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Kostopoulos G, Tzikos G, Sortsis A, Toulis K. Autosomal dominant pseudohypoparathyroidism type 1b due to STX16 deletion: a case presentation and literature review. Minerva Endocrinol (Torino) 2024; 49:217-225. [PMID: 35119251 DOI: 10.23736/s2724-6507.20.03233-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
INTRODUCTION Pseudohypoparathyroidism (PHP) is a heterogeneous group of rare, genetically related, endocrine disorders, characterized by end-organ resistance to parathyroid hormone (PTH) action and other G protein-coupled receptors (GPCRs) related hormones. The clinical variants of PHP are classified according to the presence of features of Albright's hereditary osteodystrophy (AHO) and in vivo response to exogenous PTH. Autosomal dominant PHP1b is often caused by a deletion in the syntaxin-16 (STX16) gene, leading to a loss of methylation in the A/B exon of the guanine nucleotide-binding protein a-stimulating polypeptide (GNAS) complex. Herein, we present a case of a 41-year-old man with familiar PHP1b due to a maternal inherited 3-kb STX16 deletion, who was referred to us for consultation by artificial reproductive technology specialists. EVIDENCE ACQUISITION A bibliographic search was performed in electronic databases (PubMed and Cochrane Library) to identify similar cases. EVIDENCE SYNTHESIS Twenty studies (case-series or reports) were eligible. These studies included collectively 120 patients; 46 patients (38.3%) presented with symptoms of hypocalcemia; 38 were asymptomatic (31.7%); data for 36 patients (30%) were unavailable. Thyroid-stimulating hormone (TSH) resistance was documented in 25 occasions (21%); growth hormone deficiency in 2 (1.7%); 3 patients shared features of the AHO (2.5%); 6 had abnormal bone mineral density test (5%). Notable is the development of tertiary hyperparathyroidism in 3 individuals (2.5%). CONCLUSIONS The present review confirms the heterogeneity in the clinical spectrum of familiar PHP1b. Future research should focus on the molecular characterization of the GNAS disorders, leading to a facile diagnosis and appropriate genetic counseling.
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Huang S, He Y, Lin X, Sun S, Zheng F. Clinical and genetic analysis of pseudohypoparathyroidism complicated by hypokalemia: a case report and review of the literature. BMC Endocr Disord 2022; 22:98. [PMID: 35410271 PMCID: PMC9004107 DOI: 10.1186/s12902-022-01011-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Accepted: 03/30/2022] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Pseudohypoparathyroidism (PHP) encompasses a highly heterogenous group of disorders, characterized by parathyroid hormone (PTH) resistance caused by mutations in the GNAS gene or other upstream targets. Here, we investigate the characteristics of a female patient diagnosed with PHP complicated with hypokalemia, and her family members. CASE PRESENTATION AND GENE ANALYSIS A 27-year-old female patient occasionally exhibited asymptomatic hypocalcemia and hypokalemia during her pregnancy 1 year ago. Seven months after delivery, she experienced tetany and dysphonia with diarrhea. Tetany symptoms were relieved after intravenous calcium gluconate supplementation and she was then transferred to our Hospital. Laboratory assessments of the patient revealed hypokalemia, hypocalcemia and hyperphosphatemia despite elevated PTH levels. CT scanning of the brain revealed globus pallidus calcification. Possible mutations in GNAS and hypokalemia related genes were identified using WES, exon copies of STX16 were analized by MLPA and the methylation status of GNAS in three differential methylated regions (DMRs) was analyzed by methylation-specific polymerase chain reaction, followed by confirmation with gene sequencing. The patient was clinically diagnosed with PHP-1b. Loss of methylation in the A/B region and hypermethylation in the NESP55 region were detected. No other mutations in GNAS or hypokalemia related genes and no deletions of STX16 exons were detected. A negative family history and abnormal DMRs in GNAS led to a diagnosis of sporadic PHP-1b of the patient. CONCLUSIONS Hypokalemia is a rare disorder associated with PHP-1b. Analysis of genetic and epigenetic mutations can aid in the diagnosis and accurate subtyping of PHP.
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Affiliation(s)
- Shaohan Huang
- Department of endocrinology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Yingzi He
- Department of endocrinology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Xihua Lin
- Department of endocrinology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Shuiya Sun
- Department of endocrinology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Fenping Zheng
- Department of endocrinology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
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Ramalho E Silva JD, da Rocha GFMA, Oliveira MJM. An intricate case of sporadic pseudohypoparathyroidism type 1B with a review of literature. ARCHIVES OF ENDOCRINOLOGY AND METABOLISM 2021; 65:112-116. [PMID: 33320452 PMCID: PMC10528691 DOI: 10.20945/2359-3997000000316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 09/17/2020] [Indexed: 11/23/2022]
Abstract
Pseudohypoparathyroidism comprehends an assorted group of genetically rare disorders that share end-organ resistance to parathyroid hormone. Genetic and epigenetic modifications on guanine nucleotide-binding protein alpha-stimulating gene locus are the most common underlying mechanisms associated with pseudohypoparathyroidism. Biochemical and molecular analysis stratify pseudohypoparathyroidism into types 1A, 1B, 1C, and 2. We describe an unusual case of sporadic pseudohypoparathyroidism type 1B. A 34-year-old Caucasian woman was admitted to the emergency department, with persistent asthenia, limb paresthesias, and tactile hyposensitivity. Her physical examination, previous personal and family histories were unsuspicious, except for mild, intermittent and self-limited complaints of paresthesia during her two pregnancies, but no detailed workup was done. No typical features of Albright hereditary osteodystrophy were observed. The initial laboratory investigation showed elevated parathyroid hormone level (311.2 pg/mL), hypocalcemia (albumin-corrected serum calcium 4.3 mg/dL), hypocalciuria, hyperphosphatemia, hypophosphaturia, and vitamin D deficiency. Combined calcium, vitamin D, and magnesium supplementation was commenced, with symptomatic and analytical improvement. Albeit resolution of vitamin D deficiency, the patient relapsed with mild and intermittent lower limb paresthesias. Pseudohypoparathyroidism was confirmed by molecular identification of the 3-kb STX16 deletion. The treatment was readjusted, and one year later, symptomatic remission was attained. Clinical and biochemical features, and their respective course, along with lack of distinctive features of Albright hereditary osteodystrophy pointed to pseudohypoparathyroidism type 1B. A careful follow-up is needed to avoid complications and recurrence. Once correction of hypocalcemia and hyperphosphatemia is achieved, with no reported complications and recurrence, a good prognosis is anticipated, comparable to the general population.
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Affiliation(s)
- José Diogo Ramalho E Silva
- Departamento de Endocrinologia e Nutrição, Centro Hospitalar de Vila Nova de Gaia/Espinho (CHVNG/E), Vila Nova de Gaia, Portugal,
| | | | - Maria João Martins Oliveira
- Departamento de Endocrinologia e Nutrição, Centro Hospitalar de Vila Nova de Gaia/Espinho (CHVNG/E), Vila Nova de Gaia, Portugal
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Danzig J, Li D, Jan de Beur S, Levine MA. High-throughput Molecular Analysis of Pseudohypoparathyroidism 1b Patients Reveals Novel Genetic and Epigenetic Defects. J Clin Endocrinol Metab 2021; 106:e4603-e4620. [PMID: 34157100 PMCID: PMC8677598 DOI: 10.1210/clinem/dgab460] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Indexed: 11/19/2022]
Abstract
CONTEXT Patients with pseudohypoparathyroidism type 1b (PHP1b) show disordered imprinting of the maternal GNAS allele or paternal uniparental disomy (UPD). Genetic deletions in STX16 or in upstream exons of GNAS are present in many familial but not sporadic cases. OBJECTIVE Characterization of epigenetic and genetic defects in patients with PHP1b. DESIGN AND PATIENTS DNA from 84 subjects, including 26 subjects with sporadic PHP1b, 27 affected subjects and 17 unaffected and/or obligate gene carriers from 12 PHP1b families, 11 healthy individuals, and 3 subjects with PHP1a was subjected to quantitative pyrosequencing of GNAS differentially methylated regions (DMRs), microarray analysis, and microsatellite haplotype analysis. SETTING Academic medical center. MAIN OUTCOME MEASUREMENTS Molecular pathology of PHP1b. RESULTS Healthy subjects, unaffected family members and obligate carriers of paternal PHP1b alleles, and subjects with PHP1a showed normal methylation of all DMRs. All PHP1b subjects showed loss of methylation (LOM) at the exon A/B DMR. Affected members of 9 PHP1b kindreds showed LOM only at the exon A/B DMR, which was associated with a 3-kb deletion of STX16 exons 4 through 6 in 7 families and a novel deletion of STX16 and adjacent NEPEPL1 in 1 family. A novel NESP deletion was found in 1 of 2 other families with more extensive methylation defects. One sporadic PHP1b had UPD of 20q, 2 had 3-kb STX16 deletions, and 5 had apparent epigenetic mosaicism. CONCLUSIONS We found diverse patterns of defective methylation and identified novel or previously known mutations in 9 of 12 PHP1b families.
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Affiliation(s)
- Jennifer Danzig
- Division of Endocrinology and Diabetes, and The Children’s Hospital of Philadelphia and Department of Pediatrics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Dong Li
- Center for Applied Genomics, The Children’s Hospital of Philadelphia and Department of Pediatrics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Suzanne Jan de Beur
- Division of Endocrinology and Metabolism, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Michael A Levine
- Division of Endocrinology and Diabetes, and The Children’s Hospital of Philadelphia and Department of Pediatrics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
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Abstract
Pseudohypoparathyroidism (PHP) and pseudopseudohypoparathyroidism (PPHP) are caused by mutations and/or epigenetic changes at the complex GNAS locus on chromosome 20q13.3 that undergoes parent-specific methylation changes at several differentially methylated regions (DMRs). GNAS encodes the alpha-subunit of the stimulatory G protein (Gsα) and several splice variants thereof. PHP type Ia (PHP1A) is caused by heterozygous inactivating mutations involving the maternal exons 1-13. Heterozygosity of these maternal GNAS mutations cause PTH-resistant hypocalcemia and hyperphosphatemia because paternal Gsα expression is suppressed in certain organs thus leading to little or no Gsα protein in the proximal renal tubules and other tissues. Besides biochemical abnormalities, PHP1A patients show developmental abnormalities, referred to as Albright's hereditary osteodystrophy (AHO). Some, but not all of these AHO features are encountered also in patients affected by PPHP, who carry paternal Gsα-specific mutations and typically show no laboratory abnormalities. Autosomal dominant PHP type Ib (AD-PHP1B) is caused by heterozygous maternal deletions within GNAS or STX16, which are associated with loss of methylation at the A/B DMR alone or at all maternally methylated GNAS exons. Loss of methylation of exon A/B and the resulting biallelic expression of A/B transcript reduces Gsα expression thus leading to hormonal resistance. Epigenetic changes at all differentially methylated GNAS regions are also observed in sporadic PHP1B, which is the most frequent PHP1B variant. However, this disease variant remains unresolved at the molecular level, except for rare cases with paternal uniparental isodisomy or heterodisomy of chromosome 20q (patUPD20q).
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Affiliation(s)
- Harald Jüppner
- Endocrine Unit, Department of Medicine and Pediatric Nephrology Unit, Department of Pediatrics, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
- Correspondence: Harald Jüppner, MD, Endocrine Unit, Thier 10, 50 Blossom Street, Massachusetts General Hospital, Boston, MA 02114, USA.
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Papadopoulou A, Bountouvi E, Karachaliou FE. The Molecular Basis of Calcium and Phosphorus Inherited Metabolic Disorders. Genes (Basel) 2021; 12:genes12050734. [PMID: 34068220 PMCID: PMC8153134 DOI: 10.3390/genes12050734] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 04/30/2021] [Accepted: 05/05/2021] [Indexed: 02/07/2023] Open
Abstract
Calcium (Ca) and Phosphorus (P) hold a leading part in many skeletal and extra-skeletal biological processes. Their tight normal range in serum mirrors their critical role in human well-being. The signalling “voyage” starts at Calcium Sensing Receptor (CaSR) localized on the surface of the parathyroid glands, which captures the “oscillations” of extracellular ionized Ca and transfers the signal downstream. Parathyroid hormone (PTH), Vitamin D, Fibroblast Growth Factor (FGF23) and other receptors or ion-transporters, work synergistically and establish a highly regulated signalling circuit between the bone, kidneys, and intestine to ensure the maintenance of Ca and P homeostasis. Any deviation from this well-orchestrated scheme may result in mild or severe pathologies expressed by biochemical and/or clinical features. Inherited disorders of Ca and P metabolism are rare. However, delayed diagnosis or misdiagnosis may cost patient’s quality of life or even life expectancy. Unravelling the thread of the molecular pathways involving Ca and P signaling, we can better understand the link between genetic alterations and biochemical and/or clinical phenotypes and help in diagnosis and early therapeutic intervention.
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Luo D, Qi X, Liu L, Su Y, Fang L, Guan Q. Genetic and Epigenetic Characteristics of Autosomal Dominant Pseudohypoparathyroidism Type 1B: Case Reports and Literature Review. Horm Metab Res 2021; 53:225-235. [PMID: 33513624 DOI: 10.1055/a-1341-9891] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Autosomal dominant pseudohypoparathyroidism 1B (AD-PHP1B) is a rare endocrine and imprinted disorder. The objective of this study is to clarify the imprinted regulation of the guanine nucleotide binding-protein α-stimulating activity polypeptide 1 (GNAS) cluster in the occurrence and development of AD-PHP1B based on animal and clinical patient studies. The methylation-specific multiples ligation-dependent probe amplification (MS-MLPA) was conducted to detect the copy number variation in syntaxin-16 (STX16) gene and methylation status of the GNAS differentially methylated regions (DMRs). Long-range PCR was used to confirm deletion at STX16 gene. In the first family, DNA analysis of the proband and proband's mother revealed an isolated loss of methylation (LOM) at exon A/B and a 3.0 kb STX16 deletion. The patient's healthy grandmother had the 3.0 kb STX16 deletion but no epigenetic abnormality. The patient's healthy maternal aunt showed no genetic or epigenetic abnormality. In the second family, the analysis of long-range PCR revealed the 3.0 kb STX16 deletion for the proband but not her children. In this study, 3.0 kb STX16 deletion causes isolated LOM at exon A/B in two families, which is the most common genetic mutation of AD-PHP1B. The deletion involving NESP55 or AS or genomic rearrangements of GNAS can also result in AD-PHP1B, but it's rare. LOM at exon A/B DMR is prerequisite methylation defect of AD-PHP1B. STX16 and NESP55 directly control the imprinting at exon A/B, while AS controls the imprinting at exon A/B by regulating the transcriptional level of NESP55.
