Department of Pathology, Division of Molecular and Cellular Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
- O’Neal Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, AL, USA
| |
Collapse
|
3
|
Tang S, You J, Liu L, Ouyang H, Jiang N, Duan J, Li C, Luo Y, Zhang W, Zhan M, Liu C, Lyu G, Zhang VW, Zhao H. Expanding the mutational spectrum of ZTTK syndrome: A de novo variant with global developmental delay and malnutrition in a Chinese patient. Mol Genet Genomic Med 2023; 11:e2188. [PMID: 37488749 PMCID: PMC10422072 DOI: 10.1002/mgg3.2188] [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: 06/18/2022] [Revised: 10/23/2022] [Accepted: 02/22/2023] [Indexed: 07/26/2023] Open
Abstract
BACKGROUND Zhu-Tokita-Takenouchi-Kim (ZTTK, OMIM 617140) syndrome is a severe multisystem developmental disorder characterized by intellectual disability, developmental delay, cortical malformations, epilepsy, visual problems, musculoskeletal abnormalities, and congenital malformations. ZTTK syndrome is caused by a heterozygous pathogenic variant of the SON gene (NM_138927) at chromosome 21q22.1. The purpose of this study was to investigate the pathogenesis of a 6-month-old Chinese child who exhibited global developmental delay, muscle weakness, malnutrition, weight loss, and strabismus, brain abnormality, immunological system abnormalities. METHODS The little girl was tested for medical exome sequencing (MES) and mtDNA sequencing in trio. And, the mutation was validated by Sanger sequencing. RESULTS A novel de novo frameshift variant, c.1845_1870del26 (p.G616Sfs*61), in the SON gene was found in the proband. CONCLUSION We described a 6-month-old Chinese child with global developmental delay caused by pathogenic de novo mutation c.1845_1870del26 (p.G616Sfs*61) in the SON. Apart from a founder mutation, we reviewed the phenotypic abnormalities and genotypes in 79 individuals. The data showed that global developmental delay is accompanied by other system disorders. Our findings expanded the mutational spectrum of ZTTK syndrome and provide genetic counseling of baby with global developmental delay.
Collapse
Affiliation(s)
- Shuo Tang
- Department of Digestive System DiseasesHunan Children's HospitalChangshaChina
| | - Jieyu You
- Department of Digestive System DiseasesHunan Children's HospitalChangshaChina
| | - Li Liu
- Department of Digestive System DiseasesHunan Children's HospitalChangshaChina
| | - Hongjuan Ouyang
- Department of Digestive System DiseasesHunan Children's HospitalChangshaChina
| | - Na Jiang
- Department of Digestive System DiseasesHunan Children's HospitalChangshaChina
| | - Jiaqi Duan
- Department of Digestive System DiseasesHunan Children's HospitalChangshaChina
| | - Canlin Li
- Department of Digestive System DiseasesHunan Children's HospitalChangshaChina
| | - Yanhong Luo
- Department of Digestive System DiseasesHunan Children's HospitalChangshaChina
| | - Wenting Zhang
- Department of Digestive System DiseasesHunan Children's HospitalChangshaChina
| | - Meizheng Zhan
- Department of Digestive System DiseasesHunan Children's HospitalChangshaChina
| | - Chenxi Liu
- Department of Digestive System DiseasesHunan Children's HospitalChangshaChina
| | | | | | - Hongmei Zhao
- Department of Digestive System DiseasesHunan Children's HospitalChangshaChina
| |
Collapse
|
4
|
Langford J, Vukadin L, Carey JC, Botto LD, Velinder M, Mao R, Miller CE, Filloux F, Ahn EYE. SON-Related Zhu-Tokita-Takenouchi-Kim Syndrome With Recurrent Hemiplegic Migraine: Putative Role of PRRT2. Neurol Genet 2023; 9:e200062. [PMID: 37057295 PMCID: PMC10091367 DOI: 10.1212/nxg.0000000000200062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Accepted: 01/20/2023] [Indexed: 04/15/2023]
Abstract
Background and Objectives Zhu-Tokita-Takenouchi-Kim (ZTTK) syndrome (OMIM 617140) is a recently identified neurodevelopmental disorder caused by heterozygous loss-of-function (LoF) variants in SON. Because the SON protein functions as an RNA-splicing regulator, it has been shown that some clinical features of ZTTK syndrome can be attributed to abnormal RNA splicing. Several neurologic features have been observed in patients with ZTTK syndrome, including seizure/epilepsy and other EEG abnormalities. However, a relationship between SON LoF in ZTTK syndrome and hemiplegic migraine remains unknown. Methods We identified a patient with a pathogenic variant in SON who shows typical clinical features of ZTTK syndrome and experienced recurrent episodes of hemiplegic migraine. To define clinical features, brain MRI and EEG during and after episodes of hemiplegic migraine were characterized. To identify molecular mechanisms for this clinical presentation, we investigated the impact of small interfering RNA (siRNA)-mediated SON knockdown on mRNA expression of the CACNA1A, ATP1A2, SCN1A, and PRRT2 genes, known to be associated with hemiplegic migraine, by quantitative RT-PCR. Pre-mRNA splicing of PRRT2 on SON knockdown was further examined by RT-PCR using primers targeting specific exons. Results Recurrent episodes of hemiplegic migraine in our patient typically followed modest closed head injuries, and recurrent seizures occurred during the most severe of these episodes. Transient hemispheric cortical interstitial edema and asymmetric EEG slowing were identified during episodes. Our siRNA experiments revealed that SON knockdown significantly reduces PRRT2 mRNA levels in U87MG and SH-SY5Y cell lines, although a reduction in CACNA1A, ATP1A2, and SCN1A mRNA expression was not observed. We further identified that SON knockdown leads to failure in intron 2 removal from PRRT2 pre-mRNA, resulting in a premature termination codon that blocks the generation of functionally intact full-length PRRT2. Discussion This report identifies recurrent hemiplegic migraine as a novel clinical manifestation of ZTTK syndrome, further characterizes this clinical feature, and provides evidence for downregulation of PRRT2 caused by SON LoF as a mechanism causing hemiplegic migraine. Examination of the SON gene may be indicated in individuals with recurrent hemiplegic migraine.
