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Hebbar M, Al-Taweel N, Gill I, Boelman C, Dean RA, Goodchild SJ, Mezeyova J, Shuart NG, Johnson JP, Lee J, Michoulas A, Huh LL, Armstrong L, Connolly MB, Demos MK. Expanding the genotype-phenotype spectrum in SCN8A-related disorders. BMC Neurol 2024; 24:31. [PMID: 38233770 PMCID: PMC10792783 DOI: 10.1186/s12883-023-03478-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 11/27/2023] [Indexed: 01/19/2024] Open
Abstract
BACKGROUND SCN8A-related disorders are a group of variable conditions caused by pathogenic variations in SCN8A. Online Mendelian Inheritance in Man (OMIM) terms them as developmental and epileptic encephalopathy 13, benign familial infantile seizures 5 or cognitive impairment with or without cerebellar ataxia. METHODS In this study, we describe clinical and genetic results on eight individuals from six families with SCN8A pathogenic variants identified via exome sequencing. RESULTS Clinical findings ranged from normal development with well-controlled epilepsy to significant developmental delay with treatment-resistant epilepsy. Three novel and three reported variants were observed in SCN8A. Electrophysiological analysis in transfected cells revealed a loss-of-function variant in Patient 4. CONCLUSIONS This work expands the clinical and genotypic spectrum of SCN8A-related disorders and provides electrophysiological results on a novel loss-of-function SCN8A variant.
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Affiliation(s)
- Malavika Hebbar
- Division of Neurology, Department of Pediatrics, BC Children's Hospital, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Nawaf Al-Taweel
- Division of Neurology, Department of Pediatrics, BC Children's Hospital, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Inderpal Gill
- Division of Neurology, Department of Pediatrics, BC Children's Hospital, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Cyrus Boelman
- Division of Neurology, Department of Pediatrics, BC Children's Hospital, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Richard A Dean
- Xenon Pharmaceuticals, 200-3650 Gilmore Way, Burnaby, BC, V5G 4W8, Canada
| | - Samuel J Goodchild
- Xenon Pharmaceuticals, 200-3650 Gilmore Way, Burnaby, BC, V5G 4W8, Canada
| | - Janette Mezeyova
- Xenon Pharmaceuticals, 200-3650 Gilmore Way, Burnaby, BC, V5G 4W8, Canada
| | | | - J P Johnson
- Xenon Pharmaceuticals, 200-3650 Gilmore Way, Burnaby, BC, V5G 4W8, Canada
| | - James Lee
- Division of Neurology, Department of Pediatrics, BC Children's Hospital, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Aspasia Michoulas
- Division of Neurology, Department of Pediatrics, BC Children's Hospital, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Linda L Huh
- Division of Neurology, Department of Pediatrics, BC Children's Hospital, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Linlea Armstrong
- Department of Medical Genetics, BC Children's Hospital, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Mary B Connolly
- Division of Neurology, Department of Pediatrics, BC Children's Hospital, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Michelle K Demos
- Division of Neurology, Department of Pediatrics, BC Children's Hospital, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada.
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Hebbar M, Al-Taweel N, Gill I, Boelman C, Dean RA, Goodchild SJ, Mezeyova J, Shuart NG, Johnson JP, Lee J, Michoulas A, Huh LL, Armstrong L, Connolly MB, Demos MK. Expanding the genotype-phenotype spectrum in SCN8A-related disorders. Res Sq 2023:rs.3.rs-3221902. [PMID: 37609289 PMCID: PMC10441468 DOI: 10.21203/rs.3.rs-3221902/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/24/2023]
Abstract
Background SCN8A-related disorders are a group of variable conditions caused by pathogenic variations in SCN8A. Online Mendelian Inheritance in Man (OMIM) terms them as developmental and epileptic encephalopathy 13, benign familial infantile seizures 5 or cognitive impairment with or without cerebellar ataxia. Methods In this study, we describe clinical and genetic results on eight individuals from six families with SCN8A pathogenic variants identified via exome sequencing. Results Clinical findings ranged from normal development with well-controlled epilepsy to significant developmental delay with treatment-resistant epilepsy. Three novel and three reported variants were observed in SCN8A. Electrophysiological analysis in transfected cells revealed a loss-of-function variant in Patient 4. Conclusions This work expands the clinical and genotypic spectrum of SCN8A-related disorders and provides electrophysiological results on a novel loss-of-function SCN8A variant.
