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Aguech A, Sfaihi L, Alila-Fersi O, Kolsi R, Tlili A, Kammoun T, Fendri A, Fakhfakh F. A novel homozygous PIGO mutation associated with severe infantile epileptic encephalopathy, profound developmental delay and psychomotor retardation: structural and 3D modelling investigations and genotype-phenotype correlation. Metab Brain Dis 2023; 38:2665-2678. [PMID: 37656370 DOI: 10.1007/s11011-023-01276-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 08/07/2023] [Indexed: 09/02/2023]
Abstract
The PIGO gene encodes the GPI-ethanolamine phosphate transferase 3, which is crucial for the final synthetic step of the glycosylphosphatidylinositol-anchor serving to attach various proteins to their cell surface. These proteins are intrinsic for normal neuronal and embryonic development. In the current research work, a clinical investigation was conducted on a patient from a consanguineous family suffering from epileptic encephalopathy, characterized by severe seizures, developmental delay, hypotonia, ataxia and hyperphosphatasia. Molecular analysis was performed using Whole Exome Sequencing (WES). The molecular investigation revealed a novel homozygous variant c.1132C > T in the PIGO gene, in which a highly conserved Leucine was changed to a Phenylalanine (p.L378F). To investigate the impact of the non-synonymous mutation, a 3D structural model of the PIGO protein was generated using the AlphaFold protein structure database as a resource for template-based tertiary structure modeling. A structural analysis by applying some bioinformatic tools on both variants 378L and 378F models predicted the pathogenicity of the non-synonymous mutation and its potential functional and structural effects on PIGO protein. We also discussed the phenotypic and genotypic variability associated with the PIGO deficiency. To our best knowledge, this is the first report of a patient diagnosed with infantile epileptic encephalopathy showing a high elevation of serum alkaline phosphatase level. Our findings, therefore, widen the genotype and phenotype spectrum of GPI-anchor deficiencies and broaden the cohort of patients with PIGO associated epileptic encephalopathy with an elevated serum alkaline phosphatase level.
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Affiliation(s)
- Ameni Aguech
- Molecular Genetics and Functional Laboratory, Faculty of Sciences of Sfax, University of Sfax, Sfax, Tunisia.
| | - Lamia Sfaihi
- Pediatrics Department, Hedi Chaker University Hospital, 3029, Sfax, Tunisia
- Faculty of Medecine of Sfax, University of Sfax, Avenue Magida Boulila, 3029, Sfax, Tunisia
| | - Olfa Alila-Fersi
- Molecular Genetics and Functional Laboratory, Faculty of Sciences of Sfax, University of Sfax, Sfax, Tunisia
| | - Roeya Kolsi
- Pediatrics Department, Hedi Chaker University Hospital, 3029, Sfax, Tunisia
- Faculty of Medecine of Sfax, University of Sfax, Avenue Magida Boulila, 3029, Sfax, Tunisia
| | - Abdelaziz Tlili
- Department of Applied Biology, College of Sciences, University of Sharjah, Sharjah, United Arab Emirates
| | - Thouraya Kammoun
- Pediatrics Department, Hedi Chaker University Hospital, 3029, Sfax, Tunisia
- Faculty of Medecine of Sfax, University of Sfax, Avenue Magida Boulila, 3029, Sfax, Tunisia
| | - Ahmed Fendri
- Laboratory of Biochemistry and Enzymatic Engineering of Lipases, Engineering National School of Sfax (ENIS), University of Sfax, Sfax, Tunisia
| | - Faiza Fakhfakh
- Molecular Genetics and Functional Laboratory, Faculty of Sciences of Sfax, University of Sfax, Sfax, Tunisia.
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2
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Starosta RT, Kerashvili N, Pruitt C, Schultz MJ, Boyer SW, Morava E, Lasio MLD, Grange DK. PIGO-CDG: A case study with a new genotype, expansion of the phenotype, literature review, and nosological considerations. JIMD Rep 2023; 64:424-433. [PMID: 37927489 PMCID: PMC10623102 DOI: 10.1002/jmd2.12396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 08/23/2023] [Accepted: 09/06/2023] [Indexed: 11/07/2023] Open
Abstract
The phosphatidylinositol glycan anchor biosynthesis class O protein (PIGO) enzyme is an important step in the biosynthesis of glycosylphosphatidylinositol (GPI), which is essential for the membrane anchoring of several proteins. Bi-allelic pathogenic variants in PIGO lead to a congenital disorder of glycosylation (CDG) characterized by global developmental delay, an increase in serum alkaline phosphatase levels, congenital anomalies including anorectal, genitourinary, and limb malformations in most patients; this phenotype has been alternately called "Mabry syndrome" or "hyperphosphatasia with impaired intellectual development syndrome 2." We report a 22-month-old female with PIGO deficiency caused by novel PIGO variants. In addition to the Mabry syndrome phenotype, our patient's clinical picture was complicated by intermittent hypoglycemia with signs of functional hyperinsulinism, severe secretory diarrhea, and osteopenia with a pathological fracture, thus, potentially expanding the known phenotype of this disorder, although more studies are necessary to confirm these associations. We also provide an updated review of the literature, and propose unifying the nomenclature of PIGO deficiency as "PIGO-CDG," which reflects its pathophysiology and position in the broad scope of metabolic disorders and congenital disorders of glycosylation.
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Affiliation(s)
- Rodrigo Tzovenos Starosta
- Division of Genetics and Genomic Medicine, Department of PediatricsWashington University in St. LouisClaytonMissouriUSA
| | - Nino Kerashvili
- Division of Pediatric Neurology, Department of NeurologyWashington University in St. LouisClaytonMissouriUSA
| | - Cassandra Pruitt
- Division of Academic Pediatrics, Department of PediatricsWashington University in St. LouisClaytonMissouriUSA
| | - Matthew J. Schultz
- Department of Laboratory Medicine and PathologyMayo ClinicRochesterMinnesotaUSA
| | | | - Eva Morava
- Department of Clinical GenomicsMayo ClinicRochesterMinnesotaUSA
| | - Maria Laura Duque Lasio
- Division of Genetics and Genomic Medicine, Department of PediatricsWashington University in St. LouisClaytonMissouriUSA
- Division of Laboratory and Genomic Medicine, Department of Pathology and ImmunologyWashington University in St. LouisClaytonMissouriUSA
| | - Dorothy K. Grange
- Division of Genetics and Genomic Medicine, Department of PediatricsWashington University in St. LouisClaytonMissouriUSA
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3
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Hutny M, Lipinski P, Jezela-Stanek A. Characteristics of Neuroimaging and Behavioural Phenotype in Polish Patients with PIGV-CDG-An Observational Study and Literature Review. Genes (Basel) 2023; 14:1208. [PMID: 37372388 DOI: 10.3390/genes14061208] [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: 04/26/2023] [Revised: 05/28/2023] [Accepted: 05/29/2023] [Indexed: 06/29/2023] Open
Abstract
Congenital disorders of glycosylation (CDGs) are a wide group of genetic diseases characterised by a severe clinical spectrum, consisting of developmental delays, dysmorphisms, and neurological deficits. Mutations in the PIGV gene lead to a disorder called hyperphosphatasia with impaired intellectual development syndrome 1 (HPMRS1), distinct from other CDGs in terms of hyperphosphatemia related to abnormal ALP activity and brachytelephalangy. This article discusses the phenotype of six Polish patients with HPMRS1 with a special focus on behavioural and imaging features, which were not addressed in 26 previously reported cases. The medical records of six patients aged 6 to 22 years were collected and analysed. In all cases, the same PIGV homozygotic mutation (c.1022C>A; p.Ala341Glu) was found, although the patients presented a diverse spectrum of neurological and developmental disorders, concerning in most cases the muscular tonus and general developmental delay. The most prevalent dysmorphic features included hypertelorism, high palate, and finger anomalies, whereas other characteristics present in all previously described cases, such as a short, broad nose and brachytelephalangy, were less frequently observed. Similarly to previous reports, the magnetic resonance (MR) and computed tomography (CT) head scans returned varied results, including physiological and pathological brain images in equal measure, the latter of which consisted of cortical atrophy, delayed myelination, hydrocephalus, and hypoplastic corpus callosum. Each patient exhibited symptoms characteristic of autism spectrum disorders, especially in terms of attention deficits, as well as controlling and expressing emotions. The most common type of sensory processing disorder was over-responsivity. Despite the low prevalence of HPMRS1, the patients reported in the literature presented a rather uniform phenotype, which does not correspond with the one found in each individual of the studied group. Behavioural disorders and sensory impairment require additional care and awareness considering the global developmental delay often observed in these patients.