Collapse
Affiliation(s)
- Jordan Langford
- University of Utah School of Medicine, University of Utah (J.L.), Salt Lake City, UT; Department of Pathology, Division of Molecular and Cellular Pathology (L.V., E.-Y.E.A.), University of Alabama at Birmingham, Birmingham, AL; Division of Medical Genetics (L.D.B.), Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT; Utah Center for Genetic Discovery, Eccles Institute of Human Genetics (M.V.), University of Utah School of Medicine; Department of Pathology (R.M.), University of Utah School of Medicine, Salt Lake City, UT; Division of Integrated Oncology and Genetics (R.M., C.E.M.), Molecular Genetics, ARUP Laboratories, Salt Lake City, UT; Division of Pediatric Neurology (F.F.), University of Utah School of Medicine, Salt Lake City, UT; and O'Neal Comprehensive Cancer Center (E.-Y.E.A.), University of Alabama at Birmingham, Birmingham, AL
| | - Lana Vukadin
- University of Utah School of Medicine, University of Utah (J.L.), Salt Lake City, UT; Department of Pathology, Division of Molecular and Cellular Pathology (L.V., E.-Y.E.A.), University of Alabama at Birmingham, Birmingham, AL; Division of Medical Genetics (L.D.B.), Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT; Utah Center for Genetic Discovery, Eccles Institute of Human Genetics (M.V.), University of Utah School of Medicine; Department of Pathology (R.M.), University of Utah School of Medicine, Salt Lake City, UT; Division of Integrated Oncology and Genetics (R.M., C.E.M.), Molecular Genetics, ARUP Laboratories, Salt Lake City, UT; Division of Pediatric Neurology (F.F.), University of Utah School of Medicine, Salt Lake City, UT; and O'Neal Comprehensive Cancer Center (E.-Y.E.A.), University of Alabama at Birmingham, Birmingham, AL
| | - John C Carey
- University of Utah School of Medicine, University of Utah (J.L.), Salt Lake City, UT; Department of Pathology, Division of Molecular and Cellular Pathology (L.V., E.-Y.E.A.), University of Alabama at Birmingham, Birmingham, AL; Division of Medical Genetics (L.D.B.), Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT; Utah Center for Genetic Discovery, Eccles Institute of Human Genetics (M.V.), University of Utah School of Medicine; Department of Pathology (R.M.), University of Utah School of Medicine, Salt Lake City, UT; Division of Integrated Oncology and Genetics (R.M., C.E.M.), Molecular Genetics, ARUP Laboratories, Salt Lake City, UT; Division of Pediatric Neurology (F.F.), University of Utah School of Medicine, Salt Lake City, UT; and O'Neal Comprehensive Cancer Center (E.-Y.E.A.), University of Alabama at Birmingham, Birmingham, AL
| | - Lorenzo D Botto
- University of Utah School of Medicine, University of Utah (J.L.), Salt Lake City, UT; Department of Pathology, Division of Molecular and Cellular Pathology (L.V., E.-Y.E.A.), University of Alabama at Birmingham, Birmingham, AL; Division of Medical Genetics (L.D.B.), Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT; Utah Center for Genetic Discovery, Eccles Institute of Human Genetics (M.V.), University of Utah School of Medicine; Department of Pathology (R.M.), University of Utah School of Medicine, Salt Lake City, UT; Division of Integrated Oncology and Genetics (R.M., C.E.M.), Molecular Genetics, ARUP Laboratories, Salt Lake City, UT; Division of Pediatric Neurology (F.F.), University of Utah School of Medicine, Salt Lake City, UT; and O'Neal Comprehensive Cancer Center (E.-Y.E.A.), University of Alabama at Birmingham, Birmingham, AL
| | - Matt Velinder
- University of Utah School of Medicine, University of Utah (J.L.), Salt Lake City, UT; Department of Pathology, Division of Molecular and Cellular Pathology (L.V., E.-Y.E.A.), University of Alabama at Birmingham, Birmingham, AL; Division of Medical Genetics (L.D.B.), Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT; Utah Center for Genetic Discovery, Eccles Institute of Human Genetics (M.V.), University of Utah School of Medicine; Department of Pathology (R.M.), University of Utah School of Medicine, Salt Lake City, UT; Division of Integrated Oncology and Genetics (R.M., C.E.M.), Molecular Genetics, ARUP Laboratories, Salt Lake City, UT; Division of Pediatric Neurology (F.F.), University of Utah School of Medicine, Salt Lake City, UT; and O'Neal Comprehensive Cancer Center (E.-Y.E.A.), University of Alabama at Birmingham, Birmingham, AL
| | - Rong Mao
- University of Utah School of Medicine, University of Utah (J.L.), Salt Lake City, UT; Department of Pathology, Division of Molecular and Cellular Pathology (L.V., E.-Y.E.A.), University of Alabama at Birmingham, Birmingham, AL; Division of Medical Genetics (L.D.B.), Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT; Utah Center for Genetic Discovery, Eccles Institute of Human Genetics (M.V.), University of Utah School of Medicine; Department of Pathology (R.M.), University of Utah School of Medicine, Salt Lake City, UT; Division of Integrated Oncology and Genetics (R.M., C.E.M.), Molecular Genetics, ARUP Laboratories, Salt Lake City, UT; Division of Pediatric Neurology (F.F.), University of Utah School of Medicine, Salt Lake City, UT; and O'Neal Comprehensive Cancer Center (E.-Y.E.A.), University of Alabama at Birmingham, Birmingham, AL
| | - Christine E Miller