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Affiliation(s)
- Malavika Hebbar
- Division of Neurology, Department of Pediatrics, BC Children's Hospital, Faculty of Medicine, University of British Columbia, Vancouver BC
| | - Nawaf Al-Taweel
- Division of Neurology, Department of Pediatrics, BC Children's Hospital, Faculty of Medicine, University of British Columbia, Vancouver BC
| | - Inderpal Gill
- Division of Neurology, Department of Pediatrics, BC Children's Hospital, Faculty of Medicine, University of British Columbia, Vancouver BC
| | - Cyrus Boelman
- Division of Neurology, Department of Pediatrics, BC Children's Hospital, Faculty of Medicine, University of British Columbia, Vancouver BC
| | - Richard A Dean
- Xenon Pharmaceuticals, 200-3650 Gilmore Way, Burnaby, BC V5G 4W8
| | | | - Janette Mezeyova
- Xenon Pharmaceuticals, 200-3650 Gilmore Way, Burnaby, BC V5G 4W8
| | | | - J P Johnson
- Xenon Pharmaceuticals, 200-3650 Gilmore Way, Burnaby, BC V5G 4W8
| | - James Lee
- Division of Neurology, Department of Pediatrics, BC Children's Hospital, Faculty of Medicine, University of British Columbia, Vancouver BC
| | - Aspasia Michoulas
- Division of Neurology, Department of Pediatrics, BC Children's Hospital, Faculty of Medicine, University of British Columbia, Vancouver BC
| | - Linda L Huh
- Division of Neurology, Department of Pediatrics, BC Children's Hospital, Faculty of Medicine, University of British Columbia, Vancouver BC
| | - Linlea Armstrong
- Department of Medical Genetics, BC Children's Hospital, Faculty of Medicine, University of British Columbia, Vancouver BC
| | - Mary B Connolly
- Division of Neurology, Department of Pediatrics, BC Children's Hospital, Faculty of Medicine, University of British Columbia, Vancouver BC
| | - Michelle K Demos
- Division of Neurology, Department of Pediatrics, BC Children's Hospital, Faculty of Medicine, University of British Columbia, Vancouver BC
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Cook CB, Armstrong L, Boerkoel CF, Clarke LA, du Souich C, Demos MK, Gibson WT, Gill H, Lopez E, Patel MS, Selby K, Abu-Sharar Z, Elliott AM, Friedman JM. Somatic mosaicism detected by genome-wide sequencing in 500 parent-child trios with suspected genetic disease: clinical and genetic counseling implications. Cold Spring Harb Mol Case Stud 2021; 7:mcs.a006125. [PMID: 34697084 PMCID: PMC8751411 DOI: 10.1101/mcs.a006125] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 10/13/2021] [Indexed: 01/28/2023] Open
Abstract
Identifying genetic mosaicism is important in establishing a diagnosis, assessing recurrence risk, and providing accurate genetic counseling. Next-generation sequencing has allowed for the identification of mosaicism at levels below those detectable by conventional Sanger sequencing or chromosomal microarray analysis. The CAUSES Clinic was a pediatric translational trio-based genome-wide (exome or genome) sequencing study of 500 families (531 children) with suspected genetic disease at BC Children's and Women's Hospitals. Here we present 12 cases of apparent mosaicism identified in the CAUSES cohort: nine cases of parental mosaicism for a disease-causing variant found in a child and three cases of mosaicism in the proband for a de novo variant. In six of these cases, there was no evidence of mosaicism on Sanger sequencing—the variant was not detected on Sanger sequencing in three cases, and it appeared to be heterozygous in three others. These cases are examples of six clinical manifestations of mosaicism: a proband with classical clinical features of mosaicism (e.g., segmental abnormalities of skin pigmentation or asymmetrical growth of bilateral body parts), a proband with unusually mild manifestations of a disease, a mosaic proband who is clinically indistinguishable from the constitutive phenotype, a mosaic parent with no clinical features of the disease, a mosaic parent with mild manifestations of the disease, and a family in which both parents are unaffected and two siblings have the same disease-causing constitutional mutation. Our data demonstrate the importance of considering the possibility of mosaicism whenever exome or genome sequencing is performed and that its detection via genome-wide sequencing can permit more accurate genetic counseling.
