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Concolino P. Challenging Molecular Diagnosis of Congenital Adrenal Hyperplasia (CAH) Due to 21-Hydroxylase Deficiency: Case Series and Novel Variants of CYP21A2 Gene. Curr Issues Mol Biol 2024; 46:4832-4844. [PMID: 38785559 PMCID: PMC11119849 DOI: 10.3390/cimb46050291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2024] [Revised: 05/07/2024] [Accepted: 05/10/2024] [Indexed: 05/25/2024] Open
Abstract
Congenital adrenal hyperplasia (CAH) is a group of autosomal recessive genetic defects in cortisol synthesis and shows elevated ACTH concentrations, which in turn has downstream effects. The most common variant of CAH, 21-hydroxylase deficiency (21OHD), is the result of pathogenic variants in the CYP21A2 gene and is one of the most common monogenic disorders. However, the genetics of 21OHD is complex and challenging. The CYP21A2 gene is located in the RCCX copy number variation (CNV), a complex, multiallelic, and tandem CNV in the major histocompatibility complex (MHC) class III region on chromosome 6 (band 6p21.3). Here, CYP21A2 and its pseudogene CYP21A1P are located 30 kb apart and share a high nucleotide homology of approximately 98% and 96% in exons and introns, respectively. This high-sequence homology facilitates large structural rearrangements, copy number changes, and gene conversion through intergenic recombination. There is a good genotype-phenotype correlation in 21OHD, and genotyping can be performed to confirm the clinical diagnosis, predict long-term outcomes, and determine genetic counseling. Thus, genotyping in CAH is clinically relevant but the interpretations can be challenging for non-initiated clinicians. Here, there are some concrete examples of how molecular diagnosis can sometimes require the use of multiple molecular strategies.
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Affiliation(s)
- Paola Concolino
- Dipartimento di Scienze di Laboratorio ed Ematologiche, UOC Chimica, Biochimica e Biologia Molecolare Clinica, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Largo A. Gemelli 8, 00168 Rome, Italy
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Zhang X, Gao Y, Lu L, Cao Y, Zhang W, Sun B, Wu X, Tong A, Chen S, Wang X, Mao J, Nie M. Targeted long-read sequencing for comprehensive detection of CYP21A2 mutations in patients with 21-hydroxylase deficiency. J Endocrinol Invest 2024; 47:833-841. [PMID: 37815751 DOI: 10.1007/s40618-023-02197-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Accepted: 09/08/2023] [Indexed: 10/11/2023]
Abstract
BACKGROUND 21-Hydroxylase deficiency (21-OHD) is caused by pathogenic CYP21A2 variations. CYP21A2 is arranged in tandem with its highly homologous pseudogene CYP21A1P; therefore, it is prone to mismatch and rearrangement, producing different types of complex variations. There were few reports on using only one method to detect different CYP21A2 variants simultaneously. AIMS Targeted long-read sequencing method was used to detect all types of CYP21A2 variants in a series of patients with 21-OHD. METHODS A total of 59 patients with 21-OHD were enrolled from Peking Union Medical College Hospital. Long-range locus-specific PCR and long-read sequencing (LRS) were performed to detect the pathogenic variants in CYP21A2. RESULTS Copy-number variants of CYP21A2 were found in 25.4% of patients, including 5.1% with 3 copies of CYP21A2, 16.9% with 1 copy of CYP21A2, and 3.4% with 0 copy of CYP21A2. The remaining 74.6% of patients had 2 copies of CYP21A2. Pathogenic variants were identified in all 121 alleles of 59 patients. Specifically, single-nucleotide variants and small insertions/deletions (< 50 bp) were detected in 79 alleles, of which conversed from CYP21A1P were detected in 63 alleles, and rare variants were found in the other 16 alleles. Large gene conversions (> 50 bp) from pseudogene were detected in 10 alleles, and different chimeric genes (CYP21A1P/CYP21A2 or TNXA/TNXB) formed by large deletions were detected in 32 alleles. Of all variants, p.I173N was the most common variant (19.0%). CONCLUSIONS Our study demonstrated that targeted long-read sequencing is a comprehensive method for detecting CYP21A2 variations, which is helpful for genetic diagnosis in 21-OHD patients.
