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Hannah-Shmouni F, Stratakis CA. An overview of inborn errors of metabolism manifesting with primary adrenal insufficiency. Rev Endocr Metab Disord 2018; 19:53-67. [PMID: 29956047 PMCID: PMC6204320 DOI: 10.1007/s11154-018-9447-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Primary adrenal insufficiency (PAI) results from an inability to produce adequate amounts of steroid hormones from the adrenal cortex. The most common causes of PAI are autoimmune adrenalitis (Addison's disease), infectious diseases, adrenalectomy, neoplasia, medications, and various rare genetic syndromes and inborn errors of metabolism that typically present in childhood although late-onset presentations are becoming increasingly recognized. The prevalence of PAI in Western countries is approximately 140 cases per million, with an incidence of 4 per 1,000,000 per year. Several pitfalls in the genetic diagnosis of patients with PAI exist. In this review, we provide an in-depth discussion and overview on the inborn errors of metabolism manifesting with PAI, including genetic diagnosis, genotype-phenotype relationships and counseling of patients and their families with a focus on various enzymatic deficiencies of steroidogenesis.
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Affiliation(s)
- Fady Hannah-Shmouni
- Section on Endocrinology & Genetics, The Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Building 10, CRC, Room 1-3330, 10 Center Dr., MSC1103, Bethesda, MD, 20892, USA
| | - Constantine A Stratakis
- Section on Endocrinology & Genetics, The Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Building 10, CRC, Room 1-3330, 10 Center Dr., MSC1103, Bethesda, MD, 20892, USA.
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Abstract
Congenital adrenal hyperplasia (CAH) refers to a group of autosomal recessive disorders due to single-gene defects in the various enzymes required for cortisol biosynthesis. CAH represents a continuous phenotypic spectrum with more than 95% of all cases caused by 21-hydroxylase deficiency. Genotyping is an important tool in confirming the diagnosis or carrier state, provides prognostic information on disease severity, and is essential for genetic counseling. In this article, the authors provide an in-depth discussion on the genetics of CAH, including genetic diagnosis, molecular analysis, genotype-phenotype relationships, and counseling of patients and their families.
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Affiliation(s)
- Fady Hannah-Shmouni
- Section on Endocrinology and Genetics, The Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Building 10, CRC, Room 1-2740, 10 Center Drive, MSC 1932, Bethesda, MD 20892-1932, USA
| | - Wuyan Chen
- Clinical DNA Testing and DNA Banking, PreventionGenetics, 3800 South Business Park Avenue, Marshfield, WI 54449, USA
| | - Deborah P Merke
- Section on Endocrinology and Genetics, The Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Building 10, CRC, Room 1-2740, 10 Center Drive, MSC 1932, Bethesda, MD 20892-1932, USA; Department of Pediatrics, The National Institutes of Health Clinical Center, 10 Center Drive, Bethesda, MD 20892-1932, USA.
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Coeli-Lacchini FB, Turatti W, Elias PCL, Elias LLK, Martinelli CE, Moreira AC, Antonini SR, de Castro M. A rational, non-radioactive strategy for the molecular diagnosis of congenital adrenal hyperplasia due to 21-hydroxylase deficiency. Gene 2013; 526:239-45. [DOI: 10.1016/j.gene.2013.03.082] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Revised: 03/12/2013] [Accepted: 03/17/2013] [Indexed: 11/24/2022]
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Shammas C, Neocleous V, Toumba M, Costi C, Phedonos AA, Efstathiou E, Kyriakou A, Phylactou LA, Skordis N. Overview of Genetic Defects in Endocrinopathies in the Island of Cyprus; Evidence of a Founder Effect. Genet Test Mol Biomarkers 2012; 16:1073-9. [DOI: 10.1089/gtmb.2011.0381] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Christos Shammas
- Department of Molecular Genetics, Function and Therapy, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Vassos Neocleous
- Department of Molecular Genetics, Function and Therapy, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Meropi Toumba
- Paediatric Endocrine Unit, Department of Paediatrics, Makarios III Hospital, Nicosia, Cyprus
| | - Constantina Costi
- Department of Molecular Genetics, Function and Therapy, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Alexia A.P. Phedonos
- Department of Molecular Genetics, Function and Therapy, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Elisavet Efstathiou
- Paediatric Endocrine Unit, Department of Paediatrics, Makarios III Hospital, Nicosia, Cyprus
| | - Andreas Kyriakou
- Paediatric Endocrine Unit, Department of Paediatrics, Makarios III Hospital, Nicosia, Cyprus
| | - Leonidas A. Phylactou
- Department of Molecular Genetics, Function and Therapy, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Nicos Skordis
- Department of Molecular Genetics, Function and Therapy, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
- Paediatric Endocrine Unit, Department of Paediatrics, Makarios III Hospital, Nicosia, Cyprus
- St. George's University of London Medical School at the University of Nicosia, Nicosia, Cyprus
