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Garcia-Llorens G, Lopez-Navarro S, Jaijo T, Castell JV, Bort R. Modeling a Novel Variant of Glycogenosis IXa Using a Clonal Inducible Reprogramming System to Generate "Diseased" Hepatocytes for Accurate Diagnosis. J Pers Med 2022; 12:jpm12071111. [PMID: 35887608 PMCID: PMC9322025 DOI: 10.3390/jpm12071111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 07/01/2022] [Accepted: 07/05/2022] [Indexed: 11/16/2022] Open
Abstract
The diagnosis of inherited metabolic disorders is a long and tedious process. The matching of clinical data with a genomic variant in a specific metabolic pathway is an essential step, but the link between a genome and the clinical data is normally difficult, primarily for new missense variants or alterations in intron sequences. Notwithstanding, elucidation of the pathogenicity of a specific variant might be critical for an accurate diagnosis. In this study, we described a novel intronic variant c.2597 + 5G > T in the donor splice sequence of the PHKA2 gene. To investigate PHKA2 mRNA splicing, as well as the functional consequences on glycogen metabolism, we generated hepatocyte-like cells from a proband’s fibroblasts by direct reprogramming. We demonstrated an aberrant splicing of PHKA2, resulting in the incorporation of a 27 bp upstream of intron 23 into exon 23, which leads to an immediate premature STOP codon. The truncated protein was unable to phosphorylate the PYGL protein, causing a 4-fold increase in the accumulation of glycogen in hepatocyte-like cells. Collectively, the generation of personalized hepatocyte-like cells enabled an unequivocal molecular diagnosis and qualified the sister’s proband, a carrier of the same mutation, as a candidate for a preimplantation genetic diagnosis. Additionally, our direct reprogramming strategy allows for an unlimited source of “diseased” hepatocyte-like cells compatible with high-throughput platforms.
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Affiliation(s)
- Guillem Garcia-Llorens
- Unidad de Hepatología Experimental y Trasplante Hepático, Instituto de Investigación Sanitaria La Fe, Hospital Universitario y Politecnico La Fe, 46026 Valencia, Spain; (G.G.-L.); (S.L.-N.); (J.V.C.)
- Biochemistry and Molecular Biology Department, Universidad de Valencia, 46026 Valencia, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Sergi Lopez-Navarro
- Unidad de Hepatología Experimental y Trasplante Hepático, Instituto de Investigación Sanitaria La Fe, Hospital Universitario y Politecnico La Fe, 46026 Valencia, Spain; (G.G.-L.); (S.L.-N.); (J.V.C.)
| | - Teresa Jaijo
- Molecular, Cellular and Genomic Biomedicine, Instituto de Investigación Sanitaria La Fe, Hospital Universitario y Politecnico La Fe, 46026 Valencia, Spain;
| | - Jose V. Castell
- Unidad de Hepatología Experimental y Trasplante Hepático, Instituto de Investigación Sanitaria La Fe, Hospital Universitario y Politecnico La Fe, 46026 Valencia, Spain; (G.G.-L.); (S.L.-N.); (J.V.C.)
- Biochemistry and Molecular Biology Department, Universidad de Valencia, 46026 Valencia, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Roque Bort
- Unidad de Hepatología Experimental y Trasplante Hepático, Instituto de Investigación Sanitaria La Fe, Hospital Universitario y Politecnico La Fe, 46026 Valencia, Spain; (G.G.-L.); (S.L.-N.); (J.V.C.)
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, 28029 Madrid, Spain
- Correspondence: ; Tel.: +34-961-246-621
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İnci A, Kılıç Yıldırım G, Cengiz Ergin FB, Sarı S, Eğritaş Gürkan Ö, Okur İ, Biberoğlu G, Bükülmez A, Ezgü FS, Dalgıç B, Tümer L. Expected or unexpected clinical findings in liver glycogen storage disease type IX: distinct clinical and molecular variability. J Pediatr Endocrinol Metab 2022; 35:451-462. [PMID: 35038814 DOI: 10.1515/jpem-2021-0278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Accepted: 12/22/2021] [Indexed: 11/15/2022]
Abstract
OBJECTIVES To reveal the different clinical presentations of liver glycogen storage disease type IX (GSD IX), which is a clinically and genetically heterogeneous type of glycogenosis. METHODS The data from the electronic hospital records of 25 patients diagnosed with liver GSD IX was reviewed. Symptoms, clinical findings, and laboratory and molecular analysis were assessed. RESULTS Of the patients, 10 had complaints of short stature in the initial presentation additionally other clinical findings. Elevated serum transaminases were found in 20 patients, and hepatomegaly was found in 22 patients. Interestingly, three patients were referred due to neurodevelopmental delay and hypotonia, while one was referred for only autism. One patient who presented with neurodevelopmental delay developed hepatomegaly and elevated transaminases during the disease later on. Three of the patients had low hemoglobin A1C and fructosamine values that were near the lowest reference range. Two patients had left ventricular hypertrophy. Three patients developed osteopenia during follow-up, and one patient had osteoporosis after puberty. The most common gene variant, PHKA2, was observed in 16 patients, 10 variants were novel and six variants were defined before. Six patients had variants in PHKG2, two variants were not defined before and four variants were defined before. PHKB variants were found in three patients. One patient had two novel splice site mutations in trans position. It was revealed that one novel homozygous variant and one defined homozygous variant were found in PHKB. CONCLUSIONS This study revealed that GSD IX may present with only hypotonia and neurodevelopmental delay without liver involvement in the early infantile period. It should be emphasized that although liver GSDIX is thought of as a benign disease, it might present with multisystemic involvement and patients should be screened with echocardiography, bone mineral densitometry, and psychometric evaluation.
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Affiliation(s)
- Aslı İnci
- Department of Pediatric Metabolism and Nutrition, Gazi University School of Medicine, Ankara, Turkey
| | - Gonca Kılıç Yıldırım
- Department of Pediatric Metabolism and Nutrition, Osmangazi University School of Medicine, Eskisehir, Turkey
| | - Filiz Başak Cengiz Ergin
- Department of Pediatric Metabolism and Nutrition, Gazi University School of Medicine, Ankara, Turkey
| | - Sinan Sarı
- Department of Pediatric Gastroenterology and Hepatology, Gazi University School of Medicine, Ankara, Turkey
| | - Ödül Eğritaş Gürkan
- Department of Pediatric Gastroenterology and Hepatology, Gazi University School of Medicine, Ankara, Turkey
| | - İlyas Okur
- Department of Pediatric Metabolism and Nutrition, Gazi University School of Medicine, Ankara, Turkey
| | - Gürsel Biberoğlu
- Department of Pediatric Metabolism and Nutrition, Gazi University School of Medicine, Ankara, Turkey
| | - Ayşegül Bükülmez
- Department of Pediatric Gastroenterology and Hepatology, Afyon Kocatepe University School of Medicine, Afyon, Turkey
| | - Fatih Süheyl Ezgü
- Department of Pediatric Metabolism and Nutrition, Gazi University School of Medicine, Ankara, Turkey
| | - Buket Dalgıç
- Department of Pediatric Gastroenterology and Hepatology, Gazi University School of Medicine, Ankara, Turkey
| | - Leyla Tümer
- Department of Pediatric Metabolism and Nutrition, Gazi University School of Medicine, Ankara, Turkey
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Shin Y, Mun SJ, Lee J, Chung KS, Kim M, Kun Cheon C, Son MJ. Generation of human induced pluripotent stem cell line, KRIBBi003-A, from urinary cells of a patient with glycogen storage disease type IXa. Stem Cell Res 2021; 57:102584. [PMID: 34740118 DOI: 10.1016/j.scr.2021.102584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 10/18/2021] [Accepted: 10/20/2021] [Indexed: 11/17/2022] Open
Abstract
Glycogen storage disease type IXa (GSD IXa) is a rare genetic disorder characterized by phosphorylase kinase (PhK) deficiency, which leads to excessive glycogen accumulation in the liver. Urinary cells (UCs) were isolated from a GSD IXa patient and reprogrammed into induced pluripotent stem cells (iPSCs) using Sendai virus. The established iPSC line, KRIBBi003-A, exhibited pluripotency marker expression and a normal karyotype. The differentiation capacity of the cell line was confirmed by the differentiation of the three germ layers in vitro. The established iPSC line is a potential useful resource for disease modeling of GSD IXa.