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Affiliation(s)
- X Zhang
- Department of Endocrinology, Key Laboratory of Endocrinology, National Health Commission (NHC), Peking Union Medical College Hospital), Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China
| | - Y Gao
- Department of Endocrinology, Key Laboratory of Endocrinology, National Health Commission (NHC), Peking Union Medical College Hospital), Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China
| | - L Lu
- Department of Endocrinology, Key Laboratory of Endocrinology, National Health Commission (NHC), Peking Union Medical College Hospital), Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China
| | - Y Cao
- Department of Endocrinology, Key Laboratory of Endocrinology, National Health Commission (NHC), Peking Union Medical College Hospital), Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China
| | - W Zhang
- Department of Endocrinology, Key Laboratory of Endocrinology, National Health Commission (NHC), Peking Union Medical College Hospital), Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China
| | - B Sun
- Department of Endocrinology, Key Laboratory of Endocrinology, National Health Commission (NHC), Peking Union Medical College Hospital), Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China
| | - X Wu
- Department of Endocrinology, Key Laboratory of Endocrinology, National Health Commission (NHC), Peking Union Medical College Hospital), Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China
| | - A Tong
- Department of Endocrinology, Key Laboratory of Endocrinology, National Health Commission (NHC), Peking Union Medical College Hospital), Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China
| | - S Chen
- Department of Endocrinology, Key Laboratory of Endocrinology, National Health Commission (NHC), Peking Union Medical College Hospital), Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China
| | - X Wang
- Department of Endocrinology, Key Laboratory of Endocrinology, National Health Commission (NHC), Peking Union Medical College Hospital), Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China
| | - J Mao
- Department of Endocrinology, Key Laboratory of Endocrinology, National Health Commission (NHC), Peking Union Medical College Hospital), Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China
| | - M Nie
- Department of Endocrinology, Key Laboratory of Endocrinology, National Health Commission (NHC), Peking Union Medical College Hospital), Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China.
- State Key Laboratory of Complex, Severe and Rare Diseases, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China.
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Ravichandran L, Asha HS, Mathai S, Thomas N, Chapla A. Congenital Adrenal Hyperplasia - A Comprehensive Review of Genetic Studies on 21-Hydroxylase Deficiency from India. Indian J Endocrinol Metab 2024; 28:117-128. [PMID: 38911104 PMCID: PMC11189293 DOI: 10.4103/ijem.ijem_303_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 09/23/2023] [Accepted: 02/06/2024] [Indexed: 06/25/2024] Open
Abstract
Congenital adrenal hyperplasia (CAH) comprises a heterogeneous group of autosomal recessive disorders impairing adrenal steroidogenesis. Most cases are caused by mutations in the CYP21A2 gene resulting in 21-hydroxylase (21-OH) deficiency (21-OHD). The genetics of 21-OH CAH is complexed by a highly homologous pseudogene CYP21A1P imposing several limitations in the molecular analysis. Therefore, genetic testing is still not a part of routine CAH diagnosis and is mainly dependent on 17-hydroxy progesterone (OHP) measurements. There are very few reports of CYP21A2 gene analysis from India and there is no comprehensive review available on genetic testing and the spectrum of CYP21A2 mutations from the country. This review focuses on the molecular aspects of 21-OHD and the genetic studies on CYP21A2 gene reported from India. The results of these studies insist the compelling need for large-scale CYP21A2 genetic testing and newborn screening (NBS) in India. With a high disease prevalence and consanguinity rates, robust and cost-effective genetic testing for 21-OH CAH would enable an accurate diagnosis in routine clinical practice. Whereas establishing affordable genotyping assays even in secondary care or resource-poor settings of the country can identify 90% of the mutations that are pseudogene derived, initiatives on reference laboratories for CAH across the nation with comprehensive genetic testing facilities will be beneficial in those requiring extended analysis of CYP21A2 gene. Further to this, incorporating genetic testing in NBS and carrier screening programmes will enable early diagnosis, better risk assessment and community-based management.
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Affiliation(s)
- Lavanya Ravichandran
- Department of Endocrinology, Diabetes and Metabolism, Christian Medical College, Vellore, Tamil Nadu, India
- DBT-Regional Centre for Biotechnology (RCB), Faridabad, Haryana, India
| | - Hesarghatta S. Asha
- Department of Endocrinology, Diabetes and Metabolism, Christian Medical College, Vellore, Tamil Nadu, India
| | - Sarah Mathai
- Department of Pediatric Endocrinology, Christian Medical College, Vellore, Tamil Nadu, India
| | - Nihal Thomas
- Department of Endocrinology, Diabetes and Metabolism, Christian Medical College, Vellore, Tamil Nadu, India
- DBT-Regional Centre for Biotechnology (RCB), Faridabad, Haryana, India
| | - Aaron Chapla
- Department of Endocrinology, Diabetes and Metabolism, Christian Medical College, Vellore, Tamil Nadu, India
- DBT-Regional Centre for Biotechnology (RCB), Faridabad, Haryana, India
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Li Y, Gong Y, Zhou Y, Xiao Y, Huang W, Zhou Q, Tu Y, Zhao Y, Zhang S, Dai L, Sun Q. STK19 is a DNA/RNA-binding protein critical for DNA damage repair and cell proliferation. J Cell Biol 2024; 223:e202301090. [PMID: 38252411 PMCID: PMC10806857 DOI: 10.1083/jcb.202301090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 08/15/2023] [Accepted: 11/10/2023] [Indexed: 01/23/2024] Open
Abstract
STK19 was originally identified as a manganese-dependent serine/threonine-specific protein kinase, but its function has been highly debated. Here, the crystal structure of STK19 revealed that it does not contain a kinase domain, but three intimately packed winged helix (WH) domains. The third WH domain mediated homodimerization and double-stranded DNA binding, both being important for its nuclear localization. STK19 participated in the nucleotide excision repair (NER) and mismatch repair (MMR) pathways by recruiting damage repair factors such as RPA2 and PCNA. STK19 also bound double-stranded RNA through the DNA-binding interface and regulated the expression levels of many mRNAs. Furthermore, STK19 knockdown cells exhibited very slow cell proliferation, which cannot be rescued by dimerization or DNA-binding mutants. Therefore, this work concludes that STK19 is highly unlikely to be a kinase but a DNA/RNA-binding protein critical for DNA damage repair (DDR) and cell proliferation. To prevent further confusions, we renamed this protein as TWH19 (Tandem Winged Helix protein formerly known as STK19).