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Marino R, Ramirez P, Galeano J, Perez Garrido N, Rocco C, Ciaccio M, Warman DM, Guercio G, Chaler E, Maceiras M, Bergadá I, Gryngarten M, Balbi V, Pardes E, Rivarola MA, Belgorosky A. Steroid 21-hydroxylase gene mutational spectrum in 454 Argentinean patients: genotype-phenotype correlation in a large cohort of patients with congenital adrenal hyperplasia. Clin Endocrinol (Oxf) 2011; 75:427-35. [PMID: 21609351 DOI: 10.1111/j.1365-2265.2011.04123.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
OBJECTIVE To report genotype-phenotype correlation in a large cohort of patients. CONTEXT Study of the CYP21A2 gene in 866 unrelated chromosomes of 21-hydroxylase deficiency in Argentinean patients with classic and nonclassic (NC) forms of congenital adrenal hyperplasia (CAH). METHODS Eleven most common mutations were analysed by allele-specific polymerase chain reaction, restriction fragment length polymorphism (RFLP) or southern blot analysis. Gene sequencing was performed when no mutation was detected in one allele or the genotype-phenotype correlation was lacking. RESULTS The 11-most-common-mutation screening allowed for the detection of 88·1% of affected alleles (80·3% in the NC and 95·2% in the classic forms). p.V281L, IVS2-13A/C>G (In2) and gene deletions and large gene conversions were the most prevalent mutations. In2 (35·2%) in salt wasting (SW), p.I172N (37·3%) in simple virilizing and p.V281L (54·1%) in NC CAH were the most prevalent mutations within the clinical forms. In 7/15 p.P30L mutation alleles, a chimeric CYP21A1P/CYP21A2 gene [PromCYP21A1P; p.P30L] was detected, while 6/15 represented a single-nucleotide substitution, and in 2/15 linkage with mutations, p.[P30L; V281L] and [p.P30L; IVS2-13A/C > G; p.Q318X] was found. In two SW patients, a novel nonsense mutation, p.Q41X, was observed. In three p.V281L mutation patients, the phenotype was more severe than predicted by genotype. Sequence analysis revealed an intronic alteration in the allele carrying the p.V281L mutation [IVS2 + 5G > A; p.V281L]. An aberrant splicing in this p.V281L mutated allele explains the clinical phenotype. CONCLUSIONS A high percentage of CYP21A2 affected alleles is detected by the 11-mutation screening study. Genotype-phenotype correlation was high, but when the phenotype is more severe than predicted by genotype, presence of two alterations in one allele should be ruled out.
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Affiliation(s)
- Roxana Marino
- Endocrinology Service, Hospital de Pediatria Garrahan, Buenos Aires, Argentina
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Campos VC, Pereira RMC, Torres N, Castro MD, Aguiar-Oliveira MH. High frequency of Q318X mutation in patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency in northeast Brazil. ACTA ACUST UNITED AC 2009; 53:40-6. [PMID: 19347184 DOI: 10.1590/s0004-27302009000100007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2008] [Accepted: 11/24/2008] [Indexed: 11/22/2022]
Abstract
OBJECTIVES Deficiency of 21-hydroxylase is the most common form of congenital adrenal hyperplasia (CAH-21OH). The aim of this study was to determine, by allele-specific PCR, the frequency of microconversions of the CYP21A2, in sixteen patients with the classical forms and in 5 patients with the nonclassical (NC) form of CAH-21OH and correlate genotype with phenotype. METHODS Genotypes were classified into 3 mutation groups (A, B and C), based on the degree of enzymatic activity. Screening for 7 microconversions by allele-specific PCR diagnosed 74.3% (n=26) of the 35 unrelated alleles. RESULTS The most frequent mutations were Q318X (25.7%), V281L (17.1%), I2 Splice (14.3%), I172N (14.3%), and R356W (14.3%). Genotype was identified in 57.1% of the patients. We observed correlation between genotype and phenotype in 91.7% of the cases. CONCLUSION The highest frequency for Q318X (25.7%) when compared to other studies may reflect individual sample variations in this Northeastern population.
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Affiliation(s)
- Viviane C Campos
- Division of Endocrinology, Federal University of Sergipe, Aracaju, SE, Brazil.
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Abstract
Congenital adrenal hyperplasia (CAH) is one of the most common inherited metabolic disorders. It comprises a group of autosomal recessive disorders caused by the deficiency of one of four steroidogenic enzymes involved in cortisol biosynthesis or in the electron donor enzyme P450 oxidoreductase (POR) that serves as electron donor to steroidogenic cytochrome P450 (CYP) type II enzymes. The biochemical and clinical phenotype depends on the specific enzymatic defect and the impairment of specific enzyme activity. Defects of steroid 21-hydroxylase (CYP21A2) and 11beta-hydroxylase (CYP11B1) only affect adrenal steroidogenesis, whereas 17alpha-hydroxylase (CYP17A1) and 3beta-hydroxysteroid dehydrogenase type 2 (HSD3B2) deficiency also impact on gonadal steroid biosynthesis. Inactivating POR gene mutations are the cause of CAH manifesting with apparent combined CYP17A1-CYP21A2 deficiency. P450 oxidoreductase deficiency (ORD) has a complex phenotype including two unique features not observed in any other CAH variant: skeletal malformations and severe genital ambiguity in both sexes.
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Affiliation(s)
- Nils Krone
- Centre for Endocrinology, Diabetes & Metabolism, School of Clinical & Experimental Medicine, Institute of Biomedical Research, Edgbaston, Birmingham, UK.