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Affiliation(s)
- Dandan Luo
- Department of Endocrinology and Metabolism, Shandong University, Jinan, Shandong, China
- Shandong Provincial Key Laboratory of Endocrinology and Lipid Metabolism, Shandong Academy of Clinical Medicine, Jinan, Shandong, China
| | - Xiangyu Qi
- Department of Endocrinology and Metabolism, Shandong University, Jinan, Shandong, China
- Shandong Provincial Key Laboratory of Endocrinology and Lipid Metabolism, Shandong Academy of Clinical Medicine, Jinan, Shandong, China
| | - Luna Liu
- Department of Endocrinology and Metabolism, Shandong University, Jinan, Shandong, China
- Shandong Provincial Key Laboratory of Endocrinology and Lipid Metabolism, Shandong Academy of Clinical Medicine, Jinan, Shandong, China
| | - Yu Su
- Department of Endocrinology and Metabolism, Shandong University, Jinan, Shandong, China
- Shandong Provincial Key Laboratory of Endocrinology and Lipid Metabolism, Shandong Academy of Clinical Medicine, Jinan, Shandong, China
| | - Li Fang
- Shandong Provincial Key Laboratory of Endocrinology and Lipid Metabolism, Shandong Academy of Clinical Medicine, Jinan, Shandong, China
| | - Qingbo Guan
- Department of Endocrinology and Metabolism, Shandong University, Jinan, Shandong, China
- Shandong Provincial Key Laboratory of Endocrinology and Lipid Metabolism, Shandong Academy of Clinical Medicine, Jinan, Shandong, China
- Department of Endocrinology and Metabolism, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, China
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Tang BL. SNAREs and developmental disorders. J Cell Physiol 2020; 236:2482-2504. [PMID: 32959907 DOI: 10.1002/jcp.30067] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 08/20/2020] [Accepted: 09/09/2020] [Indexed: 12/12/2022]
Abstract
Members of the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) family mediate membrane fusion processes associated with vesicular trafficking and autophagy. SNAREs mediate core membrane fusion processes essential for all cells, but some SNAREs serve cell/tissue type-specific exocytic/endocytic functions, and are therefore critical for various aspects of embryonic development. Mutations or variants of their encoding genes could give rise to developmental disorders, such as those affecting the nervous system and immune system in humans. Mutations to components in the canonical synaptic vesicle fusion SNARE complex (VAMP2, STX1A/B, and SNAP25) and a key regulator of SNARE complex formation MUNC18-1, produce variant phenotypes of autism, intellectual disability, movement disorders, and epilepsy. STX11 and MUNC18-2 mutations underlie 2 subtypes of familial hemophagocytic lymphohistiocytosis. STX3 mutations contribute to variant microvillus inclusion disease. Chromosomal microdeletions involving STX16 play a role in pseudohypoparathyroidism type IB associated with abnormal imprinting of the GNAS complex locus. In this short review, I discuss these and other SNARE gene mutations and variants that are known to be associated with a variety developmental disorders, with a focus on their underlying cellular and molecular pathological basis deciphered through disease modeling. Possible pathogenic potentials of other SNAREs whose variants could be disease predisposing are also speculated upon.
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Affiliation(s)
- Bor L Tang
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
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Mantovani G, Bastepe M, Monk D, de Sanctis L, Thiele S, Ahmed SF, Bufo R, Choplin T, De Filippo G, Devernois G, Eggermann T, Elli FM, Ramirez AG, Germain-Lee EL, Groussin L, Hamdy NA, Hanna P, Hiort O, Jüppner H, Kamenický P, Knight N, Le Norcy E, Lecumberri B, Levine MA, Mäkitie O, Martin R, Martos-Moreno GÁ, Minagawa M, Murray P, Pereda A, Pignolo R, Rejnmark L, Rodado R, Rothenbuhler A, Saraff V, Shoemaker AH, Shore EM, Silve C, Turan S, Woods P, Zillikens MC, de Nanclares GP, Linglart A. Recommendations for Diagnosis and Treatment of Pseudohypoparathyroidism and Related Disorders: An Updated Practical Tool for Physicians and Patients. Horm Res Paediatr 2020; 93:182-196. [PMID: 32756064 PMCID: PMC8140671 DOI: 10.1159/000508985] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 05/21/2020] [Indexed: 12/12/2022] Open
Abstract
Patients affected by pseudohypoparathyroidism (PHP) or related disorders are characterized by physical findings that may include brachydactyly, a short stature, a stocky build, early-onset obesity, ectopic ossifications, and neurodevelopmental deficits, as well as hormonal resistance most prominently to parathyroid hormone (PTH). In addition to these alterations, patients may develop other hormonal resistances, leading to overt or subclinical hypothyroidism, hypogonadism and growth hormone (GH) deficiency, impaired growth without measurable evidence for hormonal abnormalities, type 2 diabetes, and skeletal issues with potentially severe limitation of mobility. PHP and related disorders are primarily clinical diagnoses. Given the variability of the clinical, radiological, and biochemical presentation, establishment of the molecular diagnosis is of critical importance for patients. It facilitates management, including prevention of complications, screening and treatment of endocrine deficits, supportive measures, and appropriate genetic counselling. Based on the first international consensus statement for these disorders, this article provides an updated and ready-to-use tool to help physicians and patients outlining relevant interventions and their timing. A life-long coordinated and multidisciplinary approach is recommended, starting as far as possible in early infancy and continuing throughout adulthood with an appropriate and timely transition from pediatric to adult care.
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Affiliation(s)
- Giovanna Mantovani
- Endocrinology Unit, Department of Clinical Sciences and Community Health, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, University of Milan, Milan, Italy
| | - Murat Bastepe
- Endocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - David Monk
- Biomedical Research Centre, University of East Anglia, Norwich Research Park, Norwich, UK
| | - Luisa de Sanctis
- Pediatric Endocrinology Unit, Department of Public Health and Pediatric Sciences, University of Torino, Torino, Italy
| | - Susanne Thiele
- Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics, University of Lübeck, Lübeck, Germany
| | - S. Faisal Ahmed
- Developmental Endocrinology Research Group, School of Medicine, Dentistry and Nursing, University of Glasgow, Glasgow, UK
| | - Roberto Bufo
- Italian Progressive Osseous Heteroplasia Association (IPOHA), Foggia, Italy
| | - Timothée Choplin
- K20, French PHP and Related Disorders Patient Association, Jouars-Pontchartrain, France
| | - Gianpaolo De Filippo
- APHP, Department of Medicine for Adolescents, Bicêtre Paris Saclay Hospital (HUPS), Le Kremlin-Bicetre, France
| | - Guillemette Devernois
- K20, French PHP and Related Disorders Patient Association, Jouars-Pontchartrain, France
| | - Thomas Eggermann
- Institute of Human Genetics, Medical Faculty, RWTH Aachen University, Aachen, Germany
| | - Francesca M. Elli
- Endocrinology Unit, Department of Clinical Sciences and Community Health, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, University of Milan, Milan, Italy
| | | | - Emily L. Germain-Lee
- Albright Center and Center for Rare Bone Disorders, Division of Pediatric Endocrinology and Diabetes, Connecticut Children’s Medical Center, Farmington, CT, USA,Department of Pediatrics, University of Connecticut School of Medicine, Farmington, CT, USA
| | - Lionel Groussin
- APHP, Department of Endocrinology, Cochin Hospital (HUPC), Paris, France,University of Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Neveen A.T. Hamdy
- Division of Endocrinology and Centre for Bone Quality, Department of Medicine, Leiden University Medical Center, Leiden, The Netherlands
| | - Patrick Hanna
- INSERM U1185, Bicêtre Paris Sud – Paris Saclay University, Le Kremlin-Bicêtre, France
| | - Olaf Hiort
- Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics, University of Lübeck, Lübeck, Germany
| | - Harald Jüppner
- Endocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Peter Kamenický
- INSERM U1185, Bicêtre Paris Sud – Paris Saclay University, Le Kremlin-Bicêtre, France,APHP, Reference Center for Rare Disorders of Calcium and Phosphate Metabolism, Platform of Expertise Paris-Saclay for Rare Diseases and Filière OSCAR, Bicêtre Paris Saclay Hospital (HUPS), Le Kremlin-Bicêtre, France,APHP, Department of Endocrinology and Reproductive Diseases, Bicêtre Paris Saclay Hospital (HUPS), Le Kremlin-Bicêtre, France
| | - Nina Knight
- Acrodysostosis Support and Research patients’ group, London, UK
| | - Elvire Le Norcy
- University of Paris Descartes, Sorbonne Paris Cité, Paris, France,APHP, Department of Odontology, Bretonneau Hospital (PNVS), Paris, France
| | - Beatriz Lecumberri
- Department of Endocrinology and Nutrition, La Paz University Hospital, Madrid, Spain,Department of Medicine, Autonomous University of Madrid (UAM), Madrid, Spain,Hospital La Paz Institute for Health Research (IdiPAZ), Madrid, Spain
| | - Michael A. Levine
- Division of Endocrinology and Diabetes and Center for Bone Health, Children’s Hospital of Philadelphia, Philadelphia, PA, USA,Department of Pediatrics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Outi Mäkitie
- Children’s Hospital, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Regina Martin
- Osteometabolic Disorders Unit, Hormone and Molecular Genetics Laboratory (LIM/42), Endocrinology Division, Hospital das Clínicas HCFMUSP, Faculty of Medicine, University of Sao Paulo, Sao Paulo, Brazil
| | - Gabriel Ángel Martos-Moreno
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Hospital La Princesa Institute for Health Research (IIS La Princesa), Madrid, Spain,Department of Pediatrics, Autonomous University of Madrid (UAM), Madrid, Spain,CIBERobn, Instituto de Salud Carlos III, Madrid, Spain
| | | | - Philip Murray
- Department of Paediatric Endocrinology, Royal Manchester Children’s Hospital, Manchester University NHS Foundation Trust, Manchester, UK
| | - Arrate Pereda
- Molecular (Epi)Genetics Laboratory, BioAraba Research Health Institute, Araba University Hospital-Txagorritxu, Vitoria-Gasteiz, Spain
| | | | - Lars Rejnmark
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Rebeca Rodado
- AEPHP, Spanish PHP and Related Disorders Patient Association, Almeria, Spain
| | - Anya Rothenbuhler
- APHP, Reference Center for Rare Disorders of Calcium and Phosphate Metabolism, Platform of Expertise Paris-Saclay for Rare Diseases and Filière OSCAR, Bicêtre Paris Saclay Hospital (HUPS), Le Kremlin-Bicêtre, France,APHP, Endocrinology and Diabetes for Children, Bicêtre Paris Saclay Hospital (HUPS), Le Kremlin-Bicêtre, France
| | - Vrinda Saraff
- Department of Endocrinology and Diabetes, Birmingham Children’s Hospital, Birmingham, UK
| | - Ashley H. Shoemaker
- Pediatric Endocrinology and Diabetes, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Eileen M. Shore
- Departments of Orthopedic Surgery and Genetics, Center for Research in FOP and Related Disorders, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Caroline Silve
- APHP, Service de Biochimie et Génétique Moléculaires, Hôpital Cochin, Paris, France
| | - Serap Turan
- Department of Pediatrics, Division of Endocrinology and Diabetes, Marmara University, Istanbul, Turkey
| | - Philip Woods
- Acrodysostosis Support and Research patients’ group, London, UK
| | - M. Carola Zillikens
- Department of Internal Medicine, Bone Center Erasmus MC – University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Guiomar Perez de Nanclares
- Molecular (Epi)Genetics Laboratory, BioAraba Research Health Institute, Araba University Hospital-Txagorritxu, Vitoria-Gasteiz, Spain
| | - Agnès Linglart
- INSERM U1185, Bicêtre Paris Sud – Paris Saclay University, Le Kremlin-Bicêtre, France,APHP, Reference Center for Rare Disorders of Calcium and Phosphate Metabolism, Platform of Expertise Paris-Saclay for Rare Diseases and Filière OSCAR, Bicêtre Paris Saclay Hospital (HUPS), Le Kremlin-Bicêtre, France,APHP, Endocrinology and Diabetes for Children, Bicêtre Paris Saclay Hospital (HUPS), Le Kremlin-Bicêtre, France
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Mantovani G, Bastepe M, Monk D, de Sanctis L, Thiele S, Usardi A, Ahmed SF, Bufo R, Choplin T, De Filippo G, Devernois G, Eggermann T, Elli FM, Freson K, García Ramirez A, Germain-Lee EL, Groussin L, Hamdy N, Hanna P, Hiort O, Jüppner H, Kamenický P, Knight N, Kottler ML, Le Norcy E, Lecumberri B, Levine MA, Mäkitie O, Martin R, Martos-Moreno GÁ, Minagawa M, Murray P, Pereda A, Pignolo R, Rejnmark L, Rodado R, Rothenbuhler A, Saraff V, Shoemaker AH, Shore EM, Silve C, Turan S, Woods P, Zillikens MC, Perez de Nanclares G, Linglart A. Diagnosis and management of pseudohypoparathyroidism and related disorders: first international Consensus Statement. Nat Rev Endocrinol 2018; 14:476-500. [PMID: 29959430 PMCID: PMC6541219 DOI: 10.1038/s41574-018-0042-0] [Citation(s) in RCA: 184] [Impact Index Per Article: 30.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
This Consensus Statement covers recommendations for the diagnosis and management of patients with pseudohypoparathyroidism (PHP) and related disorders, which comprise metabolic disorders characterized by physical findings that variably include short bones, short stature, a stocky build, early-onset obesity and ectopic ossifications, as well as endocrine defects that often include resistance to parathyroid hormone (PTH) and TSH. The presentation and severity of PHP and its related disorders vary between affected individuals with considerable clinical and molecular overlap between the different types. A specific diagnosis is often delayed owing to lack of recognition of the syndrome and associated features. The participants in this Consensus Statement agreed that the diagnosis of PHP should be based on major criteria, including resistance to PTH, ectopic ossifications, brachydactyly and early-onset obesity. The clinical and laboratory diagnosis should be confirmed by a molecular genetic analysis. Patients should be screened at diagnosis and during follow-up for specific features, such as PTH resistance, TSH resistance, growth hormone deficiency, hypogonadism, skeletal deformities, oral health, weight gain, glucose intolerance or type 2 diabetes mellitus, and hypertension, as well as subcutaneous and/or deeper ectopic ossifications and neurocognitive impairment. Overall, a coordinated and multidisciplinary approach from infancy through adulthood, including a transition programme, should help us to improve the care of patients affected by these disorders.