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Affiliation(s)
- Yuling Li
- Department of Pulmonary and Critical Care Medicine, Sichuan Provincial People’s Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
- Department of Pathology, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University and Collaborative Innovation Center of Biotherapy, Chengdu, China
| | - Yanqiu Gong
- National Clinical Research Center for Geriatrics and Department of General Practice, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, and Collaborative Innovation Center of Biotherapy, Chengdu, China
| | - Yue Zhou
- National Chengdu Center for Safety Evaluation of Drugs, State Key Laboratory of Biotherapy/Collaborative Innovation Center for Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Yuzhou Xiao
- National Chengdu Center for Safety Evaluation of Drugs, State Key Laboratory of Biotherapy/Collaborative Innovation Center for Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Wenxin Huang
- Department of Pathology, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University and Collaborative Innovation Center of Biotherapy, Chengdu, China
| | - Qiao Zhou
- Department of Pathology, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University and Collaborative Innovation Center of Biotherapy, Chengdu, China
| | - Yingfeng Tu
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, China
| | - Yinglan Zhao
- National Chengdu Center for Safety Evaluation of Drugs, State Key Laboratory of Biotherapy/Collaborative Innovation Center for Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Shuyu Zhang
- The Second Affiliated Hospital of Chengdu Medical College, China National Nuclear Corporation 416 Hospital, Chengdu, China
| | - Lunzhi Dai
- National Clinical Research Center for Geriatrics and Department of General Practice, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, and Collaborative Innovation Center of Biotherapy, Chengdu, China
| | - Qingxiang Sun
- Department of Pulmonary and Critical Care Medicine, Sichuan Provincial People’s Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
- Department of Pathology, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University and Collaborative Innovation Center of Biotherapy, Chengdu, China
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Fraga NR, Minaeian N, Kim MS. Congenital Adrenal Hyperplasia. Pediatr Rev 2024; 45:74-84. [PMID: 38296783 DOI: 10.1542/pir.2022-005617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2024]
Abstract
We describe congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency, which is the most common primary adrenal insufficiency in children and adolescents. In this comprehensive review of CAH, we describe presentations at different life stages depending on disease severity. CAH is characterized by androgen excess secondary to impaired steroidogenesis in the adrenal glands. Diagnosis of CAH is most common during infancy with elevated 17-hydroxyprogesterone levels on the newborn screen in the United States. However, CAH can also present in childhood, with late-onset symptoms such as premature adrenarche, growth acceleration, hirsutism, and irregular menses. The growing child with CAH is treated with hydrocortisone for glucocorticoid replacement, along with increased stress doses for acute illness, trauma, and procedures. Mineralocorticoid and salt replacement may also be necessary. Although 21-hydroxylase deficiency is the most common type of CAH, there are other rare types, such as 11β-hydroxylase and 3β-hydroxysteroid dehydrogenase deficiency. In addition, classic CAH is associated with long-term comorbidities, including cardiometabolic risk factors, impaired cognitive function, adrenal rest tumors, and bone health effects. Overall, early identification and treatment of CAH is important for the pediatric patient.