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Affiliation(s)
- Michal Hutny
- Students' Scientific Society, Department of Paediatric Neurology, Faculty of Medical Sciences in Katowice, Medical University of Silesia, 40-752 Katowice, Poland
| | - Patryk Lipinski
- Department of Pediatrics, Nutrition and Metabolic Diseases, The Children's Memorial Health Institute, 04-730 Warsaw, Poland
| | - Aleksandra Jezela-Stanek
- Department of Genetics and Clinical Immunology, National Institute of Tuberculosis and Lung Diseases, 01-138 Warsaw, Poland
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4
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Thompson MD, Li X, Spencer-Manzon M, Andrade DM, Murakami Y, Kinoshita T, Carpenter TO. Excluding Digenic Inheritance of PGAP2 and PGAP3 Variants in Mabry Syndrome (OMIM 239300) Patient: Phenotypic Spectrum Associated with PGAP2 Gene Variants in Hyperphosphatasia with Mental Retardation Syndrome-3 (HPMRS3). Genes (Basel) 2023; 14:genes14020359. [PMID: 36833286 PMCID: PMC9957281 DOI: 10.3390/genes14020359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 01/20/2023] [Accepted: 01/25/2023] [Indexed: 01/31/2023] Open
Abstract
We present a case report of a child with features of hyperphosphatasia with neurologic deficit (HPMRS) or Mabry syndrome (MIM 239300) with variants of unknown significance in two post-GPI attachments to proteins genes, PGAP2 and PGAP3, that underlie HPMRS 3 and 4. BACKGROUND In addition to HPMRS 3 and 4, disruption of four phosphatidylinositol glycan (PIG) biosynthesis genes, PIGV, PIGO, PIGW and PIGY, result in HPMRS 1, 2, 5 and 6, respectively. METHODS Targeted exome panel sequencing identified homozygous variants of unknown significance (VUS) in PGAP2 c:284A>G and PGAP3 c:259G>A. To assay the pathogenicity of these variants, we conducted a rescue assay in PGAP2 and PGAP3 deficient CHO cell lines. RESULTS Using a strong (pME) promoter, the PGAP2 variant did not rescue activity in CHO cells and the protein was not detected. Flow cytometric analysis showed that CD59 and CD55 expression on the PGAP2 deficient cell line was not restored by variant PGAP2. By contrast, activity of the PGAP3 variant was similar to wild-type. CONCLUSIONS For this patient with Mabry syndrome, the phenotype is likely to be predominantly HPMRS3: resulting from autosomal recessive inheritance of NM_001256240.2 PGAP2 c:284A>G, p.Tyr95Cys. We discuss strategies for establishing evidence for putative digenic inheritance in GPI deficiency disorders.
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Affiliation(s)
- Miles D. Thompson
- Adult Genetic Epilepsy (AGE) Program, Toronto Western Hospital, Krembil Brain Institute, Toronto, ON M5T, Canada
- Correspondence: (M.D.T.); (T.O.C.)
| | - Xueying Li
- Osaka University, 3-1 Yamada-Oka, Osaka 565-0871, Japan
| | | | - Danielle M. Andrade
- Adult Genetic Epilepsy (AGE) Program, Toronto Western Hospital, Krembil Brain Institute, Toronto, ON M5T, Canada
- Division of Neurology, Department of Medicine, University of Toronto, Toronto, ON M5S, Canada
| | | | | | - Thomas O. Carpenter
- Yale Pediatrics (Endocrinology), Yale University School of Medicine, New Haven, CT 06521, USA
- Correspondence: (M.D.T.); (T.O.C.)
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5
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Messina M, Manea E, Cullup T, Tuschl K, Batzios S. Hyperphosphatasia with mental retardation syndrome 3: Cerebrospinal fluid abnormalities and correction with pyridoxine and Folinic acid. JIMD Rep 2023; 64:42-52. [PMID: 36636587 PMCID: PMC9830023 DOI: 10.1002/jmd2.12347] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 09/16/2022] [Accepted: 10/25/2022] [Indexed: 11/24/2022] Open
Abstract
Glycosylphosphatidylinositol anchored proteins (GPI-APs) represent a class of molecules attached to the external leaflet of the plasma membrane by the GPI anchor where they play important roles in numerous cellular processes including neurogenesis, cell adhesion, immune response and signalling. Within the group of GPI anchor defects, six present with the clinical phenotype of Hyperphosphatasia with Mental Retardation Syndrome (HPMRS, Mabry Syndrome) characterized by moderate to severe intellectual disability, dysmorphic features, hypotonia, seizures and persistent hyperphosphatasia. We report the case of a 5-year-old female with global developmental delay associated with precocious puberty and persistently raised plasma alkaline phosphatase. Targeted next generation sequencing analysis of the HPMRS genes identified novel compound heterozygous variants in the PGAP2 gene (c.103del p.(Leu35Serfs*90)and c.134A > Gp.(His45Arg)) consistent with the diagnosis of HPMRS type 3. Cerebrospinal fluid (CSF) neurotransmitter analysis showed low levels of pyridoxal phosphate and 5-methyltetrahydrofolate and raised homovanillic acid. Supplementation with pyridoxine and folinic acid led to normalization of biochemical abnormalities. The patient continues to make developmental progress with significant improvement in speech and fine motor skills. Our reported case expands the clinical spectrum of HPMRS3 in which multisystem involvement is being increasingly recognized. Furthermore, it shows that miss-targeting GPI-APs and the effect on normal cellular function could provide a physiopathologic explanation for the CSF biochemical abnormalities with management implications for a group of disorders that currently has no treatment that can lead possibly to improved clinical outcomes.
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Affiliation(s)
- Martina Messina
- Metabolic Medicine DepartmentGreat Ormond Street Hospital for ChildrenLondonUK
| | - Emanuela Manea
- Metabolic Medicine DepartmentGreat Ormond Street Hospital for ChildrenLondonUK
| | - Thomas Cullup
- North Thames Genomic Laboratory HubGreat Ormond Street Hospital for ChildrenLondonUK
| | - Karin Tuschl
- Metabolic Medicine DepartmentGreat Ormond Street Hospital for ChildrenLondonUK
- University College London Great Ormond Street Institute for ChildrenLondonUK
| | - Spyros Batzios
- Metabolic Medicine DepartmentGreat Ormond Street Hospital for ChildrenLondonUK
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Tanigawa J, Nabatame S, Tominaga K, Nishimura Y, Maegaki Y, Kinosita T, Murakami Y, Ozono K. High-dose pyridoxine treatment for inherited glycosylphosphatidylinositol deficiency. Brain Dev 2021; 43:680-687. [PMID: 33824024 DOI: 10.1016/j.braindev.2021.02.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 02/21/2021] [Accepted: 02/28/2021] [Indexed: 11/30/2022]
Abstract
OBJECTIVE We aimed to assess the efficacy and safety of high-dose pyridoxine treatment for seizures and its effects on development in patients with inherited glycosylphosphatidylinositol deficiencies (IGDs). METHODS In this prospective open-label multicenter pilot study, we enrolled patients diagnosed with IGDs using flow cytometry and/or genetic tests. The patients received oral pyridoxine (20-30 mg/kg/day) for 1 year, in addition to previous treatment. RESULTS All nine enrolled patients (mean age: 66.3 ± 44.3 months) exhibited marked decreases in levels of CD16, a glycosylphosphatidylinositol-anchored protein, on blood granulocytes. The underlying genetic causes of IGDs were PIGO, PIGL, and unknown gene mutations in two, two, and five patients, respectively. Six patients experienced seizures, while all patients presented with developmental delay (mean developmental age: 11.1 ± 8.1 months). Seizure frequencies were markedly (>50%) and drastically (>90%) reduced in three and one patients who experienced seizures, respectively. None of the patients presented with seizure exacerbation. Eight of nine patients exhibited modest improvements in development (P = 0.14). No adverse events were observed except for mild transient diarrhea in one patient. CONCLUSION One year of daily high-dose pyridoxine treatment was effective in the treatment of seizures in more than half of our patients with IGDs and modestly improved development in the majority of them. Moreover, such treatment was reasonably safe. These findings indicate that high-dose pyridoxine treatment may be effective against seizures in patients with IGDs, although further studies are required to confirm our findings. (University Hospital Medical Information Network Clinical Trials Registry [UMIN-CTR] number: UMIN000024185.).
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Affiliation(s)
- Junpei Tanigawa
- Department of Pediatrics, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Shin Nabatame
- Department of Pediatrics, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Koji Tominaga
- Department of Pediatrics, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan; Division of Developmental Neuroscience, United Graduate School of Child Development, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Yoko Nishimura
- Division of Child Neurology, Institute of Neurological Sciences, Faculty of Medicine, Tottori University, 36-1 Nishi-cho, Yonago, Tottori 683-8504, Japan
| | - Yoshihiro Maegaki
- Division of Child Neurology, Institute of Neurological Sciences, Faculty of Medicine, Tottori University, 36-1 Nishi-cho, Yonago, Tottori 683-8504, Japan
| | - Taroh Kinosita
- Research Institute for Microbial Diseases and World Premier International Immunology Frontier Research Center, Osaka University, 3-1 Yamadaoka Suita, Osaka 565-0871, Japan
| | - Yoshiko Murakami
- Research Institute for Microbial Diseases and World Premier International Immunology Frontier Research Center, Osaka University, 3-1 Yamadaoka Suita, Osaka 565-0871, Japan
| | - Keiichi Ozono
- Department of Pediatrics, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan
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Wang M, Lin Y, Zhou S, Cui Y, Feng Q, Yan W, Xiang H. Genetic Mapping of Climbing and Mimicry: Two Behavioral Traits Degraded During Silkworm Domestication. Front Genet 2020; 11:566961. [PMID: 33391338 PMCID: PMC7773896 DOI: 10.3389/fgene.2020.566961] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Accepted: 11/17/2020] [Indexed: 11/13/2022] Open
Abstract
Behavioral changes caused by domestication in animals are an important issue in evolutionary biology. The silkworm, Bombyx mori, is an ideal fully domesticated insect model for studying both convergent domestication and behavior evolution. We explored the genetic basis of climbing for foraging and mimicry, two degraded behaviors during silkworm domestication, in combination of bulked segregant analysis (BSA) and selection sweep screening. One candidate gene, ASNA1, located in the 3-5 Mb on chromosome 19, harboring a specific non-synonymous mutation in domestic silkworm, might be involved in climbing ability. This mutation was under positive selection in Lepidoptera, strongly suggesting its potential function in silkworm domestication. Nine candidate domesticated genes related to mimicry were identified on chromosomes 13, 21, and 27. Most of the candidate domesticated genes were generally expressed at higher levels in the brain of the wild silkworm. This study provides valuable information for deciphering the molecular basis of behavioral changes associated with silkworm domestication.