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Baş F, Kayserili H, Darendeliler F, Uyguner O, Günöz H, Yüksel Apak M, Atalar F, Bundak R, Wilson RC, New MI, Wollnik B, Saka N. CYP21A2 gene mutations in congenital adrenal hyperplasia: genotype-phenotype correlation in Turkish children. J Clin Res Pediatr Endocrinol 2009; 1:116-28. [PMID: 21274396 PMCID: PMC3005650 DOI: 10.4008/jcrpe.v1i3.49] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2009] [Accepted: 02/23/2009] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND Congenital adrenal hyperplasia (CAH) due 21-hydroxylase deficiency (21-OHD) is a common autosomal recessive disorder. It is caused by defects in the CYP21A2 gene. OBJECTIVE Our aim was to determine the frequency of common gene mutations and to evaluate genotype-phenotype correlations in Turkish 21-OHD patients. METHODS Molecular analysis of the CYP21A2 gene was performed for the detection of the eight most common point mutations [p.P30L, IVS2-13C>G (IVS-2), p.I172N, exon 6 mutation cluster (p.I236N, p.V237E, p.M239K), p.V281L, p.Q318X, p.R356W, 8-bp-deletion], of large deletion and conversion by southern blotting, allele specific semi-quantitative PCR/enzyme restriction method and sequencing, in 56 patients with 21-OHD, from 52 families. RESULTS Disease-causing mutations were identified in 77 out of 91 alleles (84.6%) of the patients. Mutations were found in 34 of 43 alleles (79.1%) in salt wasting (SW; n=26), 32 of 36 alleles (88.8%) in simple virilizing (SV; n=24) and 11 of 12 alleles (91.6%) in non-classical (NC; n=6) form of CAH. The most frequent mutations were IVS-2 (22.0%), large conversion (14.3%), p.I172N (9.9%) p.R356W (8.8%), and large deletion (6.6%). In the SW form, the most frequent genotypes were homozygous for IVS-2 (11.5%) and homozygous for large conversion of the gene (11.5%). In the SV form, the most frequent genotype was homozygous for IVS-2 (20%), followed by compound heterozygous for p.I172N/8-bp del (10%). Homozygous for p.V281L (16.7%) was most common in NC. In most cases there was good correlation between genotype and phenotype. In the SW and NC forms, genotypes of all the patients correlated with their phenotypes. CONCLUSIONS This is the first comprehensive study on the molecular basis of CAH patients in the Turkish population. Based on these results, we propose a modified screening strategy to facilitate molecular testing of CAH patients in our population.
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Affiliation(s)
- Firdevs Baş
- Istanbul University, Istanbul Faculty of Medicine, Department of Pediatrics, Pediatric Endocrinology Unit, Istanbul, Turkey.
| | - Hülya Kayserili
- Istanbul University, Istanbul Faculty of Medicine, Medical Genetics Department, Istanbul, Turkey
| | - Feyza Darendeliler
- Istanbul University, Istanbul Faculty of Medicine, Department of Pediatrics, Pediatric Endocrinology Unit, Istanbul, Turkey
| | - Oya Uyguner
- Istanbul University, Istanbul Faculty of Medicine, Medical Genetics Department, Istanbul, Turkey
| | - Hülya Günöz
- Istanbul University, Istanbul Faculty of Medicine, Department of Pediatrics, Pediatric Endocrinology Unit, Istanbul, Turkey
| | - Memnune Yüksel Apak
- Istanbul University, Istanbul Faculty of Medicine, Medical Genetics Department, Istanbul, Turkey
| | - Fatmahan Atalar
- Istanbul University, Istanbul Faculty of Medicine, Medical Genetics Department, Istanbul, Turkey
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Istanbul University, Institute for Experimental Medicine, DETAE, Istanbul, Turkey
| | - Rüveyde Bundak
- Istanbul University, Istanbul Faculty of Medicine, Department of Pediatrics, Pediatric Endocrinology Unit, Istanbul, Turkey
| | - Robert C. Wilson
- Mount Sinai School of Medicine, Department of Pediatrics, New York, NY, USA
| | - Maria I. New
- Mount Sinai School of Medicine, Department of Pediatrics, New York, NY, USA
| | - Bernd Wollnik
- Center for Molecular Medicine Cologne, and Institute of Human Genetics, University of Cologne, Cologne, Germany
| | - Nurçin Saka
- Istanbul University, Istanbul Faculty of Medicine, Department of Pediatrics, Pediatric Endocrinology Unit, Istanbul, Turkey
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Mutation distribution and CYP21/C4 locus variability in Brazilian families with the classical form of the 21-hydroxylase deficiency. Acta Paediatr 2007. [DOI: 10.1111/j.1651-2227.1999.tb01096.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Vakili R, Baradaran-Heravi A, Barid-Fatehi B, Gholamin M, Ghaemi N, Abbaszadegan MR. Molecular analysis of the CYP21 gene and prenatal diagnosis in families with 21-hydroxylase deficiency in northeastern Iran. HORMONE RESEARCH 2005; 63:119-24. [PMID: 15775714 DOI: 10.1159/000084570] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2004] [Accepted: 02/01/2005] [Indexed: 11/19/2022]
Abstract
OBJECTIVES A rapid and convenient approach for the detection of the most common CYP21 gene mutations in patients with congenital adrenal hyperplasia (CAH) with classical forms of 21-hydroxylase deficiency was used. In addition, a new semiquantitative strategy for the detection of del8-bp was designed. These procedures were used for prenatal diagnosis and genotype-phenotype correlation in northeastern Iran. DESIGN Molecular analysis of the CYP21 gene for the detection of the 9 most common mutations (CYP21gene deletion, P30L, i2g, del-8bp, I172N, E6 cluster, V281L, Q318X and R356W) was performed on 30 CAH patients and for prenatal diagnosis in 2 cases. METHODS Restriction fragment length polymorphism, amplification-created restriction sites, allele-specific polymerase chain reaction (PCR) and semiquantitative PCR were performed. RESULTS We characterized 90% of the CAH chromosomes. The most frequent mutations in the CYP21 gene were del-CYP21 (25%), I172N (22%) and i2g (15%). Unlike in other ethnic groups, there was no R356W mutation, however, a higher rate of del-8bp (10%) was found in our population. Wealso found 6 complex alleles in our patients. For 2 families prenatal CYP21 gene analysis resulted in the diagnosis of healthy fetuses and termination of dexamethasone treatment in the 15th week of gestation. Genotype-phenotype correlation was observed. The rate of homozygosity (50%) was greater than the predicted values due to the higher rate of parental consanguinity in our population. CONCLUSIONS These molecular procedures proved to be sensitive and rapid for the detection of the most common mutations of the CYP21 gene and prenatal diagnosis. Increased 17-hydroxyprogesterone, found in neonatal CAH screening, can be confirmed by these mutation analyses.