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Affiliation(s)
- Nicole R Fraga
- Center for Endocrinology, Diabetes, and Metabolism, Children's Hospital Los Angeles, Los Angeles, CA
| | - Nare Minaeian
- Center for Endocrinology, Diabetes, and Metabolism, Children's Hospital Los Angeles, Los Angeles, CA
- Keck School of Medicine of University of Southern California, Los Angeles, CA
| | - Mimi S Kim
- Center for Endocrinology, Diabetes, and Metabolism, Children's Hospital Los Angeles, Los Angeles, CA
- Keck School of Medicine of University of Southern California, Los Angeles, CA
- The Saban Research Institute at Children's Hospital Los Angeles, Los Angeles, CA
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Concolino P, Perrucci A, Carrozza C, Urbani A. Genetic Characterization of a Cohort of Italian Patients with Congenital Adrenal Hyperplasia Due to 21-Hydroxylase Deficiency. Mol Diagn Ther 2023; 27:621-630. [PMID: 37548905 DOI: 10.1007/s40291-023-00666-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/12/2023] [Indexed: 08/08/2023]
Abstract
INTRODUCTION Defects in the steroid 21-hydroxylase gene (CYP21A2) cause 21-hydroxylase deficiency (21OHD), the main cause of congenital adrenal hyperplasia (CAH). The disease shows a broad spectrum of clinical forms, ranging from severe or classical (salt wasting, SW, and simple virilizing, SV), to mild late onset or nonclassical (NC). 21OHD affects 1 in 15,000 in its severe classic form and 1 in 200-1000 in its mild NC form. There are many studies reporting the frequency of CYP21A2 pathogenic variants in different populations; however, few of them provide comprehensive information about Italian patients. Here, we present genetic results from a cohort of 245 unrelated Italian individuals with clinical diagnosis of CAH due to 21OHD. METHODS A specific polymerase chain reaction (PCR) protocol combined with Sanger sequencing was used for CYP21A2 analysis. The multiplex ligation-dependent probe amplification (MLPA) assay was employed for copy number variation (CNV) determination. RESULTS One hundred fourteen (46.5%) of the index cases had the NC form, 57 (23.3%) had the SV form, and 74 (30.2%) presented the SW form of the disease. The most prevalent variant found in NC patients was the p.Val282Leu (51.3%), while the most frequent variants in the classical form were p.Ile173Asn (8.6%) and c.293-13C>G (26.0%). In our study, the frequency of large rearrangements was 15.3%, with CAH-X alleles representing 40% of all DEL/CONV. In addition, 12 alleles carried rare variants, and 1 had a novel variant p.(Arg342Gln). We observed phenotype-genotype correlation in 94.7% of cases. A complete concordance was observed in Groups 0 (enzyme activity completely impaired) where all patients had the SW form as expected. In Group A (0-1% residual enzyme activity), 78.4% of patients had the anticipated SW form while 21.6% were diagnosed with the SV form. Within Group B (~ 2% residual enzyme activity), 93.4% of patients exhibited SV form and 6.5% SW disease. Finally, 92.6% and 7.4% of patients belonging to Group C (enzyme partially impaired to ~ 20-60% residual activity) exhibited NC and SV phenotypes, respectively. CONCLUSION This work, representing a comprehensive genetic study, expanded the CYP21A2 variants spectrum of Italian patients with 21OHD and could be helpful in prenatal diagnosis and genetic counseling.
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Affiliation(s)
- Paola Concolino
- Clinical Chemistry, Biochemistry and Molecular Biology Operations (UOC), Agostino Gemelli Foundation University Hospital IRCCS, Largo A. Gemelli 8, 00168, Rome, Italy.
| | - Alessia Perrucci
- Clinical Chemistry, Biochemistry and Molecular Biology Operations (UOC), Agostino Gemelli Foundation University Hospital IRCCS, Largo A. Gemelli 8, 00168, Rome, Italy
| | - Cinzia Carrozza
- Clinical Chemistry, Biochemistry and Molecular Biology Operations (UOC), Agostino Gemelli Foundation University Hospital IRCCS, Largo A. Gemelli 8, 00168, Rome, Italy
- Department of Basic Biotechnological Sciences, Intensivological and Perioperative Clinics, Catholic University of Sacred Heart, Rome, Italy
| | - Andrea Urbani
- Clinical Chemistry, Biochemistry and Molecular Biology Operations (UOC), Agostino Gemelli Foundation University Hospital IRCCS, Largo A. Gemelli 8, 00168, Rome, Italy
- Department of Basic Biotechnological Sciences, Intensivological and Perioperative Clinics, Catholic University of Sacred Heart, Rome, Italy
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Kim JH, Kim GH, Yoo HW, Choi JH. Molecular basis and genetic testing strategies for diagnosing 21-hydroxylase deficiency, including CAH-X syndrome. Ann Pediatr Endocrinol Metab 2023; 28:77-86. [PMID: 37401054 DOI: 10.6065/apem.2346108.054] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 05/22/2022] [Indexed: 07/05/2023] Open
Abstract
Congenital adrenal hyperplasia (CAH) is a group of autosomally recessive disorders that result from impaired synthesis of glucocorticoid and mineralocorticoid. Most cases (~95%) are caused by mutations in the CYP21A2 gene, which encodes steroid 21-hydroxylase. CAH patients manifest a wide phenotypic spectrum according to their degree of residual enzyme activity. CYP21A2 and its pseudogene (CYP21A1P) are located 30 kb apart in the 6q21.3 region and share approximately 98% of their sequences in the coding region. Both genes are aligned in tandem with the C4, SKT19, and TNX genes, forming 2 segments of the RCCX modules that are arranged as STK19-C4A-CYP21A1P-TNXA-STK19B-C4B-CYP21A2-TNXB. The high sequence homology between the active gene and pseudogene leads to frequent microconversions and large rearrangements through intergenic recombination. The TNXB gene encodes an extracellular matrix glycoprotein, tenascin-X (TNX), and defects in TNXB cause Ehlers-Danlos syndrome. Deletions affecting both CYP21A2 and TNXB result in a contiguous gene deletion syndrome known as CAH-X syndrome. Because of the high homology between CYP21A2 and CYP21A1P, genetic testing for CAH should include an evaluation of copy number variations, as well as Sanger sequencing. Although it poses challenges for genetic testing, a large number of mutations and their associated phenotypes have been identified, which has helped to establish genotype-phenotype correlations. The genotype is helpful for guiding early treatment, predicting the clinical phenotype and prognosis, and providing genetic counseling. In particular, it can help ensure proper management of the potential complications of CAH-X syndrome, such as musculoskeletal and cardiac defects. This review focuses on the molecular pathophysiology and genetic diagnosis of 21-hydroxylase deficiency and highlights genetic testing strategies for CAH-X syndrome.