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Affiliation(s)
- Man Wang
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Yongjian Lin
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Shiyi Zhou
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Yong Cui
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Qili Feng
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Wei Yan
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Hui Xiang
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, China
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Wu T, Yin F, Guang S, He F, Yang L, Peng J. The Glycosylphosphatidylinositol biosynthesis pathway in human diseases. Orphanet J Rare Dis 2020; 15:129. [PMID: 32466763 PMCID: PMC7254680 DOI: 10.1186/s13023-020-01401-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 05/06/2020] [Indexed: 01/15/2023] Open
Abstract
Glycosylphosphatidylinositol biosynthesis defects cause rare genetic disorders characterised by developmental delay/intellectual disability, seizures, dysmorphic features, and diverse congenital anomalies associated with a wide range of additional features (hypotonia, hearing loss, elevated alkaline phosphatase, and several other features). Glycosylphosphatidylinositol functions as an anchor to link cell membranes and protein. These proteins function as enzymes, adhesion molecules, complement regulators, or co-receptors in signal transduction pathways. Biallelic variants involved in the glycosylphosphatidylinositol anchored proteins biosynthetic pathway are responsible for a growing number of disorders, including multiple congenital anomalies-hypotonia-seizures syndrome; hyperphosphatasia with mental retardation syndrome/Mabry syndrome; coloboma, congenital heart disease, ichthyosiform dermatosis, mental retardation, and ear anomalies/epilepsy syndrome; and early infantile epileptic encephalopathy-55. This review focuses on the current understanding of Glycosylphosphatidylinositol biosynthesis defects and the associated genes to further understand its wide phenotype spectrum.
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Affiliation(s)
- Tenghui Wu
- Department of Pediatrics, XiangYa Hospital, Central South University, 87 Xiangya Road, Changsha, 410008, Hunan Province, China.,Hunan Children's Mental Disorders Research Center, XiangYa Hospital, Central South University, 87 Xiangya Road, Changsha, 410008, Hunan Province, China
| | - Fei Yin
- Department of Pediatrics, XiangYa Hospital, Central South University, 87 Xiangya Road, Changsha, 410008, Hunan Province, China.,Hunan Children's Mental Disorders Research Center, XiangYa Hospital, Central South University, 87 Xiangya Road, Changsha, 410008, Hunan Province, China
| | - Shiqi Guang
- Department of Pediatrics, XiangYa Hospital, Central South University, 87 Xiangya Road, Changsha, 410008, Hunan Province, China.,Hunan Children's Mental Disorders Research Center, XiangYa Hospital, Central South University, 87 Xiangya Road, Changsha, 410008, Hunan Province, China
| | - Fang He
- Department of Pediatrics, XiangYa Hospital, Central South University, 87 Xiangya Road, Changsha, 410008, Hunan Province, China.,Hunan Children's Mental Disorders Research Center, XiangYa Hospital, Central South University, 87 Xiangya Road, Changsha, 410008, Hunan Province, China
| | - Li Yang
- Department of Pediatrics, XiangYa Hospital, Central South University, 87 Xiangya Road, Changsha, 410008, Hunan Province, China.,Hunan Children's Mental Disorders Research Center, XiangYa Hospital, Central South University, 87 Xiangya Road, Changsha, 410008, Hunan Province, China
| | - Jing Peng
- Department of Pediatrics, XiangYa Hospital, Central South University, 87 Xiangya Road, Changsha, 410008, Hunan Province, China. .,Hunan Children's Mental Disorders Research Center, XiangYa Hospital, Central South University, 87 Xiangya Road, Changsha, 410008, Hunan Province, China.
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9
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Analyzing clinical and genetic characteristics of a cohort with multiple congenital anomalies-hypotonia-seizures syndrome (MCAHS). Orphanet J Rare Dis 2020; 15:78. [PMID: 32220244 PMCID: PMC7099766 DOI: 10.1186/s13023-020-01365-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 03/18/2020] [Indexed: 12/28/2022] Open
Abstract
Objective To summarize and extend the phenotypic characterization of Multiple Congenital Anomalies-Hypotonia-Seizures Syndrome, and to discuss genotype-phenotype correlations. Methods Collecting clinical information of 17 patients with pathogenic variants in PIGN, PIGA, and PIGT. Genetic studies were performed on all patients. Results There were 7 patients with 15 PIGN mutations (one patient carrying 3 mutations), 8 patients with 8 PIGA mutations, and 2 patients with 5 PIGT mutations (one patient carrying 3 mutations). All patients had epilepsy and developmental delay, with 71% of them showed hypotonia. And among these patients’ various seizure types, the focal seizure was the most common one. Eighty-two percent patients showed a significant relationship between seizures and fever. Serum ALP was elevated in one patient with PIGN mutations and in two patients with PIGA mutations. Brain MRI showed enlarged subarachnoid space in 56% of patients. Some other different characteristics had also been found in our patients: First, atypical absence seizures presented in three patients with PIGN mutations; Second, diffuse slow waves mixed with focal or multifocal discharges of interictal EEG in 88% cases with PIGA-deficient; Third, phenotypes of seven out of eight patients with PIGA mutations were difficult to be classified as severe or less severe group; Last, mild neurological symptoms and developmental status rather than severe conditions occurred in one patient with PIGT mutations. Conclusion With epilepsy, developmental delay, and/or hypotonia as common features, the knowledge of MCAHS in terms of phenotype and genotype has been expanded. In cases with PIGN-deficient, we expanded the types of atypical absence seizures, and described one patient with elevated serum ALP. Focal seizures with diffuse slow waves mixed with focal or multifocal discharges on EEG rather than infantile spasms with hypsarrhythmia, which as previously reported were often seen in our patients with PIGA mutations. The classifications of phenotypes caused by PIGA mutations should be more continuous than discrete. The mild phenotype of one patient with PIGT mutations expanded the clinical presentation of MCAHS3.
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10
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Thompson MD, Knaus AA, Barshop BA, Caliebe A, Muhle H, Nguyen TTM, Baratang NV, Kinoshita T, Percy ME, Campeau PM, Murakami Y, Cole DE, Krawitz PM, Mabry CC. A post glycosylphosphatidylinositol (GPI) attachment to proteins, type 2 (PGAP2) variant identified in Mabry syndrome index cases: Molecular genetics of the prototypical inherited GPI disorder. Eur J Med Genet 2019; 63:103822. [PMID: 31805394 DOI: 10.1016/j.ejmg.2019.103822] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 11/12/2019] [Accepted: 11/30/2019] [Indexed: 10/25/2022]
Abstract
We report that recessive inheritance of a post-GPI attachment to proteins 2 (PGAP2) gene variant results in the hyperphosphatasia with neurologic deficit (HPMRS) phenotype described by Mabry et al., in 1970. HPMRS, or Mabry syndrome, is now known to be one of 21 inherited glycosylphosphatidylinositol (GPI) deficiencies (IGDs), or GPI biosynthesis defects (GPIBDs). Bi-allelic mutations in at least six genes result in HPMRS phenotypes. Disruption of four phosphatidylinositol glycan (PIG) biosynthesis genes, PIGV, PIGO, PIGW and PIGY, expressed in the endoplasmic reticulum, result in HPMRS 1, 2, 5 and 6; disruption of the PGAP2 and PGAP3 genes, necessary for stabilizing the association of GPI anchored proteins (AP) with the Golgi membrane, result in HPMRS 3 and 4. We used exome sequencing to identify a novel homozygous missense PGAP2 variant NM_014489.3:c.881C > T, p.Thr294Met in two index patients and targeted sequencing to identify this variant in an unrelated patient. Rescue assays were conducted in two PGAP2 deficient cell lines, PGAP2 KO cells generated by CRISPR/Cas9 and PGAP2 deficient CHO cells, in order to examine the pathogenicity of the PGAP2 variant. First, we used the CHO rescue assay to establish that the wild type PGAP2 isoform 1, translated from transcript 1, is less active than the wild type PGAP2 isoform 8, translated from transcript 12 (alternatively spliced to omit exon 3). As a result, in our variant rescue assays, we used the more active NM_001256240.2:c.698C > T, p.Thr233Met isoform 8 instead of NM_014489.3:c.881C > T, p.Thr294Met isoform 1. Flow cytometric analysis showed that restoration of cell surface CD59 and CD55 with variant PGAP2 isoform 8, driven by the weak (pTA FLAG) promoter, was less efficient than wild type isoform 8. Therefore, we conclude that recessive inheritance of c.881C > T PGAP2, expressed as the hypomorphic PGAP2 c.698C > T, p.Thr233Met isoform 8, results in prototypical Mabry phenotype, HPMRS3 (GPIBD 8 [MIM: 614207]). This study highlights the need for long-term follow up of individuals with rare diseases in order to ensure that they benefit from innovations in diagnosis and treatment.