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Affiliation(s)
- Courtney B Cook
- Department of Medical Genetics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada V6H 3N1
| | - Linlea Armstrong
- Department of Medical Genetics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada V6H 3N1.,BC Children's Hospital Research Institute, Vancouver, British Columbia, Canada V5Z 4H4
| | - Cornelius F Boerkoel
- Department of Medical Genetics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada V6H 3N1
| | - Lorne A Clarke
- Department of Medical Genetics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada V6H 3N1
| | - Christèle du Souich
- Department of Medical Genetics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada V6H 3N1.,BC Children's Hospital Research Institute, Vancouver, British Columbia, Canada V5Z 4H4
| | - Michelle K Demos
- Division of Neurology, Department of Pediatrics, BC Children's Hospital, Vancouver, British Columbia, Canada V6H 0B3
| | - William T Gibson
- Department of Medical Genetics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada V6H 3N1.,BC Children's Hospital Research Institute, Vancouver, British Columbia, Canada V5Z 4H4
| | - Harinder Gill
- Department of Medical Genetics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada V6H 3N1
| | - Elena Lopez
- Department of Medical Genetics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada V6H 3N1
| | - Millan S Patel
- Department of Medical Genetics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada V6H 3N1
| | - Kathryn Selby
- Division of Neurology, Department of Pediatrics, BC Children's Hospital, Vancouver, British Columbia, Canada V6H 0B3
| | - Ziad Abu-Sharar
- Division of Neurology, Department of Pediatrics, BC Children's Hospital, Vancouver, British Columbia, Canada V6H 0B3
| | | | - Alison M Elliott
- Department of Medical Genetics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada V6H 3N1.,BC Children's Hospital Research Institute, Vancouver, British Columbia, Canada V5Z 4H4.,Women's Health Research Institute, Vancouver, British Columbia, Canada V6H 2N9
| | - Jan M Friedman
- Department of Medical Genetics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada V6H 3N1.,BC Children's Hospital Research Institute, Vancouver, British Columbia, Canada V5Z 4H4
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Adam S, Birch PH, Coe RR, Bansback N, Jones AL, Connolly MB, Demos MK, Toyota EB, Farrer MJ, Friedman JM. Assessing an Interactive Online Tool to Support Parents' Genomic Testing Decisions. J Genet Couns 2018; 28:10.1007/s10897-018-0281-1. [PMID: 30033481 DOI: 10.1007/s10897-018-0281-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Accepted: 07/13/2018] [Indexed: 01/22/2023]
Abstract
Clinical use of genome-wide sequencing (GWS) requires pre-test genetic counseling, but the availability of genetic counseling is limited. We developed an interactive online decision-support tool, DECIDE, to make genetic counseling, patient education, and decision support more readily available. We performed a non-inferiority trial comparing DECIDE to standard genetic counseling to assess the clinical value of DECIDE for pre-GWS counseling. One hundred and six parents considering GWS for their children with epilepsy were randomized to conventional genetic counseling or DECIDE. Following the intervention, we measured parents' knowledge and empowerment and asked their opinions about using DECIDE. Both DECIDE and conventional genetic counseling significantly increased parents' knowledge, with no difference between groups. Empowerment also increased but by less than 2% in each group. Parents liked using DECIDE and found it useful; 81% would recommend it to others; 49% wished to use it along with a genetic counselor; 26% of parents preferred to see a genetic counselor; 7% preferred DECIDE alone; and 18% had no preference. DECIDE appears equivalent to genetic counseling at conveying information. In addition, it was highly acceptable to the majority of study participants, many of whom indicated that it was useful to their decision-making. Use of DECIDE as a pre-test tool may extend genetic counseling resources.