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Affiliation(s)
- Giovanna Mantovani
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Endocrinology Unit, Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Murat Bastepe
- Endocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - David Monk
- Imprinting and Cancer Group, Cancer Epigenetic and Biology Program (PEBC), Institut d'Investigació Biomedica de Bellvitge (IDIBELL), Barcelona, Spain
| | - Luisa de Sanctis
- Pediatric Endocrinology Unit, Department of Public Health and Pediatric Sciences, University of Torino, Turin, Italy
| | - Susanne Thiele
- Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics, University of Lübeck, Lübeck, Germany
| | - Alessia Usardi
- APHP, Reference Center for Rare Disorders of Calcium and Phosphate Metabolism, Platform of Expertise Paris-Sud for Rare Diseases and Filière OSCAR, Bicêtre Paris Sud Hospital (HUPS), Le Kremlin-Bicêtre, France
- APHP, Endocrinology and diabetes for children, Bicêtre Paris Sud Hospital (HUPS), Le Kremlin-Bicêtre, France
| | - S Faisal Ahmed
- Developmental Endocrinology Research Group, School of Medicine, Dentistry and Nursing, University of Glasgow, Glasgow, UK
| | - Roberto Bufo
- IPOHA, Italian Progressive Osseous Heteroplasia Association, Cerignola, Foggia, Italy
| | - Timothée Choplin
- K20, French PHP and related disorders patient association, Jouars Pontchartrain, France
| | - Gianpaolo De Filippo
- APHP, Department of medicine for adolescents, Bicêtre Paris Sud Hospital (HUPS), Le Kremlin-Bicêtre, France
| | - Guillemette Devernois
- K20, French PHP and related disorders patient association, Jouars Pontchartrain, France
| | - Thomas Eggermann
- Institute of Human Genetics, Medical Faculty, RWTH Aachen University, Aachen, Germany
| | - Francesca M Elli
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Endocrinology Unit, Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Kathleen Freson
- Department of Cardiovascular Sciences, Center for Molecular and Vascular Biology, Gasthuisberg, University of Leuven, Leuven, Belgium
| | - Aurora García Ramirez
- AEPHP, Spanish PHP and related disorders patient association, Huércal-Overa, Almería, Spain
| | - Emily L Germain-Lee
- Albright Center & Center for Rare Bone Disorders, Division of Pediatric Endocrinology & Diabetes, Connecticut Children's Medical Center, Farmington, CT, USA
- Department of Pediatrics, University of Connecticut School of Medicine, Farmington, CT, USA
| | - Lionel Groussin
- APHP, Department of Endocrinology, Cochin Hospital (HUPC), Paris, France
- University of Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Neveen Hamdy
- Department of Medicine, Division of Endocrinology and Centre for Bone Quality, Leiden University Medical Center, Leiden, Netherlands
| | - Patrick Hanna
- INSERM U1169, Bicêtre Paris Sud, Paris Sud - Paris Saclay University, Le Kremlin-Bicêtre, France
| | - Olaf Hiort
- Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics, University of Lübeck, Lübeck, Germany
| | - Harald Jüppner
- Endocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Peter Kamenický
- APHP, Reference Center for Rare Disorders of Calcium and Phosphate Metabolism, Platform of Expertise Paris-Sud for Rare Diseases and Filière OSCAR, Bicêtre Paris Sud Hospital (HUPS), Le Kremlin-Bicêtre, France
- APHP, Department of Endocrinology and Reproductive Diseases, Bicêtre Paris Sud Hospital (HUPS), Le Kremlin-Bicêtre, France
- INSERM U1185, Paris Sud - Paris Saclay University, Le Kremlin-Bicêtre, France
| | - Nina Knight
- UK acrodysostosis patients' group, London, UK
| | - Marie-Laure Kottler
- Department of Genetics, Reference Centre for Rare Disorders of Calcium and Phosphate Metabolism, Caen University Hospital, Caen, France
- BIOTARGEN, UNICAEN, Normandie University, Caen, France
| | - Elvire Le Norcy
- University of Paris Descartes, Sorbonne Paris Cité, Paris, France
- APHP, Department of Odontology, Bretonneau Hospital (PNVS), Paris, France
| | - Beatriz Lecumberri
- Department of Endocrinology and Nutrition, La Paz University Hospital, Madrid, Spain
- Department of Medicine, Autonomous University of Madrid (UAM), Madrid, Spain
- Endocrine Diseases Research Group, Hospital La Paz Institute for Health Research (IdiPAZ), Madrid, Spain
| | - Michael A Levine
- Division of Endocrinology and Diabetes and Center for Bone Health, Children's Hospital of Philadelphia and Department of Pediatrics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Outi Mäkitie
- Children's Hospital, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Regina Martin
- Osteometabolic Disorders Unit, Hormone and Molecular Genetics Laboratory (LIM/42), Endocrinology Division, Hospital das Clínicas HCFMUSP, Faculty of Medicine, University of Sao Paulo, Sao Paulo, Brazil
| | - Gabriel Ángel Martos-Moreno
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, CIBERobn, ISCIII, Madrid, Spain
- Department of Pediatrics, Autonomous University of Madrid (UAM), Madrid, Spain
- Endocrine Diseases Research Group, Hospital La Princesa Institute for Health Research (IIS La Princesa), Madrid, Spain
| | | | - Philip Murray
- Department of Paediatric Endocrinology, Royal Manchester Children's Hospital, Manchester University NHS Foundation Trust, Manchester, UK
| | - Arrate Pereda
- Molecular (Epi)Genetics Laboratory, BioAraba National Health Institute, Hospital Universitario Araba-Txagorritxu, Vitoria-Gasteiz, Alava, Spain
| | | | - Lars Rejnmark
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Rebecca Rodado
- AEPHP, Spanish PHP and related disorders patient association, Huércal-Overa, Almería, Spain
| | - Anya Rothenbuhler
- APHP, Reference Center for Rare Disorders of Calcium and Phosphate Metabolism, Platform of Expertise Paris-Sud for Rare Diseases and Filière OSCAR, Bicêtre Paris Sud Hospital (HUPS), Le Kremlin-Bicêtre, France
- APHP, Endocrinology and diabetes for children, Bicêtre Paris Sud Hospital (HUPS), Le Kremlin-Bicêtre, France
| | - Vrinda Saraff
- Department of Endocrinology and Diabetes, Birmingham Children's Hospital, Birmingham, UK
| | - Ashley H Shoemaker
- Pediatric Endocrinology and Diabetes, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Eileen M Shore
- Departments of Orthopaedic Surgery and Genetics, Center for Research in FOP and Related Disorders, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Caroline Silve
- APHP, Service de Biochimie et Génétique Moléculaires, Hôpital Cochin, Paris, France
| | - Serap Turan
- Department of Pediatrics, Division of Endocrinology and Diabetes, Marmara University, Istanbul, Turkey
| | | | - M Carola Zillikens
- Department of Internal Medicine, Bone Center Erasmus MC - University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Guiomar Perez de Nanclares
- Molecular (Epi)Genetics Laboratory, BioAraba National Health Institute, Hospital Universitario Araba-Txagorritxu, Vitoria-Gasteiz, Alava, Spain.
| | - Agnès Linglart
- APHP, Reference Center for Rare Disorders of Calcium and Phosphate Metabolism, Platform of Expertise Paris-Sud for Rare Diseases and Filière OSCAR, Bicêtre Paris Sud Hospital (HUPS), Le Kremlin-Bicêtre, France.
- APHP, Endocrinology and diabetes for children, Bicêtre Paris Sud Hospital (HUPS), Le Kremlin-Bicêtre, France.
- INSERM U1169, Bicêtre Paris Sud, Paris Sud - Paris Saclay University, Le Kremlin-Bicêtre, France.
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Matta-Coelho C, Mesquita J, Souto SB. Pseudohypoparathyroidism Type 1B with Asymptomatic Hypocalcemia. AACE Clin Case Rep 2018. [DOI: 10.4158/accr-2017-0064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Elli FM, Linglart A, Garin I, de Sanctis L, Bordogna P, Grybek V, Pereda A, Giachero F, Verrua E, Hanna P, Mantovani G, Perez de Nanclares G. The Prevalence of GNAS Deficiency-Related Diseases in a Large Cohort of Patients Characterized by the EuroPHP Network. J Clin Endocrinol Metab 2016; 101:3657-3668. [PMID: 27428667 DOI: 10.1210/jc.2015-4310] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
CONTEXT The term pseudohypoparathyroidism (PHP) was coined to describe the clinical condition resulting from end-organ resistance to parathormone (rPTH), caused by genetic and/or epigenetic alterations within or upstream of GNAS. Although knowledge about PHP is growing, there are few data on the prevalence of underlying molecular defects. OBJECTIVE The purpose of our study was to ascertain the relative prevalence of PHP-associated molecular defects. DESIGN With a specially designed questionnaire, we collected data from all patients (n = 407) clinically and molecularly characterized to date by expert referral centers in France, Italy, and Spain. RESULTS Isolated rPTH (126/407, 31%) was caused only by epigenetic defects, 70% of patients showing loss of imprinting affecting all four GNAS differentially methylated regions and 30% loss of methylation restricted to the GNAS A/B:TSS-DMR. Multihormone resistance with no Albright's hereditary osteodystrophy (AHO) signs (61/407, 15%) was essentially due to epigenetic defects, although 10% of patients had point mutations. In patients with rPTH and AHO (40/407, 10%), the rate of point mutations was higher (28%) and methylation defects lower (about 70%). In patients with multihormone resistance and AHO (155/407, 38%), all types of molecular defects appeared with different frequencies. Finally, isolated AHO (18/407, 4%) and progressive osseous heteroplasia (7/407, 2%) were exclusively caused by point mutations. CONCLUSION With European data, we have established the prevalence of various genetic and epigenetic lesions in PHP-affected patients. Using these findings, we will develop objective criteria to guide cost-effective strategies for genetic testing and explore the implications for management and prognosis.
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Affiliation(s)
- Francesca Marta Elli
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico (F.M.E., E.V., P.B., G.M.), Department of Clinical Sciences and Community Health, University of Milan, Endocrinology and Diabetology Unit, Milan, Italy; APHP (A.L., V.G., P.H.), Reference Center for Rare Disorders of the Mineral Metabolism and Plateforme d'expertise Paris Sud Maladies Rares, Le Kremlin Bicêtre, France; INSERM U1169 (A.L., V.G., P.H.), Hôpital Bicêtre, Le Kremlin Bicêtre, et Université Paris-Saclay, France; Molecular (Epi)Genetics Laboratory (I.G., A.P., G.P.d.N.), BioAraba National Health Institute, Hospital Universitario Araba-Txagorritxu, Vitoria-Gasteiz, Spain; Department of Public Health and Pediatrics (L.d.S., F.G.), University of Turin, Regina Margherita Children's Hospital, Health and Science City, Turin, Italy; Department of Biochemistry and Molecular Biology (A.P.), University of Basque Country, Leioa, Spain
| | - Agnès Linglart
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico (F.M.E., E.V., P.B., G.M.), Department of Clinical Sciences and Community Health, University of Milan, Endocrinology and Diabetology Unit, Milan, Italy; APHP (A.L., V.G., P.H.), Reference Center for Rare Disorders of the Mineral Metabolism and Plateforme d'expertise Paris Sud Maladies Rares, Le Kremlin Bicêtre, France; INSERM U1169 (A.L., V.G., P.H.), Hôpital Bicêtre, Le Kremlin Bicêtre, et Université Paris-Saclay, France; Molecular (Epi)Genetics Laboratory (I.G., A.P., G.P.d.N.), BioAraba National Health Institute, Hospital Universitario Araba-Txagorritxu, Vitoria-Gasteiz, Spain; Department of Public Health and Pediatrics (L.d.S., F.G.), University of Turin, Regina Margherita Children's Hospital, Health and Science City, Turin, Italy; Department of Biochemistry and Molecular Biology (A.P.), University of Basque Country, Leioa, Spain
| | - Intza Garin
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico (F.M.E., E.V., P.B., G.M.), Department of Clinical Sciences and Community Health, University of Milan, Endocrinology and Diabetology Unit, Milan, Italy; APHP (A.L., V.G., P.H.), Reference Center for Rare Disorders of the Mineral Metabolism and Plateforme d'expertise Paris Sud Maladies Rares, Le Kremlin Bicêtre, France; INSERM U1169 (A.L., V.G., P.H.), Hôpital Bicêtre, Le Kremlin Bicêtre, et Université Paris-Saclay, France; Molecular (Epi)Genetics Laboratory (I.G., A.P., G.P.d.N.), BioAraba National Health Institute, Hospital Universitario Araba-Txagorritxu, Vitoria-Gasteiz, Spain; Department of Public Health and Pediatrics (L.d.S., F.G.), University of Turin, Regina Margherita Children's Hospital, Health and Science City, Turin, Italy; Department of Biochemistry and Molecular Biology (A.P.), University of Basque Country, Leioa, Spain
| | - Luisa de Sanctis
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico (F.M.E., E.V., P.B., G.M.), Department of Clinical Sciences and Community Health, University of Milan, Endocrinology and Diabetology Unit, Milan, Italy; APHP (A.L., V.G., P.H.), Reference Center for Rare Disorders of the Mineral Metabolism and Plateforme d'expertise Paris Sud Maladies Rares, Le Kremlin Bicêtre, France; INSERM U1169 (A.L., V.G., P.H.), Hôpital Bicêtre, Le Kremlin Bicêtre, et Université Paris-Saclay, France; Molecular (Epi)Genetics Laboratory (I.G., A.P., G.P.d.N.), BioAraba National Health Institute, Hospital Universitario Araba-Txagorritxu, Vitoria-Gasteiz, Spain; Department of Public Health and Pediatrics (L.d.S., F.G.), University of Turin, Regina Margherita Children's Hospital, Health and Science City, Turin, Italy; Department of Biochemistry and Molecular Biology (A.P.), University of Basque Country, Leioa, Spain
| | - Paolo Bordogna
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico (F.M.E., E.V., P.B., G.M.), Department of Clinical Sciences and Community Health, University of Milan, Endocrinology and Diabetology Unit, Milan, Italy; APHP (A.L., V.G., P.H.), Reference Center for Rare Disorders of the Mineral Metabolism and Plateforme d'expertise Paris Sud Maladies Rares, Le Kremlin Bicêtre, France; INSERM U1169 (A.L., V.G., P.H.), Hôpital Bicêtre, Le Kremlin Bicêtre, et Université Paris-Saclay, France; Molecular (Epi)Genetics Laboratory (I.G., A.P., G.P.d.N.), BioAraba National Health Institute, Hospital Universitario Araba-Txagorritxu, Vitoria-Gasteiz, Spain; Department of Public Health and Pediatrics (L.d.S., F.G.), University of Turin, Regina Margherita Children's Hospital, Health and Science City, Turin, Italy; Department of Biochemistry and Molecular Biology (A.P.), University of Basque Country, Leioa, Spain
| | - Virginie Grybek
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico (F.M.E., E.V., P.B., G.M.), Department of Clinical Sciences and Community Health, University of Milan, Endocrinology and Diabetology Unit, Milan, Italy; APHP (A.L., V.G., P.H.), Reference Center for Rare Disorders of the Mineral Metabolism and Plateforme d'expertise Paris Sud Maladies Rares, Le Kremlin Bicêtre, France; INSERM U1169 (A.L., V.G., P.H.), Hôpital Bicêtre, Le Kremlin Bicêtre, et Université Paris-Saclay, France; Molecular (Epi)Genetics Laboratory (I.G., A.P., G.P.d.N.), BioAraba National Health Institute, Hospital Universitario Araba-Txagorritxu, Vitoria-Gasteiz, Spain; Department of Public Health and Pediatrics (L.d.S., F.G.), University of Turin, Regina Margherita Children's Hospital, Health and Science City, Turin, Italy; Department of Biochemistry and Molecular Biology (A.P.), University of Basque Country, Leioa, Spain
| | - Arrate Pereda
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico (F.M.E., E.V., P.B., G.M.), Department of Clinical Sciences and Community Health, University of Milan, Endocrinology and Diabetology Unit, Milan, Italy; APHP (A.L., V.G., P.H.), Reference Center for Rare Disorders of the Mineral Metabolism and Plateforme d'expertise Paris Sud Maladies Rares, Le Kremlin Bicêtre, France; INSERM U1169 (A.L., V.G., P.H.), Hôpital Bicêtre, Le Kremlin Bicêtre, et Université Paris-Saclay, France; Molecular (Epi)Genetics Laboratory (I.G., A.P., G.P.d.N.), BioAraba National Health Institute, Hospital Universitario Araba-Txagorritxu, Vitoria-Gasteiz, Spain; Department of Public Health and Pediatrics (L.d.S., F.G.), University of Turin, Regina Margherita Children's Hospital, Health and Science City, Turin, Italy; Department of Biochemistry and Molecular Biology (A.P.), University of Basque Country, Leioa, Spain
| | - Federica Giachero
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico (F.M.E., E.V., P.B., G.M.), Department of Clinical Sciences and Community Health, University of Milan, Endocrinology and Diabetology Unit, Milan, Italy; APHP (A.L., V.G., P.H.), Reference Center for Rare Disorders of the Mineral Metabolism and Plateforme d'expertise Paris Sud Maladies Rares, Le Kremlin Bicêtre, France; INSERM U1169 (A.L., V.G., P.H.), Hôpital Bicêtre, Le Kremlin Bicêtre, et Université Paris-Saclay, France; Molecular (Epi)Genetics Laboratory (I.G., A.P., G.P.d.N.), BioAraba National Health Institute, Hospital Universitario Araba-Txagorritxu, Vitoria-Gasteiz, Spain; Department of Public Health and Pediatrics (L.d.S., F.G.), University of Turin, Regina Margherita Children's Hospital, Health and Science City, Turin, Italy; Department of Biochemistry and Molecular Biology (A.P.), University of Basque Country, Leioa, Spain
| | - Elisa Verrua