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Affiliation(s)
- Ja Hye Kim
- Department of Pediatrics, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Gu-Hwan Kim
- Medical Genetics Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Han-Wook Yoo
- Department of Pediatrics, Bundang CHA Medical Center, CHA University, Seongnam, Korea
| | - Jin-Ho Choi
- Department of Pediatrics, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
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Fanis P, Skordis N, Toumba M, Picolos M, Tanteles GA, Neocleous V, Phylactou LA. The pathogenic p.Gln319Ter variant is not causing congenital adrenal hyperplasia when inherited in one of the duplicated CYP21A2 genes. Front Endocrinol (Lausanne) 2023; 14:1156616. [PMID: 37324257 PMCID: PMC10266209 DOI: 10.3389/fendo.2023.1156616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 05/04/2023] [Indexed: 06/17/2023] Open
Abstract
Objective The study aimed to identify the pathogenic status of p.Gln319Ter (NM_000500.7: c.955C>T) variant when inherited in a single CYP21A2 gene (bimodular RCCX haplotype) and to discriminate between a non-causing congenital adrenal hyperplasia (CAH) allele when inherited in a duplicated and functional CYP21A2 gene context (trimodular RCCX haplotype). Methods 38 females and 8 males with hyperandrogenemia, previously screened by sequencing and identified as carriers for the pathogenic p.Gln319Ter, were herein tested by multiplex ligation-dependent probe amplification (MLPA) and a real-time PCR Copy number Variation (CNV) assay. Results Both MLPA and real-time PCR CNV analyses confirmed a bimodular and pathogenic RCCX haplotype with a single CYP21A2 in 19/46 (41.30%) p.Gln319Ter carriers and who in parallel all shared elevated 17-OHP levels. The remaining 27 individuals that also carried the p.Gln319Ter exhibited low 17-OHP levels as a result of their carriership of a duplicated CYP21A2 with a trimodular RCCX haplotype. Interestingly, all of these individuals also carried in linkage disequilibrium with p.Gln319Ter two single nucleotide polymorphisms, the c.293-79G>A (rs114414746) in intron 2 and the c.*12C>T (rs150697472) in the 3'-UTR. Therefore, these variants can be used to distinguish between pathogenic and non-pathogenic genomic contexts of the c.955T (p.Gln319) in the genetic diagnosis of congenital adrenal hyperplasia (CAH). Conclusion The employed methodologies identified a considerable number of individuals with non-pathogenic p.Gln319Ter from the individuals that typically carry the pathogenic p.Gln319Ter in a single CYP21A2. Therefore, it is extremely important the detection of such haplotypes for the prenatal diagnosis, treatment and genetic counseling in patients with CAH.
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Affiliation(s)
- Pavlos Fanis
- 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
- Division of Paediatric Endocrinology, Paedi Center for specialized Paediatrics, Nicosia, Cyprus
- School of Medicine, University of Nicosia, Nicosia, Cyprus
| | - Meropi Toumba
- Department of Molecular Genetics, Function and Therapy, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
- Department of Paediatrics, Paediatric Endocrinology Clinic, Aretaeio Hospital, Nicosia, Cyprus
| | - Michalis Picolos
- Department of Endocrinology, Alithias Endocrinology Center, Nicosia, Cyprus
| | - George A. Tanteles
- Department of Clinical Genetics, 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
| | - Leonidas A. Phylactou
- Department of Molecular Genetics, Function and Therapy, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
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Lao Q, Burkardt DD, Kollender S, Faucz FR, Merke DP. Congenital adrenal hyperplasia due to two rare CYP21A2 variant alleles, including a novel attenuated CYP21A1P/CYP21A2 chimera. Mol Genet Genomic Med 2023:e2195. [PMID: 37157918 DOI: 10.1002/mgg3.2195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 04/05/2023] [Accepted: 04/25/2023] [Indexed: 05/10/2023] Open
Abstract
BACKGROUND Congenital adrenal hyperplasia (CAH) due to 21-hydroxylase (21OH) deficiency is an autosomal recessive inborn error of cortisol biosynthesis, with varying degrees of aldosterone production. There is a continuum of phenotypes which generally correlate with genotype and the expected residual 21OH activity of the less severely impaired allele. CYP21A1P/CYP21A2 chimeric genes caused by recombination between CYP21A2 and its highly homologous CYP21A1P pseudogene are common in CAH and typically associated with salt-wasting CAH, the most severe form. Nine chimeras have been described (CH-1 to CH-9). AIMS The aim of this study was to genetically evaluate two variant alleles carried by a 22-year-old female with the non-salt-wasting simple virilizing form of CAH and biallelic 30-kb deletions. METHODS The haplotypes of the CYP21A2 heterozygous variants, as well as the chimeric junction sites, were determined by Sanger sequencing TA clones of an allele-specific PCR product. RESULTS Genetic testing revealed two rare CYP21A1P/CYP21A2 chimeras: allele 1 matches the previously described CAH CH-1 chimera but without the P30L variant, and allele 2, termed here as novel CAH CH-10, has a junction site between c.293-37 and c.29314, which is expected to retain partial 21OH activity. CONCLUSION These two variant alleles further document the complex nature of RCCX modules and highlight that not all CYP21A1P/CYP21A2 chimera severely impair 21OH activity.