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Affiliation(s)
- Shelin Adam
- Department of Medical Genetics, University of British Columbia, Box 153, 4500 Oak Street, Vancouver, BC, V6H 3N1, Canada
| | - Patricia H Birch
- Department of Medical Genetics, University of British Columbia, Box 153, 4500 Oak Street, Vancouver, BC, V6H 3N1, Canada.
| | - Rachel R Coe
- Department of Medical Genetics, University of British Columbia, Box 153, 4500 Oak Street, Vancouver, BC, V6H 3N1, Canada
| | - Nick Bansback
- School of Population and Public Health, University of British Columbia, Vancouver, Canada
| | - Adrian L Jones
- Department of Statistics, University of British Columbia, Vancouver, Canada
| | - Mary B Connolly
- Department of Neurology, University of British Columbia, Vancouver, Canada
| | - Michelle K Demos
- Department of Neurology, University of British Columbia, Vancouver, Canada
| | - Eric B Toyota
- Department of Neurology, University of British Columbia, Vancouver, Canada
| | - Matthew J Farrer
- Centre for Applied Neurogenetics (CAN), Djavad Mowafaghian Centre, Department of Medical Genetics, University of British Columbia, Vancouver, Canada
| | - Jan M Friedman
- Department of Medical Genetics, University of British Columbia, Box 153, 4500 Oak Street, Vancouver, BC, V6H 3N1, Canada
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Buerki SE, Slade E, Schlade-Bartusiak K, Brown L, Rajcan-Separovic E, Eydoux P, Connolly MB, Demos MK. MG-127 Diagnostic accuracy of chromosome microarray in children with epilepsy and neurological abnormalities of unknown aetiology. J Med Genet 2015. [DOI: 10.1136/jmedgenet-2015-103577.18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Demos MK, van Karnebeek CD, Ross CJ, Adam S, Shen Y, Zhan SH, Shyr C, Horvath G, Suri M, Fryer A, Jones SJ, Friedman JM. A novel recurrent mutation in ATP1A3 causes CAPOS syndrome. Orphanet J Rare Dis 2014; 9:15. [PMID: 24468074 PMCID: PMC3937150 DOI: 10.1186/1750-1172-9-15] [Citation(s) in RCA: 134] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Accepted: 01/16/2014] [Indexed: 11/10/2022] Open
Abstract
Background We undertook genetic analysis of three affected families to identify the cause of dominantly-inherited CAPOS (cerebellar ataxia, areflexia, pes cavus, optic atrophy and sensorineural hearing loss) syndrome. Methods We used whole-exome sequencing to analyze two families affected with CAPOS syndrome, including the original family reported in 1996, and Sanger sequencing to assess familial segregation of rare variants identified in the probands and in a third, apparently unrelated family with CAPOS syndrome. Results We found an identical heterozygous missense mutation, c.2452G > A (p.(Glu818Lys)), in the Na+/K+ ATPase α3(ATP1A3) gene in the proband and his affected sister and mother, but not in either unaffected maternal grandparent, in the first family. The same mutation was also identified in the proband and three other affected members of the second family and in all three affected members of the third family. This mutation was not found in more than 3600 chromosomes from unaffected individuals. Conclusion Other mutations in ATP1A3 have previously been demonstrated to cause rapid-onset dystonia-parkinsonism (also called dystonia-12) or alternating hemiplegia of childhood. This study shows that an allelic mutation in ATP1A3 produces CAPOS syndrome.
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Affiliation(s)
- Michelle K Demos
- Division of Neurology, Department of Pediatrics, University of British Columbia and BC Children's Hospital, Vancouver, BC V6H 3N1, Canada.
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du Souich C, Chou A, Yin J, Oh T, Nelson TN, Hurlburt J, Arbour L, Friedlander R, McGillivray BC, Tyshchenko N, Rump A, Poskitt KJ, Demos MK, Van Allen MI, Boerkoel CF. Characterization of a new X-linked mental retardation syndrome with microcephaly, cortical malformation, and thin habitus. Am J Med Genet A 2010; 149A:2469-78. [PMID: 19842190 DOI: 10.1002/ajmg.a.33071] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
X-linked mental retardation (XLMR) affects 1-2/1,000 males and accounts for approximately 10% of all mental retardation (MR). We have ascertained a syndromic form of XLMR segregating within a five-generation family with seven affected males. Prominent characteristics include mild to severe MR, cortical malformation, microcephaly, seizures, thin build with distinct facial features including a long and thin face, epicanthic folds, almond-shaped eyes, upslanting palpebral fissures and micrognathia and behavioral problems. Carrier females have normal physical appearance and intelligence. This combination of features is unreported and distinct from Lujan-Fryns syndrome, Snyder-Robinson syndrome, and zinc finger DHHC domain-containing 9-associated MR. We propose the name of this new syndrome to be CK syndrome.
