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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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Congenital Adrenal Hyperplasia (CAH) and Gitelman Syndrome (GS): Overlapping Symptoms in an Uncommon Association. Case Rep Pediatr 2021; 2021:6633541. [PMID: 33763274 PMCID: PMC7964118 DOI: 10.1155/2021/6633541] [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: 11/11/2020] [Revised: 02/22/2021] [Accepted: 03/02/2021] [Indexed: 11/18/2022] Open
Abstract
Background Classical salt-wasting (SW) congenital adrenal hyperplasia (CAH) and Gitelman syndrome (GS) are two genetic conditions in which dyselectrolytemia may occur. No association between the two conditions has been previously described. Case Presentation. We present the case of a boy with a neonatal diagnosis of SW-CAH who showed low potassium blood levels from the age of 15 years. This electrolytic alteration was, at first, attributed to an excessive action of mineralocorticoid drugs. Due to persistence of hypokalemia, SLC12A3 whole genome sequencing was performed, showing a heterozygous C to T base pair substitution at position 965 in gene SLC12A3. This mutation is related to Gitelman syndrome with autosomal recessive transmission. Conclusions SW-CAH and GS determine opposite values of potassium in the absence of specific therapy, with a natural tendency to compensate each other. The symptom overlap makes diagnosis difficult. Organic causes of hypokalemia in patients undergoing life-saving therapy should not be excluded.
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Gangodkar P, Khadilkar V, Raghupathy P, Kumar R, Dayal AA, Dayal D, Ayyavoo A, Godbole T, Jahagirdar R, Bhat K, Gupta N, Kamalanathan S, Jagadeesh S, Ranade S, Lohiya N, Oke RL, Ganesan K, Khatod K, Agarwal M, Phadke N, Khadilkar A. Clinical application of a novel next generation sequencing assay for CYP21A2 gene in 310 cases of 21- hydroxylase congenital adrenal hyperplasia from India. Endocrine 2021; 71:189-198. [PMID: 32948948 DOI: 10.1007/s12020-020-02494-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Accepted: 09/07/2020] [Indexed: 10/23/2022]
Abstract
PURPOSE Accurate diagnosis is required for management of Congenital adrenal hyperplasia (CAH). The conventional method for detection of mutations in the CYP21A2 gene is targeted capillary sequencing which is labor intensive and has limited multiplexing capability. Next generation sequencing (NGS) provides data with high sequence coverage and depth. Our objective was to develop an accurate NGS-based assay to characterize the mutation spectrum in CYP21A2 gene in Indian patients suspected to have 21-OH CAH. METHODS Cases with 21-OH CAH from 12 endocrine units across India were studied. DNA was extracted from proband's and parent's(subset) blood. Locus-specific long-range PCR and gel electrophoresis of amplicons was followed by NGS where no visible 30 kb homozygous/whole gene deletion was observed. Orthogonal confirmation was performed by capillary sequencing (ABI 3500) and Multiplex Ligation-dependent Probe Amplification (MLPA, MRC-Holland). PCR products were purified and individual libraries were pooled and sequenced (Illumina). RESULTS Of the 310 CAH cases, biallelic mutations (pathogenic/ likely pathogenic variants involving both CYP21A2 gene copies) were detected in 256 (82.6%), heterozygous mutations in 13 (4.2 %), and none in 41 (13.2%). Most common mutation was c.293-13A/C>G (29.03%), followed by 30 kb deletion (18.24%). Thirty samples tested orthogonally (by capillary sequencing or MLPA) showed 100% concordance with NGS assay. Nine novel variants were identified. CONCLUSIONS We have developed and validated a comprehensive NGS-based assay for detection of variants in CYP21A2 gene in patients with 21-OH CAH. We describe CYP21A2 mutation spectrum and novel variants in a large cohort of Indian patients with CAH.
