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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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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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Abstract
Imprinting disorders are a group of congenital diseases caused by dysregulation of genomic imprinting, affecting prenatal and postnatal growth, neurocognitive development, metabolism and cancer predisposition. Aberrant expression of imprinted genes can be achieved through different mechanisms, classified into epigenetic - if not involving DNA sequence change - or genetic in the case of altered genomic sequence. Despite the underlying mechanism, the phenotype depends on the parental allele affected and opposite phenotypes may result depending on the involvement of the maternal or the paternal chromosome. Imprinting disorders are largely underdiagnosed because of the broad range of clinical signs, the overlap of presentation among different disorders, the presence of mild phenotypes, the mitigation of the phenotype with age and the limited availability of molecular techniques employed for diagnosis. This review briefly illustrates the currently known human imprinting disorders, highlighting endocrinological aspects of pediatric interest.
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Affiliation(s)
- Diana Carli
- University of Torino, Department of Pediatric and Public Health Sciences, Torino, Italy
| | - Evelise Riberi
- University of Torino, Department of Pediatric and Public Health Sciences, Torino, Italy
| | | | - Alessandro Mussa
- University of Torino, Department of Pediatric and Public Health Sciences, Torino, Italy,* Address for Correspondence: University of Torino, Department of Pediatric and Public Health Sciences, Torino, Italy Phone: +39-011-313-1985 E-mail:
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Todorova-Koteva K, Wood K, Imam S, Jaume JC. Screening for parathyroid hormone resistance in patients with nonphenotypically evident pseudohypoparathyroidism. Endocr Pract 2013; 18:864-9. [PMID: 22784837 DOI: 10.4158/ep12007.or] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
OBJECTIVE Hypocalcemia and hyperphosphatemia in the setting of elevated parathyroid hormone (PTH) and normal vitamin D metabolites, raises the possibility of PTH resistance. The idiopathic and inherited forms of PTH resistance are referred to as pseudohypoparathyroidism. Nonphenotypically evident pseudohypoparathyroidism can go undiagnosed for decades. We have designed a new test to diagnose PTH resistance and confirmed its clinical utility in the diagnosis of pseudohypoparathyroidism. METHODS Our test consists of a subcutaneous injection of commercially available recombinant PTH and concomitant measurement of cyclic adenosine monophosphate in urine. We implemented the test in 2 patients with recalcitrant hypocalcemia and a healthy control subject. RESULTS Our test unequivocally demonstrated PTH resistance in both patients. One of the patients had phenotypically evident pseudohypoparathyroidism type-1a hence, PTH resistance was suspected. The other patient with nonphenotypically evident disease, also showed PTH resistance and was later demonstrated to have pseudohypoparathyroidism type-1b at the genomic level and confirmed to be of familial type. CONCLUSION Our results show for the first time the implementation of a simple new diagnostic tool designed to check for PTH resistance. This new test has already proven to be useful in few occasions at our institution. Larger populations, however, should be tested before implementation of such a test is considered a standard of care.
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Affiliation(s)
- Kristina Todorova-Koteva
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, School of Medicine and Veterans Affairs Medical Center, University of Wisconsin-Madison, Madison, Wisconsin 53792-5148, 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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Thiele S, de Sanctis L, Werner R, Grötzinger J, Aydin C, Jüppner H, Bastepe M, Hiort O. Functional characterization of GNAS mutations found in patients with pseudohypoparathyroidism type Ic defines a new subgroup of pseudohypoparathyroidism affecting selectively Gsα-receptor interaction. Hum Mutat 2011; 32:653-60. [PMID: 21488135 DOI: 10.1002/humu.21489] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2010] [Accepted: 02/09/2011] [Indexed: 01/09/2023]
Abstract
Pseudohypoparathyroidism type Ia (PHPIa) is caused by GNAS mutations leading to deficiency of the α-subunit of stimulatory G proteins (Gsα) that mediate signal transduction of G protein-coupled receptors via cAMP. PHP type Ic (PHPIc) and PHPIa share clinical features of Albright hereditary osteodystrophy (AHO); however, in vitro activity of solubilized Gsα protein is normal in PHPIc but reduced in PHPIa. We screened 32 patients classified as PHPIc for GNAS mutations and identified three mutations (p.E392K, p.E392X, p.L388R) in four unrelated families. These and one novel mutation associated with PHPIa (p.L388P) were introduced into a pcDNA3.1(-) expression vector encoding Gsα wild-type and expressed in a Gsα-null cell line (Gnas(E2-/E2-) ). To investigate receptor-mediated cAMP accumulation, we stimulated the endogenous expressed β(2) -adrenergic receptor, or the coexpressed PTH or TSH receptors, and measured the synthesized cAMP by RIA. The results were compared to receptor-independent cholera toxin-induced cAMP accumulation. Each of the mutants associated with PHPIc significantly reduced or completely disrupted receptor-mediated activation, but displayed normal receptor-independent activation. In contrast, PHPIa associated p.L388P disrupted both receptor-mediated activation and receptor-independent activation. We present a new subgroup of PHP that is caused by Gsα deficiency and selectively affects receptor coupling functions of Gsα.