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Affiliation(s)
- Miles D Thompson
- Department of Pediatrics, UCSD School of Medicine, United States.
| | - Alexej A Knaus
- Institute for Genomic Statistics and Bioinformatics, University Hospital Bonn, Rheinische Friedrich-Wilhelms-Universität Bonn, Germany
| | - Bruce A Barshop
- Department of Pediatrics, UCSD School of Medicine, United States
| | - Almuth Caliebe
- Department of Human Genetics, University Hospital Schleswig-Holstein, Campus Kiel, Christian-Albrechts-University, Kiel, Germany
| | - Hiltrud Muhle
- Department of Human Genetics, University Hospital Schleswig-Holstein, Campus Kiel, Christian-Albrechts-University, Kiel, Germany
| | - Thi Tuyet Mai Nguyen
- Centre Hospitalier Universitaire Sainte Justine Research Center, University of Montreal, Canada
| | - Nissan V Baratang
- Centre Hospitalier Universitaire Sainte Justine Research Center, University of Montreal, Canada
| | - Taroh Kinoshita
- Research Institute for Microbial Diseases, Osaka University, Japan
| | - Maire E Percy
- Department of Physiology, University of Toronto, Canada; Department of Obstetrics and Gynaecology, University of Toronto, Canada
| | - Philippe M Campeau
- Centre Hospitalier Universitaire Sainte Justine Research Center, University of Montreal, Canada
| | - Yoshiko Murakami
- Research Institute for Microbial Diseases, Osaka University, Japan
| | - David E Cole
- Laboratory Medicine and Pathobiology, University of Toronto, Canada
| | - Peter M Krawitz
- Institute for Genomic Statistics and Bioinformatics, University Hospital Bonn, Rheinische Friedrich-Wilhelms-Universität Bonn, Germany
| | - C Charlton Mabry
- Department of Pediatrics, College of Medicine, University of Kentucky, United States
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11
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Holtz AM, Harrington AW, McNamara ER, Kielian A, Soul JS, Martinez-Ojeda M, Levy PT. Expanding the phenotypic spectrum of Mabry Syndrome with novel PIGO gene variants associated with hyperphosphatasia, intractable epilepsy, and complex gastrointestinal and urogenital malformations. Eur J Med Genet 2019; 63:103802. [PMID: 31698102 DOI: 10.1016/j.ejmg.2019.103802] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 10/05/2019] [Accepted: 10/30/2019] [Indexed: 11/30/2022]
Abstract
Mabry syndrome is a glycophosphatidylinositol (GPI) deficiency characterized by intellectual disability, distinctive facial features, intractable seizures, and hyperphosphatasia. We expand the phenotypic spectrum of inherited GPI deficiencies with novel bi-allelic phosphatidylinositol glycan anchor biosynthesis class O (PIGO) variants in a neonate who presented with intractable epilepsy and complex gastrointestinal and urogenital malformations.
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Affiliation(s)
- Alexander M Holtz
- Department of Pediatrics, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA
| | - Amanda W Harrington
- Department of Surgery, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA
| | - Erin R McNamara
- Department of Urology, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA
| | - Agnieszka Kielian
- Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA
| | - Janet S Soul
- Department of Pediatrics, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA; Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA
| | - Mayra Martinez-Ojeda
- Department of Pediatrics, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA
| | - Philip T Levy
- Department of Pediatrics, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA.
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12
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Abstract
Introduction: Vitamin B6 dependent epilepsies are a group of treatable diseases (ALDH7A1 deficiency, PNPO deficiency, PLP binding protein deficiency, hyperprolinaemia type II and hypophosphatasia and glycosylphosphatidylinositol anchor synthesis defects) responding to pyridoxine or pyridoxal-5I-phosphate. Areas covered: A critical review was conducted on the therapeutic management of all the reported patients with genetically confirmed diagnoses of diseases affecting vitamin B6 metabolism and presenting with pyridoxine or pyridoxal-5I-phosphate dependent-seizures. Data about safety and efficacy were analyzed as well as the management of supplementation with pyridoxine or pyridoxal-5I-phosphate both in the acute phases and in the maintenance therapies. The authors also analyzed alternative therapeutic strategies for ALDH7A1 deficiency (lysine-restricted diet, arginine supplementation, oligonucleotide antisense therapy, upstream inhibition of aminoadipic semialdehyde synthase). Expert opinion: The administration of pyridoxine or pyridoxal-5I-phosphate should be considered in all intractable seizures also beyond the first year of life. Lysine restricted diet and arginine supplementation should be introduced in all the confirmed ALDH7A1 deficient patients. Pre or post-natal supplementation with pyridoxine should be given in familial cases until an eventual molecular genetic disconfirmation. Minor data about alternative therapies are available for other disorders of vitamin B6 metabolism.
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Affiliation(s)
- Mario Mastrangelo
- Division of Child Neurology and Infantile Psychiatry, Department of Human Neurosciences, Sapienza University of Rome , Roma , Italy
| | - Serena Cesario
- Division of Child Neurology and Infantile Psychiatry, Department of Human Neurosciences, Sapienza University of Rome , Roma , Italy
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13
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Balobaid A, Ben-Omran T, Ramzan K, Altassan R, Almureikhi M, Musa S, Al-Hashmi N, Al-Owain M, Al-Zaidan H, Al-Hassnan Z, Imtiaz F, Al-Sayed M. Delineating the phenotypic spectrum of hyperphosphatasia with mental retardation syndrome 4 in 14 patients of Middle-Eastern origin. Am J Med Genet A 2018; 176:2850-2857. [PMID: 30345601 DOI: 10.1002/ajmg.a.40627] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2018] [Revised: 08/13/2018] [Accepted: 08/13/2018] [Indexed: 12/31/2022]
Abstract
Hyperphosphatasia with mental retardation syndrome 4 (HPMRS4) is a rare autosomal recessive condition caused by an impairment of glycosylphophatidylinositol biosynthesis. The cardinal features of HPMRS4 include; characteristic facial features, severe intellectual disability and various neurologic abnormalities. We report here detailed clinical, biochemical, and molecular findings of 14 patients clinically suspected to have HPMRS4, from three Middle-Eastern Countries; Saudi Arabia, Qatar, and Oman. All patients in our series presented with the cardinal features pointing to HPMRS4 and with an elevated alkaline phosphatase level. Five patients had megalocornea, which have been reported recently in an Arab patient. Additionally, fracture, bilateral coxa valga, camptodactyly, truncal obesity, and hyperpigmented macules of the upper thigh, each was seen once and was not described before with HPMRS4. Additional clinical and radiological findings are described, supporting the novel clinical and radiological findings recently described in Egyptian patients. The utilization of homozygosity mapping coupled with PGAP3 sequencing and whole exome sequencing facilitated the mutation detection in these patients. These missense mutations include c.320C > T (p.S107 L), c.850C > T (p.H284Y), and c.851A > G (p.H284R) in the PGAP3 gene. We believe that the recurrent mutations identified in our cohort may represent founder mutations in big tribes from a certain geographical region of Saudi Arabia, Qatar, and Oman. Therefore, in case of a clinical suspicion of HPMRS4 in these populations, targeted genetic testing for the identified mutations should be performed first to expedite the genetic diagnosis.
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Affiliation(s)
- Ameera Balobaid
- Department of Medical Genetics, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia.,College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
| | - Tawfeg Ben-Omran
- Clinical and Metabolic Genetics, Department of Pediatrics, Hamad Medical Corporation, Qatar
| | - Khushnooda Ramzan
- Department of Genetics, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia
| | - Ruqaiah Altassan
- Department of Medical Genetics, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia
| | - Mariam Almureikhi
- Clinical and Metabolic Genetics, Department of Pediatrics, Hamad Medical Corporation, Qatar
| | - Sara Musa
- Clinical and Metabolic Genetics, Department of Pediatrics, Hamad Medical Corporation, Qatar
| | | | - Mohammed Al-Owain
- Department of Medical Genetics, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia.,College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
| | - Hamad Al-Zaidan
- Department of Medical Genetics, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia.,College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
| | - Zuhair Al-Hassnan
- Department of Medical Genetics, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia.,College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
| | - Faiqa Imtiaz
- Department of Genetics, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia
| | - Moeenaldeen Al-Sayed
- Department of Medical Genetics, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia.,College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
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14
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Liu A, Yang X, Yang X, Wu Q, Zhang J, Sun D, Yang Z, Jiang Y, Wu X, Wei L, Zhang Y. Mosaicism and incomplete penetrance of PCDH19 mutations. J Med Genet 2018; 56:81-88. [PMID: 30287595 PMCID: PMC6581080 DOI: 10.1136/jmedgenet-2017-105235] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2017] [Revised: 08/25/2018] [Accepted: 08/30/2018] [Indexed: 02/02/2023]
Abstract
BACKGROUND Mutations in the PCDH19 gene have mainly been reported in female patients with epilepsy. To date, PCDH19 mutations have been reported in hundreds of females and only in 10 mosaic male epileptic patients with mosaicism. OBJECTIVE We aimed to investigate the occurrence of mosaic PCDH19 mutations in 42 families comprising at least one patient with PCDH19-related epilepsy. METHODS Two male patients with mosaic PCDH19 variants were identified using targeted next-generation sequencing. Forty female patients with PCDH19 variants were identified by Sanger sequencing and Multiple Ligation Probe Amplification (MLPA). Microdroplet digital PCR was used to quantify the mutant allelic fractions (MAFs) in 20 families with PCDH19 variants. RESULTS Five mosaic individuals, four males and one female, were identified in total. Mosaic variant was confirmed in multiple somatic tissues from one male patient and in blood from the other male patient. Among 22 female patients harbouring a newly occurred PCDH19 variant identified by Sanger sequencing and MLPA, Sanger sequencing revealed two mosaic fathers (9%, 2/22), one with two affected daughters and the other with an affected child. Two asymptomatic mosaic fathers were confirmed as gonosomal mosaicism, with MAFs ranging from 4.16% to 37.38% and from 1.27% to 19.13%, respectively. In 11 families with apparent de novo variants, 1 female patient was identified as a mosaic with a blood MAF of 26.72%. CONCLUSION Our study provides new insights into phenotype-genotype correlations in PCDH19 related epilepsy and the finding of high-frequency mosaicism has important implications for genetic counselling.