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Affiliation(s)
- Yongbo Shin
- Stem Cell Convergence Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea; Department of Functional Genomics, Korea University of Science & Technology (UST), 217 Gajungro, Yuseong-gu, Daejeon 34113, Republic of Korea
| | - Seon Ju Mun
- Stem Cell Convergence Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea; Department of Functional Genomics, Korea University of Science & Technology (UST), 217 Gajungro, Yuseong-gu, Daejeon 34113, Republic of Korea
| | - Jaeseo Lee
- Stem Cell Convergence Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Kyung-Sook Chung
- Stem Cell Convergence Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea; Department of Functional Genomics, Korea University of Science & Technology (UST), 217 Gajungro, Yuseong-gu, Daejeon 34113, Republic of Korea; Biomedical Translational Research Center, KRIBB, 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Misuk Kim
- Division of Medical Genetics and Metabolism, Department of Pediatrics, Pusan National University School of Medicine, Pusan National University Children's Hospital, 20, Geumo-ro, Mulgeum-eup, Yangsan-si, Gyeongsangnam-do, Republic of Korea; Research Institute for Convergence of Biomedical Science and Technology Pusan National University Yangsan Hospital, Republic of Korea
| | - Chong Kun Cheon
- Division of Medical Genetics and Metabolism, Department of Pediatrics, Pusan National University School of Medicine, Pusan National University Children's Hospital, 20, Geumo-ro, Mulgeum-eup, Yangsan-si, Gyeongsangnam-do, Republic of Korea; Research Institute for Convergence of Biomedical Science and Technology Pusan National University Yangsan Hospital, Republic of Korea.
| | - Myung Jin Son
- Stem Cell Convergence Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea; Department of Functional Genomics, Korea University of Science & Technology (UST), 217 Gajungro, Yuseong-gu, Daejeon 34113, Republic of Korea
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Male inheritance of X-linked liver glycogenosis from an undiagnosed maternal grandfather in a Chinese pedigree: a report of two cases. JOURNAL OF BIO-X RESEARCH 2021. [DOI: 10.1097/jbr.0000000000000090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Nguyen NL, Thi Bich Ngoc C, Dung Vu C, Van Tung N, Hoang Nguyen H. A novel frameshift PHKA2 mutation in a family with glycogen storage disease type IXa: A first report in Vietnam and review of literature. Clin Chim Acta 2020; 508:9-15. [PMID: 32387637 DOI: 10.1016/j.cca.2020.05.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 05/06/2020] [Accepted: 05/06/2020] [Indexed: 11/20/2022]
Abstract
BACKGROUND Glycogen storage diseases (GSDs) are clinically and genetically heterogeneous disorders. Overlapping features between liver GSDs are a major challenge in the clinical diagnosis of them. Genetic testing can provide an early and accurate diagnosis of patients suspected with GSDs. CASE PRESENTATION In this study, we report two siblings born to healthy, non-consanguineous Vietnamese parents with hepatomegaly. The proband presented with hepatomegaly, normal spleen, elevated transaminases, without hypoglycemia, normal lactate dehydrogenase and creatine kinase. Liver biopsy revealed degeneration and swollen hepatocytes, suggesting a diagnosis with GSDs. METHODS Whole exome sequencing was applied to identify genetic variants in the proband. Variant validation and familial co-segregation analysis were examined using Sanger sequencing. RESULTS A novel frameshift duplication mutation c.3308_3312dupATGTC (p.L1105Mfs*11) of the PHKA2 gene was identified in the proband and his elder brother at the hemizygous state. This mutation was inherited from their mother. Their father and younger brother were normal genotype. CONCLUSIONS The two siblings were accurately diagnosed with GSD type XIa. This is the first case report of GSD type IXa in Vietnamese patients with a mutation in the PHKA2 gene. This finding may support for genetics diagnosis of unknown cause of hepatomegaly.
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Affiliation(s)
- Ngoc-Lan Nguyen
- Graduate University of Science and Technology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet str., Cau Giay, Hanoi 100000, Viet Nam; Institute of Genome Research, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet str., Cau Giay, Hanoi 100000, Viet Nam
| | - Can Thi Bich Ngoc
- Center for Rare Diseases and Newborn Screening, Department of Endocrinology, Metabolism and Genetics, Vietnam National Hospital of Pediatrics, 18/879 La Thanh str., Dong Da, Hanoi 100000, Viet Nam
| | - Chi Dung Vu
- Center for Rare Diseases and Newborn Screening, Department of Endocrinology, Metabolism and Genetics, Vietnam National Hospital of Pediatrics, 18/879 La Thanh str., Dong Da, Hanoi 100000, Viet Nam
| | - Nguyen Van Tung
- Graduate University of Science and Technology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet str., Cau Giay, Hanoi 100000, Viet Nam
| | - Huy Hoang Nguyen
- Graduate University of Science and Technology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet str., Cau Giay, Hanoi 100000, Viet Nam; Institute of Genome Research, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet str., Cau Giay, Hanoi 100000, Viet Nam.
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Kim TH, Kim KY, Kim MJ, Seong MW, Park SS, Moon JS, Ko JS. Molecular diagnosis of glycogen storage disease type IX using a glycogen storage disease gene panel. Eur J Med Genet 2020; 63:103921. [PMID: 32244026 DOI: 10.1016/j.ejmg.2020.103921] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 03/20/2020] [Accepted: 03/28/2020] [Indexed: 11/30/2022]
Abstract
Glycogen storage disease type IX (GSD IX) is caused by a deficiency of hepatic phosphorylase kinase. The aim of this study was to clarify the clinical features, long term outcomes, and genetic analysis of GSD IX in Korea. A GSD gene panel was created and hybridization capture-based next-generation sequencing was performed. We investigated clinical laboratory data, results of molecular genetic analysis, liver biopsy findings, and long-term outcomes. Ten children were diagnosed with GSD IX at Seoul National University Children's Hospital. Hypoglycemia, hyperlactacidemia, hypertriglyceridemia, hyperuricemia, liver fibrosis on liver biopsy, and short stature was found in 30%, 56%, 100%, 60%, 80% and 50% of the children, respectively. Seven PHKA2 variants were identified in eight children with GSD IXa-one nonsense (c.2268dupT; p.(Asp757Ter)), two splicing (c.918+1G > A, c.718-2A > G), one frameshift (c.405_419delinsTCCTGGCC; p.(Asp136ProfsTer11)), and three missense variants (c.3628G > A; p.(Gly1210Arg), c.1245G > T and c.2746C > T; p.(Arg916Trp)). Two variants of PHKG2 were identified in two children with GSD IXc-one frameshift (c.783delC; p.(Ser262AlafsTer6)) and one missense (c.661G > A; p.(Val221Met)). Elevated liver enzymes and hypertriglyceridemia in children with GSD IXa tended to improve with age. For the first time, we report hepatocellular carcinoma in a patient with GSD IXc. The GSD gene panel is a useful diagnostic tool to confirm GSD IX. The clinical phenotype of GSD IXc is severe and monitoring for the development of hepatocellular carcinoma should be implemented.
