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Pignatelli D, Carvalho BL, Palmeiro A, Barros A, Guerreiro SG, Macut D. The Complexities in Genotyping of Congenital Adrenal Hyperplasia: 21-Hydroxylase Deficiency. Front Endocrinol (Lausanne) 2019; 10:432. [PMID: 31333583 PMCID: PMC6620563 DOI: 10.3389/fendo.2019.00432] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Accepted: 06/17/2019] [Indexed: 12/13/2022] Open
Abstract
The deficiency of 21-hydroxylase due to CYP21A2 pathogenic variants is a rather frequent disease with serious consequences, going from a real mortality risk to infertility and to milder symptoms, nevertheless important for affecting the patients' self-esteem. In the most severe cases life-threatening adrenal salt wasting crises may occur. Significant morbidity including the possibility of mistaken gender determination, precocious puberty, infertility and growth arrest with consequent short stature may also affect these patients. In the less severe cases milder symptoms like hirsutism will likely affect the image of the self with strong psychological consequences. Its diagnosis is confirmed by 17OH-progesterone dosages exceeding the cut-off value of 10/15 ng/ml but genotyping is progressively assuming an essential role in the study of these patients particularly in confirming difficult cases, determining some aspects of the prognosis and allowing a correct genetic counseling. Genotyping is a difficult process due to the occurrence of both a gene and a highly homologous pseudo gene. However, new tools are opening new possibilities to this analysis and improving the chances of a correct diagnosis and better understanding of the underlying mechanisms of the disease. Beyond the 10 classic pathogenic variants usually searched for in most laboratories, a correct analysis of 21OH-deficiency cases implies completely sequencing of the entire gene and the determination of gene duplications. These are now recognized to occur frequently and can be responsible for some false positive cases. And finally, because gene conversions can include several pathogenic variants one cannot be certain of identifying that both alleles are affected without studying parental DNA samples. A complete genotype characterization should be considered essential in the preparation for pregnancy, even in the case of parents with milder forms of the disease, or even just carriers, since it has been reported that giving birth to progeny with the severe classic forms occurs with a much higher frequency than expected.
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Affiliation(s)
- Duarte Pignatelli
- Hospital S. João, Porto, Portugal
- Department of Biomedicine, Faculty of Medicine of Porto, Porto, Portugal
- IPATIMUP/I3S Research Institute, University of Porto, Porto, Portugal
- *Correspondence: Duarte Pignatelli
| | - Berta L. Carvalho
- Genetics, Department of Pathology, Faculty of Medicine, University of Porto, Porto, Portugal
- I3S Research Institute, University of Porto, Porto, Portugal
| | | | - Alberto Barros
- Genetics, Department of Pathology, Faculty of Medicine, University of Porto, Porto, Portugal
- I3S Research Institute, University of Porto, Porto, Portugal
| | - Susana G. Guerreiro
- Department of Biomedicine, Faculty of Medicine of Porto, Porto, Portugal
- IPATIMUP/I3S Research Institute, University of Porto, Porto, Portugal
| | - Djuro Macut
- Clinic of Endocrinology, Diabetes and Metabolic Diseases, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
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Moura-Massari VO, Cunha FS, Garcia Gomes L, Bugano Diniz Gomes D, Marcondes JAM, Madureira G, de Mendonca BB, Bachega TASS. The Presence of Clitoromegaly in the Nonclassical Form of 21-Hydroxylase Deficiency Could Be Partially Modulated by the CAG Polymorphic Tract of the Androgen Receptor Gene. PLoS One 2016; 11:e0148548. [PMID: 26848581 PMCID: PMC4744051 DOI: 10.1371/journal.pone.0148548] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Accepted: 01/19/2016] [Indexed: 11/25/2022] Open
Abstract
Background In the nonclassical form (NC), good correlation has been observed between genotypes and 17OH-progesterone (17-OHP) levels. However, this correlation was not identified with regard to the severity of hyperandrogenic manifestations, which could depend on interindividual variability in peripheral androgen sensitivity. Androgen action is modulated by the polymorphic CAG tract (nCAG) of the androgen receptor (AR) gene and by polymorphisms in 5α-reductase type 2 (SRD5A2) enzyme, both of which are involved in the severity of hyperandrogenic disorders. Objectives To analyze whether nCAG-AR and SRD5A2 polymorphisms influence the severity of the nonclassical phenotype. Patients NC patients (n = 114) diagnosed by stimulated-17OHP ≥10 ng/mL were divided into groups according to the beginning of hyperandrogenic manifestations (pediatric and adolescent/adult) and CYP21A2 genotypes (C/C: homozygosis for mild mutations; A/C: compound heterozygosis for severe/mild mutations). Methods CYP21A2 mutations were screened by allelic-specific PCR, MLPA and/or sequencing. HpaII-digested and HpaII-undigested DNA samples underwent GeneScan analysis to study nCAG, and the SRD5A2 polymorphisms were screened by RLFP. Results Mean nCAG did not differ among pediatric, adolescent/adult and asymptomatic subjects. In the C/C genotype, we observed a significantly lower frequency of longer CAG alleles in pediatric patients than in adolescent/adults (p = 0.01). In patients carrying the A/C genotype, the frequencies of shorter and longer CAG alleles did not differ between pediatric patients and adolescent/adults (p>0.05). Patients with clitoromegaly had significantly lower weighted CAG biallelic mean than those without it: 19.1±2.7 and 21.6±2.5, respectively (p = 0.007), independent of the CYP21A2 genotype's severity. The SRD5A2 polymorphisms were not associated with the variability of hyperandrogenic NC phenotypes. Conclusions In this series, we observed a modulatory effect of the CAG-AR tract on clinical manifestations of the NC form. Although the NC form is a monogenic disorder, our preliminary data suggested that the interindividual variability of the hyperandrogenic phenotype could arise from polygenic interactions.