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Affiliation(s)
- Rahim Vakili
- Division of Endocrinology and Metabolism, Department of Pediatrics, Imam Reza Hospital, Mashhad University of Medical Sciences, Iran
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Cukier P, Bachega TASS, Mendonça BB, Billerbeck AEC. Use of nonradioactive labeling to detect large gene rearrangements in 21-hydroxylase deficiency. ACTA ACUST UNITED AC 2005; 59:369-74. [PMID: 15654491 DOI: 10.1590/s0041-87812004000600010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
PURPOSE To establish the Southern blotting technique using hybridization with a nonradioactive probe to detect large rearrangements of CYP21A2 in a Brazilian cohort with congenital adrenal hyperplasia due to 21-hydroxylase deficiency (CAH-21OH). METHOD We studied 42 patients, 2 of them related, comprising 80 non-related alleles. DNA samples were obtained from peripheral blood, digested by restriction enzyme Taq I, submitted to Southern blotting and hybridized with biotin-labeled probes. RESULTS This method was shown to be reliable with results similar to the radioactive-labeling method. We found CYP21A2 deletion (2.5%), large gene conversion (8.8%), CYP21AP deletion (3.8%), and CYP21A1P duplication (6.3%). These frequencies were similar to those found in our previous study in which a large number of cases were studied. Good hybridization patterns were achieved with a smaller amount of DNA (5 mug), and fragment signs were observed after 5 minutes to 1 hour of exposure. CONCLUSIONS We established a non-radioactive (biotin) Southern blot/hybridization methodology for CYP21A2 large rearrangements with good results. Despite being more arduous, this technique is faster, requires a smaller amount of DNA, and most importantly, avoids problems with the use of radioactivity.
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Affiliation(s)
- Priscilla Cukier
- Discipline od Endocrinology, Hospital das Clínicas, Faculty of Medicine, University of São Paulo, São Paulo, SP, Brazil
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Bachega TASS, Billerbeck AEC, Parente EB, Lemos-Marini SHV, Baptista MTM, Mello MP, Guerra G, Kuperman H, Setian N, Damiani D, Torres N, Castro MD, Mendonça BBD. Estudo multicêntrico de pacientes brasileiros com deficiência da 21-hidroxilase: correlação do genótipo com o fenótipo. ACTA ACUST UNITED AC 2004; 48:697-704. [PMID: 15761541 DOI: 10.1590/s0004-27302004000500016] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Analisamos as características clínicas e moleculares de 205 pacientes portadores das diferentes formas clínicas da deficiência da 21-hidroxilase, com diagnóstico hormonal e molecular definidos. As mutações mais freqüentes foram a I2 splice na forma perdedora de sal, a I172N na forma virilizante simples e a V281L na forma não clássica, com freqüências semelhantes às de outros estudos. Obtivemos baixa freqüência de deleção do gene da 21-hidroxilase, de forma semelhante ao identificado nas populações argentina e mexicana. Cinco mutações novas foram descritas em nossa população: G424S, H28+C, Ins 1003^1004 A, R408C e IVS2-2A>G. A severidade do genótipo também se correlacionou diretamente com níveis mais elevados de 17OH-progesterona e de testosterona. As mutações foram classificadas em três grupos, de acordo com o comprometimento da atividade enzimática observado in vitro: Grupo A: atividade de 0-2%; Grupo B: atividade de 3-7% e Grupo C: atividade >20%. Houve forte correlação do grupo A com a forma perdedora de sal, do grupo B com a forma virilizante simples e do grupo C com a forma não clássica. A mutação I2 splice (Grupo A) em homo ou hemizigose conferiu o fenótipo de forma clássica, embora tanto a forma perdedora de sal quanto a forma virilizante simples tenham sido identificadas. A boa correlação do genótipo com o fenótipo na HAC-21OH permite sua aplicação na prática clínica, para o aconselhamento genético, diagnóstico e tratamento pré-natal das gestações de risco para a forma clássica da HAC-21OH e para confirmação diagnóstica após screening neonatal da HAC-21OH, exceto na presença da mutação I2splice.
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Affiliation(s)
- Tânia A S S Bachega
- Departamento de Clínica Médica, Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo.