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Affiliation(s)
- Priyanka Gangodkar
- Research Scientist, GenePath Diagnostics India Private Limited, Pune, Maharashtra, India
| | - Vaman Khadilkar
- Consultant Pediatric Endocrinologist, Hirabai Cowasji Jehangir Medical Research Institute, Jehangir hospital, Pune, Maharashtra, India
| | - P Raghupathy
- Pediatric Endocrinologist, Indira Gandhi Institute of Child Health, Bengaluru, Karnataka, India
| | - Rakesh Kumar
- Endocrinology and Diabetes Unit, Department of Pediatrics, Advanced Pediatrics Centre, Post Graduate Institute of Medical Education and Research (PGIMER), Sector 12, Chandigarh, India
| | - Archana Arya Dayal
- Consultant Pediatric Endocrinologist, Sir Gangaram Hospital, Delhi, India
| | - Devi Dayal
- Pediatric Endocrinology & Diabetes Unit, PGIMER, Chandigarh, India
| | - Ahila Ayyavoo
- Consultant Pediatric Endocrinologist and Diabetologist, GKNM hospital, Coimbatore, Tamil Nadu, India
| | - Tushar Godbole
- Consultant Pediatric Endocrinologist, Harmony Health Hub, Nashik, Maharashtra, India
| | - Rahul Jahagirdar
- Professor and Pediatric Endocrinologist, Bharati Vidyapeeth University Medical College, Pune, Maharashtra, India
| | - Kavitha Bhat
- Chief Pediatric Endocrinologist, Rainbow Children's Hospital, Bengaluru, Karnataka, India
| | - Neerja Gupta
- Division of Genetics, Department of Pediatrics, AIIMS, New Delhi, India
| | | | - Sujatha Jagadeesh
- Consultant, Medical Geneticist & dysmorphologist, Mediscan, Chennai, Tamil Nadu, India
| | - Shatakshi Ranade
- Senior Research Scientist, GenePath Diagnostics india Private Limited, Pune, Maharashtra, India
| | - Nikhil Lohiya
- Fellow in Pediatric Endocrinology, Hirabai Cowasji Jehangir Medical Research Institute, Jehangir hospital, Pune, Maharashtra, India
| | - Rashmi Lote Oke
- Research Scientist, Hirabai Cowasji Jehangir Medical Research Institute, Jehangir hospital, Pune, Maharashtra, India
| | - Karthik Ganesan
- Chief Technology Officer, GenePath Diagnostics Inc., Pune, India
| | - Kavita Khatod
- Head of Lab operations, GenePath Diagnostics India Private Limited, Pune, Maharashtra, India
| | - Meenal Agarwal
- Chief Clinical Officer, GenePath Diagnostics India Private Limited, Pune, Maharashtra, India
| | - Nikhil Phadke
- Chief Scientific Officer, GenePath Diagnostics India Private Limited, Pune, Maharashtra, India
| | - Anuradha Khadilkar
- Consultant Pediatrician and Deputy Director, Hirabai Cowasji Jehangir medical research Institute, Jehangir Hospital, Pune, Maharashtra, India.
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Dabas A, Bothra M, Kapoor S. CAH Newborn Screening in India: Challenges and Opportunities. Int J Neonatal Screen 2020; 6:E70. [PMID: 33239596 PMCID: PMC7570061 DOI: 10.3390/ijns6030070] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 08/22/2020] [Accepted: 08/25/2020] [Indexed: 01/16/2023] Open
Abstract
Congenital adrenal hyperplasia (CAH) is a common treatable disorder which is associated with life-threatening adrenal crisis, sexual ambiguity, and/or abnormal growth if undiagnosed. Newborn screening is a cost-effective tool to detect affected babies early after birth to optimize their treatment and follow-up. Newborn screening however is in its nascent stage in India where it is not yet introduced universally for all babies. The following review briefly highlights the challenges (e.g., lack of universal screening, healthcare resources) and opportunities (e.g., reduction in morbidity and early correct gender assignment in females) associated with newborn screening for CAH in a large Indian birth cohort.
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Affiliation(s)
| | | | - Seema Kapoor
- Department of Pediatrics, Maulana Azad Medical College and Lok Nayak Hospital, New Delhi 110002, India; (A.D.); (M.B.)
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