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Affiliation(s)
- Aijie Liu
- Department of Pediatrics, Peking University First Hospital, Beijing, China.,Department of Pediatric Neurology, Capital Institute of Pediatrics, Beijing, China
| | - Xiaoxu Yang
- Center for Bioinformatics, State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, China
| | - Xiaoling Yang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Qixi Wu
- School of Life Sciences, Peking University, Beijing, China.,Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
| | - Jing Zhang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Dan Sun
- Department of Neurology, Wuhan Children's Hospital, Wuhan, China
| | - Zhixian Yang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Yuwu Jiang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Xiru Wu
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Liping Wei
- Center for Bioinformatics, State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, China
| | - Yuehua Zhang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
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15
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Nguyen TTM, Murakami Y, Wigby KM, Baratang NV, Rousseau J, St-Denis A, Rosenfeld JA, Laniewski SC, Jones J, Iglesias AD, Jones MC, Masser-Frye D, Scheuerle AE, Perry DL, Taft RJ, Le Deist F, Thompson M, Kinoshita T, Campeau PM. Mutations in PIGS, Encoding a GPI Transamidase, Cause a Neurological Syndrome Ranging from Fetal Akinesia to Epileptic Encephalopathy. Am J Hum Genet 2018; 103:602-611. [PMID: 30269814 DOI: 10.1016/j.ajhg.2018.08.014] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 08/23/2018] [Indexed: 11/17/2022] Open
Abstract
Inherited GPI deficiencies (IGDs) are a subset of congenital disorders of glycosylation that are increasingly recognized as a result of advances in whole-exome sequencing (WES) and whole-genome sequencing (WGS). IGDs cause a series of overlapping phenotypes consisting of seizures, dysmorphic features, multiple congenital malformations, and severe intellectual disability. We present a study of six individuals from three unrelated families in which WES or WGS identified bi-allelic phosphatidylinositol glycan class S (PIGS) biosynthesis mutations. Phenotypes included severe global developmental delay, seizures (partly responding to pyridoxine), hypotonia, weakness, ataxia, and dysmorphic facial features. Two of them had compound-heterozygous variants c.108G>A (p.Trp36∗) and c.101T>C (p.Leu34Pro), and two siblings of another family were homozygous for a deletion and insertion leading to p.Thr439_Lys451delinsArgLeuLeu. The third family had two fetuses with multiple joint contractures consistent with fetal akinesia. They were compound heterozygous for c.923A>G (p.Glu308Gly) and c.468+1G>C, a splicing mutation. Flow-cytometry analyses demonstrated that the individuals with PIGS mutations show a GPI-AP deficiency profile. Expression of the p.Trp36∗ variant in PIGS-deficient HEK293 cells revealed only partial restoration of cell-surface GPI-APs. In terms of both biochemistry and phenotype, loss of function of PIGS shares features with PIGT deficiency and other IGDs. This study contributes to the understanding of the GPI-AP biosynthesis pathway by describing the consequences of PIGS disruption in humans and extending the family of IGDs.
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Affiliation(s)
- Thi Tuyet Mai Nguyen
- Centre Hospitalier Universitaire Sainte Justine Research Center, University of Montreal, Montreal, QC H3T1C5, Canada
| | - Yoshiko Murakami
- Research Institute for Microbial Diseases, Osaka University, Osaka 565-0871, Japan
| | - Kristen M Wigby
- Department of Pediatrics, University of California, San Diego, San Diego, CA 92093, USA
| | - Nissan V Baratang
- Centre Hospitalier Universitaire Sainte Justine Research Center, University of Montreal, Montreal, QC H3T1C5, Canada
| | - Justine Rousseau
- Centre Hospitalier Universitaire Sainte Justine Research Center, University of Montreal, Montreal, QC H3T1C5, Canada
| | - Anik St-Denis
- Centre Hospitalier Universitaire Sainte Justine Research Center, University of Montreal, Montreal, QC H3T1C5, Canada
| | - Jill A Rosenfeld
- Department of Molecular & Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | | | - Julie Jones
- Greenwood Genetic Center, Greenwood, SC 29646, USA
| | - Alejandro D Iglesias
- NewYork-Presbyterian Morgan Stanley Children's Hospital, New York, NY 10032, USA
| | - Marilyn C Jones
- Department of Pediatrics, University of California, San Diego, San Diego, CA 92093, USA
| | | | | | | | | | - Françoise Le Deist
- Centre Hospitalier Universitaire Sainte Justine Research Center, University of Montreal, Montreal, QC H3T1C5, Canada
| | - Miles Thompson
- Department of Pediatrics, University of California, San Diego, San Diego, CA 92093, USA
| | - Taroh Kinoshita
- Research Institute for Microbial Diseases, Osaka University, Osaka 565-0871, Japan
| | - Philippe M Campeau
- Centre Hospitalier Universitaire Sainte Justine Research Center, University of Montreal, Montreal, QC H3T1C5, Canada.
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16
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Yang J, Wang Q, Zhuo Q, Tian H, Li W, Luo F, Zhang J, Bi D, Peng J, Zhou D, Xin H. A likely pathogenic variant putatively affecting splicing of PIGA identified in a multiple congenital anomalies hypotonia-seizures syndrome 2 (MCAHS2) family pedigree via whole-exome sequencing. Mol Genet Genomic Med 2018; 6:739-748. [PMID: 29974678 PMCID: PMC6160699 DOI: 10.1002/mgg3.428] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Revised: 04/25/2018] [Accepted: 06/11/2018] [Indexed: 12/18/2022] Open
Abstract
Background Glycosylphosphatidylinositol (GPI) anchoring is a special type of protein posttranslational modification, by which proteins with diverse function are attached to cell membrane through a covalent linkage between the protein and the glycolipid. Phosphatidylinositol glycan anchor biosynthesis class A (PIGA) is a key enzyme in GPI anchor biosynthesis, somatic mutations or genetic variants of which have been associated with paroxysmal nocturnal hemoglobinuria (PNH), or PIGA deficiency, respectively. More than 10 PIGA pathogenic or likely pathogenic variants have been reported in a wide spectrum of clinical syndromes of PIGA deficiency, including multiple congenital anomalies hypotonia‐seizures syndrome 2 (MCAHS2). Methods Whole‐exome sequencing (WES) was performed on two trios, that is., the proband's family and his affected maternal cousin's family, from a nonconsanguineous Chinese family pedigree with hypotonia‐encephalopathy‐seizures disease history and putative X‐linked recessive inheritance. Sanger sequencing for PIGA variant was performed on affected members as well as unaffected members in the family pedigree to verify its familial segregation. Results A novel likely pathogenic variant in PIGA was identified through comparative WES analysis of the two affected families. The single‐nucleotide substitution (NC_000023.9:g.15343279T>C) is located in intron 3 of the PIGA gene and within the splice acceptor consensus sequence (NM_002641.3:c.849‐5A>G). Even though we have not performed RNA studies, in silico tools predict that this intronic variant may alter normal splicing, causing a four base pair insertion which creates a frameshift and a premature stop codon at position 297 (NP_002632.1:p.(Arg283Serfs*15)). Sanger sequencing analysis of the extended family members confirmed the presence of the variant and its X‐linked inheritance. Conclusion WES data analysis along with familial segregation of a rare intronic variant are suggestive of a diagnosis of X‐liked PIGA deficiency with clinical features of MCAHS2.