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Affiliation(s)
- Susanne Thiele
- Department of Pediatrics and Adolescent Medicine, University of Lübeck, Germany.
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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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Abstract
CONTEXT The biochemical hallmark of pseudohypoparathyroidism type 1a (PHP1a) is resistance to PTH, but based on tissue-specific imprinting of GNAS, PTH resistance may be limited to the renal cortex. Some studies have shown that bone is responsive to PTH, suggesting that PHP1a patients with chronically elevated PTH levels may have low bone mineral density (BMD). SETTING This observational study was conducted at the Institute of Clinical and Translational Research, Johns Hopkins Medical Institutions. SUBJECTS Twenty-two children and adults with PHP1a were studied. MAIN OUTCOME MEASURE The main outcome measure was BMD Z-score at the lumbar spine (LS), total hip, femoral neck, and total body using dual-energy x-ray absorptiometry, relative to height, weight, and pubertal status. RESULTS The mean (+/-SD) Z-score for height was 0.77 +/- 1.66 and 1.85 +/- 1.15 for BMI. The BMD Z-score at each of the four sites studied was as follows: LS, 0.29 +/- 1.08; total hip, 0.27 +/- 1.24; femoral neck, 0.02 +/- 1.26; and total body, 0.98 +/- 1.50. Only two subjects (9%) had BMD Z-scores less than -2, and each had additional risk factors for low BMD. BMD in total body and LS spine corrected for height-for-age Z-score was significantly greater than normal. There was no correlation between PTH level and BMD Z-score or between body mass index and BMD Z-score. CONCLUSIONS Despite secondary hyperparathyroidism, region-specific BMD is not reduced in patients with PHP1a, and total body BMD is significantly greater than normal.
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Affiliation(s)
- Dominique N Long
- Division of Pediatric Endocrinology, Department of Pediatrics, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
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Sun MT, Yang SS, Juan CJ, Lin SH. Symmetrical brain calcifications. Am J Med 2010; 123:131-3. [PMID: 20103021 DOI: 10.1016/j.amjmed.2009.12.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2008] [Revised: 12/03/2009] [Accepted: 12/03/2009] [Indexed: 01/16/2023]
Affiliation(s)
- Ming-Tsung Sun
- Department of Internal Medicine, Hualien Armed Forces General Hospital, Hualien, Taiwan
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Freson K, Izzi B, Labarque V, Van Helvoirt M, Thys C, Wittevrongel C, Bex M, Bouillon R, Godefroid N, Proesmans W, de Zegher F, Jaeken J, Van Geet C. GNAS defects identified by stimulatory G protein alpha-subunit signalling studies in platelets. J Clin Endocrinol Metab 2008; 93:4851-9. [PMID: 18812479 DOI: 10.1210/jc.2008-0883] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
CONTEXT GNAS is an imprinted region that gives rise to several transcripts, antisense transcripts, and noncoding RNAs, including transcription of RNA encoding the alpha-subunit of the stimulatory G protein (Gsalpha). The complexity of the GNAS cluster results in ubiquitous genomic imprints, tissue-specific Gsalpha expression, and multiple genotype-phenotype relationships. Phenotypes resulting from genetic and epigenetic abnormalities of the GNAS region include Albright's hereditary osteodystrophy, pseudohypoparathyroidism types Ia (PHPIa) and Ib (PHPIb), and pseudopseudohypoparathyroidism (PPHP). OBJECTIVE The aim was to study the complex GNAS pathology by a functional test as an alternative to the generally used but labor-intensive erythrocyte complementation assay. DESIGN AND PATIENTS We report the first platelet-based diagnostic test for Gsalpha hypofunction, supported by clinical, biochemical, and molecular data for six patients with PHPIa or PPHP and nine patients with PHPIb. The platelet test is based on the inhibition of platelet aggregation by cAMP, produced after Gsalpha stimulation. RESULTS Platelets are easily accessible, and platelet aggregation responses were found to reflect Gsalpha signaling defects in patients, in concordance with the patient's phenotype and genotype. Gsalpha hypofunction in PHPIa and PPHP patients with GNAS mutations was clearly detected by this method. Mildly decreased or normal Gsalpha function was detected in patients with PHPIb with either an overall or exon 1A-only epigenetic defect, respectively. Platelet Gsalpha expression was reduced in both PHPIb patient groups, whereas XLalphas was up-regulated only in PHPIb patients with the broad epigenetic defect. CONCLUSION The platelet-based test is a novel tool for establishing the diagnosis of Gsalpha defects, which may otherwise be quite challenging.