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Torres N, Mello MP, Germano CMR, Elias LLK, Moreira AC, Castro M. Phenotype and genotype correlation of the microconversion from the CYP21A1P to the CYP21A2 gene in congenital adrenal hyperplasia. Braz J Med Biol Res 2003; 36:1311-8. [PMID: 14502362 DOI: 10.1590/s0100-879x2003001000006] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Deficiency of 21-hydroxylase is the most common form of congenital adrenal hyperplasia (CAH-21OH). We determined by allele-specific PCR the frequency of microconversion in the CYP21A2 gene in 50 Brazilian patients with the classical (salt wasting: SW and simple virilizing: SV) forms and nonclassical (NC) form of CAH-21OH and correlated genotype with phenotype. Genotypes were classified into three mutation groups (A, B, and C) based on the amount of enzymatic activity in in vitro studies using adrenal cells. In 94 unrelated alleles, we diagnosed 76% of the affected alleles after screening for 7 microconversions. The most frequent point mutations observed in this series were I172N (19%), V281L (18%), and IVS2,A/C>G,-12 (15%). In the SW form, the most frequent mutation was IVS2,A/C>G,-12 (38%), in the SV form it was I172N (53%), and in the NC form it was V281L (57.7%). We observed a good correlation between genotype and phenotype. Discordance between genotype and phenotype was found in one SV patient with a mild mutation in one of the alleles (R356W/V281L). However, we cannot rule out the presence of an additional mutation in these alleles. We also observed a good correlation of genotype with 17alpha-hydroxyprogesterone, testosterone, and androstenedione levels. The severity of external genitalia virilization correlated with the severity of mutation. In conclusion, the frequencies described in the present study did not differ from worldwide studies, including the Brazilian population. The few differences observed may reflect individual sample variations. This new Brazilian cohort study suggests the presence of new mutations in Brazilian patients with different forms of CAH-21OH.
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Affiliation(s)
- N Torres
- Departamento de Patologia Clínica, Faculdade de Ciências M dicas, Universidade Estadual de Campinas, Campinas, SP, Brasil
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Belgorosky A, Marino R, Rivarola M. Molecular analysis of the 21-hydroxylase gene. Clin Endocrinol (Oxf) 2003; 58:247. [PMID: 12580943 DOI: 10.1046/j.1365-2265.2003.17092.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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15
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Billerbeck AEC, Mendonca BB, Pinto EM, Madureira G, Arnhold IJP, Bachega TASS. Three novel mutations in CYP21 gene in Brazilian patients with the classical form of 21-hydroxylase deficiency due to a founder effect. J Clin Endocrinol Metab 2002; 87:4314-7. [PMID: 12213891 DOI: 10.1210/jc.2001-011939] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Three different new mutations were found after CYP21 gene sequencing in three unrelated patients with the classical form of the 21-hydroxylase deficiency. These mutations were also screened in their affected relatives. In one patient and her brother, both affected with the simple virilizing form and in their aunt, with the nonclassical form, an AG>GG transition was found in the acceptor site of intron 2. In another patient with the salt wasting form, we found a 1003 1004 insA, in exon 4, that altered the reading frame and created a stop codon in codon 297. In the third patient and his sister, we found a C>T transition in codon 408. This transition led to the substitution of arginine by cysteine (R408C) in a conserved region where arginine is conserved in at least four different species. These siblings with the R408C mutation, both affected with the salt wasting form, have the IVS2-13A/C>G mutation in the other allele, suggesting that the R408C should lead to complete impairment of enzymatic activity. To rule out the possibility of polymorphism, R408C was screened through allele specific PCR, and it was not found in 100 normal alleles. The screening of these three new mutations by allele-specific PCR or enzymatic restriction in 212 CAH patients disclosed their presence in 2.3% (9/387) of the alleles. All three new mutations were found in compound heterozygous state with previously known mutations. Microsatellite studies, using markers flanking CYP21 gene, revealed that each new mutation presents the same haplotype, suggesting a gene founder effect, similar to what was previously observed with the G424S mutation also described in our population. Although microconversion events are the main cause of mutations in the CYP21 gene, random mutations with a common origin can also be the cause of 21-hydroxylase deficiency.
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Affiliation(s)
- Ana Elisa C Billerbeck
- Unidade de Endocrinologia do Desenvolvimento e Laboratório de Hormônios e Genética Molecular, Disciplina de Endocrinologia, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, Brazil.
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Ezquieta B, Cueva E, Oyarzábal M, Oliver A, Varela JM, Jariego C. Gene conversion (655G splicing mutation) and the founder effect (Gln318Stop) contribute to the most frequent severe point mutations in congenital adrenal hyperplasia (21-hydroxylase deficiency) in the Spanish population. Clin Genet 2002; 62:181-8. [PMID: 12220458 DOI: 10.1034/j.1399-0004.2002.620213.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
This study addresses the contributions of gene conversion and a founder effect to the distribution of the two most frequent severe point mutations of the 21-hydroxylase (21OH) gene causing congenital adrenal hyperplasia: the 655G splicing mutation at intron 2, and Gln318Stop in a Spanish population. Direct and indirect analyses of segregated mutant and normal 21OH genes in 200 Spanish families (classic and nonclassic 21OH deficiency) were performed. Both mechanisms were found to contribute to different degrees to the defective investigated alleles. The 655G splicing mutation (62 alleles, 15.5%) seemed to be almost exclusively related to recent conversion events, whereas Gln318Stop (33 alleles, 8.3%) is more likely to be due to the dissemination of remotely generated mutant alleles. Other severe defective alleles, 8 bp-deletion (13 alleles, 3.3%), 306insT (5 alleles, 1.3%), and gene deletions (43 alleles, 11%), as well as the mild mutation Val281Leu (120 alleles, 30%), also appear to be strongly associated with particular D6S273 alleles. Although gene conversion contributes to the generation of severe 21OH alleles, the high frequency of some severe mutations in different geographic areas is consistent with a founder effect.