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Affiliation(s)
- Tae Hyeong Kim
- Department of Pediatrics, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Kwang Yeon Kim
- Department of Pediatrics, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Man Jin Kim
- Department of Laboratory Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Moon-Woo Seong
- Department of Laboratory Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Sung Sup Park
- Department of Laboratory Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Jin Soo Moon
- Department of Pediatrics, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Jae Sung Ko
- Department of Pediatrics, Seoul National University College of Medicine, Seoul, Republic of Korea.
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Yang F, Xu Y, Fang C, Tan L, Tan Q, Zhou Y. Clinical and genetic characteristics of three Chinese patients with glycogen storage disease type Ⅸα. Pediatr Neonatol 2019; 60:463-466. [PMID: 31248825 DOI: 10.1016/j.pedneo.2019.05.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Revised: 03/24/2019] [Accepted: 05/16/2019] [Indexed: 12/14/2022] Open
Affiliation(s)
- Fengxia Yang
- Department of Infectious Disease, Guangzhou Women and Children's Medical Center, Guangzhou, China.
| | - Yi Xu
- Department of Infectious Disease, Guangzhou Women and Children's Medical Center, Guangzhou, China.
| | - Chunxiao Fang
- Department of Infectious Disease, Guangzhou Women and Children's Medical Center, Guangzhou, China.
| | - Limei Tan
- Department of Infectious Disease, Guangzhou Women and Children's Medical Center, Guangzhou, China.
| | - Qianqian Tan
- Wuhan Kindstar Diagnostics Co., Ltd, Wuhan, China.
| | - Yong Zhou
- Wuhan Kindstar Diagnostics Co., Ltd, Wuhan, China.
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Stefater MA, Wolfsdorf JI, Ma NS, Majzoub JA. Glycogen storage disease presenting as Cushing syndrome. JIMD Rep 2019; 47:17-22. [PMID: 31240162 PMCID: PMC6498823 DOI: 10.1002/jmd2.12031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 03/11/2019] [Indexed: 01/30/2023] Open
Abstract
Impaired growth is common in patients with glycogen storage disease (GSD), who also may have "cherubic" facies similar to the "moon" facies of Cushing syndrome (CS). An infant presented with moon facies, growth failure, and obesity. Laboratory evaluation of the hypothalamic-pituitary-adrenal (HPA) axis was consistent with CS. He was subsequently found to have liver disease, hypoglycemia, and a pathogenic variant in PHKA2, leading to the diagnosis of GSD type IXa. The cushingoid appearance, poor linear growth and hypercortisolemia improved after treatment to prevent recurrent hypoglycemia. We suspect this child's HPA axis activation was "appropriate" and caused by chronic hypoglycemic stress, leading to increased glucocorticoid secretion that may have contributed to his poor growth and excessive weight gain. This is in contrast to typical CS, which is due to excessive adrenocorticotropic hormone (ACTH) or cortisol secretion from neoplastic pituitary or adrenal glands, ectopic secretion of ACTH or corticotropin-releasing hormone (CRH), or exogenous administration of corticosteroid or ACTH. Pseudo-CS is a third cause of excessive glucocorticoid secretion, has no HPA axis pathology, is most often associated with underlying psychiatric disorders or obesity in children and, by itself, is thought to be benign. We speculate that some diseases, including chronic hypoglycemic disorders such as the GSDs, may have biochemical features and pathologic consequences of CS. We propose that excessive glucocorticoid secretion due to chronic stress be termed "stress-induced Cushing (SIC) syndrome" to distinguish it from the other causes of CS and pseudo-CS, and that evaluation of children with chronic hypoglycemia and poor statural growth include evaluation for CS.
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Affiliation(s)
- Margaret A. Stefater
- Division of Endocrinology, Department of PediatricsBoston Children's Hospital, Harvard Medical SchoolBostonMassachusetts
| | - Joseph I. Wolfsdorf
- Division of Endocrinology, Department of PediatricsBoston Children's Hospital, Harvard Medical SchoolBostonMassachusetts
| | - Nina S. Ma
- Division of Endocrinology, Department of PediatricsBoston Children's Hospital, Harvard Medical SchoolBostonMassachusetts
| | - Joseph A. Majzoub
- Division of Endocrinology, Department of PediatricsBoston Children's Hospital, Harvard Medical SchoolBostonMassachusetts
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Kishnani PS, Goldstein J, Austin SL, Arn P, Bachrach B, Bali DS, Chung WK, El-Gharbawy A, Brown LM, Kahler S, Pendyal S, Ross KM, Tsilianidis L, Weinstein DA, Watson MS. Diagnosis and management of glycogen storage diseases type VI and IX: a clinical practice resource of the American College of Medical Genetics and Genomics (ACMG). Genet Med 2019; 21:772-789. [PMID: 30659246 DOI: 10.1038/s41436-018-0364-2] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 10/15/2018] [Indexed: 01/10/2023] Open
Abstract
PURPOSE Glycogen storage disease (GSD) types VI and IX are rare diseases of variable clinical severity affecting primarily the liver. GSD VI is caused by deficient activity of hepatic glycogen phosphorylase, an enzyme encoded by the PYGL gene. GSD IX is caused by deficient activity of phosphorylase kinase (PhK), the enzyme subunits of which are encoded by various genes: ɑ (PHKA1, PHKA2), β (PHKB), ɣ (PHKG1, PHKG2), and δ (CALM1, CALM2, CALM3). Glycogen storage disease types VI and IX have a wide spectrum of clinical manifestations and often cannot be distinguished from each other, or from other liver GSDs, on clinical presentation alone. Individuals with GSDs VI and IX can present with hepatomegaly with elevated serum transaminases, ketotic hypoglycemia, hyperlipidemia, and poor growth. This guideline for the management of GSDs VI and IX was developed as an educational resource for health-care providers to facilitate prompt and accurate diagnosis and appropriate management of patients. METHODS A national group of experts in various aspects of GSDs VI and IX met to review the limited evidence base from the scientific literature and provided their expert opinions. Consensus was developed in each area of diagnosis, treatment, and management. Evidence bases for these rare disorders are largely based on expert opinion, particularly when targeted therapeutics that have to clear the US Food and Drug Administration (FDA) remain unavailable. RESULTS This management guideline specifically addresses evaluation and diagnosis across multiple organ systems involved in GSDs VI and IX. Conditions to consider in a differential diagnosis stemming from presenting features and diagnostic algorithms are discussed. Aspects of diagnostic evaluation and nutritional and medical management, including care coordination, genetic counseling, and prenatal diagnosis are addressed. CONCLUSION A guideline that will facilitate the accurate diagnosis and optimal management of patients with GSDs VI and IX was developed. This guideline will help health-care providers recognize patients with GSDs VI and IX, expedite diagnosis, and minimize adverse sequelae from delayed diagnosis and inappropriate management. It will also help identify gaps in scientific knowledge that exist today and suggest future studies.
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Affiliation(s)
| | | | | | - Pamela Arn
- Nemours Children's Clinic, Jacksonville, FL, USA
| | - Bert Bachrach
- University of Missouri Health System, Columbia, MO, USA
| | | | - Wendy K Chung
- Columbia University Medical Center, New York, NY, USA
| | | | - Laurie M Brown
- University of Florida College of Medicine, Gainesville, FL, USA
| | | | | | - Katalin M Ross
- Connecticut Children's Medical Center, Hartford, CT, USA
| | | | - David A Weinstein
- University of Connecticut School of Medicine, Connecticut Children's Hospital, Hartford, CT, USA
| | - Michael S Watson
- American College of Medical Genetics and Genomics, Bethesda, MD, USA.