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Affiliation(s)
- Qizong Lao
- National Institutes of Health Clinical Center, Bethesda, Maryland, USA
| | | | - Sarah Kollender
- National Institutes of Health Clinical Center, Bethesda, Maryland, USA
| | - Fabio R Faucz
- The Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA
| | - Deborah P Merke
- National Institutes of Health Clinical Center, Bethesda, Maryland, USA
- The Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA
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Xia Y, Shi P, Gao S, Liu N, Zhang H, Kong X. Genetic analysis and novel variation identification in Chinese patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency. J Steroid Biochem Mol Biol 2022; 222:106156. [PMID: 35882282 DOI: 10.1016/j.jsbmb.2022.106156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 06/30/2022] [Accepted: 07/18/2022] [Indexed: 11/24/2022]
Abstract
Congenital adrenal hyperplasia owing to 21-hydroxylase deficiency is an autosomal-recessive disorder caused by mutations in the CYP21A2 gene. The aim of the study was to analyze the molecular data of 155 21-OHD patients and retrospectively investigated the common allelic mutations of CYP21A2 in 1442 Chinese 21-OHD patients. Clinical features and mutations of CYP21A2 gene in 155 unrelated 21-OHD patients were examined. Of the 155 patients, 103 cases were salt-wasting (SW) forms, 38 were simple virilizing (SV) forms and 14 were non-classical (NC) forms. In general, two types of mutations including common allelic mutations (281/310, 90.6%) and rare mutations (29/310, 9.4%) were detected, among them four novel variants c.835G>T, c.1081C>T, c.1423C>T and c.651 + 2 T > G were identified. In 1442 Chinese 21-OHD patients, the most frequently mutations were I2G (36.2%), large deletion/conversion (20.7%) and p.I173N (17.8%), while p.V282L has the lowest frequency. In this study, we provided detailed clinical data and mutation spectrum in Chinese 21-OHD patients. Moreover, four novel CYP21A2 variants (c.835G>T, c.1081C>T, c.1423C>T and c.651 +2 T > G) were identified and computational structural modeling indicated that these novel variations probably affect structural stability. Our findings improve the understanding of CYP21A2 mutational spectrum and contribute to the precise diagnosis and prenatal counseling.
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Affiliation(s)
- Yanjie Xia
- Genetics and Prenatal Diagnosis Center, The First Affiliated Hospital of Zhengzhou University, Henan Engineering Research Center for Gene Editing of Human Genetic Disease, Zhengzhou, China
| | - Panlai Shi
- Genetics and Prenatal Diagnosis Center, The First Affiliated Hospital of Zhengzhou University, Henan Engineering Research Center for Gene Editing of Human Genetic Disease, Zhengzhou, China
| | - Shanshan Gao
- Genetics and Prenatal Diagnosis Center, The First Affiliated Hospital of Zhengzhou University, Henan Engineering Research Center for Gene Editing of Human Genetic Disease, Zhengzhou, China
| | - Ning Liu
- Genetics and Prenatal Diagnosis Center, The First Affiliated Hospital of Zhengzhou University, Henan Engineering Research Center for Gene Editing of Human Genetic Disease, Zhengzhou, China
| | - Huijuan Zhang
- Department of Endocrinology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Xiangdong Kong
- Genetics and Prenatal Diagnosis Center, The First Affiliated Hospital of Zhengzhou University, Henan Engineering Research Center for Gene Editing of Human Genetic Disease, Zhengzhou, China.