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Affiliation(s)
- Junli Yang
- Department of Pediatrics, Qilu Hospital of Shandong University, Jinan, China
| | - Qiong Wang
- Institute for Biology and Medicine, Wuhan University of Science and Technology, Wuhan, China
| | - Qingcui Zhuo
- Department of Pediatrics, Qilu Hospital of Shandong University, Jinan, China
| | - Huiling Tian
- Children Rehabilitation Center of Linyi Women and Children's Hospital, Linyi, China
| | - Wen Li
- Department of Pediatrics, Qilu Hospital of Shandong University, Jinan, China
| | - Fang Luo
- MyGenostics Inc., Beijing, China
| | - Jinghui Zhang
- Department of Pediatrics, Qilu Hospital of Shandong University, Jinan, China
| | - Dan Bi
- Department of Pediatrics, Qilu Hospital of Shandong University, Jinan, China
| | - Jing Peng
- Institute for Biology and Medicine, Wuhan University of Science and Technology, Wuhan, China
| | - Dong Zhou
- Department of Pediatrics, Qilu Hospital of Shandong University, Jinan, China
| | - Huawei Xin
- Institute for Biology and Medicine, Wuhan University of Science and Technology, Wuhan, China.,School of Pharmacy, Linyi University, Linyi, China
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17
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Abstract
Biallelic mutations in the post-GPI attachment to proteins 3 (PGAP3) gene cause hyperphosphatasia with mental retardation syndrome 4 (HPMRS4), which is characterized by elevated serum alkaline phosphatase, severe psychomotor developmental delay, seizures, and facial dysmorphism. To date, 15 PGAP3 mutations have been reported in humans. Here we report a novel homozygous PGAP3 mutation (c.314C>A, p.Pro105Gln) in a Croatian patient and fully describe the clinical features.
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18
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Altassan R, Fox S, Poulin C, Buhas D. Hyperphosphatasia with mental retardation syndrome, expanded phenotype of PIGL related disorders. Mol Genet Metab Rep 2018; 15:46-49. [PMID: 30023290 PMCID: PMC6047459 DOI: 10.1016/j.ymgmr.2018.01.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 01/26/2018] [Accepted: 01/26/2018] [Indexed: 12/20/2022] Open
Abstract
Hypomorphic mutations in six different genes involved in the glycosylphosphatidylinositol (GPI) biogenesis pathway are linked to Mabry syndrome (hyperphosphatasia with mental retardation syndrome, HPMRS). This report on the third affected family with a HPMRS phenotype caused by mutations in PIGL, confirming the seventh GPI biogenesis gene linked to HPMRS. Two siblings presented with the main features of HPMRS; developmental delay, cognitive impairment, seizure disorder, skeletal deformities, and high alkaline phosphatase. We identified two heterozygous mutations in the PIGL gene (P.Trp20Ter and p.Arg88Cys). PIGL mutations have been linked to another distinctive neuroectodermal disorder: CHIME syndrome. The clinical picture of our patients expands the spectrum of PIGL-related phenotypes.
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Key Words
- ALP, alkaline phosphatase
- CHIME syndrome
- CHIME, ocular colobomas, heart defect, ichthyosis, mental retardation, and abnormal ears or epilepsy
- CSS, Coffin-Siris syndrome
- GPI biogenesis
- GPI, glycosylphosphatidylinositol
- HPMRS, hyperphosphatasia with mental retardation syndrome
- Hyperphosphatasia mental retardation syndrome (HPMRS)
- Mabry syndrome
- PIGL gene
- PIGL, phosphatidylinositol glycan anchor biosynthesis class L
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Affiliation(s)
- Ruqaiah Altassan
- Department of Medical Genetics, Montreal Children's Hospital, McGill University Health Center, Montreal, Quebec, Canada
| | - Stephanie Fox
- Department of Medical Genetics, Montreal Children's Hospital, McGill University Health Center, Montreal, Quebec, Canada
| | - Chantal Poulin
- Department of Pediatric, Division of Neurology, Montreal Children's Hospital, McGill University Health Center, Montreal, Quebec, Canada
| | - Daniela Buhas
- Department of Medical Genetics, Montreal Children's Hospital, McGill University Health Center, Montreal, Quebec, Canada.,Department of Human Genetics, McGill University, Montreal, Quebec, Canada
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19
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Knaus A, Pantel JT, Pendziwiat M, Hajjir N, Zhao M, Hsieh TC, Schubach M, Gurovich Y, Fleischer N, Jäger M, Köhler S, Muhle H, Korff C, Møller RS, Bayat A, Calvas P, Chassaing N, Warren H, Skinner S, Louie R, Evers C, Bohn M, Christen HJ, van den Born M, Obersztyn E, Charzewska A, Endziniene M, Kortüm F, Brown N, Robinson PN, Schelhaas HJ, Weber Y, Helbig I, Mundlos S, Horn D, Krawitz PM. Characterization of glycosylphosphatidylinositol biosynthesis defects by clinical features, flow cytometry, and automated image analysis. Genome Med 2018; 10:3. [PMID: 29310717 PMCID: PMC5759841 DOI: 10.1186/s13073-017-0510-5] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Accepted: 12/11/2017] [Indexed: 12/17/2022] Open
Abstract
Background Glycosylphosphatidylinositol biosynthesis defects (GPIBDs) cause a group of phenotypically overlapping recessive syndromes with intellectual disability, for which pathogenic mutations have been described in 16 genes of the corresponding molecular pathway. An elevated serum activity of alkaline phosphatase (AP), a GPI-linked enzyme, has been used to assign GPIBDs to the phenotypic series of hyperphosphatasia with mental retardation syndrome (HPMRS) and to distinguish them from another subset of GPIBDs, termed multiple congenital anomalies hypotonia seizures syndrome (MCAHS). However, the increasing number of individuals with a GPIBD shows that hyperphosphatasia is a variable feature that is not ideal for a clinical classification. Methods We studied the discriminatory power of multiple GPI-linked substrates that were assessed by flow cytometry in blood cells and fibroblasts of 39 and 14 individuals with a GPIBD, respectively. On the phenotypic level, we evaluated the frequency of occurrence of clinical symptoms and analyzed the performance of computer-assisted image analysis of the facial gestalt in 91 individuals. Results We found that certain malformations such as Morbus Hirschsprung and diaphragmatic defects are more likely to be associated with particular gene defects (PIGV, PGAP3, PIGN). However, especially at the severe end of the clinical spectrum of HPMRS, there is a high phenotypic overlap with MCAHS. Elevation of AP has also been documented in some of the individuals with MCAHS, namely those with PIGA mutations. Although the impairment of GPI-linked substrates is supposed to play the key role in the pathophysiology of GPIBDs, we could not observe gene-specific profiles for flow cytometric markers or a correlation between their cell surface levels and the severity of the phenotype. In contrast, it was facial recognition software that achieved the highest accuracy in predicting the disease-causing gene in a GPIBD. Conclusions Due to the overlapping clinical spectrum of both HPMRS and MCAHS in the majority of affected individuals, the elevation of AP and the reduced surface levels of GPI-linked markers in both groups, a common classification as GPIBDs is recommended. The effectiveness of computer-assisted gestalt analysis for the correct gene inference in a GPIBD and probably beyond is remarkable and illustrates how the information contained in human faces is pivotal in the delineation of genetic entities. Electronic supplementary material The online version of this article (doi:10.1186/s13073-017-0510-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Alexej Knaus
- Institut für Medizinische Genetik und Humangenetik, Charité Universitätsmedizin Berlin, 13353, Berlin, Germany.,Max Planck Institute for Molecular Genetics, 14195, Berlin, Germany.,Berlin-Brandenburg School for Regenerative Therapies, Charité Universitätsmedizin Berlin, 13353, Berlin, Germany.,Institute for Genomic Statistics and Bioinformatics, University Hospital Bonn, Rheinische Friedrich-Wilhelms-Universität Bonn, 53127, Bonn, Germany
| | - Jean Tori Pantel
- Institut für Medizinische Genetik und Humangenetik, Charité Universitätsmedizin Berlin, 13353, Berlin, Germany
| | - Manuela Pendziwiat
- Department of Neuropediatrics, University Medical Center Schleswig Holstein, 24105, Kiel, Germany
| | - Nurulhuda Hajjir
- Institut für Medizinische Genetik und Humangenetik, Charité Universitätsmedizin Berlin, 13353, Berlin, Germany
| | - Max Zhao
- Institut für Medizinische Genetik und Humangenetik, Charité Universitätsmedizin Berlin, 13353, Berlin, Germany
| | - Tzung-Chien Hsieh
- Institut für Medizinische Genetik und Humangenetik, Charité Universitätsmedizin Berlin, 13353, Berlin, Germany.,Institute for Genomic Statistics and Bioinformatics, University Hospital Bonn, Rheinische Friedrich-Wilhelms-Universität Bonn, 53127, Bonn, Germany
| | - Max Schubach
- Institut für Medizinische Genetik und Humangenetik, Charité Universitätsmedizin Berlin, 13353, Berlin, Germany.,Berlin Institute of Health (BIH), 10178, Berlin, Germany
| | | | | | - Marten Jäger
- Institut für Medizinische Genetik und Humangenetik, Charité Universitätsmedizin Berlin, 13353, Berlin, Germany.,Berlin Institute of Health (BIH), 10178, Berlin, Germany
| | - Sebastian Köhler
- Institut für Medizinische Genetik und Humangenetik, Charité Universitätsmedizin Berlin, 13353, Berlin, Germany
| | - Hiltrud Muhle
- Department of Neuropediatrics, University Medical Center Schleswig Holstein, 24105, Kiel, Germany
| | - Christian Korff
- Unité de Neuropédiatrie, Université de Genève, CH-1211, Genève, Switzerland
| | - Rikke S Møller
- Danish Epilepsy Centre, DK-4293, Dianalund, Denmark.,Institute for Regional Health Services Research, University of Southern Denmark, DK-5000, Odense, Denmark
| | - Allan Bayat
- Department of Pediatrics, University Hospital of Hvidovre, 2650, Hvicovre, Denmark
| | - Patrick Calvas
- Service de Génétique Médicale, Hôpital Purpan, CHU, 31059, Toulouse, France
| | - Nicolas Chassaing
- Service de Génétique Médicale, Hôpital Purpan, CHU, 31059, Toulouse, France
| | | | | | | | - Christina Evers
- Genetische Poliklinik, Universitätsklinik Heidelberg, 69120, Heidelberg, Germany
| | - Marc Bohn
- St. Bernward Krankenhaus, 31134, Hildesheim, Germany
| | - Hans-Jürgen Christen
- Kinderkrankenhaus auf der Bult, Hannoversche Kinderheilanstalt, 30173, Hannover, Germany
| | | | - Ewa Obersztyn
- Institute of Mother and Child Department of Molecular Genetics, 01-211, Warsaw, Poland
| | - Agnieszka Charzewska
- Institute of Mother and Child Department of Molecular Genetics, 01-211, Warsaw, Poland
| | - Milda Endziniene
- Neurology Department, Lithuanian University of Health Sciences, 50009, Kaunas, Lithuania
| | - Fanny Kortüm
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany
| | - Natasha Brown
- Victorian Clinical Genetics Services, Royal Children's Hospital, MCRI, Parkville, Australia.,Department of Clinical Genetics, Austin Health, Heidelberg, Australia
| | - Peter N Robinson
- The Jackson Laboratory for Genomic Medicine, 06032, Farmington, USA
| | - Helenius J Schelhaas
- Departement of Neurology, Academic Center for Epileptology, 5590, Heeze, The Netherlands
| | - Yvonne Weber
- Department of Neurology and Epileptology and Hertie Institute for Clinical Brain Research, University Tübingen, 72076, Tübingen, Germany
| | - Ingo Helbig
- Institute for Genomic Statistics and Bioinformatics, University Hospital Bonn, Rheinische Friedrich-Wilhelms-Universität Bonn, 53127, Bonn, Germany.,Pediatric Neurology, Children's Hospital of Philadelphia, 3401, Philadelphia, USA
| | - Stefan Mundlos
- Institut für Medizinische Genetik und Humangenetik, Charité Universitätsmedizin Berlin, 13353, Berlin, Germany.,Max Planck Institute for Molecular Genetics, 14195, Berlin, Germany
| | - Denise Horn
- Institut für Medizinische Genetik und Humangenetik, Charité Universitätsmedizin Berlin, 13353, Berlin, Germany.