- University of Utah School of Medicine, University of Utah (J.L.), Salt Lake City, UT; Department of Pathology, Division of Molecular and Cellular Pathology (L.V., E.-Y.E.A.), University of Alabama at Birmingham, Birmingham, AL; Division of Medical Genetics (L.D.B.), Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT; Utah Center for Genetic Discovery, Eccles Institute of Human Genetics (M.V.), University of Utah School of Medicine; Department of Pathology (R.M.), University of Utah School of Medicine, Salt Lake City, UT; Division of Integrated Oncology and Genetics (R.M., C.E.M.), Molecular Genetics, ARUP Laboratories, Salt Lake City, UT; Division of Pediatric Neurology (F.F.), University of Utah School of Medicine, Salt Lake City, UT; and O'Neal Comprehensive Cancer Center (E.-Y.E.A.), University of Alabama at Birmingham, Birmingham, AL
| | - Francis Filloux
- University of Utah School of Medicine, University of Utah (J.L.), Salt Lake City, UT; Department of Pathology, Division of Molecular and Cellular Pathology (L.V., E.-Y.E.A.), University of Alabama at Birmingham, Birmingham, AL; Division of Medical Genetics (L.D.B.), Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT; Utah Center for Genetic Discovery, Eccles Institute of Human Genetics (M.V.), University of Utah School of Medicine; Department of Pathology (R.M.), University of Utah School of Medicine, Salt Lake City, UT; Division of Integrated Oncology and Genetics (R.M., C.E.M.), Molecular Genetics, ARUP Laboratories, Salt Lake City, UT; Division of Pediatric Neurology (F.F.), University of Utah School of Medicine, Salt Lake City, UT; and O'Neal Comprehensive Cancer Center (E.-Y.E.A.), University of Alabama at Birmingham, Birmingham, AL
| | - Eun-Young Erin Ahn
- University of Utah School of Medicine, University of Utah (J.L.), Salt Lake City, UT; Department of Pathology, Division of Molecular and Cellular Pathology (L.V., E.-Y.E.A.), University of Alabama at Birmingham, Birmingham, AL; Division of Medical Genetics (L.D.B.), Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT; Utah Center for Genetic Discovery, Eccles Institute of Human Genetics (M.V.), University of Utah School of Medicine; Department of Pathology (R.M.), University of Utah School of Medicine, Salt Lake City, UT; Division of Integrated Oncology and Genetics (R.M., C.E.M.), Molecular Genetics, ARUP Laboratories, Salt Lake City, UT; Division of Pediatric Neurology (F.F.), University of Utah School of Medicine, Salt Lake City, UT; and O'Neal Comprehensive Cancer Center (E.-Y.E.A.), University of Alabama at Birmingham, Birmingham, AL
| |
Collapse
|
5
|
The Expanding Phenotype of ZTTK Syndrome Due to the Heterozygous Variant of SON Gene Focusing on Liver Involvement: Patient Report and Literature Review. Genes (Basel) 2023; 14:genes14030739. [PMID: 36981010 PMCID: PMC10048019 DOI: 10.3390/genes14030739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2023] [Revised: 03/08/2023] [Accepted: 03/13/2023] [Indexed: 03/19/2023] Open
Abstract
Zhu–Tokita–Takenouchi–Kim (ZTTK) syndrome, an intellectual disability syndrome first described in 2016, is caused by heterozygous loss-of-function variants in SON. Haploinsufficiency in SON may affect multiple genes, including those involved in the development and metabolism of multiple organs. Considering the broad spectrum of SON functions, it is to be expected that pathogenic variants in this gene can cause a wide spectrum of clinical symptoms. We present an additional ZTTK syndrome case due to a de novo heterozygous variant in the SON gene (c.5751_5754delAGTT). The clinical manifestations of our patient were similar to those present in previously reported cases; however, the diagnosis of ZTTK syndrome was delayed for a long time and was carried out during the diagnostic work-up of significant chronic liver disease (CLD). CLD has not yet been reported in any series; therefore, our report provides new information on this rare condition and suggests the expansion of the ZTTK syndrome phenotype, including possible liver involvement. Correspondingly, we recommend screening patients with SON variants specifically for liver involvement from the first years of life. Once the CLD has been diagnosed, an appropriate follow-up is mandatory, especially considering the role of SON as an emerging player in cancer development. Further studies are needed to investigate the role of SON haploinsufficiency as a downregulator of essential genes, thus potentially impairing the normal development and/or functions of multiple organs.
Collapse
|
6
|
Pavone P, Saia F, Pappalardo X, Barbagallo M, Prato A, Rizzo R. Novel malformations: Chiari type 1 and hydrocephalus in Zhu-Tokita-Takenouchi-Kim syndrome and novel SON variants. Clin Case Rep 2022; 10:e6529. [PMID: 36540882 PMCID: PMC9755635 DOI: 10.1002/ccr3.6529] [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: 07/09/2022] [Revised: 10/13/2022] [Accepted: 10/15/2022] [Indexed: 12/23/2022] Open
Abstract
Zhu-Tokita-Tachenouchi-Kim syndrome (ZTTK) is a recently recognized malformation syndrome presenting with craniofacial dysmorphism, developmental delay/intellectual disability, seizures, anomalies involving brain white matter, and other body-organs. In humans, the disorder is linked to the loss-of-function variants in the SON gene (MIM# 617140). Herewith, a new case of this syndrome is reported in a 2-year-old Caucasian child who presented the classical clinical features of the ZTTK syndrome in association with hydrocephalus and Chiari malformations type 1 an anomaly previously unreported. Exome analysis showed a de novo heterozygous variant in SON gene. Literature review of similar cases is reported.