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Prevalence of CAH-X Syndrome in Italian Patients with Congenital Adrenal Hyperplasia (CAH) Due to 21-Hydroxylase Deficiency. J Clin Med 2022; 11:jcm11133818. [PMID: 35807105 PMCID: PMC9267771 DOI: 10.3390/jcm11133818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 06/23/2022] [Accepted: 06/28/2022] [Indexed: 11/17/2022] Open
Abstract
21-hydroxylase deficiency (21OHD), the most common form of congenital adrenal hyperplasia (CAH), is associated with pathogenic variants in CYP21A2 gene. The clinical form of the disease ranges from classic or severe to non-classic (NC) or mild late onset. The CYP21A2 gene is located on the long arm of chromosome 6, within the RCCX region, one of the most complex loci in the human genome. The 3′untranslated sequence of CYP21A2 exon 10 overlap the last exon of TNXB gene (these genes lie on the opposite strands of DNA and have the opposite transcriptional direction) that encodes an extracellular matrix glycoprotein tenascin-X (TNX). A recombination event between TNXB and its pseudogene TNXA causes a 30 kb deletion producing a chimeric TNXA/TNXB gene (CAH-X chimera) where both CYP21A2 and TNXB genes are impaired. This genetic condition characterizes a subset of patients with 21OHD who display the hypermobility phenotype of Ehlers–Danlos syndrome (hEDS) (CAH-X Syndrome). The aim of this study was to assess the prevalence of CAH-X syndrome in an Italian cohort of patients with 21OHD. At this purpose, 196 probands were recruited. Multiplex ligation-dependent probe amplification (MLPA) and Sanger sequencing were used to identify the CAH-X genotype. Twenty-one individuals showed the heterozygous continuous deletion involving the CYP21A2 and part of the TNXB gene. EDS-related clinical manifestations were identified in most patients carrying the CAH-X chimera. A CAH-X prevalence of 10.7% was estimated in our population.
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Tantirukdham N, Sahakitrungruang T, Chaisiwamongkol R, Pongpanich M, Srichomthong C, Assawapitaksakul A, Buasong A, Tongkobpetch S, Yeetong P, Shotelersuk V. Long-read Amplicon Sequencing of the CYP21A2 in 48 Thai Patients With Steroid 21-Hydroxylase Deficiency. J Clin Endocrinol Metab 2022; 107:1939-1947. [PMID: 35363313 DOI: 10.1210/clinem/dgac187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Indexed: 11/19/2022]
Abstract
CONTEXT Congenital adrenal hyperplasia is most commonly caused by 21-hydroxylase deficiency (21-OHD), an autosomal recessive disorder resulting from biallelic pathogenic variants (PVs) in CYP21A2. With a highly homologous pseudogene and various types of single nucleotide and complex structural variants, identification of PVs in CYP21A2 has been challenging. OBJECTIVE To leverage long-read next-generation sequencing combined with locus-specific polymerase chain reaction (PCR) to detect PVs in CYP21A2 and to determine its diagnostic yield in patients with 21-OHD. METHODS Forty-eight Thai patients with 21-OHD comprising 38 sporadic cases and 5 pairs of siblings were enrolled. Two previously described locus-specific PCR methods were performed. Amplicons were subject to long-read sequencing. RESULTS Ninety-six PVs in CYP21A2 in the 48 patients were successfully identified. The combined techniques were able to detect 26 structural chimeric variants (27%; 26/96) in 22 patients with 18 having monoallelic and 4 having biallelic chimeras. The remaining PVs were pseudogene-derived mutations (63%; 60/96), entire gene deletions (2%; 2/96), missense variants (3%; 3/96), a splice-site variant (2%; 2/96), frameshift variants (2%; 2/96), and a nonsense variant (1%; 1/96). Notably, a splice-site variant, IVS7 + 1G > T, which was identified in a pair of siblings, has not previously been reported. CONCLUSIONS Our approach exploiting locus-specific PCR and long-read DNA sequencing has a 100% diagnostic yield for our cohort of 48 patients with 21-OHD.