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Abstract
Pathogenic variations of the ARX (aristaless-related homeobox) gene are associated with marked phenotypic pleiotropy. These phenotypes are X-linked neurological disorders that include brain and genital malformation and non-malformation syndromes. Typically, malformation phenotypes result from pathogenic variations that are predicted to truncate the ARX protein, or alter residues in the highly conserved homeodomain. While non-malformation phenotypes tend to be caused by pathogenic variations that are predicted to expand the first two polyalanine tracts of ARX, or alter residues outside of the homeodomain. The most common pathogenic variation of the ARX gene is a duplication of 24 bp, c.429_452 dup, which leads to an expansion of the second polyalanine tract of the ARX protein from 12 to 20 alanine residues. This pathogenic variation is associated with both sporadic and familial nonsyndromic mental retardation. Syndromic manifestations include mental retardation with hand dystonia (Partington syndrome), infantile spasms (West syndrome) and/or other epileptic seizures. Here, we report on a novel pathogenic variant of a tandem 33 bp duplication that is predicted to result in an expansion of polyalanine tract 2 in two brothers with mental retardation, epilepsy, dystonia, and the novel feature of intermittent hyperventilation. This pathogenic variation is predicted to result in a "non-homogeneous" polyalanine tract expansion that is longer than predicted expansion caused by the common 24 bp duplication. The location of the novel 33 bp duplication in the same region as the common 24 bp duplication supports this region as the ARX variation "hot spot."
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Affiliation(s)
- Michelle K Demos
- Department of Pediatric Neurology, British Columbia's Children's Hospital, University of British Columbia, Vancouver, Canada.
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Demos MK, Macri V, Farrell K, Nelson TN, Chapman K, Accili E, Armstrong L. A novel KCNA1 mutation associated with global delay and persistent cerebellar dysfunction. Mov Disord 2009; 24:778-82. [PMID: 19205071 DOI: 10.1002/mds.22467] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Episodic Ataxia Type 1 is an autosomal dominant disorder characterized by episodes of ataxia and myokymia. It is associated with mutations in the KCNA1 voltage-gated potassium channel gene. In the present study, we describe a family with novel clinical features including persistent cerebellar dysfunction, cerebellar atrophy, and cognitive delay. All affected family members have myokymia and epilepsy, but only one individual has episodes of vertigo. Additional features include postural abnormalities, episodic stiffness and weakness. A novel KCNA1 mutation (c.1222G>T) which replaces a highly conserved valine with leucine at position 408 (p.Val408Leu) was identified in affected family members, and was found to augment the ability of the channel to inactivate. Together, our data suggests that KCNA1 mutations are associated with a broader clinical phenotype, which may include persistent cerebellar dysfunction and cognitive delay.
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Affiliation(s)
- Michelle K Demos
- Department of Pediatric Neurology, British Columbia's Children's Hospital, Vancouver, British Columbia, Canada.
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Demos MK, Waters PJ, Vallance HD, Lillquist Y, Makhseed N, Hyland K, Blau N, Connolly MB. 6-pyruvoyl-tetrahydropterin synthase deficiency with mild hyperphenylalaninemia. Ann Neurol 2005; 58:164-7. [PMID: 15984017 DOI: 10.1002/ana.20532] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Severe 6-pyruvoyl-tetrahydrobiopterin synthase deficiency is a tetrahydrobiopterin deficiency disorder that presents in infancy with developmental delay, seizures, and abnormal movements associated with hyperphenylalaninemia usually detectable by neonatal phenylketonuria screening programs. We describe an 8-year-old girl with delay, seizures, and dystonia with mild hyperphenylalaninemia detected in late childhood. The diagnosis of 6-pyruvoyl-tetrahydrobiopterin synthase deficiency was made by analysis of pterins in urine, pterins and neurotransmitters in cerebrospinal fluid, and enzyme assay. The patient improved clinically taking oral tetrahydrobiopterin, levodopa/carbidopa, and 5-hydroxytryptophan. This treatable condition may not always be detected by routine population screening for hyperphenylalaninemia.
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Affiliation(s)
- Michelle K Demos
- Department of Medical Genetics, University of British Columbia, Children's and Women's Health Centre of British Columbia, Vancouver, Canada.
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