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Bali DS, Goldstein JL, Fredrickson K, Austin S, Pendyal S, Rehder C, Kishnani PS. Clinical and Molecular Variability in Patients with PHKA2 Variants and Liver Phosphorylase b Kinase Deficiency. JIMD Rep 2017; 37:63-72. [PMID: 28283841 DOI: 10.1007/8904_2017_8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 12/29/2016] [Accepted: 01/30/2017] [Indexed: 03/17/2023] Open
Abstract
Glycogen storage disease (GSD) type IX is a rare disease of variable clinical severity affecting primarily the liver tissue. Individuals with liver phosphorylase b kinase (PhK) deficiency (GSD IX) can present with hepatomegaly with elevated serum transaminases, ketotic hypoglycemia, hyperlipidemia, and poor growth with considerable variation in clinical severity. PhK is a cAMP-dependent protein kinase that phosphorylates the inactive form of glycogen phosphorylase, phosphorylase b, to produce the active form, phosphorylase a. PhK is a heterotetramer; the alpha 2 subunit in the liver is encoded by the X-linked PHKA2 gene. About 75% of individuals with liver PhK deficiency have mutations in the PHKA2 gene; this condition is also known as X-linked glycogenosis (XLG). Here we report the variability in clinical severity and laboratory findings in 12 male patients from 10 different families with X-linked liver PhK deficiency caused by mutations in PHKA2. We found that there is variability in the severity of clinical features, including hypoglycemia and growth. We also report additional PHKA2 variants that were identified in 24 patients suspected to have liver PhK deficiency. The basis of the clinical variation in GSDIX due to X-linked PHKA2 gene mutations is currently not well understood. Creating systematic registries, and collecting longitudinal data may help in better understanding of this rare, but common, glycogen storage disorder. SYNOPSIS Liver phosphorylase b kinase (PhK) deficiency caused due to mutations in X-linked PHKA2 is highly variable.
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Affiliation(s)
- Deeksha S Bali
- Department of Pediatrics, Duke Medicine, Durham, NC, USA. .,Biochemical Genetics Laboratory, Duke Medicine, 801-6 Capitola Drive, Durham, NC, 27713, USA.
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Spillmann F, Kühl U, Van Linthout S, Dominguez F, Escher F, Schultheiss HP, Pieske B, Tschöpe C. Reversible transition from a hypertrophic to a dilated cardiomyopathy. ESC Heart Fail 2016; 3:138-142. [PMID: 27774273 PMCID: PMC5064744 DOI: 10.1002/ehf2.12072] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 09/10/2015] [Accepted: 10/01/2015] [Indexed: 12/04/2022] Open
Abstract
We report the case of a 17‐year‐old female patient with known hypertrophic cardiomyopathy and a Wolff‐Parkinson‐White syndrome. She came to our department for further evaluation of a new diagnosed dilated cardiomyopathy characterized by an enlargement of the left ventricle and a fall in ejection fraction. Clinically, she complained about atypical chest pain, arrhythmic episodes with presyncopal events, and dyspnea (NYHA III) during the last 6 months. Non‐invasive and invasive examinations including magnetic resonance imaging, electrophysiological examinations, and angiography did not lead to a conclusive diagnosis. Therefore, endomyocardial biopsies (EMBs) were taken to investigate whether a specific myocardial disease caused the impairment of the left ventricular function. EMB analysis resulted in the diagnosis of a virus‐negative, active myocarditis. Based on this diagnosis, an immunosuppressive treatment with prednisolone and azathioprine was started, which led to an improvement of cardiac function and symptoms within 3 months after initiating therapy. In conclusion, we show that external stress triggered by myocarditis can induce a reversible transition from a hypertrophic cardiomyopathy to a dilated cardiomyopathy phenotype. This case strongly underlines the need for a thorough and invasive examination of heart failure of unknown causes, including EMB investigations as recommend by the actual ESC position statement.
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Affiliation(s)
- Frank Spillmann
- Department of Cardiology Charité-University Medicine of Berlin, Campus Virchow Klinikum Berlin Germany
| | - Uwe Kühl
- Department of Cardiology Charité-University Medicine of Berlin, Campus Virchow Klinikum Berlin Germany
| | - Sophie Van Linthout
- Berlin-Brandenburg Center for Regenerative Therapies (BCRT)Charité-University Medicine of Berlin, Campus Virchow KlinikumBerlinGermany; Deutsches Zentrum für Herz-Kreislaufforschung (DZHK)-Standort Berlin/CharitéBerlinGermany
| | - Fernando Dominguez
- Department of Cardiology Hospital Universitario Puerta de Hierro Madrid Spain
| | - Felicitas Escher
- Department of CardiologyCharité-University Medicine of Berlin, Campus Virchow KlinikumBerlinGermany; IKDT-Institut kardiale Diagnostik und Therapie GmbHBerlinGermany
| | | | - Burkert Pieske
- Department of CardiologyCharité-University Medicine of Berlin, Campus Virchow KlinikumBerlinGermany; Deutsches Zentrum für Herz-Kreislaufforschung (DZHK)-Standort Berlin/CharitéBerlinGermany; Department of CardiologyDeutsches Herzzentrum Berlin (DHZB)BerlinGermany
| | - Carsten Tschöpe
- Department of CardiologyCharité-University Medicine of Berlin, Campus Virchow KlinikumBerlinGermany; Berlin-Brandenburg Center for Regenerative Therapies (BCRT)Charité-University Medicine of Berlin, Campus Virchow KlinikumBerlinGermany; Deutsches Zentrum für Herz-Kreislaufforschung (DZHK)-Standort Berlin/CharitéBerlinGermany
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12
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Chen MA, Weinstein DA. Glycogen storage diseases: Diagnosis, treatment and outcome. ACTA ACUST UNITED AC 2016. [DOI: 10.3233/trd-160006] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
| | - David A. Weinstein
- Glycogen Storage Disease Program, University of Florida College of Medicine, Gainesville, FL, USA
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13
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Karande IS, Boulter E, Queit L, Balasubramaniam S. Structured Dietary Management Dramatically Improves Marked Transaminitis, Metabolic and Clinical Profiles in Glycogen Storage Disease Type IXa. JOURNAL OF INBORN ERRORS OF METABOLISM AND SCREENING 2016. [DOI: 10.1177/2326409816682766] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- Indrajit S. Karande
- Metabolic Unit, Department of Rheumatology and Metabolic Medicine, Princess Margaret Hospital, Perth, Western Australia, Australia
| | - Emily Boulter
- Metabolic Unit, Department of Rheumatology and Metabolic Medicine, Princess Margaret Hospital, Perth, Western Australia, Australia
| | - Leah Queit
- Department of Nutrition and Dietetics, Princess Margaret Hospital, Perth, Western Australia, Australia
| | - Shanti Balasubramaniam
- Metabolic Unit, Department of Rheumatology and Metabolic Medicine, Princess Margaret Hospital, Perth, Western Australia, Australia
- School of Paediatrics and Child Health, University of Western Australia, Perth, Western Australia, Australia
- Western Sydney Genetics Program, Children’s Hospital at Westmead, Westmead, New South Wales, Australia
- Discipline of Genetic Medicine & Paediatrics and Child Health, University of Sydney, New South Wales, Australia
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14
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Choi R, Park HD, Kang B, Choi SY, Ki CS, Lee SY, Kim JW, Song J, Choe YH. PHKA2 mutation spectrum in Korean patients with glycogen storage disease type IX: prevalence of deletion mutations. BMC MEDICAL GENETICS 2016; 17:33. [PMID: 27103379 PMCID: PMC4839068 DOI: 10.1186/s12881-016-0295-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/29/2015] [Accepted: 04/14/2016] [Indexed: 11/26/2022]
Abstract
Background Molecular diagnosis of glycogen storage diseases (GSDs) is important to enable accurate diagnoses and make appropriate therapeutic plans. The aim of this study was to evaluate the PHKA2 mutation spectrum in Korean patients with GSD type IX. Methods Thirteen Korean patients were tested for PHKA2 mutations using direct sequencing and a multiplex polymerase chain reaction method. A comprehensive review of the literature on previously reported PHKA2 mutations in other ethnic populations was conducted for comparison. Results Among 13 patients tested, six unrelated male patients with GSD IX aged 2 to 6 years at the first diagnostic work-up for hepatomegaly with elevated aspartate transaminase (AST) and alanine transaminase (ALT) were found to have PHKA2 mutations. These patients had different PHKA2 mutations: five were known mutations (c.537 + 5G > A, c.884G > A [p.Arg295His], c.3210_3212delGAG [p.Arg1072del], exon 8 deletion, and exons 27–33 deletion) and one was a novel mutation (exons 18–33 deletion). Notably, the most common type of mutation was gross deletion, in contrast to other ethnic populations in which the most common mutation type was sequence variant. Conclusions This study expands our knowledge of the PHKA2 mutation spectrum of GSD IX. Considering the PHKA2 mutation spectrum in Korean patients with GSD IX, molecular diagnostic methods for deletions should be conducted in conjunction with direct sequence analysis to enable accurate molecular diagnosis of this disease in the Korean population.