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Affiliation(s)
- B Ezquieta
- Servicio Bioquímica, Hospital La Paz, Madrid, Spain.
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17
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Dain LB, Buzzalino ND, Oneto A, Belli S, Stivel M, Pasqualini T, Minutolo C, Charreau EH, Alba LG. Classical and nonclassical 21-hydroxylase deficiency: a molecular study of Argentine patients. Clin Endocrinol (Oxf) 2002; 56:239-45. [PMID: 11874416 DOI: 10.1046/j.0300-0664.2001.01419.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To characterize the molecular basis of the 21-hydroxylase deficiency in a group of Argentine patients presenting the classical and nonclassical forms of the disease. DESIGN To analyse the frequency of point mutations in the CYP21 gene by DNA amplification and mutation detection. PATIENTS Forty-one patients from 36 nonrelated families: 25 nonclassical (NC), 11 salt-wasting (SW) and five simple virilizing (SV). A total of 27 parents and 13 nonaffected siblings were also analysed. MEASUREMENTS Basal steroid hormones and 17-hydroxyprogesterone levels following adrenal stimulation with adrenocorticotrophic hormone were measured, together with an analysis of 10 point mutations in the CYP21 gene. RESULTS A total of 83% and 74.4% classical and nonclassical chromosomes, respectively, were characterized. The intron 2 mutation was the most prevalent among classical alleles. In addition, a high frequency for R356W was observed in both groups (13.3 and 6.9%, respectively), while V281L was the most frequent mutation among the nonclassical patients with a frequency of 39.5%. No alleles containing P30L were observed, and one de novo mutation (R356W) was found. A total of 68.3% patients were fully genotyped, and all but one showed no genotype/phenotype discrepancy. Though the cut-off value for post-ACTH 17-hydroxyprogesterone stimulation was 30.25 nmol/l (10.00 microg/l), the lowest value observed in the fully genotyped nonclassical group was 42.35 nmol/l (14.00 microg/l). CONCLUSIONS The high number of unidentified alleles in the nonclassical group suggests that less frequent mutations, or the presence of new ones, might be the cause of the disease in the Argentine population. Alternatively, the cut-off value in the ACTH-stimulated 17-hydroxyprogesterone test might overestimate the diagnosis of the nonclassical form by including some patients with heterozygous status.
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Affiliation(s)
- Liliana B Dain
- Centro Nacional de Genética Médica, División de Endocrinología Hospital Durand, Servicio de Pediatría Hospital Italiano.
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18
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Abstract
Congenital adrenal hyperplasia (CAH) is a common autosomal recessive disorder caused mainly by defects in the steroid 21-hydroxylase (CYP21) gene. More than 90% of CAH cases are caused by mutations of the CYP21 gene on chromosome 6p21.3. The wide range of CAH phenotypes is associated with multiple mutations known to affect 21-hydroxylase enzyme activity. To date, 56 different CYP21 mutations have been reported, mostly point mutations, but small deletions or insertions have been described too, as well as complete gene deletions. Fifteen mutations, constituting 90-95% of alleles, are derived from intergenic recombination of DNA sequences between the CYP21 gene and the highly homologous CYP21P pseudogene, while the remaining are spontaneous mutations. A reliable and accurate detection of CYP21 mutations is not only important for clinical diagnosis, but also for carrier detection as there is a high variability in the basal level of 17-hydroxyprogesterone between normal and heterozygous individuals. Several strategies based on polymerase chain reaction (PCR)-driven amplification with allele-specific oligonucleotides to the CYP21 gene have been developed. It has been demonstrated that one reaction for PCR amplification of the CYP21 gene and the chimeric CYP21P/CYP21 gene using mixed primers in combination with nested PCR and single-strand conformation polymorphism is considered highly efficient and accurate for molecular diagnosis of CAH due to 21-hydroxylase deficiency.
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Affiliation(s)
- H H Lee
- Kingcar Food Industrial Co, Ltd, Yuan-Shan Research Institute, Taiwan, Republic of China.
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19
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Mathur R, Menon PS, Kabra M, Goyal RK, Verma IC. Molecular characterization of mutations in Indian children with congenital adrenal hyperplasia due to steroid 21-hydroxylase deficiency. J Pediatr Endocrinol Metab 2001; 14:27-35. [PMID: 11220701 DOI: 10.1515/jpem.2001.14.1.27] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Congenital adrenal hyperplasia (CAH) is the commonest cause of female pseudohermaphroditism. It is most often due to steroid 21-hydroxylase deficiency resulting from mutations in the CYP21 gene. This study was conducted to characterize mutations in the CYP21 gene, determine their frequency and correlate genotype with phenotype in Indian children with CAH. Twenty-eight patients with salt-wasting (SW) or simple-virilizing (SV) forms of the disease as well as parents and siblings were studied. Allele specific PCR was carried out and rapid characterization of six mutations was achieved in 23 patients. Twelve patients were homozygous for the mutations and 11 were heterozygous, of whom eight were compound heterozygotes and three were hemizygotes; no mutation was found in five patients. The homozygosity of the mutations was found to be high in our population. The most common mutation was Ile173Asn (31.8%), followed by intron2 splice (27.2%), Gln319stop (22.7%), gene deletion (15.9%) and Pro31Leu (2.2%). Genotype-phenotype correlations showed that the most frequent mutations in the SW group were intron2 splice and Gln319stop mutations (33.3% each) and Ile173Asn (71.4%) in the SV group.