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Affiliation(s)
- Vivian Oliveira Moura-Massari
- Unidade de Suprarrenal, Laboratório de Hormônios e Genética Molecular LIM 42, Disciplina de Endocrinologia, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, Sao Paulo, Brazil
| | - Flávia Siqueira Cunha
- Unidade de Suprarrenal, Laboratório de Hormônios e Genética Molecular LIM 42, Disciplina de Endocrinologia, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, Sao Paulo, Brazil
- * E-mail: (FSC); (TASSB)
| | - Larissa Garcia Gomes
- Unidade de Suprarrenal, Laboratório de Hormônios e Genética Molecular LIM 42, Disciplina de Endocrinologia, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, Sao Paulo, Brazil
| | - Diogo Bugano Diniz Gomes
- Departamento de Clínica Médica, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, Sao Paulo, Brazil
| | - José Antônio Miguel Marcondes
- Unidade de Suprarrenal, Laboratório de Hormônios e Genética Molecular LIM 42, Disciplina de Endocrinologia, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, Sao Paulo, Brazil
| | - Guiomar Madureira
- Unidade de Suprarrenal, Laboratório de Hormônios e Genética Molecular LIM 42, Disciplina de Endocrinologia, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, Sao Paulo, Brazil
| | - Berenice Bilharinho de Mendonca
- Unidade de Suprarrenal, Laboratório de Hormônios e Genética Molecular LIM 42, Disciplina de Endocrinologia, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, Sao Paulo, Brazil
| | - Tânia A. Sartori Sanchez Bachega
- Unidade de Suprarrenal, Laboratório de Hormônios e Genética Molecular LIM 42, Disciplina de Endocrinologia, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, Sao Paulo, Brazil
- * E-mail: (FSC); (TASSB)
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Pallan PS, Wang C, Lei L, Yoshimoto FK, Auchus RJ, Waterman MR, Guengerich FP, Egli M. Human Cytochrome P450 21A2, the Major Steroid 21-Hydroxylase: STRUCTURE OF THE ENZYME·PROGESTERONE SUBSTRATE COMPLEX AND RATE-LIMITING C-H BOND CLEAVAGE. J Biol Chem 2015; 290:13128-43. [PMID: 25855791 DOI: 10.1074/jbc.m115.646307] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Indexed: 11/06/2022] Open
Abstract
Cytochrome P450 (P450) 21A2 is the major steroid 21-hydroxylase, and deficiency of this enzyme is involved in ∼95% of cases of human congenital adrenal hyperplasia, a disorder of adrenal steroidogenesis. A structure of the bovine enzyme that we published previously (Zhao, B., Lei, L., Kagawa, N., Sundaramoorthy, M., Banerjee, S., Nagy, L. D., Guengerich, F. P., and Waterman, M. R. (2012) Three-dimensional structure of steroid 21-hydroxylase (cytochrome P450 21A2) with two substrates reveals locations of disease-associated variants. J. Biol. Chem. 287, 10613-10622), containing two molecules of the substrate 17α-hydroxyprogesterone, has been used as a template for understanding genetic deficiencies. We have now obtained a crystal structure of human P450 21A2 in complex with progesterone, a substrate in adrenal 21-hydroxylation. Substrate binding and release were fast for human P450 21A2 with both substrates, and pre-steady-state kinetics showed a partial burst but only with progesterone as substrate and not 17α-hydroxyprogesterone. High intermolecular non-competitive kinetic deuterium isotope effects on both kcat and kcat/Km, from 5 to 11, were observed with both substrates, indicative of rate-limiting C-H bond cleavage and suggesting that the juxtaposition of the C21 carbon in the active site is critical for efficient oxidation. The estimated rate of binding of the substrate progesterone (kon 2.4 × 10(7) M(-1) s(-1)) is only ∼2-fold greater than the catalytic efficiency (kcat/Km = 1.3 × 10(7) M(-1) s(-1)) with this substrate, suggesting that the rate of substrate binding may also be partially rate-limiting. The structure of the human P450 21A2-substrate complex provides direct insight into mechanistic effects of genetic variants.