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Affiliation(s)
- Rihwa Choi
- Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul, 135-710, Republic of Korea
| | - Hyung-Doo Park
- Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul, 135-710, Republic of Korea.
| | - Ben Kang
- Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - So Yoon Choi
- Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Chang-Seok Ki
- Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul, 135-710, Republic of Korea
| | - Soo-Youn Lee
- Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul, 135-710, Republic of Korea
| | - Jong-Won Kim
- Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul, 135-710, Republic of Korea
| | - Junghan Song
- Department of Laboratory Medicine, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Republic of Korea
| | - Yon Ho Choe
- Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
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15
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Albash B, Imtiaz F, Al-Zaidan H, Al-Manea H, Banemai M, Allam R, Al-Suheel A, Al-Owain M. Novel PHKG2 mutation causing GSD IX with prominent liver disease: report of three cases and review of literature. Eur J Pediatr 2014; 173:647-53. [PMID: 24326380 DOI: 10.1007/s00431-013-2223-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Accepted: 11/20/2013] [Indexed: 10/25/2022]
Abstract
Glycogen storage disease type IX (GSD IX) is a common form of glycogenosis due to mutations in PHKA1, PHKA2, or PHKB and PHKG2 genes resulting in the deficiency of phosphorylase kinase. The first two genes are X-linked while the latter two follow an autosomal recessive inheritance. The majority of cases of GSD IX are attributed to defects in PHKA2 which usually cause a mild disease. We report three patients with PHKG2-related GSD IX presenting with significant hepatic involvement, fibrosis, and cirrhosis. Interestingly, the homozygosity mapping resolved a dilemma about an erroneously normal phosphorylase kinase activity in patient 1. The novel mutation found in all the three patients (p.G220E) affects the catalytic subunit of the phosphorylase kinase. Increasing evidence shows that patients with PHKG2 mutations have a severe hepatic phenotype within the heterogeneous GSD IX disorder. Therefore, defect in PHKG2 should be considered in patients with suspected glycogenosis associated with significant liver fibrosis and cirrhosis.
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16
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17
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Achouitar S, Goldstein JL, Mohamed M, Austin S, Boyette K, Blanpain FM, Rehder CW, Kishnani PS, Wortmann SB, den Heijer M, Lefeber DJ, Wevers RA, Bali DS, Morava E. Common mutation in the PHKA2 gene with variable phenotype in patients with liver phosphorylase b kinase deficiency. Mol Genet Metab 2011; 104:691-4. [PMID: 21911307 DOI: 10.1016/j.ymgme.2011.08.021] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2011] [Revised: 08/19/2011] [Accepted: 08/19/2011] [Indexed: 11/23/2022]
Abstract
We found that the missense mutation p.Pro1205Leu in the PHKA2 gene is a common cause of hepatic phosphorylase-kinase deficiency in Dutch patients, suggesting a founder-effect. Most patients presented with isolated growth delay and diarrhea, prior to the occurrence of hepatomegaly, delaying diagnosis. Tetraglucoside excretion correlated with disease severity and was used to follow compliance. The clinical presentation and therapeutic requirements in the same mutation carriers were variable, and PhK deficiency necessitated tube-feeding in some children.
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Affiliation(s)
- Samira Achouitar
- Department of Pediatrics, Institute for Genetic and Metabolic Disease, Radboud University Nijmegen Medical Center, The Netherlands
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18
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DiMauro S, Spiegel R. Progress and problems in muscle glycogenoses. ACTA MYOLOGICA : MYOPATHIES AND CARDIOMYOPATHIES : OFFICIAL JOURNAL OF THE MEDITERRANEAN SOCIETY OF MYOLOGY 2011; 30:96-102. [PMID: 22106711 PMCID: PMC3235878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
In this selective review, we consider a number of unsolved questions regarding the glycogen storage diseases (GSD). Thus, the pathogenesis of Pompe disease (GSD II) is not simply explained by excessive intralysosomal glycogen storage and may relate to a more general dysfunction of autophagy. It is not clear why debrancher deficiency (GSD III) causes fixed myopathy rather than exercise intolerance, unless this is due to the frequent accompanying neuropathy. The infantile neuromuscular presentation of branching enzyme deficiency (GSD IV) is underdiagnosed and is finally getting the attention it deserves. On the other hand, the late-onset variant of GSD IV (adult polyglucosan body disease APBD) is one of several polyglucosan disorders (including Lafora disease) due to different etiologies. We still do not understand the clinical heterogeneity of McArdle disease (GSD V) or the molecular basis of the rare fatal infantile form. Similarly, the multisystemic infantile presentation of phosphofructokinase deficiency (GSD VII) is a conundrum. We observed an interesting association between phosphoglycerate kinase deficiency (GSD IX) and juvenile Parkinsonism, which is probably causal rather than casual. Also unexplained is the frequent and apparently specific association of phosphoglycerate mutase deficiency (GSD X) and tubular aggregates. By paying more attention to problems than to progress, we aimed to look to the future rather than to the past.
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Affiliation(s)
- S. DiMauro
- Address for correspondence: Salvatore DiMauro, MD, 4-424B College of Physicians & Surgeons, 630 West 168th Street, New York, NY
10032, USA. Tel. +212 305 1662. Fax +212 305 3986. E-mail:
| | - R. Spiegel
- Department of Pediatrics, HaEmek Medical
Center, Rappaport School of Medicine, Afula, Israel
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19
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Davit-Spraul A, Piraud M, Dobbelaere D, Valayannopoulos V, Labrune P, Habes D, Bernard O, Jacquemin E, Baussan C. Liver glycogen storage diseases due to phosphorylase system deficiencies: diagnosis thanks to non invasive blood enzymatic and molecular studies. Mol Genet Metab 2011; 104:137-43. [PMID: 21646031 DOI: 10.1016/j.ymgme.2011.05.010] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2011] [Revised: 05/11/2011] [Accepted: 05/11/2011] [Indexed: 10/18/2022]
Abstract
Glycogen storage disease (GSD) due to a deficient hepatic phosphorylase system defines a genetically heterogeneous group of disorders that mainly manifests in children. We investigated 45 unrelated children in whom a liver GSD VI or IX was suspected on the basis of clinical symptoms including hepatomegaly, increased serum transaminases, postprandial lactatemia and/or mild fasting hypoglycemia. Liver phosphorylase and phosphorylase b kinase activities studied in peripheral blood cells allowed to suspect diagnosis in 37 cases but was uninformative in 5. Sequencing of liver phosphorylase genes was useful to establish an accurate diagnosis. Causative mutations were found either in the PYGL (11 patients), PHKA2 (26 patients), PHKG2 (three patients) or in the PHKB (three patients) genes. Eleven novel disease causative mutations, five missense (p.N188K, p.D228Y, p.P382L, p.R491H, p.L500R) and six truncating mutations (c.501_502ins361pb, c.528+2T>C, c.856-29_c.1518+614del, c.1620+1G>C, p.E703del and c.2313-1G>T) were identified in the PYGL gene. Seventeen novel disease causative mutations, ten missense (p.A42P, p.Q95R, p.G131D, p.G131V, p.Q134R, p.G187R, p.G300V, p.G300A, p.C326Y, p.W820G) and seven truncating (c.537+5G>A, p.G396DfsX28, p.Q404X, p.N653X, p.L855PfsX87, and two large deletions) were identified in the PHKA2 gene. Four novel truncating mutations (p.R168X, p.Q287X, p.I268PfsX12 and c.272-1G>C) were identified in the PHKG2 gene and three (c.573_577del, p.R364X, c.2427+3A>G) in the PHKB gene. Patients with PHKG2 mutations evolved towards cirrhosis. Molecular analysis of GSD VI or IX genes allows to confirm diagnosis suspected on the basis of enzymatic analysis and to establish diagnosis and avoid liver biopsy when enzymatic studies are not informative in blood cells.