Collapse
Affiliation(s)
- Piero Pavone
- Unit of Clinical Pediatrics, AOU "Policlinico", PO "G. Rodolico"University of CataniaCataniaItaly
| | - Federica Saia
- Child and Adolescent Neurology and Psichiatry, Department of Clinical and Experimental MedicineCatania UniversityCataniaItaly
| | - Xena Pappalardo
- Unit of Catania, Institute for Biomedical Research and InnovationNational Council of ResearchCataniaItaly
| | - Massimo Barbagallo
- Unit of Pediatrics and Pediatrics EmergencyHospital "G. Garibaldi"CataniaItaly
| | - Adriana Prato
- Child and Adolescent Neurology and Psichiatry, Department of Clinical and Experimental MedicineCatania UniversityCataniaItaly
- Department of Cognitive Sciences, Psychology, Education and Cultural StudiesUniversity of MessinaMessinaItaly
| | - Renata Rizzo
- Child and Adolescent Neurology and Psichiatry, Department of Clinical and Experimental MedicineCatania UniversityCataniaItaly
| |
Collapse
|
7
|
Halliday BJ, Baynam G, Ewans L, Greenhalgh L, Leventer RJ, Pilz DT, Sachdev R, Scheffer IE, Markie DM, McGillivray G, Robertson SP, Mandelstam S. Distinctive Brain Malformations in Zhu-Tokita-Takenouchi-Kim Syndrome. AJNR Am J Neuroradiol 2022; 43:1660-1666. [PMID: 36229163 PMCID: PMC9731255 DOI: 10.3174/ajnr.a7663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Accepted: 08/08/2022] [Indexed: 02/01/2023]
Abstract
BACKGROUND AND PURPOSE Zhu-Tokita-Takenouchi-Kim syndrome is a severe multisystem malformation disorder characterized by developmental delay and a diverse array of congenital abnormalities. However, these currently identified phenotypic components provide limited guidance in diagnostic situations, due to both the nonspecificity and variability of these features. Here we report a case series of 7 individuals with a molecular diagnosis of Zhu-Tokita-Takenouchi-Kim syndrome, 5 ascertained by their presentation with the neuronal migration disorder, periventricular nodular heterotopia. MATERIALS AND METHODS Individuals with a molecular diagnosis of Zhu-Tokita-Takenouchi-Kim syndrome were recruited from 2 sources, a high-throughput sequencing study of individuals with periventricular nodular heterotopia or from clinical diagnostic sequencing studies. We analyzed available brain MR images of recruited individuals to characterize periventricular nodular heterotopia distribution and to identify the presence of any additional brain abnormalities. RESULTS Pathogenic variants in SON, causative of Zhu-Tokita-Takenouchi-Kim syndrome, were identified in 7 individuals. Brain MR images from these individuals were re-analyzed. A characteristic set of imaging anomalies in addition to periventricular nodular heterotopia was identified, including the elongation of the pituitary stalk, cerebellar enlargement with an abnormally shaped posterior fossa, rounding of the caudate nuclei, hippocampal malformations, and cortical anomalies including polymicrogyria or dysgyria. CONCLUSIONS The recurrent neuroradiologic changes identified here represent an opportunity to guide diagnostic formulation of Zhu-Tokita-Takenouchi-Kim syndrome on the basis of brain MR imaging evaluation.
Collapse
Affiliation(s)
- B J Halliday
- From the Departments of Women's and Children's Health (B.J.H., S.P.R.)
| | - G Baynam
- Western Australian Register of Developmental Anomalies and Genetic Services of Western Australia (G.B.), Undiagnosed Diseases Program, King Edward Memorial Hospital, Perth, Australia
| | - L Ewans
- Centre for Population Genomics (L.E.), Garvan Institute of Medical Research, Sydney, Australia
- Centre for Clinical Genetics (L.E., R.S.), Sydney Children's Hospital, Sydney, Australia
| | - L Greenhalgh
- Liverpool Centre for Genomic Medicine (L.G.), Liverpool Women's Hospital, Liverpool, England
| | - R J Leventer
- Murdoch Children's Research Institute (R.J.L., I.E.S., G.M., S.M.), Melbourne, Australia
- Department of Paediatrics (R.J.L., I.E.S., S.M.), Epilepsy Research Centre
- Departments of Neurology (R.J.L., I.E.S.)
| | - D T Pilz
- West of Scotland Genetics Service (D.T.P.), Queen Elizabeth University Hospital, Glasgow, UK
| | - R Sachdev
- Centre for Clinical Genetics (L.E., R.S.), Sydney Children's Hospital, Sydney, Australia
| | - I E Scheffer
- Murdoch Children's Research Institute (R.J.L., I.E.S., G.M., S.M.), Melbourne, Australia
- Department of Paediatrics (R.J.L., I.E.S., S.M.), Epilepsy Research Centre
- Austin Health (I.E.S.)