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico (F.M.E., E.V., P.B., G.M.), Department of Clinical Sciences and Community Health, University of Milan, Endocrinology and Diabetology Unit, Milan, Italy; APHP (A.L., V.G., P.H.), Reference Center for Rare Disorders of the Mineral Metabolism and Plateforme d'expertise Paris Sud Maladies Rares, Le Kremlin Bicêtre, France; INSERM U1169 (A.L., V.G., P.H.), Hôpital Bicêtre, Le Kremlin Bicêtre, et Université Paris-Saclay, France; Molecular (Epi)Genetics Laboratory (I.G., A.P., G.P.d.N.), BioAraba National Health Institute, Hospital Universitario Araba-Txagorritxu, Vitoria-Gasteiz, Spain; Department of Public Health and Pediatrics (L.d.S., F.G.), University of Turin, Regina Margherita Children's Hospital, Health and Science City, Turin, Italy; Department of Biochemistry and Molecular Biology (A.P.), University of Basque Country, Leioa, Spain
| | - Patrick Hanna
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico (F.M.E., E.V., P.B., G.M.), Department of Clinical Sciences and Community Health, University of Milan, Endocrinology and Diabetology Unit, Milan, Italy; APHP (A.L., V.G., P.H.), Reference Center for Rare Disorders of the Mineral Metabolism and Plateforme d'expertise Paris Sud Maladies Rares, Le Kremlin Bicêtre, France; INSERM U1169 (A.L., V.G., P.H.), Hôpital Bicêtre, Le Kremlin Bicêtre, et Université Paris-Saclay, France; Molecular (Epi)Genetics Laboratory (I.G., A.P., G.P.d.N.), BioAraba National Health Institute, Hospital Universitario Araba-Txagorritxu, Vitoria-Gasteiz, Spain; Department of Public Health and Pediatrics (L.d.S., F.G.), University of Turin, Regina Margherita Children's Hospital, Health and Science City, Turin, Italy; Department of Biochemistry and Molecular Biology (A.P.), University of Basque Country, Leioa, Spain
| | - Giovanna Mantovani
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico (F.M.E., E.V., P.B., G.M.), Department of Clinical Sciences and Community Health, University of Milan, Endocrinology and Diabetology Unit, Milan, Italy; APHP (A.L., V.G., P.H.), Reference Center for Rare Disorders of the Mineral Metabolism and Plateforme d'expertise Paris Sud Maladies Rares, Le Kremlin Bicêtre, France; INSERM U1169 (A.L., V.G., P.H.), Hôpital Bicêtre, Le Kremlin Bicêtre, et Université Paris-Saclay, France; Molecular (Epi)Genetics Laboratory (I.G., A.P., G.P.d.N.), BioAraba National Health Institute, Hospital Universitario Araba-Txagorritxu, Vitoria-Gasteiz, Spain; Department of Public Health and Pediatrics (L.d.S., F.G.), University of Turin, Regina Margherita Children's Hospital, Health and Science City, Turin, Italy; Department of Biochemistry and Molecular Biology (A.P.), University of Basque Country, Leioa, Spain
| | - Guiomar Perez de Nanclares
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico (F.M.E., E.V., P.B., G.M.), Department of Clinical Sciences and Community Health, University of Milan, Endocrinology and Diabetology Unit, Milan, Italy; APHP (A.L., V.G., P.H.), Reference Center for Rare Disorders of the Mineral Metabolism and Plateforme d'expertise Paris Sud Maladies Rares, Le Kremlin Bicêtre, France; INSERM U1169 (A.L., V.G., P.H.), Hôpital Bicêtre, Le Kremlin Bicêtre, et Université Paris-Saclay, France; Molecular (Epi)Genetics Laboratory (I.G., A.P., G.P.d.N.), BioAraba National Health Institute, Hospital Universitario Araba-Txagorritxu, Vitoria-Gasteiz, Spain; Department of Public Health and Pediatrics (L.d.S., F.G.), University of Turin, Regina Margherita Children's Hospital, Health and Science City, Turin, Italy; Department of Biochemistry and Molecular Biology (A.P.), University of Basque Country, Leioa, Spain
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de Lange IM, Verrijn Stuart AA, van der Luijt RB, Ploos van Amstel HK, van Haelst MM. Macrosomia, obesity, and macrocephaly as first clinical presentation of PHP1b caused by STX16 deletion. Am J Med Genet A 2016; 170:2431-5. [PMID: 27338644 DOI: 10.1002/ajmg.a.37818] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Accepted: 06/12/2016] [Indexed: 01/21/2023]
Abstract
Pseudohypoparathyroidism (PHP) is a genetic disorder with resistance to parathyroid hormone (PTH) as most important feature. Main subtypes of the disease are pseudohypoparathyroidism 1b (PHP1b) and pseudohypoparathyroidism 1a (PHP1a). PHP1b is characterized by PTH resistance of the renal cortex due to reduced activity of the stimulatory G protein α subunit (Gsα) of the PTH receptor. In addition to resistance to PTH, PHP1a patients also lack sensitivity for other hormones that signal their actions through G protein-coupled receptors and display physical features of Albright hereditary osteodystrophy (AHO), which is not classically seen in PHP1b patients. PHP1a is caused by heterozygous loss-of-function mutations in maternally inherited GNAS exons 1-13, which encode Gsα. PHP1b is often caused by deletion of the STX16 gene, which is thought to have an important role in controlling the methylation and thus imprinting at part of the GNAS locus. Here we present a patient with PHP1b caused by the previously described recurrent 3-kb STX16 deletion. The patient's first symptoms were macrosomia, early onset obesity, and macrocephaly. Since this is an atypical but previously described rare presentation of PHP1b, we reemphasize STX16 deletions and PHP1b as a rare cause for early onset obesity and macrosomia. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Iris M de Lange
- Department of Medical Genetics, University Medical Centre, Utrecht, The Netherlands
| | | | - Rob B van der Luijt
- Department of Medical Genetics, University Medical Centre, Utrecht, The Netherlands
| | | | - Mieke M van Haelst
- Department of Medical Genetics, University Medical Centre, Utrecht, The Netherlands
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14
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Takatani R, Molinaro A, Grigelioniene G, Tafaj O, Watanabe T, Reyes M, Sharma A, Singhal V, Raymond FL, Linglart A, Jüppner H. Analysis of Multiple Families With Single Individuals Affected by Pseudohypoparathyroidism Type Ib (PHP1B) Reveals Only One Novel Maternally Inherited GNAS Deletion. J Bone Miner Res 2016; 31:796-805. [PMID: 26479409 PMCID: PMC4826817 DOI: 10.1002/jbmr.2731] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Revised: 10/05/2015] [Accepted: 10/12/2015] [Indexed: 01/22/2023]
Abstract
Proximal tubular resistance to parathyroid hormone (PTH) resulting in hypocalcemia and hyperphosphatemia are preeminent abnormalities in pseudohypoparathyroidism type Ib (PHP1B), but resistance toward other hormones as well as variable features of Albright's Hereditary Osteodystrophy (AHO) can occur also. Genomic DNA from PHP1B patients shows epigenetic changes at one or multiple differentially methylated regions (DMRs) within GNAS, the gene encoding Gαs and splice variants thereof. In the autosomal dominant disease variant, these methylation abnormalities are caused by deletions in STX16 or GNAS on the maternal allele. The molecular defect(s) leading to sporadic PHP1B (sporPHP1B) remains in most cases unknown and we therefore analyzed 60 sporPHP1B patients and available family members by microsatellite markers, single nucleotide polymorphisms (SNPs), multiplex ligation-dependent probe amplification (MLPA), and methylation-specific MLPA (MS-MLPA). All investigated cases revealed broad GNAS methylation changes, but no evidence for inheritance of two paternal chromosome 20q alleles. Some patients with partial epigenetic modifications in DNA from peripheral blood cells showed more complete GNAS methylation changes when testing their immortalized lymphoblastoid cells. Analysis of siblings and children of sporPHP1B patients provided no evidence for an abnormal mineral ion regulation and no changes in GNAS methylation. Only one patient revealed, based on MLPA and microsatellite analyses, evidence for an allelic loss, which resulted in the discovery of two adjacent, maternally inherited deletions (37,597 and 1427 bp, respectively) that remove the area between GNAS antisense exons 3 and 5, including exon NESP. Our findings thus emphasize that the region comprising antisense exons 3 and 4 is required for establishing all maternal GNAS methylation imprints. The genetic defect(s) leading in sporPHP1B to epigenetic GNAS changes and thus PTH-resistance remains unknown, but it seems unlikely that this disease variant is caused by heterozygous inherited or de novo mutations involving GNAS.
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Affiliation(s)
- Rieko Takatani
- Endocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Angelo Molinaro
- Endocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Giedre Grigelioniene
- Endocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Olta Tafaj
- Endocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Tomoyuki Watanabe
- Endocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Monica Reyes
- Endocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Amita Sharma
- Pediatric Nephrology Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Vibha Singhal
- Pediatric Endocrinology Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - F Lucy Raymond
- Department of Medical Genetics, Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
| | - Agnès Linglart
- Paediatric Endocrinology and Diabetology, French National Reference Centre for Rare Disorders of Mineral Metabolism, AP-HP Hôpital Bicêtre Paris Sud, le Kremlin-Bicêtre, France
- Faculté de Médecine, Université Paris Sud, le Kremlin-Bicêtre, France
| | - Harald Jüppner
- Endocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
- Pediatric Nephrology Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
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Picard C, Decrequy A, Guenet D, Bursztejn AC, Toledano D, Richard N, Kottler ML. Diagnosis and management of congenital hypothyroidism associated with pseudohypoparathyroidism. Horm Res Paediatr 2015; 83:111-7. [PMID: 25591844 DOI: 10.1159/000369492] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Accepted: 10/29/2014] [Indexed: 11/19/2022] Open
Abstract
UNLABELLED Hypothyroidism is a particular condition observed in pseudohypoparathyroidism (PHP), a rare disorder characterized by parathyroid (PTH) resistance leading to hypocalcemia and hyperphosphatemia associated with a GNAS (guanine nucleotide-binding protein α-subunit) mutation (PHP1A) or epimutation (PHP1B). To determine the presence of hypothyroidism at birth we conducted a retrospective study in our cohort of patients presenting with either PHP1A (n = 116) or PHP1B (n = 99). We also investigated patients presenting at birth with congenital hypothyroidism (CH) and a eutopic thyroid gland for phosphocalcium abnormalities suggesting PTH resistance and PHP. Our study reveals CH as the earliest diagnostic clue for PHP1A, but not for PHP1B. We estimated the frequency of CH at birth to be between 8 and 34% in patients presenting with PHP1A. The elevation of phosphatemia and PTH concentration precedes hypocalcemia in PHP1A. Conversely, the frequency of PHP1A in patients presenting CH is dramatically low. This may be due to the low prevalence of PHP1A which remains unknown. CONCLUSIONS Subclinical and overt hypothyroidism can occur in PHP1A patients at birth many years before PTH resistance becomes clinically apparent. Although such cases appear to be rare, some pediatric patients with unexplained CH are likely to benefit from measuring calcium, phosphorus, and PTH for extended periods of time.
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Affiliation(s)
- Charlotte Picard
- Service de Génétique, Centre de Référence des Maladies Rares du Métabolisme du Calcium et du Phosphore, CHU de Caen, Caen, France
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Abnormal Methylation Status of the GNAS Exon 1A Region in Pseudohypohyperparathyroidism Combined With Turner Syndrome. Am J Med Sci 2015; 350:458-62. [PMID: 26488942 DOI: 10.1097/maj.0000000000000589] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Pseudohypohyperparathyroidism (PHHP) is a rare type of pseudohypoparathyroidism (PHP), which seems to have a normal skeletal response to parathyroid hormone but shows renal resistance. Almost all patients with PHHP have PHP Ib, a subtype of PHP that is usually caused by GNAS methylation defects, often in exon 1A. Some features of Albright hereditary osteodystrophy can occasionally be found in patients with PHHP, but these features are also common in Turner syndrome. The authors report on an extremely rare case of a patient with PHHP and Turner syndrome, a 47-year-old woman who sought medical attention for hypocalcemia and elevated parathyroid hormone. She had no family history of hypocalcemia and no STX16 gene deletions. She had a mosaic karyotype of 46, X, del(X)(p11.4)/45, XO. Pyrosequencing was performed to determine the GNAS exon 1A methylation. The degree of methylation found in exon 1A of the patient was lower than her unaffected relatives.
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Abstract
The GNAS complex locus encodes the alpha-subunit of the stimulatory G protein (Gsα), a ubiquitous signaling protein mediating the actions of many hormones, neurotransmitters, and paracrine/autocrine factors via generation of the second messenger cAMP. GNAS gives rise to other gene products, most of which exhibit exclusively monoallelic expression. In contrast, Gsα is expressed biallelically in most tissues; however, paternal Gsα expression is silenced in a small number of tissues through as-yet-poorly understood mechanisms that involve differential methylation within GNAS. Gsα-coding GNAS mutations that lead to diminished Gsα expression and/or function result in Albright's hereditary osteodystrophy (AHO) with or without hormone resistance, i.e., pseudohypoparathyroidism type-Ia/Ic and pseudo-pseudohypoparathyroidism, respectively. Microdeletions that alter GNAS methylation and, thereby, diminish Gsα expression in tissues in which the paternal Gsα allele is normally silenced also cause hormone resistance, which occurs typically in the absence of AHO, a disorder termed pseudohypoparathyroidism type-Ib. Mutations of GNAS that cause constitutive Gsα signaling are found in patients with McCune-Albright syndrome, fibrous dysplasia of bone, and different endocrine and non-endocrine tumors. Clinical features of these diseases depend significantly on the parental allelic origin of the GNAS mutation, reflecting the tissue-specific paternal Gsα silencing. In this article, we review the pathogenesis and the phenotypes of these human diseases.
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Affiliation(s)
- Serap Turan
- Pediatric Endocrinology, Marmara University School of Medicine Hospital, Istanbul, Turkey;
| | - Murat Bastepe
- Endocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114;
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Cao GL, Feng T, Chu MX, Di R, Zhang YL, Huang DW, Liu QY, Hu WP, Wang XY. Subtraction suppressive hybridisation analysis of differentially expressed genes associated with puberty in the goat hypothalamus. Reprod Fertil Dev 2015; 28:RD14434. [PMID: 25976271 DOI: 10.1071/rd14434] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Accepted: 04/13/2015] [Indexed: 01/19/2023] Open
Abstract
The cost of developing replacement nanny goats could be reduced by decreasing the age at puberty because this way nanny goats could be brought into production at an earlier age. The aim of the present study was to screen genes related to puberty to investigate the molecular mechanisms of puberty. Subtracted cDNA libraries were constructed for hypothalami from juvenile (Group A), pubertal (Group B) and age-matched control pubertal (Group E) Jining grey (JG) and Liaoning cashmere (LC) goats using suppression subtractive hybridisation (SSH). Differentially expressed genes were analysed by bioinformatics methods. There were 203 expressed sequence tags (ESTs) in the subtracted cDNA libraries that were differentially expressed between JG and LC goats at the juvenile stage, 226 that were differentially expressed at puberty and 183 that were differentially expressed in the age-matched control group. The differentially expressed ESTs in each subtracted cDNA library were classified as known gene, known EST and unknown EST according to sequence homology in the GenBank non-redundant (NR) and EST database. According to gene function analysis in the COG (Cluster of Orthologous Groups) database, the known genes were grouped into 10 subdivisions in Group A, into seven subdivisions in Group E and into nine subdivisions in Group B under three categories: cellular processes and signalling, information storage and processing, and metabolism. Pathway analysis in the KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway database of known genes revealed that the three pathways that most differentially expressed genes were involved in were metabolic pathways, Parkinson's disease and oxidative phosphorylation. Protein interaction analysis of the high homology genes revealed the most dominant network to be structure of ribosome/protein translation, oxidative phosphorylation and carbohydrate metabolism. The results reveal that the onset of puberty is a complex event involving multiple genes in multiple biological processes. The differentially expressed genes include genes related to both neuroendocrine and energy metabolism.