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Affiliation(s)
- R Mathur
- Department of Pediatrics, All India Institute of Medical Sciences, Ansari Nagar, New Delhi.
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20
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Bachega TA, Billerbeck AE, Madureira G, Marcondes JA, Longui CA, Leite MV, Arnhold IJ, Mendonça BB. 21-Hydroxylase deficiency in Brazil. Braz J Med Biol Res 2000; 33:1211-6. [PMID: 11004722 DOI: 10.1590/s0100-879x2000001000011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
We determined the frequency of large rearrangements and point mutations in 130 Brazilian patients with 21-hydroxylase deficiency and correlated genotype with phenotype. The frequency of CYP21 deletions was lower (4.4%) than in most of the previous series described, whereas the frequency of large gene conversions was similar to the frequency reported in the literature (6.6%). The most frequent point mutations were I2 splice (41.8% in salt wasting - SW), I172N (32.6% in simple virilizing - SV) and V281L (40.2% in the late onset form - LO). The frequency of the nine most common point mutations was similar to that reported for other countries. The 93 fully genotyped patients were classified into 3 mutation groups based on the degree of enzymatic activity (A<2%, B approximately 2%, C>20%). In group A, 62% of cases presented the SW form; in group B, 96% the SV form, and in group C, 88% the LO form. We diagnosed 80% of the affected alleles after screening for large rearrangements and 15 point mutations. To diagnose these remaining alleles we sequenced the CYP21 gene of one patient with the SV form and identified a heterozygous G-->A transition in codon 424. This mutation leads to a substitution of glycine by serine in a conserved region and was also found in a compound heterozygous state in 4 other patients. The mutation G424S presented a linkage disequilibrium with CYP21P and C4A gene deletions and HLA DR17, suggesting a probable founder effect. Search for the G424S mutation in other populations will reveal if it is restricted to the Brazilian patients or if it has a wider ethnic distribution.
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Affiliation(s)
- T A Bachega
- Unidade de Endocrinologia do Desenvolvimento e Laboratório de Hormônios e Genética Molecular, Disciplina de Endocrinologia, Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brasil
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21
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Fardella CE, Poggi H, Soto J, Torrealba I, Cattani A, Ugarte F, Cortinez A, Foradori A. Mutations in the CYP21 B gene in a Chilean population with simple virilizing congenital adrenal hyperplasia. J Endocrinol Invest 2000; 23:412-6. [PMID: 10908170 DOI: 10.1007/bf03343746] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Steroid 21-hydroxylase deficiency (21OHD) compromises about 95% of all cases of congenital adrenal hyperplasia. We have characterized the disease-causing mutations in the steroid 21-hydroxylase genes of 19 Chilean patients (12 females and 7 males) with the simple virilizing (SV) form of 21OHD and compared them with other SV-populations. Using allele-specific polymerase chain reaction, we identified lesions in 28 chromosomes out of 38 tested (73.7%). The most frequent finding was the mutation I173N=12/38 (31.6%) similar as described in Caucasian, Asian and other Hispanic populations, where this mutation represents around 20-40% of the genetic defects in the CYP21B gene. The mutation V282L=4/38 (10.5%) and deletion (Del) or large gene conversion (LGC)=3/38 (7.9%) were also frequently detected. Only 2 alleles carried the mutation I2 splice (5.3%), this frequency is lower than that reported in Caucasian or in Mexican populations. We did not find alleles with the mutations R357W, Cluster E6, P31L and P454S in these patients. The complete genotype was determined in 11/19 patients (58%) and one allele in 6/19 patients (31.6%). In summary, about 30% of the Chilean population with SV 21OHD presented the missense mutation I173N as described in other populations. The frequency of the other lesions showed differences even between populations with similar genetic background.
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Affiliation(s)
- C E Fardella
- Department of Endocrinology, Faculty of Medicine, Catholic University of Chile, Santiago
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22
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Abstract
More than 90% of cases of congenital adrenal hyperplasia (CAH, the inherited inability to synthesize cortisol) are caused by 21-hydroxylase deficiency. Females with severe, classic 21-hydroxylase deficiency are exposed to excess androgens prenatally and are born with virilized external genitalia. Most patients cannot synthesize sufficient aldosterone to maintain sodium balance and may develop potentially fatal "salt wasting" crises if not treated. The disease is caused by mutations in the CYP21 gene encoding the steroid 21-hydroxylase enzyme. More than 90% of these mutations result from intergenic recombinations between CYP21 and the closely linked CYP21P pseudogene. Approximately 20% are gene deletions due to unequal crossing over during meiosis, whereas the remainder are gene conversions--transfers to CYP21 of deleterious mutations normally present in CYP21P. The degree to which each mutation compromises enzymatic activity is strongly correlated with the clinical severity of the disease in patients carrying it. Prenatal diagnosis by direct mutation detection permits prenatal treatment of affected females to minimize genital virilization. Neonatal screening by hormonal methods identifies affected children before salt wasting crises develop, reducing mortality from this condition. Glucocorticoid and mineralocorticoid replacement are the mainstays of treatment, but more rational dosing and additional therapies are being developed.
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Affiliation(s)
- P C White
- Division of Pediatric Endocrinology, University of Texas Southwestern Medical Center, Dallas 75390-9063, USA.