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Affiliation(s)
- Anne Davit-Spraul
- Biochemistry Unit, CHU Bicêtre, Assistance Publique-Hôpitaux de Paris, France.
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20
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Cole JB, Wiggans GR, Ma L, Sonstegard TS, Lawlor TJ, Crooker BA, Van Tassell CP, Yang J, Wang S, Matukumalli LK, Da Y. Genome-wide association analysis of thirty one production, health, reproduction and body conformation traits in contemporary U.S. Holstein cows. BMC Genomics 2011; 12:408. [PMID: 21831322 PMCID: PMC3176260 DOI: 10.1186/1471-2164-12-408] [Citation(s) in RCA: 292] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2010] [Accepted: 08/11/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Genome-wide association analysis is a powerful tool for annotating phenotypic effects on the genome and knowledge of genes and chromosomal regions associated with dairy phenotypes is useful for genome and gene-based selection. Here, we report results of a genome-wide analysis of predicted transmitting ability (PTA) of 31 production, health, reproduction and body conformation traits in contemporary Holstein cows. RESULTS Genome-wide association analysis identified a number of candidate genes and chromosome regions associated with 31 dairy traits in contemporary U.S. Holstein cows. Highly significant genes and chromosome regions include: BTA13's GNAS region for milk, fat and protein yields; BTA7's INSR region and BTAX's LOC520057 and GRIA3 for daughter pregnancy rate, somatic cell score and productive life; BTA2's LRP1B for somatic cell score; BTA14's DGAT1-NIBP region for fat percentage; BTA1's FKBP2 for protein yields and percentage, BTA26's MGMT and BTA6's PDGFRA for protein percentage; BTA18's 53.9-58.7 Mb region for service-sire and daughter calving ease and service-sire stillbirth; BTA18's PGLYRP1-IGFL1 region for a large number of traits; BTA18's LOC787057 for service-sire stillbirth and daughter calving ease; BTA15's CD82, BTA23's DST and the MOCS1-LRFN2 region for daughter stillbirth; and BTAX's LOC520057 and GRIA3 for daughter pregnancy rate. For body conformation traits, BTA11, BTAX, BTA10, BTA5, and BTA26 had the largest concentrations of SNP effects, and PHKA2 of BTAX and REN of BTA16 had the most significant effects for body size traits. For body shape traits, BTAX, BTA19 and BTA3 were most significant. Udder traits were affected by BTA16, BTA22, BTAX, BTA2, BTA10, BTA11, BTA20, BTA22 and BTA25, teat traits were affected by BTA6, BTA7, BTA9, BTA16, BTA11, BTA26 and BTA17, and feet/legs traits were affected by BTA11, BTA13, BTA18, BTA20, and BTA26. CONCLUSIONS Genome-wide association analysis identified a number of genes and chromosome regions associated with 31 production, health, reproduction and body conformation traits in contemporary Holstein cows. The results provide useful information for annotating phenotypic effects on the dairy genome and for building consensus of dairy QTL effects.
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Affiliation(s)
- John B Cole
- Animal Improvement Programs Laboratory, Agricultural Research Service,USDA, Beltsville, Maryland, USA
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21
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Lau CK, Hui J, Fong FNY, To KF, Fok TF, Tang NLS, Tsui SKW. Novel mutations in PHKA2 gene in glycogen storage disease type IX patients from Hong Kong, China. Mol Genet Metab 2011; 102:222-5. [PMID: 21131218 DOI: 10.1016/j.ymgme.2010.11.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2010] [Accepted: 11/04/2010] [Indexed: 11/22/2022]
Abstract
The diagnosis of glycogen storage disease (GSD) type IX is often complicated by the complexity of the phosphorylase kinase enzyme (PHK), and molecular analysis is the preferred way to provide definitive diagnosis. Here we reported two novel mutations found in two GSD type IX patients with different residual enzyme activities from Hong Kong, China using genetic analysis and, provided the molecular interpretation of the deficient PHK activity. These two newly described mutations would be useful for the study of future GSD patients.
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Affiliation(s)
- Chi-Kong Lau
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
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22
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Boulatnikov IG, Peters JL, Nadeau OW, Sage JM, Daniels PJ, Kumar P, Walsh DA, Carlson GM. Expressed phosphorylase b kinase and its alphagammadelta subcomplex as regulatory models for the rabbit skeletal muscle holoenzyme. Biochemistry 2009; 48:10183-91. [PMID: 19764815 DOI: 10.1021/bi901429y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Understanding the regulatory interactions among the 16 subunits of the (alphabetagammadelta)(4) phosphorylase b kinase (PhK) complex can only be achieved through reconstructing the holoenzyme or its subcomplexes from the individual subunits. In this study, recombinant baculovirus carrying a vector containing a multigene cassette was created to coexpress in insect cells alpha, beta, gamma, and delta subunits corresponding to rabbit skeletal muscle PhK. The hexadecameric recombinant PhK (rPhK) and its corresponding alphagammadelta trimeric subcomplex were purified to homogeneity with proper subunit stoichiometries. The catalytic activity of rPhK at pH 8.2 and its ratio of activities at pH 6.8 versus pH 8.2 were comparable to those of PhK purified from rabbit muscle (RM PhK), as was the hysteresis (autoactivation) in the rate of product formation at pH 6.8. Both the rPhK and alphagammadelta exhibited only a very low Ca(2+)-independent activity and a Ca(2+)-dependent activity similar to that of the native holoenzyme with [Ca(2+)](0.5) of 0.4 microM for the RM PhK, 0.7 microM for the rPhK, and 1.5 microM for the alphagammadelta trimer. The RM PhK, rPhK, and alphagammadelta subcomplex were also all activated through self-phosphorylation. Using cross-linking and limited proteolysis, the alpha-gamma intersubunit contacts previously observed within the intact RM PhK complex were also observed within the recombinant alphagammadelta subcomplex. Our results indicate that both the rPhK and alphagammadelta subcomplex are promising models for future structure-function studies on the regulation of PhK activity through intersubunit contacts, because both retained the regulatory properties of the enzyme purified from skeletal muscle.
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Affiliation(s)
- Igor G Boulatnikov
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, Kansas 66160, USA
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23
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Chen ST, Chen HL, Ni YH, Chien YH, Jeng YM, Chang MH, Hwu WL. X-linked liver glycogenosis in a Taiwanese family: transmission from undiagnosed males. Pediatr Neonatol 2009; 50:230-3. [PMID: 19856867 DOI: 10.1016/s1875-9572(09)60068-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
X-linked liver glycogenosis (XLG), also known as glycogen storage disease type-lXa, is characterized by hepatomegaly, abnormal liver functions and growth retardation. It is caused by mutations in the PHKA2 gene that encodes the alpha-subunit of phosphorylase kinase (PHK). XLG can be divided into two subtypes: XLG-I, with a deficiency in PHK activity in peripheral blood cells and the liver; and XLG-II, with normal PHK activity in vitro. This report describes two boys who presented with hepatomegaly and abnormal liver function. Pedigree analysis revealed them to be fifth-degree relatives, with the disease transmitted through undiagnosed grandfathers. Liver histology confirmed GSD diagnosis, and both cases had a deficiency in PHK activity in red blood cells and liver tissues. This is the first report of XLG-I in the ethnic-Chinese population in Taiwan. This report indicates that XLG may be undiagnosed or underestimated. A correct diagnosis is necessary for proper management and genetic counseling.