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Affiliation(s)
- Nithiphut Tantirukdham
- Genetics Program, Division of Human Genetics, Department of Botany, Faculty of Science, Chulalongkorn University, Bangkok, Thailand
- Molecular and Genomics Research Laboratory, Chulabhorn Learning and Research Centre, Chulabhorn Royal Academy, Bangkok, Thailand
| | - Taninee Sahakitrungruang
- Division of Pediatric Endocrinology, Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Ratikorn Chaisiwamongkol
- Division of Pediatric Endocrinology, Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Monnat Pongpanich
- Department of Mathematics and Computer Science, Faculty of Science, Chulalongkorn University, Bangkok, Thailand
- Omics Sciences and Bioinformatics Center, Faculty of Science, Chulalongkorn University, Bangkok, Thailand
| | - Chalurmpon Srichomthong
- Center of Excellence for Medical Genomics, Medical Genomics Cluster, Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
- Excellence Center for Genomics and Precision Medicine, King Chulalongkorn Memorial Hospital, the Thai Red Cross Society, Bangkok, Thailand
| | - Adjima Assawapitaksakul
- Center of Excellence for Medical Genomics, Medical Genomics Cluster, Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
- Excellence Center for Genomics and Precision Medicine, King Chulalongkorn Memorial Hospital, the Thai Red Cross Society, Bangkok, Thailand
| | - Aayalida Buasong
- Center of Excellence for Medical Genomics, Medical Genomics Cluster, Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
- Excellence Center for Genomics and Precision Medicine, King Chulalongkorn Memorial Hospital, the Thai Red Cross Society, Bangkok, Thailand
| | - Siraprapa Tongkobpetch
- Center of Excellence for Medical Genomics, Medical Genomics Cluster, Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
- Excellence Center for Genomics and Precision Medicine, King Chulalongkorn Memorial Hospital, the Thai Red Cross Society, Bangkok, Thailand
| | - Patra Yeetong
- Division of Human Genetics, Department of Botany, Faculty of Science, Chulalongkorn University, Bangkok, Thailand
| | - Vorasuk Shotelersuk
- Center of Excellence for Medical Genomics, Medical Genomics Cluster, Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
- Excellence Center for Genomics and Precision Medicine, King Chulalongkorn Memorial Hospital, the Thai Red Cross Society, Bangkok, Thailand
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Abstract
The term CAH-X was coined to describe a subset of patients with 21-hydroxylase deficiency displaying a phenotype compatible with the hypermobility type of Ehlers Danlos syndrome. The genetic defect is due to the monoallelic presence of a CYP21A2 deletion extending into the gene encoding tenascin X (TNXB), a connective tissue extracellular matrix protein. The result is a chimeric TNXA/TNXB gene causing tenascin-X haploinsufficiency. The prevalence of CAH-X was estimated to be around 14-15% in large cohorts of patients with 21-hydroxylase deficiency. However, population studies are still scarce and the clinical picture of the syndrome has yet to be fully defined. In this review, we discuss the current knowledge regarding the genetic and clinical profile of the CAH-X syndrome.
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Marino R, Moresco A, Perez Garrido N, Ramirez P, Belgorosky A. Congenital Adrenal Hyperplasia and Ehlers-Danlos Syndrome. Front Endocrinol (Lausanne) 2022; 13:803226. [PMID: 35282436 PMCID: PMC8913572 DOI: 10.3389/fendo.2022.803226] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 01/31/2022] [Indexed: 11/13/2022] Open
Abstract
Congenital adrenal hyperplasia (CAH) secondary to 21-hydroxylase deficiency is an autosomal recessive disorder. The 21-hydroxylase enzyme P450c21 is encoded by the CYP21A2 gene located on chromosome 6p21.33 within the HLA major histocompatibility complex. This locus also contains the CYP21A1P, a non-functional pseudogene, that is highly homologous to the CYP21A2 gene. Other duplicated genes are C4A and C4B, that encode two isoforms of complement factor C4, the RP1 gene that encodes a serine/threonine protein kinase, and the TNXB gene that, encodes the extracellular matrix glycoprotein tenascin-X (TNX). TNX plays a role in collagen deposition by dermal fibroblasts and is expressed in the dermis of the skin and the connective tissue of the heart and skeletal muscle. During meiosis, misalignment may occur producing large gene deletions or gene conversion events resulting in chimeric genes. Chimeric recombination may occur between TNXB and TNXA. Three TNXA/TNXB chimeras have been described that differ in the junction site (CH1 to CH3) and result in a contiguous CYP21A2 and TNXB gene deletion, causing CAH-X syndrome. TNXB deficiency is associated with Ehlers Danlos syndrome (EDS). EDS comprises a clinically and genetically heterogeneous group of connective tissue disorders. As molecular analysis of the TNXB gene is challenging, the TNX-deficient type EDS is probably underdiagnosed. In this minireview, we will address the different strategies of molecular analysis of the TNXB-gene, as well as copy number variations and genetic status of TNXB in different cohorts. Furthermore, clinical features of EDS and clinical recommendations for long-term follow-up are discussed.
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Affiliation(s)
- Roxana Marino
- Molecular Biology Laboratory, Endocrinology Service, Hospital de Pediatría Prof. Dr. Juan P. Garrahan, Buenos Aires, Argentina
| | - Angélica Moresco
- Genetics Service, Hospital de Pediatría Prof. Dr. Juan P. Garrahan, Buenos Aires, Argentina
| | - Natalia Perez Garrido
- Molecular Biology Laboratory, Endocrinology Service, Hospital de Pediatría Prof. Dr. Juan P. Garrahan, Buenos Aires, Argentina
| | - Pablo Ramirez
- Molecular Biology Laboratory, Endocrinology Service, Hospital de Pediatría Prof. Dr. Juan P. Garrahan, Buenos Aires, Argentina
| | - Alicia Belgorosky
- Endocrinology Service, Hospital de Pediatría Prof. Dr. Juan P. Garrahan, Buenos Aires, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
- *Correspondence: Alicia Belgorosky,
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