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23
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Stratakis CA, Rennert OM. Congenital adrenal hyperplasia: molecular genetics and alternative approaches to treatment. Crit Rev Clin Lab Sci 1999; 36:329-63. [PMID: 10486704 DOI: 10.1080/10408369991239222] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Several autosomal recessive disorders affecting the adrenal cortex and its development and leading to defective cortisol biosynthesis are known under the collective term "congenital adrenal hyperplasia" (CAH). Over the last two decades, the genes causing most of these disorders have been identified and molecular genetics may supplement their clinical and biochemical diagnosis. In addition, new treatments have emerged; although gene therapy has yet to be applied in humans, studies are ongoing in gene transfer in adrenocortical cell lines and animal models. In this review, after a brief introduction on the developmental biology and biochemistry of the adrenal cortex and its enzymes, we will list the new developments in the genetics and treatment of diseases causing CAH, starting with the most recent findings. This order happens to follow adrenal steroidogenesis from the mitochondrial entry of cholesterol to cortisol synthesis; it is unlike other presentations of CAH syndromes that start with the most frequently seen syndromes, because the latter were also the first to be investigated at the genetic level and have been extensively reviewed elsewhere. We will start with the latest syndrome to be molecularly investigated, congenital lipoid adrenal hyperplasia (CLAH), which is caused by mutations in the gene coding for the steroidogenic acute regulatory (StAR) protein. We will then present new developments in the genetics of 3-beta-hydroxysteroid dehydrogenase (3 beta HSD), 17 hydroxylase and 17,20-lyase (P450c17), 11 hydroxylase (P450c11 beta), and 21 hydroxylase (P450c21) deficiencies. Alternative treatment approaches and gene therapy experiments are reviewed collectively in the last section, because they are still in their infantile stages.
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Affiliation(s)
- C A Stratakis
- Unit on Genetics and Endocrinology (UGEN), National Institute of Child Health and Human Development, National Institutes of Health (NIH), Bethesda, Maryland 20892-1862, USA
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24
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Ferenczi A, Garami M, Kiss E, Pék M, Sasvári-Székely M, Barta C, Staub M, Sólyom J, Fekete G. Screening for mutations of 21-hydroxylase gene in Hungarian patients with congenital adrenal hyperplasia. J Clin Endocrinol Metab 1999; 84:2369-72. [PMID: 10404805 DOI: 10.1210/jcem.84.7.5835] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
Congenital adrenal hyperplasia (CAH) is a group of autosomal recessive disorders, causing impaired secretion of cortisol and aldosterone from the adrenal cortex, with subsequent overproduction of adrenal androgens. The most common enzyme defect causing CAH is steroid 21-hydroxylase deficiency. To determine the mutational spectrum in the Hungarian CAH population, the CYP21 active gene was analyzed using PCR. A total of 297 Hungarian patients with 21-hydroxylase deficiency are registered in the 2nd Department of Pediatrics, Budapest, Hungary, and their clinical status was evaluated. Blood samples for CYP21 genotype determination could be obtained from 167 patients (representing 306 unrelated chromosomes and 56.2% of the total group of patients). Eight of the most common mutations were screened [In2 (intron 2 splice mutation), I172N, Del (Del: apparents large gene conversion), Q318X, R356W, 1761Tins, ClusterE6, V281L] using allele-specific amplification. The most frequent mutation in the Hungarian CAH population was found to be In2. Our results have shown a good genotype/phenotype correlation in case of most mutations; the In2 mutation is associated mostly with the severe form of the disease, whereas I172N was expressed in a wide spectrum of phenotypes. 1999)
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Affiliation(s)
- A Ferenczi
- 2nd Department of Pediatrics, Semmelweis University of Medicine, Budapest, Hungary.
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25
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26
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Fardella CE, Poggi H, Pineda P, Soto J, Torrealba I, Cattani A, Oestreicher E, Foradori A. Salt-wasting congenital adrenal hyperplasia: detection of mutations in CYP21B gene in a Chilean population. J Clin Endocrinol Metab 1998; 83:3357-60. [PMID: 9745454 DOI: 10.1210/jcem.83.9.5071] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The steroid 21-hydroxylase deficiency (21OHD) is the most frequent cause of congenital adrenal hyperplasia. We have characterized the disease-causing mutations in the 21-hydroxylase genes of 63 patients with salt-wasting congenital adrenal hyperplasia from a Chilean population of Hispanic origin, a group that has been scarcely evaluated. Using allele-specific PCR, lesions were identified in 97 chromosomes out of 126 tested (77%). The most frequent findings were the gene deletion or large gene conversion (LGC) = 22.9%, I2 splice = 19%, R357W = 12.7%, and Q319X = 10.5%. We did not find alleles with the mutation F308insT and we found three alleles with the cluster E6. The frequency of the point mutation R357W was at least two times more frequent than the one found in Caucasians populations, but similar to that communicated in Asian populations; this finding may be explained by the Asian ancestry of our South-Amerindian population. The frequency of Q319X was also high, similar only to those patients studied in Italy and in a neighboring Argentinian population. In summary, this is a genetic characterization of 21OHD made in an almost pure Hispanic population in Latin America. The high frequency of deletion of CYP21B gene, I2 splice, R357W, and Q319X mutations probably reflects the European-Caucasian-Spanish influence of the conquerors, mixed with Amerindians of Asian ancestry and modulated by other European immigrations.
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Affiliation(s)
- C E Fardella
- Department of Endocrinology, University of Chile, Santiago, Chile
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