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Mantovani G, Elli FM. Pseudohypoparathyroidism type Ib in 2015. ANNALES D'ENDOCRINOLOGIE 2015; 76:101-4. [PMID: 25910998 DOI: 10.1016/j.ando.2015.03.028] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Accepted: 03/11/2015] [Indexed: 10/23/2022]
Abstract
The term pseudohypoparathryoidism (PHP) refers to a group of rare genetic and epigenetic disorders characterized by resistance to the action of parathyroid hormone (PTH) that activates cAMP signaling in target cells. Together with pseudohypoparathyroidism, Albright hereditary osteodystrophy (AHO) and progressive osseous heteroplasia (POH) represent rare, related and deeply impairing disorders encompassing heterogeneous features, such as brachydactyly, ectopic ossifications, short stature, mental retardation and endocrine deficiencies due to resistance to the action of different hormones. The two main subtypes, PHP-Ia and PHP-Ib, are caused by mutations in GNAS exons 1-13 and methylation defects in the imprinted GNAS cluster respectively, while mutations in the PRKAR1A and PDE4D genes (also involved in mediating cAMP signalling) have been demonstrated in patients with acrodysostosis, a disease of bone formation with characteristics similar to AHO. The molecular overlap among these disorders indicates the need for different classification models and seriously alters our understanding of the mechanisms through which GNAS defects, together with the new recently described defects involving other components of the cAMP signalling cascade, cause AHO-related disorders.
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Affiliation(s)
- Giovanna Mantovani
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Endocrinology and Diabetology Unit, Department of Clinical Sciences and Community Health, University of Milan, Via F. Sforza, 35, 20122 Milan, Italy.
| | - Francesca M Elli
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Endocrinology and Diabetology Unit, Department of Clinical Sciences and Community Health, University of Milan, Via F. Sforza, 35, 20122 Milan, Italy
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20
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Molinaro A, Tiosano D, Takatani R, Chrysis D, Russell W, Koscielniak N, Kottler ML, Agretti P, De Marco G, Ahtiainen P, Christov M, Mäkitie O, Tonacchera M, Jüppner H. TSH elevations as the first laboratory evidence for pseudohypoparathyroidism type Ib (PHP-Ib). J Bone Miner Res 2015; 30:906-12. [PMID: 25403028 PMCID: PMC4401615 DOI: 10.1002/jbmr.2408] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Revised: 11/05/2014] [Accepted: 11/10/2014] [Indexed: 01/21/2023]
Abstract
Hypocalcemia and hyperphosphatemia because of resistance toward parathyroid hormone (PTH) in the proximal renal tubules are the most prominent abnormalities in patients affected by pseudohypoparathyroidism type Ib (PHP-Ib). In this rare disorder, which is caused by GNAS methylation changes, resistance can occur toward other hormones, such as thyroid-stimulating hormone (TSH), that mediate their actions through G protein-coupled receptors. However, these additional laboratory abnormalities are usually not recognized until PTH-resistant hypocalcemia becomes clinically apparent. We now describe four pediatric patients, first diagnosed with subclinical or overt hypothyroidism between the ages of 0.2 and 15 years, who developed overt PTH-resistance 3 to 20 years later. Although anti-thyroperoxidase (anti-TPO) antibodies provided a plausible explanation for hypothyroidism in one of these patients, this and two other patients revealed broad epigenetic GNAS abnormalities, which included loss of methylation (LOM) at exons AS, XL, and A/B, and gain of methylation at exon NESP55; ie, findings consistent with PHP-Ib. LOM at GNAS exon A/B alone led in the fourth patient to the identification of a maternally inherited 3-kb STX16 deletion, a well-established cause of autosomal dominant PHP-Ib. Although GNAS methylation changes were not detected in additional pediatric and adult patients with subclinical hypothyroidism (23 pediatric and 39 adult cases), hypothyroidism can obviously be the initial finding in PHP-Ib patients. One should therefore consider measuring PTH, along with calcium and phosphate, in patients with unexplained hypothyroidism for extended periods of time to avoid hypocalcemia and associated clinical complications.
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Affiliation(s)
- Angelo Molinaro
- Endocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
- Endocrinology Unit, Department of Clinical and Experimental Medicine, University of Pisa, University Hospital of Pisa, Pisa, Italy
| | - Dov Tiosano
- Division of Pediatric Endocrinology, Meyer Children's Hospital, Rambam Health Care Campus, Haifa, Israel
| | - Rieko Takatani
- Endocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Dionisios Chrysis
- Department of Pediatrics, Medical School, University of Patras, Patras, Greece
| | - William Russell
- Division of Pediatric Endocrinology and Diabetes, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Nikolas Koscielniak
- Program in Occupational Therapy, Washington University School of Medicine, St. Louis, MO, USA
| | - Marie-Laure Kottler
- Centre Hospitalier Universitaire de Caen, Department of Genetics, Reference Centre for Rare Disorders of Calcium and Phosphorus Metabolism, F-14000 Caen, France
| | - Patrizia Agretti
- Endocrinology Unit, Department of Clinical and Experimental Medicine, University of Pisa, University Hospital of Pisa, Pisa, Italy
| | - Giuseppina De Marco
- Endocrinology Unit, Department of Clinical and Experimental Medicine, University of Pisa, University Hospital of Pisa, Pisa, Italy
| | - Petteri Ahtiainen
- Central Finland Central Hospital, Jyväskylä, and Kuopio University Hospital, Kuopio, Finland
| | - Marta Christov
- Endocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Outi Mäkitie
- Hospital for Children and Adolescents, University of Helsinki, and Folkhälsan Institute of Genetics, Helsinki, Finland
| | - Massimo Tonacchera
- Endocrinology Unit, Department of Clinical and Experimental Medicine, University of Pisa, University Hospital of Pisa, Pisa, Italy
| | - Harald Jüppner
- Endocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
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21
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Bréhin AC, Colson C, Maupetit-Méhouas S, Grybek V, Richard N, Linglart A, Kottler ML, Jüppner H. Loss of methylation at GNAS exon A/B is associated with increased intrauterine growth. J Clin Endocrinol Metab 2015; 100:E623-31. [PMID: 25603460 PMCID: PMC4399294 DOI: 10.1210/jc.2014-4047] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Accepted: 01/14/2015] [Indexed: 01/26/2023]
Abstract
CONTEXT GNAS is one of few genetic loci that undergo allelic-specific methylation resulting in the parent-specific expression of at least four different transcripts. Due to monoallelic expression, heterozygous GNAS mutations affecting either paternally or maternally derived transcripts cause different forms of pseudohypoparathyroidism (PHP), including autosomal-dominant PHP type Ib (AD-PHP1B) associated with loss of methylation (LOM) at exon A/B alone or sporadic PHP1B (sporPHP1B) associated with broad GNAS methylation changes. Similar to effects other imprinted genes have on early development, we recently observed severe intrauterine growth retardation in newborns, later diagnosed with pseudopseudohypoparathyroidism (PPHP) because of paternal GNAS loss-of-function mutations. OBJECTIVES This study aimed to determine whether GNAS methylation abnormalities affect intrauterine growth. PATIENTS AND METHODS Birth parameters were collected of patients who later developed sporPHP1B or AD-PHP1B, and of their healthy siblings. Comparisons were made to newborns affected by PPHP or PHP1A. RESULTS As newborns, AD-PHP1B patients were bigger than their healthy siblings and well above the reference average; increased sizes were particularly evident if the mothers were unaffected carriers of STX16 deletions. SporPHP1B newborns were slightly above average for weight and length, but their overgrowth was less pronounced than that of AD-PHP1B newborns from unaffected mothers. CONCLUSION LOM at GNAS exon A/B due to maternal STX16 deletions and the resulting biallelic A/B expression are associated with enhanced fetal growth. These findings are distinctly different from those of PPHP patients with paternal GNAS exons 2-13 mutations, whose birth parameters are almost 4.5 z-scores below those of AD-PHP1B patients born to healthy mothers.
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Affiliation(s)
- Anne-Claire Bréhin
- Department of Genetics (A.-C.B., C.C., N.R., M.-L.K.), Centre Hospitalier Universitaire de Caen, Reference Centre for Rare Disorders of Calcium and Phosphorus Metabolism, F-14000 Caen, France; Paediatric Endocrinology and Diabetology (S.M.-M., V.G., A.L.), Reference Centre for Rare Disorders of the Mineral Metabolism, AP-HP Hôpital Bicêtre, le Kremlin-Bicêtre 94270, France; Faculté de Médecine, Université Paris Sud, le Kremlin-Bicêtre 94270, France; and Pediatric Nephrology Unit and Endocrine Unit (H.J.), Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114
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22
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Romanet P, Osei L, Netchine I, Pertuit M, Enjalbert A, Reynaud R, Barlier A. Case report of GNAS epigenetic defect revealed by a congenital hypothyroidism. Pediatrics 2015; 135:e1079-83. [PMID: 25802348 DOI: 10.1542/peds.2014-2806] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Pseudohypoparathyroidism (PHP) is a group of disorders characterized by end-organ resistance to the parathyroid hormone (PTH). PHP type 1A includes multihormone resistance syndrome, Albright's hereditary osteodystrophy, and obesity and is caused by mutations in GNAS exon 1 through 13. PHP type 1B (PHP1B), caused by epigenetic changes in the GNAS locus, was initially described as an isolated resistance to PTH. Epigenetic changes in GNAS have also been reported in patients who display mild Albright's hereditary osteodystrophy or mild thyroid-stimulating hormone (TSH) resistance without mutation of GNAS. Here we report a case of PHP caused by epigenetic changes in GNAS in a patient with congenital hypothyroidism. The patient was referred for a positive newborn screening for hypothyroidism (TSH 50 mIU/L). She exhibited severe clinical features of congenital hypothyroidism. The thyroid was in place, and etiologic explorations were negative. TSH was normalized under L-thyroxin, and the symptoms disappeared, except for a macroglossia. In childhood, PHP was suspected in addition to elevated PTH, obesity, brachydactyly, and a rounded face. Sequencing, methylation analysis, and large deletion research were performed in GNAS. No genetic mutations were found. Methylation analysis revealed a broad epigenetic defect without deletion in GNAS consistent with sporadic PHP1B. The multilocus methylation analysis were negative. This finding expands the known onsets of PHP1B and emphasizes the need for a new PHP classification system. This case report has important consequences for the etiologic diagnosis of congenital hypothyroidism because it adds a new cause of the disease.
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Affiliation(s)
- Pauline Romanet
- Assistance Publique Hôpitaux de Marseille, Hôpital la Conception, Laboratory of Molecular Biology, Marseille, France; Aix Marseille Université, CNRS, CRN2M-UMR 7286, Marseille, France
| | - Lindsay Osei
- Assistance Publique Hôpitaux de Marseille, Hôpital La Timone Enfant, Departments of Pediatrics, Marseille, France
| | - Irène Netchine
- Institut National de la Santé et de la Recherche Médicale, Centre de Recherche Saint-Antoine, UMR_S 938, Paris, France; and Sorbonne Universités, Paris, France
| | - Morgane Pertuit
- Assistance Publique Hôpitaux de Marseille, Hôpital la Conception, Laboratory of Molecular Biology, Marseille, France
| | - Alain Enjalbert
- Assistance Publique Hôpitaux de Marseille, Hôpital la Conception, Laboratory of Molecular Biology, Marseille, France; Aix Marseille Université, CNRS, CRN2M-UMR 7286, Marseille, France
| | - Rachel Reynaud
- Aix Marseille Université, CNRS, CRN2M-UMR 7286, Marseille, France; Assistance Publique Hôpitaux de Marseille, Hôpital La Timone Enfant, Departments of Pediatrics, Marseille, France
| | - Anne Barlier
- Assistance Publique Hôpitaux de Marseille, Hôpital la Conception, Laboratory of Molecular Biology, Marseille, France; Aix Marseille Université, CNRS, CRN2M-UMR 7286, Marseille, France;
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Inta IM, Choukair D, Bender S, Kneppo C, Knauer-Fischer S, Meyenburg K, Ivandic B, Pfister SM, Bettendorf M. Guanine nucleotide-binding protein α subunit hypofunction in children with short stature and disproportionate shortening of the 4th and 5th metacarpals. Horm Res Paediatr 2014; 81:196-203. [PMID: 24481334 DOI: 10.1159/000356928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Accepted: 10/28/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND GNAS encodes the α subunit of the stimulatory G protein (Gsα). Maternal inherited Gsα mutations cause pseudohypoparathyroidism type Ia (PHP-Ia), associated with shortening of the 4th and 5th metacarpals. AIMS Here we investigated the Gsα pathway in short patients with distinct shortening of the 4th and 5th metacarpals. METHODS In 571 children with short stature and 4 patients with PHP-Ia metacarpal bone lengths were measured. In identified patients we analysed the Gsα protein function in platelets, performed GNAS sequencing, and epigenetic analysis of four significant differentially methylated regions. RESULTS In 51 patients (8.9%) shortening of the 4th and 5th metacarpals was more pronounced than their height deficit. No GNAS coding mutations were identified in 20 analysed patients, except in 2 PHP-Ia patients. Gsα activity was reduced in all PHP-Ia patients and in 25% of the analysed patients. No significant methylation changes were identified. CONCLUSIONS Our findings suggest that patients with short stature and distinct metacarpal bone shortening could be part of the wide variety of PHP/PPHP, therefore it was worthwhile analysing the Gsα protein function and GNAS gene in these patients in order to further elucidate the phenotype and genotype of Gsα dysfunction.
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Affiliation(s)
- Ioana Monica Inta
- Division of Paediatric Endocrinology, University Children's Hospital Heidelberg, Heidelberg, Germany
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24
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European guidance for the molecular diagnosis of pseudohypoparathyroidism not caused by point genetic variants at GNAS: an EQA study. Eur J Hum Genet 2014; 23:438-44. [PMID: 25005735 DOI: 10.1038/ejhg.2014.127] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Revised: 05/20/2014] [Accepted: 05/30/2014] [Indexed: 12/19/2022] Open
Abstract
Pseudohypoparathyroidism is a rare endocrine disorder that can be caused by genetic (mainly maternally inherited inactivating point mutations, although intragenic and gross deletions have rarely been reported) or epigenetic alterations at GNAS locus. Clinical and molecular characterization of this disease is not that easy because of phenotypic, biochemical and molecular overlapping features between both subtypes of the disease. The European Consortium for the study of PHP (EuroPHP) designed the present work with the intention of generating the standards of diagnostic clinical molecular (epi)genetic testing in PHP patients. With this aim, DNA samples of eight independent PHP patients carrying GNAS genetic and/or epigenetic defects (three patients with GNAS deletions, two with 20q uniparental disomy and three with a methylation defect of unknown origin) without GNAS point mutations were anonymized and sent to the five participant laboratories for their routine genetic analysis (methylation-specific (MS)-MLPA, pyrosequencing and EpiTYPER) and interpretations. All laboratories were able to detect methylation defects and, after the data analysis, the Consortium compared the results to define technical advantages and disadvantages of different techniques. To conclude, we propose as first-level investigation in PHP patients copy number and methylation analysis by MS-MLPA. Then, in patients with partial methylation defect, the result should be confirmed by single CpG bisulphite-based methods (ie pyrosequencing), whereas in case of a complete methylation defect without detectable deletion, microsatellites or SNP genotyping should be performed to exclude uniparental disomy 20.
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25
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Das R, Lee YK, Strogantsev R, Jin S, Lim YC, Ng PY, Lin XM, Chng K, Yeo GSH, Ferguson-Smith AC, Ding C. DNMT1 and AIM1 Imprinting in human placenta revealed through a genome-wide screen for allele-specific DNA methylation. BMC Genomics 2013; 14:685. [PMID: 24094292 PMCID: PMC3829101 DOI: 10.1186/1471-2164-14-685] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Accepted: 09/25/2013] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Genomic imprinting is an epigenetically regulated process wherein genes are expressed in a parent-of-origin specific manner. Many imprinted genes were initially identified in mice; some of these were subsequently shown not to be imprinted in humans. Such discrepancy reflects developmental, morphological and physiological differences between mouse and human tissues. This is particularly relevant for the placenta. Study of genomic imprinting thus needs to be carried out in a species and developmental stage-specific manner. We describe here a new strategy to study allele-specific DNA methylation in the human placenta for the discovery of novel imprinted genes. RESULTS Using this methodology, we confirmed 16 differentially methylated regions (DMRs) associated with known imprinted genes. We chose 28 genomic regions for further testing and identified two imprinted genes (DNMT1 and AIM1). Both genes showed maternal allele-specific methylation and paternal allele-specific transcription. Imprinted expression for AIM1 was conserved in the cynomolgus macaque placenta, but not in other macaque tissues or in the mouse. CONCLUSIONS Our study indicates that while there are many genomic regions with allele-specific methylation in tissues like the placenta, only a small sub-set of them are associated with allele-specific transcription, suggesting alternative functions for such genomic regions. Nonetheless, novel tissue-specific imprinted genes remain to be discovered in humans. Their identification may help us better understand embryonic and fetal development.