- Florey Institute (I.E.S.), University of Melbourne, Melbourne, Australia
- Departments of Neurology (R.J.L., I.E.S.)
| | - D M Markie
- Pathology (D.M.M.), OtagoMedical School, University of Otago, Dunedin, New Zealand
| | - G McGillivray
- Murdoch Children's Research Institute (R.J.L., I.E.S., G.M., S.M.), Melbourne, Australia
- Victorian Clinical Genetics Services (G.M.), Murdoch Children's Research Institute, Melbourne, Australia
| | - S P Robertson
- From the Departments of Women's and Children's Health (B.J.H., S.P.R.)
| | - S Mandelstam
- Murdoch Children's Research Institute (R.J.L., I.E.S., G.M., S.M.), Melbourne, Australia
- Department of Paediatrics (R.J.L., I.E.S., S.M.), Epilepsy Research Centre
- Radiology (S.M.), Royal Children's Hospital, Melbourne, Australia
| |
Collapse
|
8
|
Establishing the phenotypic spectrum of ZTTK syndrome by analysis of 52 individuals with variants in SON. Eur J Hum Genet 2022; 30:271-281. [PMID: 34521999 PMCID: PMC8904542 DOI: 10.1038/s41431-021-00960-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 07/16/2021] [Accepted: 08/26/2021] [Indexed: 12/22/2022] Open
Abstract
Zhu-Tokita-Takenouchi-Kim (ZTTK) syndrome, an intellectual disability syndrome first described in 2016, is caused by heterozygous loss-of-function variants in SON. Its encoded protein promotes pre-mRNA splicing of many genes essential for development. Whereas individual phenotypic traits have previously been linked to erroneous splicing of SON target genes, the phenotypic spectrum and the pathogenicity of missense variants have not been further evaluated. We present the phenotypic abnormalities in 52 individuals, including 17 individuals who have not been reported before. In total, loss-of-function variants were detected in 49 individuals (de novo in 47, inheritance unknown in 2), and in 3, a missense variant was observed (2 de novo, 1 inheritance unknown). Phenotypic abnormalities, systematically collected and analyzed in Human Phenotype Ontology, were found in all organ systems. Significant inter-individual phenotypic variability was observed, even in individuals with the same recurrent variant (n = 13). SON haploinsufficiency was previously shown to lead to downregulation of downstream genes, contributing to specific phenotypic features. Similar functional analysis for one missense variant, however, suggests a different mechanism than for heterozygous loss-of-function. Although small in numbers and while pathogenicity of these variants is not certain, these data allow for speculation whether de novo missense variants cause ZTTK syndrome via another mechanism, or a separate overlapping syndrome. In conclusion, heterozygous loss-of-function variants in SON define a recognizable syndrome, ZTTK, associated with a broad, severe phenotypic spectrum, characterized by a large inter-individual variability. These observations provide essential information for affected individuals, parents, and healthcare professionals to ensure appropriate clinical management.
Collapse
|
9
|
A genotype-first analysis in a cohort of Mullerian anomaly. J Hum Genet 2022; 67:347-352. [PMID: 35022528 DOI: 10.1038/s10038-021-00996-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 11/15/2021] [Accepted: 11/16/2021] [Indexed: 11/08/2022]
Abstract
Müllerian anomaly (M.A.) is a group of congenital anatomic abnormalities caused by aberrations of the development process of the Müllerian duct. M.A. can either be isolated or be involved in Mendelian syndromes, such as Dandy-Walker syndrome, Holt-Oram syndrome and Bardet-Biedl syndrome, which are often associated with both uterus and kidney malformations. In this study, we applied a genotype-first approach to analyze the whole-exome sequencing data of 492 patients with M.A. Six potential pathogenic variants were found in five genes previously related to female urogenital deformities (PKD1, SON, SALL1, BMPR1B, ITGA8), which are partially overlapping with our patients' phenotypes. We further identified eight incidental findings in seven genes related to Mendelian syndromes without known association with reproductive anomalies (TEK, COL11A1, ANKRD11, LEMD3, DLG5, SPTB, BMP2), which represent potential phenotype expansions of these genes.
Collapse
|
10
|
Kushary ST, Revah-Politi A, Barua S, Ganapathi M, Accogli A, Aggarwal V, Brunetti-Pierri N, Cappuccio G, Capra V, Fagerberg CR, Gazdagh G, Guzman E, Hadonou M, Harrison V, Havelund K, Iancu D, Kraus A, Lippa NC, Mansukhani M, McBrian D, McEntagart M, Pacio-Míguez M, Palomares-Bralo M, Pottinger C, Ruivenkamp CAL, Sacco O, Santen GWE, Santos-Simarro F, Scala M, Short J, Sørensen KP, Woods CG, Anyane Yeboa K. ZTTK syndrome: Clinical and molecular findings of 15 cases and a review of the literature. Am J Med Genet A 2021; 185:3740-3753. [PMID: 34331327 DOI: 10.1002/ajmg.a.62445] [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: 03/01/2021] [Revised: 05/21/2021] [Accepted: 07/09/2021] [Indexed: 11/10/2022]
Abstract
Zhu-Tokita-Takenouchi-Kim (ZTTK) syndrome is caused by de novo loss-of-function variants in the SON gene (MIM #617140). This multisystemic disorder is characterized by intellectual disability, seizures, abnormal brain imaging, variable dysmorphic features, and various congenital anomalies. The wide application and increasing accessibility of whole exome sequencing (WES) has helped to identify new cases of ZTTK syndrome over the last few years. To date, there have been approximately 45 cases reported in the literature. Here, we describe 15 additional individuals with variants in the SON gene, including those with missense variants bringing the total number of known cases to 60. We have reviewed the clinical and molecular data of these new cases and all previously reported cases to further delineate the most common as well as emerging clinical findings related to this syndrome. Furthermore, we aim to delineate any genotype-phenotype correlations specifically for a recurring pathogenic four base pair deletion (c.5753_5756del) along with discussing the impact of missense variants seen in the SON gene.