| | - Peter M Krawitz
- Institut für Medizinische Genetik und Humangenetik, Charité Universitätsmedizin Berlin, 13353, Berlin, Germany. .,Max Planck Institute for Molecular Genetics, 14195, Berlin, Germany. .,Institute for Genomic Statistics and Bioinformatics, University Hospital Bonn, Rheinische Friedrich-Wilhelms-Universität Bonn, 53127, Bonn, Germany.
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20
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Zehavi Y, von Renesse A, Daniel-Spiegel E, Sapir Y, Zalman L, Chervinsky I, Schuelke M, Straussberg R, Spiegel R. A homozygous PIGO mutation associated with severe infantile epileptic encephalopathy and corpus callosum hypoplasia, but normal alkaline phosphatase levels. Metab Brain Dis 2017; 32:2131-2137. [PMID: 28900819 DOI: 10.1007/s11011-017-0109-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2017] [Accepted: 09/06/2017] [Indexed: 01/20/2023]
Abstract
We describe two sisters from a consanguineous Arab family with global developmental delay, dystrophy, axial hypotonia, epileptic encephalopathy dominated by intractable complex partial seizures that were resistant to various anti-epileptic treatments. Dysmorphic features comprised low set ears, hypertelorism, upslanting palpebral fissures, a broad nasal bridge, and blue sclera with elongated eyelashes. Brain MRI in both children showed a corpus callosum hypoplasia that was evident already in utero and evolving cortical atrophy. Autozygosity mapping in combination with Whole Exome Sequencing revealed a homozygous missense mutation in the PIGO gene [c.765G > A, NM_032634.3] that affected a highly conserved methionine in the alkaline phosphatase-like core domain of the protein [p.(Met255Ile), NP_116023.2]. PIGO encodes the GPI-ethanolamine phosphate transferase 3, which is crucial for the final synthetic step of the glycosylphosphatidylinositol-anchor that attaches many enzymes to their cell surfaces, such as the alkaline phosphatase and granulocyte surface markers. Interestingly, measurement of serum alkaline phosphatase activities in both children was normal or only slightly elevated. Quantification of granulocyte surface antigens CD16/24/59 yielded reduced levels only for CD59. Phenotype analysis of our and other published patients with PIGO mutations reveals a more severe affectation and predominantly neurological presentation in individuals carrying a mutation in the alkaline phosphatase-like core domain thereby hinting towards a genotype-phenotype relation for PIGO gene mutations.
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Affiliation(s)
- Yoav Zehavi
- Pediatric Department B, Emek Medical Center, 1834111, Afula, Israel
| | - Anja von Renesse
- NeuroCure Clinical Research Center and Department of Neuropediatrics, Charité Universitätsmedizin, Berlin, Germany
| | - Etty Daniel-Spiegel
- Department of Obstetrics and Gynecology, Ultrasound Unit, Emek Medical Center, Afula, Israel
- Rappaport Faculty of Medicine, Technion, Haifa, Israel
| | - Yonatan Sapir
- Department of Radiology, Emek Medical Center, Afula, Israel
| | - Luci Zalman
- Hematology-Oncology Service, Emek Medical Center, Afula, Israel
| | | | - Markus Schuelke
- NeuroCure Clinical Research Center and Department of Neuropediatrics, Charité Universitätsmedizin, Berlin, Germany
| | - Rachel Straussberg
- Pediatric Neurology Unit, Schneider Children's Medical Center, Petach Tikva, Israel
| | - Ronen Spiegel
- Pediatric Department B, Emek Medical Center, 1834111, Afula, Israel.
- Rappaport Faculty of Medicine, Technion, Haifa, Israel.
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21
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Xue J, Chang X, Zhang Y, Yang Z. Novel phenotypes of pyridox(am)ine-5'-phosphate oxidase deficiency and high prevalence of c.445_448del mutation in Chinese patients. Metab Brain Dis 2017; 32:1081-1087. [PMID: 28349276 DOI: 10.1007/s11011-017-9995-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2016] [Accepted: 03/13/2017] [Indexed: 01/11/2023]
Abstract
To analyze the clinical and genetic characteristics of Chinese patients with pyridox(am)ine-5'-phosphate oxidase (PNPO) deficiency. The clinical presentations and the responses to treatments were analyzed in 4 patients. Blood and urinary metabolic screenings, electroencephalogram (EEG), brain magnetic resonance imaging (MRI) and epilepsy-related genes detection were performed in all patients. Patient 1 and 2 were identical twin brothers, who were born at 35+5 w gestation with a sign of encephalopathy. Their seizures started within the first day and could not be controlled by pyridoxine or pyridoxal-5'-phosphate (PLP) completely. Patient 3 presented seizures at 5 months, responding well to pyridoxine. Seizures in patient 4 began at 40 days after birth and were controlled by valproic acid and topiramate. EEG showed atypical hypsarrhythmia or multifocal epileptiform discharges in 3 patients, and showed normality in patient 4. MRI showed nonspecific abnormality or normality. Blood metabolic screening showed multiple amino acids level abnormalities in all cases. Urinary metabolic screening showed vanillactic acid prominently elevated in 3 patients. Genetic analysis revealed 5 mutations of PNPO, three of which were novel. The mutation c.445_448del was carried by the twins and patient 3. Assessment of psychomotor development indicated severe delay in 3 patients and borderline to mild delay in patient 3. This is the first time to report patients with PNPO deficiency diagnosed by gene analysis in China. The novel clinical characteristics and novel mutations found here expanded the phenotypes and genotypes of this disease. Further, the frameshift mutation c.445_448del might be high prevalence in PNPO deficiency in Chinese patients.
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Affiliation(s)
- Jiao Xue
- Department of Pediatrics, Peking University First Hospital, No.1, Xi'anmen Street, Xicheng District, Beijing, 100034, China
| | - Xingzhi Chang
- Department of Pediatrics, Peking University First Hospital, No.1, Xi'anmen Street, Xicheng District, Beijing, 100034, China
| | - Yuehua Zhang
- Department of Pediatrics, Peking University First Hospital, No.1, Xi'anmen Street, Xicheng District, Beijing, 100034, China.
| | - Zhixian Yang
- Department of Pediatrics, Peking University First Hospital, No.1, Xi'anmen Street, Xicheng District, Beijing, 100034, China.