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Affiliation(s)
- Kathleen Freson
- Center for Molecular and Vascular Biology, University of Leuven, Herestraat 49, B-3000 Leuven, Belgium.
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Faissolle P, Wagner-Mahler K, Mas JC, Moreigne M, Khalfi A, Léonetti V, Silvy M, Barlier A, Giudicelli H. Une cause de calcifications intracérébrales à connaître : la pseudohypoparathyroïdie de type Ib. Arch Pediatr 2008; 15:1433-6. [DOI: 10.1016/j.arcped.2008.06.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2007] [Revised: 04/24/2008] [Accepted: 06/19/2008] [Indexed: 12/22/2022]
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Weinhaeusel A, Thiele S, Hofner M, Hiort O, Noehammer C. PCR-based analysis of differentially methylated regions of GNAS enables convenient diagnostic testing of pseudohypoparathyroidism type Ib. Clin Chem 2008; 54:1537-45. [PMID: 18617581 DOI: 10.1373/clinchem.2008.104216] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Pseudohypoparathyroidism type Ib (PHPIb) is characterized by parathyroid hormone (PTH) resistance, which can lead to hypocalcemia, hyperphosphatemia, and increased serum PTH. The disorder is caused by mutations in regulatory regions of the GNAS gene (GNAS complex locus) that lead to interferences in the methylation status of alternative GNAS promoters, such as exon A/B, NESP55, and XL alpha-s. PHPIb comprises disorders that show distinctive changes in methylation status but share the same clinical phenotype: (a) loss of methylation only at exon A/B of the GNAS gene and involving no other obvious epigenetic abnormalities [e.g., those caused by heterozygous microdeletions in the STX16 (syntaxin 16) region and found in many patients with autosomal dominant (AD) PHPIb]; (b) methylation abnormalities at several differentially methylated regions (DMRs), which are observed in most patients with sporadic PHPIb and some families with AD PHPIb. METHODS To permit early and reliable diagnosis of suspected PHPIb, we designed methylation-sensitive restriction enzyme-based and bisulfite deamination-based PCR tests for exon A/B and NESP55 DMRs. RESULTS Both PCR strategies permit proper methylation testing of GNAS and NESP55 DMRs and elucidate different disease subtypes. We have identified a novel microsatellite repeat polymorphism within GNAS exon A/B, and pedigree analyses have shown its presence to be conclusive evidence for familial disease. CONCLUSIONS We provide a simple diagnostic test for PHPIb, an imprinting disorder caused by different molecular changes within the GNAS complex locus. PHPIb, a complex and diagnostically challenging clinical phenotype, can be treated successfully by taking steps before the manifestation of symptoms to avoid clinical complications in affected patients or asymptomatic members of affected families who show positive results in genetic tests.
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Affiliation(s)
- Andreas Weinhaeusel
- Austrian Research Centers GmbH-ARC, Molecular Diagnostics, Seibersdorf, Austria.
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Lietman SA, Goldfarb J, Desai N, Levine MA. Preimplantation genetic diagnosis for severe albright hereditary osteodystrophy. J Clin Endocrinol Metab 2008; 93:901-4. [PMID: 18089698 PMCID: PMC2266954 DOI: 10.1210/jc.2007-2040] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Preimplantation genetic diagnosis (PGD) enables the selection of embryos without mutations for implantation and has not been described to our knowledge for mutations in GNAS. Phocomelia in a patient with Albright hereditary osteodystrophy (AHO) has also not been previously described. OBJECTIVE The aim of this study was to identify a GNAS mutation in a patient with a severe form of AHO and pseudohypoparathyroidism type 1a with phocomelia and to perform PGD on embryos derived by in vitro fertilization to deliver an unaffected infant. DESIGN A proband and his family are described clinically, the GNAS gene was sequenced to identify a novel mutation in the proband, and PGD was performed on embryos. SETTING The setting was in a tertiary-care hospital. PATIENTS The patients were from a single family in which the proband has a severe form of AHO. INTERVENTIONS Interventions were PGD and in vitro fertilization. MAIN OUTCOME MEASURES The main outcome measures were the clinical phenotypes and GNAS gene sequences of the proband, embryos, and family members. RESULTS After PGD, three genotypically normal embryos were transferred back to the mother. Pregnancy ensued, and a healthy male infant was delivered at 36.5 wk gestation. The GNAS genes in the baby were confirmed as wild-type, and the infant is free of any signs of AHO. CONCLUSIONS We describe herein a proband with AHO and severe skeletal deformities (including phocomelia) related to a novel GNAS mutation and the delivery of a male infant with homozygous normal GNAS genotype after PGD.
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Affiliation(s)
- Steven A Lietman
- Department of Orthopedic Surgery, Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA.
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