Collapse
Affiliation(s)
- Sulagna Tina Kushary
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, New York, USA
| | - Anya Revah-Politi
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, New York, USA.,Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, New York, USA
| | - Subit Barua
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, New York, USA
| | - Mythily Ganapathi
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, New York, USA
| | | | - Vimla Aggarwal
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, New York, USA
| | - Nicola Brunetti-Pierri
- Telethon Institute of Genetics and Medicine, Pozzuoli, Italy.,Department of Translational Medicine, Federico II University of Naples, Naples, Italy
| | - Gerarda Cappuccio
- Telethon Institute of Genetics and Medicine, Pozzuoli, Italy.,Department of Translational Medicine, Federico II University of Naples, Naples, Italy
| | - Valeria Capra
- IRCCS 'G. Gaslini' Children's Hospital, Genoa, Italy
| | | | - Gabriella Gazdagh
- West of Scotland Centre for Genomic Medicine, Laboratory Medicine Building, Queen Elizabeth University Hospital, Glasgow, UK
| | - Edwin Guzman
- Division of Clinical Genetics, Department of Pediatrics, Columbia University Irving Medical Center, New York, New York, USA
| | - Medard Hadonou
- St. George's Genomics Service, St. George's University Hospitals NHS FT, London, UK
| | | | - Kathrine Havelund
- HC Andersen Children's Hospital, Odense University Hospital, Odense, Denmark
| | | | - Alison Kraus
- Department of Clinical Genetics, Odense University Hospital, Odense, Denmark
| | - Natalie C Lippa
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, New York, USA
| | - Mahesh Mansukhani
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, New York, USA
| | - Danielle McBrian
- Department of Neurology, Columbia University Irving Medical Center, New York, New York, USA
| | - Meriel McEntagart
- Department of Medical Genetics, St. George's University Hospital NHS FT, London, UK
| | - Marta Pacio-Míguez
- Instituto de Genética Médica y Molecular (INGEMM), Hospital Universitario La Paz, IdiPAZ, CIBERER, ISCIII, Madrid, Spain
| | - María Palomares-Bralo
- Instituto de Genética Médica y Molecular (INGEMM), Hospital Universitario La Paz, IdiPAZ, CIBERER, ISCIII, Madrid, Spain
| | - Carrie Pottinger
- Department of Clinical Genetics, All Wales Genomic Medicine Service, Maelor Hospital, Wrexham, UK
| | - Claudia A L Ruivenkamp
- Department of Clinical Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | | | - Gijs W E Santen
- Department of Clinical Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Fernando Santos-Simarro
- Instituto de Genética Médica y Molecular (INGEMM), Hospital Universitario La Paz, IdiPAZ, CIBERER, ISCIII, Madrid, Spain
| | | | - John Short
- St. George's Genomics Service, St. George's University Hospitals NHS FT, London, UK
| | - Kristina P Sørensen
- HC Andersen Children's Hospital, Odense University Hospital, Odense, Denmark
| | - Christopher G Woods
- Cambridge Institute for Medical Research, University of Cambridge, Addenbrooke's Hospital, Cambridge, UK
| | -
- Wellcome Trust Sanger Institute, Cambridge, UK
| | -
- Telethon Institute of Genetics and Medicine, Pozzuoli, Italy
| | - Kwame Anyane Yeboa
- Division of Clinical Genetics, Department of Pediatrics, Columbia University Irving Medical Center, New York, New York, USA
| |
Collapse
|
11
|
Belmonte RL, Engbretson IL, Kim JH, Cajias I, Ahn EYE, Stachura DL. son is necessary for proper vertebrate blood development. PLoS One 2021; 16:e0247489. [PMID: 33630943 PMCID: PMC7906411 DOI: 10.1371/journal.pone.0247489] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 02/08/2021] [Indexed: 12/15/2022] Open
Abstract
The gene SON is on human chromosome 21 (21q22.11) and is thought to be associated with hematopoietic disorders that accompany Down syndrome. Additionally, SON is an RNA splicing factor that plays a role in the transcription of leukemia-associated genes. Previously, we showed that mutations in SON cause malformations in human and zebrafish spines and brains during early embryonic development. To examine the role of SON in normal hematopoiesis, we reduced expression of the zebrafish homolog of SON in zebrafish at the single-cell developmental stage with specific morpholinos. In addition to the brain and spinal malformations we also observed abnormal blood cell levels upon son knockdown. We then investigated how blood production was altered when levels of son were reduced. Decreased levels of son resulted in lower amounts of red blood cells when visualized with lcr:GFP transgenic fish. There were also reduced thrombocytes seen with cd41:GFP fish, and myeloid cells when mpx:GFP fish were examined. We also observed a significant decrease in the quantity of T cells, visualized with lck:GFP fish. However, when we examined their hematopoietic stem and progenitor cells (HSPCs), we saw no difference in colony-forming capability. These studies indicate that son is essential for the proper differentiation of the innate and adaptive immune system, and further investigation determining the molecular pathways involved during blood development should elucidate important information about vertebrate HSPC generation, proliferation, and differentiation.