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Affiliation(s)
- Radhika Das
- Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Yew Kok Lee
- Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Ruslan Strogantsev
- Department of Physiology, Development & Neuroscience, University of Cambridge, Cambridge, UK
| | - Shengnan Jin
- Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Yen Ching Lim
- Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Poh Yong Ng
- Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Xueqin Michelle Lin
- Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Keefe Chng
- Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - George SH Yeo
- Department of Maternal Fetal Medicine, K.K. Women’s and Children’s Hospital, Singapore, Singapore
| | - Anne C Ferguson-Smith
- Department of Physiology, Development & Neuroscience, University of Cambridge, Cambridge, UK
| | - Chunming Ding
- Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
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Menigatti M, Staiano T, Manser CN, Bauerfeind P, Komljenovic A, Robinson M, Jiricny J, Buffoli F, Marra G. Epigenetic silencing of monoallelically methylated miRNA loci in precancerous colorectal lesions. Oncogenesis 2013; 2:e56. [PMID: 23857251 PMCID: PMC3740287 DOI: 10.1038/oncsis.2013.21] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Revised: 05/10/2013] [Accepted: 05/15/2013] [Indexed: 12/15/2022] Open
Abstract
Epigenetic silencing of protein-encoding genes is common in early-stage colorectal tumorigenesis. Less is known about the methylation-mediated silencing of genes encoding microRNAs (miRNAs), which are also important epigenetic modulators of gene expression. Using quantitative PCR, we identified 56 miRNAs that were expressed in normal colorectal mucosa and in HT29 colorectal cancer cells treated with demethylating agents but not in untreated HT29 cells, suggesting that they probably undergo methylation-induced silencing during colorectal tumorigenesis. One of these, miR-195, had recently been reported to be underexpressed in colorectal cancers and to exert tumor-suppressor effects in colorectal cancer cells. We identified the transcription start site (TSS) for primary miRNA (pri-miR)-497/195, the primary precursor that yields miR-195 and another candidate on our list, miR-497, and a single CpG island upstream to the TSS, which controls expression of both miRNAs. Combined bisulfite restriction analysis and bisulfite genomic sequencing studies revealed monoallelic methylation of this island in normal colorectal mucosa (50/50 samples) and full methylation in most colorectal adenomas (38/50; 76%). The hypermethylated precancerous lesions displayed significantly downregulated expression of both miRNAs. Similar methylation patterns were observed at two known imprinted genes, MEG3 and GNAS-AS1, which encode several of the 56 miRNAs on our list. Imprinting at these loci was lost in over half the adenomas (62% at MEG3 and 52% at GNAS-AS1). Copy-number alterations at MEG3, GNAS-AS1 and pri-miR-497/195, which are frequent in colorectal cancers, were less common in adenomas and confined to tumors displaying differential methylation at the involved locus. Our data show that somatically acquired, epigenetic changes at monoallelically methylated regions encoding miRNAs are relatively frequent in sporadic colorectal adenomas and might contribute to the onset and progression of these tumors.
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Affiliation(s)
- M Menigatti
- Institute of Molecular Cancer Research, University of Zurich, Zurich, Switzerland
| | - T Staiano
- Gastroenterology and Endoscopy Unit, Hospital of Cremona, Cremona, Italy
| | - C N Manser
- Gastroenterology and Endoscopy Unit, University of Zurich Hospital, Zurich, Switzerland
| | - P Bauerfeind
- Gastroenterology and Endoscopy Unit, University of Zurich Hospital, Zurich, Switzerland
| | - A Komljenovic
- Institute of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - M Robinson
- Institute of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - J Jiricny
- Institute of Molecular Cancer Research, University of Zurich, Zurich, Switzerland
| | - F Buffoli
- Gastroenterology and Endoscopy Unit, Hospital of Cremona, Cremona, Italy
| | - G Marra
- Institute of Molecular Cancer Research, University of Zurich, Zurich, Switzerland
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Yuno A, Usui T, Yambe Y, Higashi K, Ugi S, Shinoda J, Mashio Y, Shimatsu A. Genetic and epigenetic states of the GNAS complex in pseudohypoparathyroidism type Ib using methylation-specific multiplex ligation-dependent probe amplification assay. Eur J Endocrinol 2013; 168:169-75. [PMID: 23132697 DOI: 10.1530/eje-12-0548] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
CONTEXT Pseudohypoparathyroidism type Ib (PHP-Ib) is a rare disorder resulting from genetic and epigenetic aberrations in the GNAS complex. PHP-Ib, usually defined by renal resistance to parathyroid hormone, is due to a maternal loss of GNAS exon A/B methylation and leads to decreased expression of the stimulatory G protein α (Gsα) in specific tissues. OBJECTIVE To clarify the usefulness of methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA), we evaluated genetic and epigenetic changes of the GNAS locus in Japanese PHP-Ib patients. DESIGN Retrospective case series. PATIENTS We studied 13 subjects with PHP-Ib (three families with eight affected members and one unaffected member and four sporadic cases). MEASUREMENTS The methylation status of GNAS differentially methylated regions (DMRs) was evaluated using MS-MLPA. The main outcome measure was the presence of deletion mutations in the GNAS locus and STX16, which were assessed using MLPA. RESULTS In all familial PHP-Ib cases, a ~3 kb deletion of STX16 and demethylation of the A/B domain were identified. In contrast, no deletion was detected throughout the entire GNAS locus region in the sporadic cases. Broad methylation abnormalities were observed in the GNAS DMRs. CONCLUSIONS MS-MLPA allows for precise and rapid analysis of the methylation status in GNAS DMRs as well as the detection of microdeletion mutations in PHP-Ib. Results confirm the previous findings in this disorder and demonstrate that this method is valuable for the genetic evaluation and visualizing the methylation status. The MS-MLPA assay is a useful tool that may facilitate making the molecular diagnosis of PHP-Ib.
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Affiliation(s)
- Akiko Yuno
- Clinical Research Institute, National Hospital Organization Kyoto Medical Center, 1-1 Mukaihata-cho, Fukakusa, Fushimi-ku, Kyoto 612-8555, Japan
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Almeida Campos T, Moura C, Castro-Correia C, Fontoura M. Seudohipoparatiroidismo tipo 1b: una causa rara de síncope. An Pediatr (Barc) 2013; 78:131-3. [DOI: 10.1016/j.anpedi.2012.06.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Revised: 06/18/2012] [Accepted: 06/27/2012] [Indexed: 10/28/2022] Open
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Chong PL, Meeking DR. Pseudohypoparathyroidism: a rare but important cause of hypocalcaemia. BMJ Case Rep 2013; 2013:bcr-2012-008040. [PMID: 23345494 DOI: 10.1136/bcr-2012-008040] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
We present a 46-year-old Caucasian lady with symptomatic hypocalcaemia. Investigations revealed markedly raised parathyroid hormone (PTH) levels with vitamin D deficiency. A number of conditions causing secondary hyperparathyroidism were ruled out from her medical history and initial investigations. The main differential diagnoses were vitamin D deficiency and PTH resistance (pseudohypoparathyroidism, PHP). With high-normal serum phosphate and normal alkaline phosphatase, and a lack of symptoms associated with osteomalacia, vitamin D deficiency alone was unlikely to be the cause of hypocalcaemia. Given a normal physical appearance, genetic testing was arranged and confirmed the diagnosis of PHP type Ib. She is currently taking activated vitamin D to maintain calcium homeostasis. PTH resistance is the hallmark of PHP, a rare complex genetic disorder, which can be easily missed resulting in potentially serious consequences.
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Affiliation(s)
- Pui Lin Chong
- Academic Department of Diabetes and Endocrinology, Portsmouth Hospitals NHS Trust, Portsmouth, UK.
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Turan S, Bastepe M. The GNAS complex locus and human diseases associated with loss-of-function mutations or epimutations within this imprinted gene. Horm Res Paediatr 2013; 80:229-41. [PMID: 24107509 PMCID: PMC3874326 DOI: 10.1159/000355384] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Accepted: 08/29/2013] [Indexed: 12/14/2022] Open
Abstract
GNAS is a complex imprinted locus leading to several different gene products that show exclusive monoallelic expression. GNAS also encodes the α-subunit of the stimulatory G protein (Gsα), a ubiquitously expressed signaling protein that is essential for the actions of many hormones and other endogenous molecules. Gsα is expressed biallelically in most tissues but its expression is silenced from the paternal allele in a small number of tissues. The tissue-specific paternal silencing of Gsα results in different parent-of-origin-specific phenotypes in patients who carry inactivating GNAS mutations. In this paper, we review the GNAS complex locus and discuss how disruption of Gsα expression and the expression of other GNAS products shape the phenotypes of human disorders caused by mutations in this gene.
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Affiliation(s)
- Serap Turan
- Pediatric Endocrinology, Marmara University School of Medicine Hospital, Istanbul, Turkey
| | - Murat Bastepe
- Endocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA
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Frequency and characterization of DNA methylation defects in children born SGA. Eur J Hum Genet 2012; 21:838-43. [PMID: 23232699 DOI: 10.1038/ejhg.2012.262] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2012] [Revised: 10/16/2012] [Accepted: 11/01/2012] [Indexed: 11/08/2022] Open
Abstract
Various genes located at imprinted loci and regulated by epigenetic mechanisms are involved in the control of growth and differentiation. The broad phenotypic variability of imprinting disorders suggests that individuals with inborn errors of imprinting might remain undetected among patients born small for gestational age (SGA). We evaluated quantitative DNA methylation analysis at differentially methylated regions (DMRs) of 10 imprinted loci (PLAGL1, IGF2R DMR2, GRB10, H19 DMR, IGF2, MEG3, NDN, SNRPN, NESP, NESPAS) by bisulphite pyrosequencing in 98 patients born SGA and 50 controls. For IGF2R DMR2, methylation patterns of additional 47 parent pairs and one mother (95 individuals) of patients included in the SGA cohort were analyzed. In six out of 98 patients born SGA, we detected DNA methylation changes at single loci. In one child, the diagnosis of upd(14)mat syndrome owing to an epimutation of the MEG3 locus in 14q32 could be established. The remaining five patients showed hypomethylation at GRB10 (n=2), hypomethylation at the H19 3CTCF-binding site (n=1), hypermethylation at NDN (n=1) and hypermethylation at IGF2 (n=1). IGF2R DMR2 hypermethylation was detected in five patients, six parents of patients in the SGA cohort and two controls. We conclude that aberrant methylation at imprinted loci in children born SGA exists but seems to be rare if known imprinting syndromes are excluded. Further investigations on the physiological variations and the functional consequences of the detected aberrant methylation are necessary before final conclusions on the clinical impact can be drawn.
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Turan S, Ignatius J, Moilanen JS, Kuismin O, Stewart H, Mann NP, Linglart A, Bastepe M, Jüppner H. De novo STX16 deletions: an infrequent cause of pseudohypoparathyroidism type Ib that should be excluded in sporadic cases. J Clin Endocrinol Metab 2012; 97:E2314-9. [PMID: 23087324 PMCID: PMC3513531 DOI: 10.1210/jc.2012-2920] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2012] [Accepted: 09/24/2012] [Indexed: 01/18/2023]
Abstract
CONTEXT Maternally inherited 3-kb STX16 deletions cause autosomal dominant pseudohypoparathyroidism type Ib (PHP-Ib) characterized by PTH resistance with loss of methylation restricted to the GNAS exon A/B. OBJECTIVE The objective of the study was to search for the 3-kb STX16 deletion and to establish haplotypes for the GNAS region for two PHP-Ib patients and their families. SETTING The study was conducted at a research laboratory and tertiary care hospitals. PATIENTS The index cases presented at the ages 8 and 9.5 yr, respectively, with hypocalcemia, hyperphosphatemia, and elevated PTH. INTERVENTIONS There were no interventions. RESULTS DNA analyses of the index cases revealed an isolated loss of the GNAS exon A/B methylation and the 3-kb STX16 deletion. In the first family, the patient's healthy mother and sister showed no genetic or epigenetic abnormality, yet microsatellite analysis of the GNAS region indicated that both siblings share the same maternal allele, with the exception of an allelic loss for marker 261P9-CA1 (located within STX16), leading to the conclusion that a de novo mutation had occurred on the maternal allele. In the second family, three siblings of the index case are also affected, and an analysis of their DNA revealed the 3-kb STX16 deletion, which was also found in the healthy mother and a maternal uncle. Analysis of the siblings of the deceased maternal grandfather and some of their descendants excluded the 3-kb STX16 deletion, but haplotype analysis of the GNAS region suggested that he had acquired the mutation de novo. CONCLUSIONS De novo 3-kb STX16 deletions, reported only once previously, are infrequent but should be excluded in all cases of PHP-Ib, even when the family history is negative for an inherited form of this disorder.
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Affiliation(s)
- Serap Turan
- Endocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114, USA
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Plagge A. Non-Coding RNAs at the Gnas and Snrpn-Ube3a Imprinted Gene Loci and Their Involvement in Hereditary Disorders. Front Genet 2012; 3:264. [PMID: 23226156 PMCID: PMC3509947 DOI: 10.3389/fgene.2012.00264] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Accepted: 11/05/2012] [Indexed: 12/02/2022] Open
Abstract
Non-coding RNAs (ncRNAs) have long been recognized at imprinted gene loci and provided early paradigms to investigate their functions and molecular mechanisms of action. The characteristic feature of imprinted genes, their monoallelic, parental-origin-dependent expression, is achieved through complex epigenetic regulation, which is modulated by ncRNAs. This minireview focuses on two imprinted gene clusters, in which changes in ncRNA expression contribute to human disorders. At the GNAS locus loss of NESP RNA can cause autosomal dominant Pseudohypoparathyroidism type 1b (AD-PHP-Ib), while at the SNRPN-UBE3A locus a long ncRNA and processed snoRNAs play a role in Angelman-Syndrome (AS) and Prader–Willi-Syndrome (PWS). The ncRNAs silence overlapping protein-coding transcripts in sense or anti-sense orientation through changes in histone modifications as well as DNA methylation at CpG-rich sequence motifs. Their epigenetic modulatory functions are required in early development in the pre-implantation embryo or already in the parental germ cells. However, it remains unclear whether the sequence homology-carrying ncRNA itself is required, or whether the process of its transcription through other promoters causes the silencing effect.