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22
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PIGO deficiency: palmoplantar keratoderma and novel mutations. Orphanet J Rare Dis 2017; 12:101. [PMID: 28545593 PMCID: PMC5445308 DOI: 10.1186/s13023-017-0654-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2016] [Accepted: 05/15/2017] [Indexed: 01/19/2023] Open
Abstract
Background Several genetic defects have been identified in the glycosylphosphatidylinositol (GPI) anchor synthesis, including mutations in PIGO encoding phosphatidylinositol glycan anchor biosynthesis class O protein. These defects constitute a subgroup of the congenital disorders of glycosylation (CDG). Seven patients from five families have been reported carrying variants in PIGO that cause an autosomal recessive syndrome characterised by dysmorphism, psychomotor disability, epilepsy and hyperphosphatasemia. Methods Whole exome sequencing was performed in a boy with dysmorphism, psychomotor disability, epilepsy, palmoplantar keratoderma, hyperphosphatasemia and platelet dysfunction without a clinical bleeding phenotype. Results Two novel variants in PIGO were detected. The missense variant encoding p. His871Pro was inherited from the boy’s father while the frameshift variant encoding p. Arg604ProfsTer40 was maternally inherited. Conclusion A boy with two novel PIGO variants is reported. The skin phenotype and platelet dysfunction in this patient have not been described in previously reported patients with PIGO deficiency but it is of course uncertain whether these are caused by this disorder. The literature on PIGO deficiency is reviewed. Electronic supplementary material The online version of this article (doi:10.1186/s13023-017-0654-9) contains supplementary material, which is available to authorized users.
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23
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Tanigawa J, Mimatsu H, Mizuno S, Okamoto N, Fukushi D, Tominaga K, Kidokoro H, Muramatsu Y, Nishi E, Nakamura S, Motooka D, Nomura N, Hayasaka K, Niihori T, Aoki Y, Nabatame S, Hayakawa M, Natsume J, Ozono K, Kinoshita T, Wakamatsu N, Murakami Y. Phenotype-genotype correlations of PIGO deficiency with variable phenotypes from infantile lethality to mild learning difficulties. Hum Mutat 2017; 38:805-815. [PMID: 28337824 DOI: 10.1002/humu.23219] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Revised: 03/15/2017] [Accepted: 03/19/2017] [Indexed: 01/23/2023]
Abstract
Inherited GPI (glycosylphosphatidylinositol) deficiencies (IGDs), a recently defined group of diseases, show a broad spectrum of symptoms. Hyperphosphatasia mental retardation syndrome, also known as Mabry syndrome, is a type of IGDs. There are at least 26 genes involved in the biosynthesis and transport of GPI-anchored proteins; however, IGDs constitute a rare group of diseases, and correlations between the spectrum of symptoms and affected genes or the type of mutations have not been shown. Here, we report four newly identified and five previously described Japanese families with PIGO (phosphatidylinositol glycan anchor biosynthesis class O) deficiency. We show how the clinical severity of IGDs correlates with flow cytometric analysis of blood, functional analysis using a PIGO-deficient cell line, and the degree of hyperphosphatasia. The flow cytometric analysis and hyperphosphatasia are useful for IGD diagnosis, but the expression level of GPI-anchored proteins and the degree of hyperphosphatasia do not correlate, although functional studies do, with clinical severity. Compared with PIGA (phosphatidylinositol glycan anchor biosynthesis class A) deficiency, PIGO deficiency shows characteristic features, such as Hirschsprung disease, brachytelephalangy, and hyperphosphatasia. This report shows the precise spectrum of symptoms according to the severity of mutations and compares symptoms between different types of IGD.
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Affiliation(s)
- Junpei Tanigawa
- Department of Pediatrics, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan
| | - Haruka Mimatsu
- Division of Neonatology Center for Maternal-Neonatal Care, Nagoya University Hospital, Nagoya, Aichi, Japan
| | - Seiji Mizuno
- Department of Pediatrics, Central Hospital, Aichi Human Service Center, Kasugai, Aichi, Japan
| | - Nobuhiko Okamoto
- Department of Medical Genetics, Osaka Medical Center and Research Institute for Maternal and Child Health, Izumi, Osaka, Japan
| | - Daisuke Fukushi
- Department of Genetics, Institute for Developmental Research, Aichi Human Service Center, Kasugai, Aichi, Japan
| | - Koji Tominaga
- Department of Pediatrics, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan.,Department of Child Development, United Graduate School of Child Development, Osaka University, Suita, Osaka, Japan
| | - Hiroyuki Kidokoro
- Department of Pediatrics, Nagoya University Hospital, Nagoya, Aichi, Japan
| | - Yukako Muramatsu
- Division of Neonatology Center for Maternal-Neonatal Care, Nagoya University Hospital, Nagoya, Aichi, Japan
| | - Eriko Nishi
- Department of Pediatrics, Central Hospital, Aichi Human Service Center, Kasugai, Aichi, Japan
| | - Shota Nakamura
- Department of Infection Metagenomics, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan
| | - Daisuke Motooka
- Department of Infection Metagenomics, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan
| | - Noriko Nomura
- Department of Genetics, Institute for Developmental Research, Aichi Human Service Center, Kasugai, Aichi, Japan
| | - Kiyoshi Hayasaka
- Department of Pediatrics, Yamagata University School of Medicine, Yamagata, Yamagata, Japan
| | - Tetsuya Niihori
- Department of Medical Genetics, Tohoku University School of Medicine, Sendai, Miyagi, Japan
| | - Yoko Aoki
- Department of Medical Genetics, Tohoku University School of Medicine, Sendai, Miyagi, Japan
| | - Shin Nabatame
- Department of Pediatrics, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan
| | - Masahiro Hayakawa
- Division of Neonatology Center for Maternal-Neonatal Care, Nagoya University Hospital, Nagoya, Aichi, Japan
| | - Jun Natsume
- Department of Developmental Disability Medicine and Department of Pediatrics, Nagoya University Graduate School of Medicine, Nagoya, Aichi, Japan
| | - Keiichi Ozono
- Department of Pediatrics, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan
| | - Taroh Kinoshita
- Department of Immunoregulation, Research Institute for Microbial Diseases Osaka University, Suita, Osaka, Japan
| | - Nobuaki Wakamatsu
- Department of Genetics, Institute for Developmental Research, Aichi Human Service Center, Kasugai, Aichi, Japan
| | - Yoshiko Murakami
- Department of Immunoregulation, Research Institute for Microbial Diseases Osaka University, Suita, Osaka, Japan
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24
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Johnstone DL, Nguyen TTM, Murakami Y, Kernohan KD, Tétreault M, Goldsmith C, Doja A, Wagner JD, Huang L, Hartley T, St-Denis A, le Deist F, Majewski J, Bulman DE, Kinoshita T, Dyment DA, Boycott KM, Campeau PM. Compound heterozygous mutations in the gene PIGP are associated with early infantile epileptic encephalopathy. Hum Mol Genet 2017; 26:1706-1715. [DOI: 10.1093/hmg/ddx077] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Accepted: 02/27/2017] [Indexed: 12/27/2022] Open
Affiliation(s)
- Devon L. Johnstone
- Children’s Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Ontario K1H8L1, Canada
| | - Thi-Tuyet-Mai Nguyen
- Research Center, CHU Sainte-Justine, University of Montreal, Montreal, Quebec H3T1C5, Canada
| | - Yoshiko Murakami
- WPI Immunology Frontier Research Center and Research Institute for Microbial Diseases, Osaka University, Osaka 565-0871, Japan
| | - Kristin D. Kernohan
- Children’s Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Ontario K1H8L1, Canada
| | - Martine Tétreault
- Department of Human Genetics, McGill University, Montreal, Quebec H3A1B1, Canada
- McGill University and Genome Quebec Innovation Centre, Montreal, Quebec H3A0G1, Canada
| | - Claire Goldsmith
- Department of Genetics, Children’s Hospital of Eastern Ontario, Ottawa, Ontario K1H8L1, Canada
| | - Asif Doja
- Division of Neurology, Department of Pediatrics, Children’s Hospital of Eastern Ontario, Ottawa, Ontario K1H8L1, Canada
| | - Justin D. Wagner
- Children’s Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Ontario K1H8L1, Canada
| | - Lijia Huang
- Children’s Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Ontario K1H8L1, Canada
| | - Taila Hartley
- Children’s Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Ontario K1H8L1, Canada
| | - Anik St-Denis
- Research Center, CHU Sainte-Justine, University of Montreal, Montreal, Quebec H3T1C5, Canada
| | - Françoise le Deist
- Research Center, CHU Sainte-Justine, University of Montreal, Montreal, Quebec H3T1C5, Canada
| | - Jacek Majewski
- Department of Human Genetics, McGill University, Montreal, Quebec H3A1B1, Canada
- McGill University and Genome Quebec Innovation Centre, Montreal, Quebec H3A0G1, Canada
| | - Dennis E. Bulman
- Children’s Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Ontario K1H8L1, Canada
| | - Taroh Kinoshita
- WPI Immunology Frontier Research Center and Research Institute for Microbial Diseases, Osaka University, Osaka 565-0871, Japan
| | - David A. Dyment
- Children’s Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Ontario K1H8L1, Canada
- Department of Genetics, Children’s Hospital of Eastern Ontario, Ottawa, Ontario K1H8L1, Canada
| | - Kym M. Boycott
- Children’s Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Ontario K1H8L1, Canada
- Department of Genetics, Children’s Hospital of Eastern Ontario, Ottawa, Ontario K1H8L1, Canada
| | - Philippe M. Campeau
- Research Center, CHU Sainte-Justine, University of Montreal, Montreal, Quebec H3T1C5, Canada
- Department of Pediatrics, Sainte-Justine Hospital, University of Montreal, Montreal, Quebec H3T1C5, Canada
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