Collapse
Affiliation(s)
- Rebecca L. Belmonte
- Department of Biological Sciences, California State University Chico, Chico, California, United States of America
| | - Isabella L. Engbretson
- Department of Biological Sciences, California State University Chico, Chico, California, United States of America
| | - Jung-Hyun Kim
- Mitchell Cancer Institute, University of South Alabama, Mobile, Alabama, United States of America
| | - Illiana Cajias
- Department of Biological Sciences, California State University Chico, Chico, California, United States of America
| | - Eun-Young Erin Ahn
- Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
- O’Neal Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - David L. Stachura
- Department of Biological Sciences, California State University Chico, Chico, California, United States of America
- * E-mail:
| |
Collapse
|
12
|
Dinh K, Mark PR. Lethal renal anomalies in a fetus with 21q22.11-q22.12 deletion. Am J Med Genet A 2020; 182:3060-3063. [PMID: 32946178 DOI: 10.1002/ajmg.a.61868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 07/09/2020] [Accepted: 08/25/2020] [Indexed: 11/08/2022]
Affiliation(s)
- Kathleen Dinh
- Michigan State University College of Human Medicine, Grand Rapids, Michigan, USA
| | - Paul R Mark
- Division of Medical Genetics, Spectrum Health, Grand Rapids, Michigan, USA
| |
Collapse
|
13
|
Slezak R, Smigiel R, Rydzanicz M, Pollak A, Kosinska J, Stawinski P, Malgorzata Sasiadek M, Ploski R. Phenotypic expansion in Zhu-Tokita-Takenouchi-Kim syndrome caused by de novo variants in the SON gene. Mol Genet Genomic Med 2020; 8:e1432. [PMID: 32705777 PMCID: PMC7549597 DOI: 10.1002/mgg3.1432] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 07/02/2020] [Accepted: 07/10/2020] [Indexed: 12/16/2022] Open
Abstract
Background The genetic etiology of intellectual and psychomotor disability without a defined spectrum of dysmorphic features is usually monogenic. As no diagnostic criteria for such diseases are established, the clinical diagnosis becomes to be a challenge. The object of our paper is to present two patients with non‐specific clinical symptoms for whom whole‐exome‐sequencing identified the new SON mutations and thus allowed for establishing the diagnosis of Zhu‐Tokita‐Takenouchi‐Kim (ZTTK) syndrome. In both patients, the same symptoms including hypotonia, developmental and speech delay, feeding difficulties as well as frequent infections of the respiratory tract and internal ear were observed. However, both cases presented also with exceptional symptoms such as in case 1 ventriculomegaly and asymmetry of ventricles, hypoplastic left heart syndrome (HLHS), intellectual disability, intestinal malrotation, gastroparesis, and duodenal atresia and in the case 2 febrile seizures and reduced IgA levels. We will be presenting the patients and comparing them to 30 previously described cases. Methods Whole‐exome sequencing (WES) was performed on the probands’ DNA and paired‐end sequenced (2x100 bp) on HiSeq 1500. Variants considered as disease‐causing were validated in the proband and studied in all available family members by amplicon deep sequencing performed using Nextera XT Kit and sequenced on HiSeq 1500. Results We have identified two new variants in SON gene. In case 1 it has been a heterozygous frameshift variant p.(Ala1340GlnfsTer26), while in case 2 it has been a heterozygous frameshift variant, p.(Asp1640GlyfsTer7). Both variants are described for the first time and up to now, are not mentioned in any database. Conclusion As there are no precise criteria established for the clinical diagnosis of ZTTK, an identification of SON gene mutation by whole‐exome‐sequencing is the best method that allows for a diagnosis of this syndrome.
Collapse
Affiliation(s)
- Ryszard Slezak
- Department of Genetics, Wroclaw Medical University, Wroclaw, Poland
| | - Robert Smigiel
- Department of Pediatrics and Rare Disorders, Wroclaw Medical University, Wroclaw, Poland
| | | | - Agnieszka Pollak
- Department of Medical Genetics, Medical University of Warsaw, Warsaw, Poland
| | - Joanna Kosinska
- Department of Medical Genetics, Medical University of Warsaw, Warsaw, Poland
| | - Piotr Stawinski
- Department of Medical Genetics, Medical University of Warsaw, Warsaw, Poland
| | | | - Rafal Ploski
- Department of Medical Genetics, Medical University of Warsaw, Warsaw, Poland
| |
Collapse
|
14
|
Ueda M, Matsuki T, Fukada M, Eda S, Toya A, Iio A, Tabata H, Nakayama A. Knockdown of Son, a mouse homologue of the ZTTK syndrome gene, causes neuronal migration defects and dendritic spine abnormalities. Mol Brain 2020; 13:80. [PMID: 32448361 PMCID: PMC7245844 DOI: 10.1186/s13041-020-00622-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 05/12/2020] [Indexed: 01/08/2023] Open
Abstract
Zhu-Tokita-Takenouchi-Kim (ZTTK) syndrome, a rare congenital anomaly syndrome characterized by intellectual disability, brain malformation, facial dysmorphism, musculoskeletal abnormalities, and some visceral malformations is caused by de novo heterozygous mutations of the SON gene. The nuclear protein SON is involved in gene transcription and RNA splicing; however, the roles of SON in neural development remain undetermined. We investigated the effects of Son knockdown on neural development in mice and found that Son knockdown in neural progenitors resulted in defective migration during corticogenesis and reduced spine density on mature cortical neurons. The induction of human wild-type SON expression rescued these neural abnormalities, confirming that the abnormalities were caused by SON insufficiency. We also applied truncated SON proteins encoded by disease-associated mutant SON genes for rescue experiments and found that a truncated SON protein encoded by the most prevalent SON mutant found in ZTTK syndrome rescued the neural abnormalities while another much shorter mutant SON protein did not. These data indicate that SON insufficiency causes neuronal migration defects and dendritic spine abnormalities, which seem neuropathological bases of the neural symptoms of ZTTK syndrome. In addition, the results support that the neural abnormalities in ZTTK syndrome are caused by SON haploinsufficiency independent of the types of mutation that results in functional or dysfunctional proteins.