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Affiliation(s)
- Antonius Plagge
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool Liverpool, UK
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34
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Neary NM, El-Maouche D, Hopkins R, Libutti SK, Moses AM, Weinstein LS. Development and treatment of tertiary hyperparathyroidism in patients with pseudohypoparathyroidism type 1B. J Clin Endocrinol Metab 2012; 97:3025-30. [PMID: 22736772 PMCID: PMC3431579 DOI: 10.1210/jc.2012-1655] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Accepted: 06/05/2012] [Indexed: 11/19/2022]
Abstract
CONTEXT Pseudohypoparathyroidism type 1B (PHP1B) patients have PTH resistance at the renal proximal tubule and develop hypocalcemia and secondary hyperparathyroidism. Hyperparathyroid bone disease also develops in some patients. PHP1B patients are at theoretical risk of developing tertiary hyperparathyroidism. SETTING Patients were studied in a clinical research center. PATIENTS Five female PHP1B patients presented with hypercalcemia and elevated PTH. INTERVENTION Patients either underwent parathyroidectomy (n = 4) or received cinacalcet (n = 1). MAIN OUTCOME MEASURES Serum calcium and PTH were serially measured before and after intervention. RESULTS Five PHP1B patients developed concomitantly elevated serum calcium and PTH levels (range, 235-864 ng/liter) requiring termination of calcium and vitamin D therapy (time after diagnosis, 21-42 yr; median, 34 yr), consistent with tertiary hyperparathyroidism. Four patients underwent parathyroidectomy with removal of one (n = 2) or two (n = 2) enlarged parathyroid glands. Calcium and vitamin D therapy was reinstituted postoperatively, and at 93-month median follow-up, PTH levels ranged between 56 and 182 (normal, <87) ng/liter. One patient was treated with cinacalcet, resulting in resolution of hypercalcemia. CONCLUSIONS PHP1B patients are at risk of developing tertiary hyperparathyroidism and/or hyperparathyroid bone disease and should therefore be treated with sufficient doses of calcium and vitamin D to achieve serum calcium and PTH levels within or as close to the normal range as possible. Surgery is the treatment of choice in this setting. Cinacalcet may be a useful alternative in those who do not undergo surgery.
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Affiliation(s)
- Nicola M Neary
- Metabolic Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-1752, USA
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Ishida M, Moore GE. The role of imprinted genes in humans. Mol Aspects Med 2012; 34:826-40. [PMID: 22771538 DOI: 10.1016/j.mam.2012.06.009] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2012] [Accepted: 06/27/2012] [Indexed: 10/28/2022]
Abstract
Genomic imprinting, a process of epigenetic modification which allows the gene to be expressed in a parent-of-origin specific manner, has an essential role in normal growth and development. Imprinting is found predominantly in placental mammals, and has potentially evolved as a mechanism to balance parental resource allocation to the offspring. Therefore, genetic and epigenetic disruptions which alter the specific dosage of imprinted genes can lead to various developmental abnormalities often associated with fetal growth and neurological behaviour. Over the past 20 years since the first imprinted gene was discovered, many different mechanisms have been implicated in this special regulatory mode of gene expression. This review includes a brief summary of the current understanding of the key molecular events taking place during imprint establishment and maintenance in early embryos, and their relationship to epigenetic disruptions seen in imprinting disorders. Genetic and epigenetic causes of eight recognised imprinting disorders including Silver-Russell syndrome (SRS) and Beckwith-Wiedemann syndrome (BWS), and also their association with Assisted reproductive technology (ART) will be discussed. Finally, the role of imprinted genes in fetal growth will be explored by investigating their relationship to a common growth disorder, intrauterine growth restriction (IUGR) and also their potential role in regulating normal growth variation.
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Affiliation(s)
- Miho Ishida
- Clinical and Molecular Genetics Unit, Institute of Child Health, University College London, London WC1N 1EH, UK.
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Izzi B, Francois I, Labarque V, Thys C, Wittevrongel C, Devriendt K, Legius E, Van den Bruel A, D'Hooghe M, Lambrechts D, de Zegher F, Van Geet C, Freson K. Methylation defect in imprinted genes detected in patients with an Albright's hereditary osteodystrophy like phenotype and platelet Gs hypofunction. PLoS One 2012; 7:e38579. [PMID: 22679513 PMCID: PMC3367970 DOI: 10.1371/journal.pone.0038579] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2011] [Accepted: 05/07/2012] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Pseudohypoparathyroidism (PHP) indicates a group of heterogeneous disorders whose common feature is represented by impaired signaling of hormones that activate Gsalpha, encoded by the imprinted GNAS gene. PHP-Ib patients have isolated Parathormone (PTH) resistance and GNAS epigenetic defects while PHP-Ia cases present with hormone resistance and characteristic features jointly termed as Albright's Hereditary Osteodystrophy (AHO) due to maternally inherited GNAS mutations or similar epigenetic defects as found for PHP-Ib. Pseudopseudohypoparathyroidism (PPHP) patients with an AHO phenotype and no hormone resistance and progressive osseous heteroplasia (POH) cases have inactivating paternally inherited GNAS mutations. METHODOLOGY/PRINCIPAL FINDINGS We here describe 17 subjects with an AHO-like phenotype that could be compatible with having PPHP but none of them carried Gsalpha mutations. Functional platelet studies however showed an obvious Gs hypofunction in the 13 patients that were available for testing. Methylation for the three differentially methylated GNAS regions was quantified via the Sequenom EpiTYPER. Patients showed significant hypermethylation of the XL amplicon compared to controls (36 ± 3 vs. 29 ± 3%; p<0.001); a pattern that is reversed to XL hypomethylation found in PHPIb. Interestingly, XL hypermethylation was associated with reduced XLalphaS protein levels in the patients' platelets. Methylation for NESP and ExonA/B was significantly different for some but not all patients, though most patients have site-specific CpG methylation abnormalities in these amplicons. Since some AHO features are present in other imprinting disorders, the methylation of IGF2, H19, SNURF and GRB10 was quantified. Surprisingly, significant IGF2 hypermethylation (20 ± 10 vs. 14 ± 7%; p<0.05) and SNURF hypomethylation (23 ± 6 vs. 32 6%; p<0.001) was found in patients vs. controls, while H19 and GRB10 methylation was normal. CONCLUSION/SIGNIFICANCE In conclusion, this is the first report of methylation defects including GNAS in patients with an AHO-like phenotype without endocrinological abnormalities. Additional studies are still needed to correlate the methylation defect with the clinical phenotype.
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Affiliation(s)
- Benedetta Izzi
- Center for Molecular and Vascular Biology, University of Leuven, Leuven, Belgium
| | - Inge Francois
- Departement of Pediatrics, University of Leuven, Leuven, Belgium
| | - Veerle Labarque
- Departement of Pediatrics, University of Leuven, Leuven, Belgium
| | - Chantal Thys
- Center for Molecular and Vascular Biology, University of Leuven, Leuven, Belgium
| | | | - Koen Devriendt
- Center for Human Genetics, University of Leuven, Leuven, Belgium
| | - Eric Legius
- Center for Human Genetics, University of Leuven, Leuven, Belgium
| | | | | | | | | | - Chris Van Geet
- Center for Molecular and Vascular Biology, University of Leuven, Leuven, Belgium
- Departement of Pediatrics, University of Leuven, Leuven, Belgium
| | - Kathleen Freson
- Center for Molecular and Vascular Biology, University of Leuven, Leuven, Belgium
- * E-mail:
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Fernández-Rebollo E, Maeda A, Reyes M, Turan S, Fröhlich LF, Plagge A, Kelsey G, Jüppner H, Bastepe M. Loss of XLαs (extra-large αs) imprinting results in early postnatal hypoglycemia and lethality in a mouse model of pseudohypoparathyroidism Ib. Proc Natl Acad Sci U S A 2012; 109:6638-43. [PMID: 22496590 PMCID: PMC3340037 DOI: 10.1073/pnas.1117608109] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Maternal deletion of the NESP55 differentially methylated region (DMR) (delNESP55/ASdel3-4(m), delNAS(m)) from the GNAS locus in humans causes autosomal dominant pseudohypoparathyroidism type Ib (AD-PHP-Ib(delNASm)), a disorder of proximal tubular parathyroid hormone (PTH) resistance associated with loss of maternal GNAS methylation imprints. Mice carrying a similar, maternally inherited deletion of the Nesp55 DMR (ΔNesp55(m)) replicate these Gnas epigenetic abnormalities and show evidence for PTH resistance, yet these mice demonstrate 100% mortality during the early postnatal period. We investigated whether the loss of extralarge αs (XLαs) imprinting and the resultant biallelic expression of XLαs are responsible for the early postnatal lethality in ΔNesp55(m) mice. First, we found that ΔNesp55(m) mice are hypoglycemic and have reduced stomach-to-body weight ratio. We then generated mice having the same epigenetic abnormalities as the ΔNesp55(m) mice but with normalized XLαs expression due to the paternal disruption of the exon giving rise to this Gnas product. These mice (ΔNesp55(m)/Gnasxl(m+/p-)) showed nearly 100% survival up to postnatal day 10, and a substantial number of them lived to adulthood. The hypoglycemia and reduced stomach-to-body weight ratio observed in 2-d-old ΔNesp55(m) mice were rescued in the ΔNesp55(m)/Gnasxl(m+/p-) mice. Surviving double-mutant animals had significantly reduced Gαs mRNA levels and showed hypocalcemia, hyperphosphatemia, and elevated PTH levels, thus providing a viable model of human AD-PHP-Ib. Our findings show that the hypoglycemia and early postnatal lethality caused by the maternal deletion of the Nesp55 DMR result from biallelic XLαs expression. The double-mutant mice will help elucidate the pathophysiological mechanisms underlying AD-PHP-Ib.
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Affiliation(s)
| | | | | | - Serap Turan
- Endocrine Unit, Department of Medicine, and
- Pediatric Endocrinology, Marmara University School of Medicine, Istanbul 34899, Turkey
| | - Leopold F. Fröhlich
- Endocrine Unit, Department of Medicine, and
- Institute of Pathology, Medical University of Graz, 8036 Graz, Austria
| | - Antonius Plagge
- Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool L69 3BX, United Kingdom
| | - Gavin Kelsey
- Epigenetics Programme, The Babraham Institute, Cambridge CB22 3AT, United Kingdom; and
- Centre for Trophoblast Research, University of Cambridge, Cambridge CB2 1TN, United Kingdom
| | - Harald Jüppner
- Endocrine Unit, Department of Medicine, and
- Pediatric Nephrology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114
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No evidence for GNAS copy number variants in patients with features of Albright's hereditary osteodystrophy and abnormal platelet Gs activity. J Hum Genet 2012; 57:277-9. [PMID: 22277900 DOI: 10.1038/jhg.2012.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Albright's hereditary osteodystrophy (AHO) is characterized by short stature, round face, calcifications, obesity, brachydactyly and intellectual disability. AHO without hormone resistance is called pseudopseudohypoparathyroidism (PPHP), a rare clinical condition difficult to diagnose with highly variable features. PPHP is caused by paternally inherited loss-of-function mutations in the GNAS. Patients with 2q37 microdeletions or HDAC4 mutations are also defined as having an AHO-like phenotype with normal stimulatory G (Gs) function. We have studied 256 patients with AHO features but no other diagnosis. Their platelet Gs activity was determined via the aggregation-inhibition test showing Gs hypo- or hyperfuncton in 24% and 15% of the patients, respectively. Before initiating with detailed (epi)genetic GNAS studies, we here wanted to excluded copy number variants (CNVs) in GNAS as cause of AHO with a novel large-scale screening technique. Multiplex amplicon quantification (MAQ) for CNVs screening was developed for the 20q13.3 region including GNAS and potential long-range imprinting control elements such as STX16. This is the first large-scale GNAS CNV study in patients with common AHO features but no CNVs were detected. In conclusion, CNVs in the GNAS region are not likely to cause an AHO-like phenotype with or without abnormal platelet Gs activity. Future studies will be undertaken to find out whether these AHO patients with abnormal Gs function are characterized by GNAS coding or methylation defects.
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Abstract
CONTEXT The term pseudohypoparathyroidism (PHP) indicates a group of heterogeneous disorders whose common feature is represented by impaired signaling of various hormones (primarily PTH) that activate cAMP-dependent pathways via Gsα protein. The two main subtypes of PHP, PHP type Ia, and Ib (PHP-Ia, PHP-Ib) are caused by molecular alterations within or upstream of the imprinted GNAS gene, which encodes Gsα and other translated and untranslated products. EVIDENCE ACQUISITION A PubMed search was used to identify the available studies (main query terms: pseudohypoparathyroidism; Albright hereditary osteodystrophy; GNAS; GNAS1; progressive osseous heteroplasia). The most relevant studies until February 2011 have been included in the review. EVIDENCE SYNTHESIS AND CONCLUSIONS Despite the first description of this disorder dates back to 1942, recent findings indicating complex epigenetic alterations beside classical mutations at the GNAS complex gene, pointed out the limitation of the actual classification of the disease, resulting in incorrect genetic counselling and diagnostic procedures, as well as the gap in our actual knowledge of the pathogenesis of these disorders. This review will focus on PHP type I, in particular its diagnosis, classification, treatment, and underlying molecular alterations.
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Affiliation(s)
- Giovanna Mantovani
- Endocrinology and Diabetology Unit, Department of Medical Sciences, Università degli Studi di Milano, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Ca' Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy.
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Kinoshita K, Minagawa M, Takatani T, Takatani R, Ohashi M, Kohno Y. Establishment of diagnosis by bisulfite-treated methylation-specific PCR method and analysis of clinical characteristics of pseudohypoparathyroidism type 1b. Endocr J 2011; 58:879-87. [PMID: 21836370 DOI: 10.1507/endocrj.k10e-364] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Pathogenesis of pseudohypoparathyroidism type 1b (PHP-1b) is related to the loss of methylation at the GNAS exon A/B region, which is combined with epigenetic defects at other differentially methylated GNAS regions in most sporadic cases. In this study, we established a method for evaluating the methylation status of a CpG island in exon A/B using a methylation-specific polymerase chain reaction (MSPCR). We designed two primer pairs specific for the methylated and unmethylated alleles and evaluated the methylation status of GNAS exon A/B in samples from PHP-1b patients and normal controls. We examined 20 Japanese patients and 20 normal controls, and one primer set was found to be appropriate for diagnosis. Furthermore, we evaluated the clinical data of patients. Weight and height of patients were not significantly different from the normal population. Short stature (adult height ≤ 2SD) was observed in one patient and short metacarpals in two. Obesity was observed in six patients, and no patient showed ectopic subcutaneous calcification. Seven patients showed subclinical hypothyroidism because of resistance to thyroid stimulating hormone, but no patient had an abnormally low free thyroxine level, and none received oral thyroid hormone replacement. For diagnosis of PHP-1b, only clinical data is not sufficient because a few PHP-1b patients show clinical features similar to PHP-1a, and hence, molecular biology techniques are required for correct diagnosis. We concluded that MSPCR is applicable for rapid molecular diagnosis of PHP-1b.
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Affiliation(s)
- Kaori Kinoshita
- Department of Pediatrics, Graduate School of Medicine, Chiba University, Chiba, Japan.
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Fernández-Rebollo E, Pérez de Nanclares G, Lecumberri B, Turan S, Anda E, Pérez-Nanclares G, Feig D, Nik-Zainal S, Bastepe M, Jüppner H. Exclusion of the GNAS locus in PHP-Ib patients with broad GNAS methylation changes: evidence for an autosomal recessive form of PHP-Ib? J Bone Miner Res 2011; 26:1854-63. [PMID: 21523828 PMCID: PMC3814169 DOI: 10.1002/jbmr.408] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Most patients with autosomal dominant pseudohypoparathyroidism type Ib (AD-PHP-Ib) carry maternally inherited microdeletions upstream of GNAS that are associated with loss of methylation restricted to GNAS exon A/B. Only few AD-PHP-Ib patients carry microdeletions within GNAS that are associated with loss of all maternal methylation imprints. These epigenetic changes are often indistinguishable from those observed in patients affected by an apparently sporadic PHP-Ib form that has not yet been defined genetically. We have now investigated six female patients affected by PHP-Ib (four unrelated and two sisters) with complete or almost complete loss of GNAS methylation, whose healthy children (11 in total) showed no epigenetic changes at this locus. Analysis of several microsatellite markers throughout the 20q13 region made it unlikely that PHP-Ib is caused in these patients by large deletions involving GNAS or by paternal uniparental isodisomy or heterodisomy of chromosome 20 (patUPD20). Microsatellite and single-nucleotide variation (SNV) data revealed that the two affected sisters share their maternally inherited GNAS alleles with unaffected relatives that lack evidence for abnormal GNAS methylation, thus excluding linkage to this locus. Consistent with these findings, healthy children of two unrelated sporadic PHP-Ib patients had inherited different maternal GNAS alleles, also arguing against linkage to this locus. Based on our data, it appears plausible that some forms of PHP-Ib are caused by homozygous or compound heterozygous mutation(s) in an unknown gene involved in establishing or maintaining GNAS methylation.