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Affiliation(s)
- Szu-Ta Chen
- Department of Pediatrics, National Taiwan University Children's Hospital and National Taiwan University College of Medicine, Taipei, Taiwan
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24
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3D mapping of glycogenosis-causing mutations in the large regulatory alpha subunit of phosphorylase kinase. Biochim Biophys Acta Mol Basis Dis 2008; 1782:664-70. [DOI: 10.1016/j.bbadis.2008.09.011] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2008] [Revised: 09/15/2008] [Accepted: 09/19/2008] [Indexed: 11/20/2022]
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25
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Akman HO, Sampayo JN, Ross FA, Scott JW, Wilson G, Benson L, Bruno C, Shanske S, Hardie DG, Dimauro S. Fatal infantile cardiac glycogenosis with phosphorylase kinase deficiency and a mutation in the gamma2-subunit of AMP-activated protein kinase. Pediatr Res 2007; 62:499-504. [PMID: 17667862 DOI: 10.1203/pdr.0b013e3181462b86] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A 10-wk-old infant girl with severe hypertrophy of the septal and atrial walls by cardiac ultrasound, developed progressive ventricular wall thickening and died of aspiration pneumonia at 5 mo of age. Postmortem examination revealed ventricular hypertrophy and massive atrial wall thickening due to glycogen accumulation. A skeletal muscle biopsy showed increased free glycogen and decreased activity of phosphorylase b kinase (PHK). The report of a pathogenic mutation (R531Q) in the gene (PRKAG2) encoding the gamma2 subunit of AMP-activated protein kinase (AMPK) in three infants with congenital hypertrophic cardiomyopathy, glycogen storage, and "pseudo PHK deficiency" prompted us to screen this gene in our patient. We found a novel (R384T) heterozygous mutation in PRKAG2, affecting an arginine residue in the N-terminal AMP-binding domain. Like R531Q, this mutation reduces the binding of AMP and ATP to the isolated nucleotide-binding domains, and prevents activation of the heterotrimer by metabolic stress in intact cells. The mutation was not found in DNA from the patient's father, the only available parent, and is likely to have arisen de novo. Our studies confirm that mutations in PRKAG2 can cause fatal infantile cardiomyopathy, often associated with apparent PHK deficiency.
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Affiliation(s)
- Hasan O Akman
- Department of Neurology, Columbia University Medical Center, New York, NY 10032, USA, and Department of Cardiology, Hospital for Sick Children, Toronto, Ontario, Canada M5G 1X8
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26
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Fukao T, Zhang G, Aoki Y, Arai T, Teramoto T, Kaneko H, Sugie H, Kondo N. Identification of Alu-mediated, large deletion-spanning introns 19-26 in PHKA2 in a patient with X-linked liver glycogenosis (hepatic phosphorylase kinase deficiency). Mol Genet Metab 2007; 92:179-82. [PMID: 17581768 DOI: 10.1016/j.ymgme.2007.05.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2007] [Revised: 05/09/2007] [Accepted: 05/09/2007] [Indexed: 11/20/2022]
Abstract
X-linked liver glycogenosis (XLG) is one of the most common glycogen storage diseases. We present the first case of a large PHKA2 gene deletion from intron 19 to intron 26 in an XLG patient. An aberrant cDNA with skipping of exons 20-26 was detected. Alu element-mediated unequal homologous recombination between an Alu-Jo in intron 19 and another Alu-Sg in intron 26 appears to be responsible for this deletion.
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Affiliation(s)
- Toshiyuki Fukao
- Department of Pediatrics, Graduate School of Medicine, Gifu University, Gifu 501-1194, Japan
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27
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Beauchamp NJ, Dalton A, Ramaswami U, Niinikoski H, Mention K, Kenny P, Kolho KL, Raiman J, Walter J, Treacy E, Tanner S, Sharrard M. Glycogen storage disease type IX: High variability in clinical phenotype. Mol Genet Metab 2007; 92:88-99. [PMID: 17689125 DOI: 10.1016/j.ymgme.2007.06.007] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2007] [Revised: 06/14/2007] [Accepted: 06/15/2007] [Indexed: 10/23/2022]
Abstract
Glycogen storage disease type IX (GSD type IX) results from a deficiency of hepatic phosphorylase kinase activity. The phosphorylase kinase holoenzyme is made up of four copies of each of four subunits (alpha, beta, gamma and delta). The liver isoforms of the alpha-, beta- and gamma-subunits are encoded by PHKA2, PHKB and PHKG2, respectively. Mutation within these genes has been shown to result in GSD type IX. The diagnosis of GSD type IX is complicated by the spectrum of clinical symptoms, variation in tissue specificity and severity, and its inheritance, either X-linked or autosomal recessive. We investigated 15 patients from 12 families with suspected GSD type IX. Accurate diagnosis had been hampered by enzymology not being diagnostic in five cases. Clinical symptoms included combinations of hypoglycaemia, hepatosplenomegaly, short stature, hepatopathy, weakness, fatigue and motor delay. Biochemical findings included elevated lactate, urate and lipids. We characterised causative mutations in the PHKA2 gene in ten patients from eight families, in PHKG2 in two unrelated patients and in the PHKB gene in three patients from two families. Seven novel mutations were identified in PHKA2 (p.I337X, p.P498L, p.P869R, p.Y116_T120dup, p.R1070del, p.R916W and p.M113I), two in PHKG2 (p.L144P and p.H48QfsX5) and two in PHKB (p.Y419X and c.2336+965A>C). There was a severe phenotype in patients with PHKG2 mutations, a mild phenotype with patients PHKB mutations and a broad spectrum associated with PHKA2 mutations. Molecular analysis allows accurate diagnosis where enzymology is uninformative and identifies the pattern of inheritance permitting counselling and family studies.
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Affiliation(s)
- Nicholas James Beauchamp
- Academic Unit of Child Health, University of Sheffield, Stephenson Wing, Sheffield Children's NHS Foundation Trust, Western Bank, Sheffield S10 2TH, and Department of Paediatrics, Addenbrook's Hospital, Cambridge, UK.
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Hidaka F, Sawada H, Matsuyama M, Nunoi H. A novel mutation of the PHKA2 gene in a patient with X-linked liver glycogenosis type 1. Pediatr Int 2005; 47:687-90. [PMID: 16354226 DOI: 10.1111/j.1442-200x.2005.02131.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Fumio Hidaka
- Department of Pediatrics, Miyazaki Medical College, University of Miyazaki, Miyazaki, Japan
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Burwinkel B, Rootwelt T, Kvittingen EA, Chakraborty PK, Kilimann MW. Severe phenotype of phosphorylase kinase-deficient liver glycogenosis with mutations in the PHKG2 gene. Pediatr Res 2003; 54:834-9. [PMID: 12930917 DOI: 10.1203/01.pdr.0000088069.09275.10] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Phosphorylase kinase-deficient liver glycogenosis manifests in infancy with hepatomegaly, growth retardation, and elevated plasma aminotransferases and lipids. It can be caused by mutations in three different genes of phosphorylase kinase subunits: PHKA2, PHKB, and PHKG2. It is usually a benign condition, often with complete resolution of symptoms during puberty. A minority of patients displays a more severe phenotype with symptomatic fasting hypoglycemia and abnormal liver histology that may progress to cirrhosis. Three patients with liver cirrhosis in childhood analyzed previously all had PHKG2 mutations. This suggested that this genotype may generally cause a more severe clinical manifestation, but to date PHKG2 mutations have been identified in only seven patients. Here, we report mutation analysis in three new patients with liver phosphorylase kinase deficiency and recurrent hypoglycemia, liver fibrosis, and lack of glucagon response but no overt cirrhosis. In all three patients, PHKG2 mutations were found (H89fs[insC], E157K, D215N, W300X). Three of these mutations are novel, bringing the total number of distinct human PHKG2 mutations to 11, found in 10 patients. We conclude that liver phosphorylase kinase deficiency with a severe phenotype, with or without cirrhosis, is indeed often caused by PHKG2 mutations. These patients require active measures to maintain normoglycemia (raw cornstarch, nocturnal tube feeding), which may also alleviate growth retardation and the development of abnormal liver histology.