Collapse
Affiliation(s)
- Masashi Ueda
- Department of Cellular Pathology, Institute for Developmental Research, Aichi Developmental Disability Center, Kasugai, Aichi, 4800392, Japan
| | - Tohru Matsuki
- Department of Cellular Pathology, Institute for Developmental Research, Aichi Developmental Disability Center, Kasugai, Aichi, 4800392, Japan
| | - Masahide Fukada
- Department of Cellular Pathology, Institute for Developmental Research, Aichi Developmental Disability Center, Kasugai, Aichi, 4800392, Japan
| | - Shima Eda
- Department of Cellular Pathology, Institute for Developmental Research, Aichi Developmental Disability Center, Kasugai, Aichi, 4800392, Japan
| | - Akie Toya
- Department of Cellular Pathology, Institute for Developmental Research, Aichi Developmental Disability Center, Kasugai, Aichi, 4800392, Japan.,Department of Neurobiochemistry, Nagoya University School of Medicine, Nagoya, Aichi, 4668560, Japan
| | - Akio Iio
- Department of Cellular Pathology, Institute for Developmental Research, Aichi Developmental Disability Center, Kasugai, Aichi, 4800392, Japan.,Biogate Co. Ltd., 331-1 Ohmori, Yamagata, Gifu, 5012123, Japan
| | - Hidenori Tabata
- Department of Molecular Neurobiology, Institute for Developmental Research, Aichi Developmental Disability Center, Kasugai, Aichi, 4800392, Japan
| | - Atsuo Nakayama
- Department of Cellular Pathology, Institute for Developmental Research, Aichi Developmental Disability Center, Kasugai, Aichi, 4800392, Japan. .,Department of Neurobiochemistry, Nagoya University School of Medicine, Nagoya, Aichi, 4668560, Japan.
| |
Collapse
|
15
|
Tan Y, Duan L, Yang K, Liu Q, Wang J, Dong Z, Li Z, He Y, Yan Y, Lin L. A novel frameshift variant in SON causes Zhu-Tokita-Takenouchi-Kim Syndrome. J Clin Lab Anal 2020; 34:e23326. [PMID: 32291808 PMCID: PMC7439338 DOI: 10.1002/jcla.23326] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Revised: 03/08/2020] [Accepted: 03/14/2020] [Indexed: 12/16/2022] Open
Abstract
Background Zhu‐Tokita‐Takenouchi‐Kim syndrome is a severe multisystem developmental disorder characterized by intellectual disability, developmental delay, malformations of the cerebral cortex, epilepsy, vision problems, musculoskeletal abnormalities, and congenital malformations. This syndrome is caused by heterozygous pathogenic variants in the SON gene at chromosome 21q22.1. Objectives The aim of this study was to investigate the pathogenesis of a 4‐year‐old Chinese child who displayed severe intellectual disability, delayed psychomotor development, and facial dysmorphism. Methods A sequential detection including chromosome karyotyping, chromosome microarray analysis (CMA), and whole‐exome sequencing (WES) was performed on this child. The familial verification of WES result was conducted by Sanger sequencing. Results A de novo frameshift variant SON: c.5230delC (p.Arg1744ValfsTer29) was identified in the proband. The identical variant was not found in his family members. The frequencies of this variant in gnomAD/gnomAD_EAS databases were both none. Conclusions This study substantiates that SON: c.5230delC (p.Arg1744ValfsTer29) is a pathogenic variant of Zhu‐Tokita‐Takenouchi‐Kim syndrome and it is the first time to report Zhu‐Tokita‐Takenouchi‐Kim syndrome in China.
Collapse
Affiliation(s)
- Ya Tan
- Department of Obstetrics and Gynecology, Peking University International Hospital, Beijing, China
| | - Ling Duan
- Mianyang Maternity and Child Health Care Hospital, Sichuan, China
| | - Kai Yang
- Department of Obstetrics and Gynecology, Peking University International Hospital, Beijing, China
| | - Qian Liu
- Department of Neurological Rehabilitation, Gansu Provincial Hospital, Gansu, China
| | - Jing Wang
- Department of Obstetrics and Gynecology, Peking University International Hospital, Beijing, China
| | - Zhe Dong
- Department of Obstetrics and Gynecology, Peking University International Hospital, Beijing, China
| | - Zhi Li
- Department of Obstetrics and Gynecology, Peking University International Hospital, Beijing, China
| | - Yiwen He
- Department of Obstetrics and Gynecology, Peking University International Hospital, Beijing, China
| | - Yousheng Yan
- Department of Obstetrics and Gynecology, Peking University International Hospital, Beijing, China.,National Research Institute for Family Planning, Beijing, China
| | - Li Lin
- Department of Obstetrics and Gynecology, Peking University International Hospital, Beijing, China
| |
Collapse
|
16
|
Fernandez-Prado R, Kanbay M, Ortiz A, Perez-Gomez MV. Expanding congenital abnormalities of the kidney and urinary tract (CAKUT) genetics: basonuclin 2 (BNC2) and lower urinary tract obstruction. ANNALS OF TRANSLATIONAL MEDICINE 2019; 7:S226. [PMID: 31656805 DOI: 10.21037/atm.2019.08.73] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Raul Fernandez-Prado
- Division of Nephrology and Hypertension, Dialysis Unit, School of Medicine, IIS-Fundacion Jimenez Diaz, Universidad Autónoma de Madrid, Madrid, Spain
| | - Mehmet Kanbay
- Division of Nephrology, Department of Medicine, Koc University School of Medicine, Istanbul, Turkey
| | - Alberto Ortiz
- Division of Nephrology and Hypertension, Dialysis Unit, School of Medicine, IIS-Fundacion Jimenez Diaz, Universidad Autónoma de Madrid, Madrid, Spain
| | - Maria Vanessa Perez-Gomez
- Division of Nephrology and Hypertension, Dialysis Unit, School of Medicine, IIS-Fundacion Jimenez Diaz, Universidad Autónoma de Madrid, Madrid, Spain
| |
Collapse
|