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Affiliation(s)
- Eduardo Fernández-Rebollo
- Endocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
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Jin HY, Lee BH, Choi JH, Kim GH, Kim JK, Lee JH, Yu J, Yoo JH, Ko CW, Lim HH, Chung HR, Yoo HW. Clinical characterization and identification of two novel mutations of the GNAS gene in patients with pseudohypoparathyroidism and pseudopseudohypoparathyroidism. Clin Endocrinol (Oxf) 2011; 75:207-13. [PMID: 21521295 DOI: 10.1111/j.1365-2265.2011.04026.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
OBJECTIVE Pseudohypoparathyroidism (PHP) and pseudopseudohypoparathyroidism (PPHP) are rare disorders resulting from genetic and epigenetic aberrations in the GNAS locus. DESIGN Investigation of clinical characteristics and molecular analysis in PHP and PPHP. PATIENTS Fourteen subjects from 13 unrelated families including subjects with PPHP (n = 1), PHP-Ia (n = 6) and PHP-Ib (n = 7) were enrolled. MEASUREMENTS Clinical data, including age at presentation, presenting symptom, auxological findings, family history, presence of Albright hereditary osteodystrophy (AHO) features and hormonal and biochemical findings, were analysed. The GNAS locus was subjected to direct sequencing and methylation analysis using methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA). RESULTS Of the 13 PHP subjects, 10 (three PHP-Ia and seven PHP-Ib) presented with hypocalcemic tetany at ages ranging from 7 to 14·8 years. Subcutaneous calcification was observed as an early manifestation of AHO in one PHP-Ia patient (age, 2·9 years) and one PPHP patient (age, 7 months). Six PHP-Ia and one PPHP harboured four different heterozygous mutations within the coding region of GNAS, p.Asp189_Tyr190delinsMetfxX14, p.Val117fsX23, p.Tyr190CysfsX19, and a splicing mutation (c.659 + 1G>A), of which the latter two were novel. Five subjects with PHP-Ib exhibited complete loss of the maternal-specific methylation pattern. The remaining two PHP-Ib showed a loss of methylation of exon 1A on the maternal allele as a consequence of heterozygous 3-kb microdeletions within the STX16 gene. CONCLUSIONS GNAS mutation analyses and MS-MLPA assays are useful molecular tools for understanding the molecular bases and confirming the diagnosis of PHP and PPHP.
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Affiliation(s)
- Hye Young Jin
- Department of Pediatrics, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, Korea
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Zazo C, Thiele S, Martín C, Fernandez-Rebollo E, Martinez-Indart L, Werner R, Garin I, Hiort O, Perez de Nanclares G. Gsα activity is reduced in erythrocyte membranes of patients with psedohypoparathyroidism due to epigenetic alterations at the GNAS locus. J Bone Miner Res 2011; 26:1864-70. [PMID: 21351142 DOI: 10.1002/jbmr.369] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
In pseudohypoparathyroidism (PHP), PTH resistance results from impairment of signal transduction of G protein-coupled receptors caused by a deficiency of the Gsα-cAMP signaling cascade due to diminished Gsα activity in maternally imprinted tissues. In PHP-Ia, inactivating mutations of the GNAS gene lead to haploinsufficiency in some tissues with biallelic expression, so in addition to PHP, Albright's hereditary osteodystrophy (AHO) is also present. In PHP-Ib, caused by methylation defects at the GNAS locus, diminished Gsα activity was thought to be limited to maternally imprinted tissues, such as the renal proximal tubule and the thyroid, leading to a lack of AHO. Recently, we demonstrated methylation defects in patients with AHO signs, indicating a connection between epigenetic changes and AHO. Our objective was to determine Gsα activity in erythrocyte membranes in patients with epigenetic defects at the GNAS locus compared to normal controls and patients with inactivating GNAS mutations. Gsα activity and expression, mutation of the GNAS locus, and methylation status were studied in patients with PHP and mild signs of AHO (PHP-Ia: 12; PHP-Ib: 17, of which 8 had some features of AHO). Then, we statistically compared the Gsα activity of the different PHP subtypes. Patients with methylation defects at the GNAS locus show a significant decrease in erythrocyte Gsα activity compared to normal controls (PHP-Ib versus controls, p < .001). This was significantly lower in patients with AHO signs (PHP-Ib + mild-AHO versus PHP-Ib, p < .05). Our research shows that PHP-Ia and PHP-Ib classification is not only overlapped genetically, as reported, but also in terms of Gsα activity. Reduced expression of GNAS due to methylation defects could downregulate Gsα activity in other tissues beyond those described and could also be causative of AHO.
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Affiliation(s)
- Celia Zazo
- Molecular Genetics Laboratory, Research Unit, Hospital Txagorritxu, Vitoria-Gasteiz, Spain
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Bastepe M. The GNAS Locus: Quintessential Complex Gene Encoding Gsalpha, XLalphas, and other Imprinted Transcripts. Curr Genomics 2011; 8:398-414. [PMID: 19412439 PMCID: PMC2671723 DOI: 10.2174/138920207783406488] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2007] [Revised: 09/22/2007] [Accepted: 09/28/2007] [Indexed: 12/14/2022] Open
Abstract
The currently estimated number of genes in the human genome is much smaller than previously predicted. As an explanation for this disparity, most individual genes have multiple transcriptional units that represent a variety of biologically important gene products. GNAS exemplifies a gene of such complexity. One of its products is the alpha-subunit of the stimulatory heterotrimeric G protein (Gsalpha), a ubiquitous signaling protein essential for numerous different cellular responses. Loss-of-function and gain-of-function mutations within Gsalpha-coding GNAS exons are found in various human disorders, including Albright's hereditary osteodystrophy, pseudohypoparathyroidism, fibrous dysplasia of bone, and some tumors of different origin. While Gsalpha expression in most tissues is biallelic, paternal Gsalpha expression is silenced in a small number of tissues, playing an important role in the development of phenotypes associated with GNAS mutations. Additional products derived exclusively from the paternal GNAS allele include XLalphas, a protein partially identical to Gsalpha, and two non-coding RNA molecules, the A/B transcript and the antisense transcript. The maternal GNAS allele leads to NESP55, a chromogranin-like neuroendocrine secretory protein. In vivo animal models have demonstrated the importance of each of the exclusively imprinted GNAS products in normal mammalian physiology. However, although one or more of these products are also disrupted by most naturally occurring GNAS mutations, their roles in disease pathogenesis remain unknown. To further our understanding of the significance of this gene in physiology and pathophysiology, it will be important to elucidate the cellular roles and the mechanisms regulating the expression of each GNAS product.
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Affiliation(s)
- Murat Bastepe
- Endocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
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Xu H, Zhao Y, Liu Z, Zhu W, Zhou Y, Zhao Z. Bisulfite genomic sequencing of DNA from dried blood spot microvolume samples. Forensic Sci Int Genet 2011; 6:306-9. [PMID: 21737370 DOI: 10.1016/j.fsigen.2011.06.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2010] [Revised: 04/16/2011] [Accepted: 06/13/2011] [Indexed: 10/18/2022]
Abstract
DNA methylation is an important event in epigenetic changes in cells, and a fundamental regulator of gene transcription. Bisulfite genomic sequencing is a powerful technique used in studies of DNA methylation. However, the established procedures often require relatively large amounts of DNA. In everyday practice, samples submitted for analysis might contain very small amounts of poor quality material, as is often the case with forensic stain samples. In this study, we assess a modified, more efficient method of bisulfite genomic sequencing. Genomic DNA extracted from 3-mm dried blood spots using QIAamp micro kit was treated with sodium bisulfite (using EpiTect kit). Subsequent methylation-specific PCR (MSP) followed by DNA sequencing displayed the differentially methylated region of imprinted gene SNRPN. Our results show that this new combination of efficient DNA extraction and bisulfite treatment provides high quality conversion of unmethylated cytosine to uracil for bisulfite genomic sequencing analysis. This reliable method substantially improves the DNA methylation analysis of forensic stain samples.
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Affiliation(s)
- Hongmei Xu
- Department of Forensic Medicine, Shanghai Medical College, Fudan University, 138 Yixueyuan Road, Shanghai 200032, China
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Effects of deficiency of the G protein Gsα on energy and glucose homeostasis. Eur J Pharmacol 2011; 660:119-24. [PMID: 21208600 DOI: 10.1016/j.ejphar.2010.10.105] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2010] [Revised: 09/24/2010] [Accepted: 10/12/2010] [Indexed: 02/07/2023]
Abstract
G(s)α is a ubiquitously expressed G protein α-subunit that couples receptors to the generation of intracellular cyclic AMP. The G(s)α gene GNAS is a complex gene that undergoes genomic imprinting, an epigenetic phenomenon that leads to differential expression from the two parental alleles. G(s)α is imprinted in a tissue-specific manner, being expressed primarily from the maternal allele in a small number of tissues. Albright hereditary osteodystrophy is a monogenic obesity disorder caused by heterozygous G(s)α mutations but only when the mutations are maternally inherited. Studies in mice indicate a similar parent-of-origin effect on energy and glucose metabolism, with maternal but not paternal mutations leading to obesity, reduced sympathetic nerve activity and energy expenditure, glucose intolerance and insulin resistance, with no primary effect on food intake. These effects result from G(s)α imprinting leading to severe G(s)α deficiency in one or more regions of the central nervous system, and are associated with a specific defect in melanocortins to stimulate sympathetic nerve activity and energy expenditure.
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Wilkins JF, Úbeda F. Diseases associated with genomic imprinting. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2011; 101:401-45. [PMID: 21507360 DOI: 10.1016/b978-0-12-387685-0.00013-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Genomic imprinting is the phenomenon where the expression of a locus differs between the maternally and paternally inherited alleles. Typically, this manifests as transcriptional silencing of one of the alleles, although many genes are imprinted in a tissue- or isoform-specific manner. Diseases associated with imprinted genes include various cancers, disorders of growth and metabolism, and disorders in neurodevelopment, cognition, and behavior, including certain major psychiatric disorders. In many cases, the disease phenotypes associated with dysfunction at particular imprinted loci can be understood in terms of the evolutionary processes responsible for the origin of imprinting. Imprinted gene expression represents the outcome of an intragenomic evolutionary conflict, where natural selection favors different expression strategies for maternally and paternally inherited alleles. This conflict is reasonably well understood in the context of the early growth effects of imprinted genes, where paternally inherited alleles are selected to place a greater demand on maternal resources than are maternally inherited alleles. Less well understood are the origins of imprinted gene expression in the brain, and their effects on cognition and behavior. This chapter reviews the genetic diseases that are associated with imprinted genes, framed in terms of the evolutionary pressures acting on gene expression at those loci. We begin by reviewing the phenomenon and evolutionary origins of genomic imprinting. We then discuss diseases that are associated with genetic or epigenetic defects at particular imprinted loci, many of which are associated with abnormalities in growth and/or feeding behaviors that can be understood in terms of the asymmetric pressures of natural selection on maternally and paternally inherited alleles. We next described the evidence for imprinted gene effects on adult cognition and behavior, and the possible role of imprinted genes in the etiology of certain major psychiatric disorders. Finally, we conclude with a discussion of how imprinting, and the evolutionary-genetic conflicts that underlie it, may enhance both the frequency and morbidity of certain types of diseases.
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Izzi B, Decallonne B, Devriendt K, Bouillon R, Vanderschueren D, Levtchenko E, de Zegher F, Van den Bruel A, Lambrechts D, Van Geet C, Freson K. A new approach to imprinting mutation detection in GNAS by Sequenom EpiTYPER system. Clin Chim Acta 2010; 411:2033-9. [PMID: 20807523 DOI: 10.1016/j.cca.2010.08.034] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2010] [Revised: 08/19/2010] [Accepted: 08/24/2010] [Indexed: 11/28/2022]
Abstract
BACKGROUND Pseudohypoparathyroidism type Ib (PHPIb) results from abnormal imprinting of GNAS. Familial and sporadic forms of PHPIb have distinct GNAS imprinting patterns: familial PHPIb patients have an exon A/B-only imprinting defect and an intragenic STX16 deletion, whereas sporadic PHPIb cases have abnormal imprinting of the three differentially methylated regions (DMRs) in GNAS without the STX16 deletion. Overall GNAS methylation defects have recently been detected in some PHPIa patients. METHODS This study describes the first quantitative methylation analysis of multiple CpG sites for three different GNAS DMRs using the Sequenom EpiTYPER in 35 controls, 12 PHPIb patients, 2 PHPIa patients and 2 patients without parathormone (PTH) resistance but having only hypocalcemia and hyperphosphatemia. RESULTS All patients have GNAS methylation defects typically with NESP hypermethylation versus XL and exon A/B hypomethylation while the imprinting of SNURF/SNRPN was normal. PHPIa patients showed an abnormal methylation in the three DMRs of GNAS. For the first time, a marked abnormal GNAS methylation was also found in 2 patients without PTH resistance but having hypocalcemia and hyperphosphatemia. CONCLUSIONS The Sequenom EpiTYPER proves to be very sensitive in detecting DNA methylation changes. Our analysis also suggests that GNAS imprinting defects might be more frequent and diverse than previously thought.
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Affiliation(s)
- Benedetta Izzi
- Center for Molecular and Vascular Biology, University of Leuven, Leuven, 3000, Belgium
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Kelsey G. Imprinting on chromosome 20: Tissue-specific imprinting and imprinting mutations in the GNAS locus. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2010; 154C:377-86. [DOI: 10.1002/ajmg.c.30271] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Chillambhi S, Turan S, Hwang DY, Chen HC, Jüppner H, Bastepe M. Deletion of the noncoding GNAS antisense transcript causes pseudohypoparathyroidism type Ib and biparental defects of GNAS methylation in cis. J Clin Endocrinol Metab 2010; 95:3993-4002. [PMID: 20444925 PMCID: PMC2913043 DOI: 10.1210/jc.2009-2205] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
CONTEXT GNAS encodes the alpha-subunit of the stimulatory G protein as well as additional imprinted transcripts including the maternally expressed NESP55 and the paternally expressed XLalphas, antisense, and A/B transcripts. Most patients with pseudohypoparathyroidism type Ib (PHP-Ib) exhibit imprinting defects affecting the maternal GNAS allele, which are thought to reduce/abolish Gsalpha expression in renal proximal tubules and thereby cause resistance to PTH. OBJECTIVE Our objective was to define the genetic defect in a previously unreported family with autosomal dominant PHP-Ib. DESIGN AND SETTING Analyses of serum and urine chemistries and of genomic DNA and lymphoblastoid-derived RNA were conducted at a tertiary hospital and research laboratory. PATIENTS Affected individuals presented with muscle weakness and/or paresthesia and showed hypocalcemia, hyperphosphatemia, and elevated serum PTH. Obligate carriers were healthy and revealed no obvious abnormality in mineral ion homeostasis. RESULTS A novel 4.2-kb microdeletion was discovered in the affected individuals and the obligate carriers, ablating two noncoding GNAS antisense exons while preserving the NESP55 exon. On maternal transmission, the deletion causes loss of all maternal GNAS imprints, partial gain of NESP55 methylation, and PTH resistance. Paternal transmission of the mutation leads to epigenetic alterations in cis, including a partial loss of NESP55 methylation and a partial gain of A/B methylation. CONCLUSIONS The identified deletion points to a unique cis-acting element located telomeric of the NESP55 exon that is critical for imprinting both GNAS alleles. These findings provide novel insights into the molecular mechanisms underlying PHP and GNAS imprinting.
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Affiliation(s)
- Smitha Chillambhi
- Endocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, 50 Blossom Street Thier 10, Boston, Massachusetts 02114, USA
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