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Affiliation(s)
- Barbara Burwinkel
- Institut für Physiologische Chemie, Ruhr-Universität Bochum, D-44780 Bochum, Germany
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30
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Abstract
Phosphorylase kinase is a four-subunit enzyme involved in the regulation of glycogen breakdown. The traditional textbook view is that only the gamma subunit has enzymatic activity, whereas the other three subunits have a regulatory role. Evidence from homology searches and sequence alignments, however, shows that the alpha- and beta-subunits possess amino-terminal glucoamylase-like domains and suggests that they might possess a previously overlooked amylase activity. If true, this would have important implications for the understanding, diagnosis, and management of glycogen storage diseases. There is thus a clear need to test this hypothesis through enzymatic assays and structural studies.
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Affiliation(s)
- Mark J Pallen
- Division of Immunity and Infection, University of Birmingham Medical School, Vincent Drive, Edgbaston, Birmingham B15 2TT, UK.
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Burwinkel B, Hu B, Schroers A, Clemens PR, Moses SW, Shin YS, Pongratz D, Vorgerd M, Kilimann MW. Muscle glycogenosis with low phosphorylase kinase activity: mutations in PHKA1, PHKG1 or six other candidate genes explain only a minority of cases. Eur J Hum Genet 2003; 11:516-26. [PMID: 12825073 DOI: 10.1038/sj.ejhg.5200996] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Muscle-specific deficiency of phosphorylase kinase (Phk) causes glycogen storage disease, clinically manifesting in exercise intolerance with early fatiguability, pain, cramps and occasionally myoglobinuria. In two patients and in a mouse mutant with muscle Phk deficiency, mutations were previously found in the muscle isoform of the Phk alpha subunit, encoded by the X-chromosomal PHKA1 gene (MIM # 311870). No mutations have been identified in the muscle isoform of the Phk gamma subunit (PHKG1). In the present study, we determined Q1the structure of the PHKG1 gene and characterized its relationship to several pseudogenes. In six patients with adult- or juvenile-onset muscle glycogenosis and low Phk activity, we then searched for mutations in eight candidate genes. The coding sequences of all six genes that contribute to Phk in muscle were analysed: PHKA1, PHKB, PHKG1, CALM1, CALM2 and CALM3. We also analysed the genes of the muscle isoform of glycogen phosphorylase (PYGM), of a muscle-specific regulatory subunit of the AMP-dependent protein kinase (PRKAG3), and the promoter regions of PHKA1, PHKB and PHKG1. Only in one male patient did we find a PHKA1 missense mutation (D299V) that explains the enzyme deficiency. Two patients were heterozygous for single amino-acid replacements in PHKB that are of unclear significance (Q657K and Y770C). No sequence abnormalities were found in the other three patients. If these results can be generalized, only a fraction of cases with muscle glycogenosis and a biochemical diagnosis of low Phk activity are caused by coding, splice-site or promoter mutations in PHKA1, PHKG1 or other Phk subunit genes. Most patients with this diagnosis probably are affected either by elusive mutations of Phk subunit genes or by defects in other, unidentified genes.
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Affiliation(s)
- Barbara Burwinkel
- Institut für Physiologische Chemie, Ruhr-Universität Bochum, D-44780 Bochum, Germany
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Ban K, Sugiyama K, Goto K, Mizutani F, Togari H. Detection of PHKA2 gene mutation in four Japanese patients with hepatic phosphorylase kinase deficiency. TOHOKU J EXP MED 2003; 200:47-53. [PMID: 12862311 DOI: 10.1620/tjem.200.47] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
We analyzed the PHKA2 gene in four Japanese families with hepatic phosphorylase kinase (PhK) deficiency. Mutational analysis of PHKA2 cDNA was performed by reverse-transcribed polymerase chain reaction (RT-PCR) and direct sequencing, and each mutation was confirmed on the genomic DNA. In boys with low erythrocyte PhK activity (i.e., x-linked liver glycogenosis [XLG] type I), deletion of exon 2 (splice site mutation of 79-1 G > T) or nonsense mutation of Q1169X or R497X was identified. However, missense mutation of R295C was identified in one boy with normal erythrocyte PhK activity (i.e., XLG type II). This mutation was not found in 100 control alleles, and was considered responsible for presentation of the XLG type II phenotype. Excluding Q1169X, all mutations detected in this study represented novel mutations. All mothers were found to be heterozygous carriers of the mutations. Gene analysis was confirmed to represent a useful procedure for diagnosing XLG type II, for which liver biopsy had previously been required to detect hepatic PhK deficiency.
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Affiliation(s)
- Kyoko Ban
- Department of Pediatrics, Neonatology and Congenital Disorders, Nagoya City University, Graduate School of Medical Sciences, Nagoya 467-8601, Japan.
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Rudolfová J, Slovácková R, Trbusek M, Pesková K, St'astná S, Kozák L. Identification of three novel mutations in the PHKA2 gene in Czech patients with X-linked liver glycogenosis. J Inherit Metab Dis 2001; 24:85-7. [PMID: 11286390 DOI: 10.1023/a:1005635629149] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- J Rudolfová
- Department of Biochemical and Molecular Genetics, Research Institute of Child Health, Brno, Czech Republic
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Ayers NA, Wilkinson DA, Fitzgerald TJ, Carlson GM. Self-association of the alpha subunit of phosphorylase kinase as determined by two-hybrid screening. J Biol Chem 1999; 274:35583-90. [PMID: 10585434 DOI: 10.1074/jbc.274.50.35583] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The structural organization of the (alphabetagammadelta)(4) phosphorylase kinase complex has been studied using the yeast two-hybrid screen for the purpose of elucidating regions of alpha subunit interactions. By screening a rabbit skeletal muscle cDNA library with residues 1-1059 of the alpha subunit of phosphorylase kinase, we have isolated 16 interacting, independent, yet overlapping transcripts of the alpha subunit containing its C-terminal region. Domain mapping of binary interactions between alpha constructs revealed two regions involved in the self-association of the alpha subunit: residues 833-854, a previously unrecognized leucine zipper, and an unspecified region within residues 1015-1237. The cognate binding partner for the latter domain has been inferred to lie within the stretch from residues 864-1059. Indirect evidence from the literature suggests that the interacting domains contained within the latter two, overlapping regions may be further narrowed to the stretches from 1057 to 1237 and from 864 to 971. Cross-linking of the nonactivated holoenzyme with N-(gamma-maleimidobutyroxy)sulfosuccin-imide ester produced intramolecularly cross-linked alpha-alpha dimers, consistent with portions of two alpha subunits in the holoenyzme being in sufficient proximity to associate. This is the first report to identify potential areas of contact between the alpha subunits of phosphorylase kinase. Additionally, issues regarding the general utility of two-hybrid screening as a method for studying homodimeric interactions are discussed.
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Affiliation(s)
- N A Ayers
- Division of Molecular Biology, School of Biological Sciences, University of Missouri, Kansas City, Missouri 64110-2499, USA
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