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Affiliation(s)
- Pradeep S Pallan
- From the Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146 and
| | - Chunxue Wang
- From the Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146 and
| | - Li Lei
- From the Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146 and
| | - Francis K Yoshimoto
- From the Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146 and
| | - Richard J Auchus
- the Division of Metabolism, Endocrinology, and Diabetes, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Michael R Waterman
- From the Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146 and
| | - F Peter Guengerich
- From the Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146 and
| | - Martin Egli
- From the Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146 and
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Dubey S, Idicula-Thomas S, Anwaruddin M, Saravanan C, Varma RR, Maitra A. A novel 9-bp insertion detected in steroid 21-hydroxylase gene (CYP21A2): prediction of its structural and functional implications by computational methods. J Biomed Sci 2009; 16:3. [PMID: 19272182 PMCID: PMC2653521 DOI: 10.1186/1423-0127-16-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2008] [Accepted: 01/08/2009] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND Steroid 21-hydroxylase deficiency is the most common cause of congenital adrenal hyperplasia (CAH). Detection of underlying mutations in CYP21A2 gene encoding steroid 21-hydroxylase enzyme is helpful both for confirmation of diagnosis and management of CAH patients. Here we report a novel 9-bp insertion in CYP21A2 gene and its structural and functional consequences on P450c21 protein by molecular modeling and molecular dynamics simulations methods. METHODS A 30-day-old child was referred to our laboratory for molecular diagnosis of CAH. Sequencing of the entire CYP21A2 gene revealed a novel insertion (duplication) of 9-bp in exon 2 of one allele and a well-known mutation I172N in exon 4 of other allele. Molecular modeling and simulation studies were carried out to understand the plausible structural and functional implications caused by the novel mutation. RESULTS Insertion of the nine bases in exon 2 resulted in addition of three valine residues at codon 71 of the P450c21 protein. Molecular dynamics simulations revealed that the mutant exhibits a faster unfolding kinetics and an overall destabilization of the structure due to the triple valine insertion was also observed. CONCLUSION The novel 9-bp insertion in exon 2 of CYP21A2 genesignificantly lowers the structural stability of P450c21 thereby leading to the probable loss of its function.
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Affiliation(s)
- Sudhisha Dubey
- Department of Molecular Endocrinology, National Institute for Research in Reproductive Health, Indian Council of Medical Research, J M Street, Parel, Mumbai, Maharashtra, India
| | - Susan Idicula-Thomas
- Biomedical Informatics Centre of Indian Council of Medical Research, National Institute for Research in Reproductive Health, J M Street, Parel, Mumbai, Maharashtra, India
| | - Mohammad Anwaruddin
- Biomedical Informatics Centre of Indian Council of Medical Research, National Institute for Research in Reproductive Health, J M Street, Parel, Mumbai, Maharashtra, India
| | - Chinnaraj Saravanan
- Department of Molecular Endocrinology, National Institute for Research in Reproductive Health, Indian Council of Medical Research, J M Street, Parel, Mumbai, Maharashtra, India
| | - R Raveendra Varma
- Department of Pediatrics and Neonatology, Mother's Hospital Trissur, Kerala, India
| | - Anurupa Maitra
- Department of Molecular Endocrinology, National Institute for Research in Reproductive Health, Indian Council of Medical Research, J M Street, Parel, Mumbai, Maharashtra, India
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Robins T, Bellanne-Chantelot C, Barbaro M, Cabrol S, Wedell A, Lajic S. Characterization of novel missense mutations in CYP21 causing congenital adrenal hyperplasia. J Mol Med (Berl) 2006; 85:247-55. [PMID: 17119906 DOI: 10.1007/s00109-006-0121-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2006] [Revised: 07/30/2006] [Accepted: 08/31/2006] [Indexed: 11/27/2022]
Abstract
Congenital adrenal hyperplasia due to 21-hydroxylase deficiency is the most common inherited disorder of steroid metabolism, with an incidence of 1/10,000 in the general Caucasian population. Although most patients carry a deletion of the CYP21 gene or any of nine pseudogene-derived point mutations, the number of reported rare mutations continues to increase, and consist today of more than 80 different point mutations. In this study, we report the characterization of four additional missense mutations in CYP21. Two of these, L166P and A391T, are novel missense mutations, whereas the R479L and R483Q mutations have been detected previously. Functional assays of mutagenized CYP21 were performed in transiently transfected mammalian cells in vitro, and enzymatic ability of substrate conversion of the two natural substrates of CYP21-17-hydroxyprogesterone and progesterone-was determined. All mutants displayed reduced in vitro enzyme activities compared with wild type, but to different extents, corresponding to clinical phenotypes that span the whole spectrum of disease severity. Functional studies are important to further establish the relationships between genotype and clinical phenotype as well as in vitro CYP21 activity in congenital adrenal hyperplasia due to 21-hydroxylase deficiency. This has relevance for diagnosis, prognosis, and genetic counseling for affected families.
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Affiliation(s)
- Tiina Robins
- Department of Molecular Medicine and Surgery, Center for Molecular Medicine (CMM) L8:02, Karolinska Institutet/Karolinska University Hospital, 17176, Stockholm, Sweden.
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