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Wang LKP, Shanmugasundaram M, Cooney E, Lee PDK. Siblings with vitamin D-dependent rickets type 1A: Importance of genetic testing and a review of genotype-phenotype correlations. Am J Med Genet A 2024:e63780. [PMID: 38822637 DOI: 10.1002/ajmg.a.63780] [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: 03/12/2024] [Revised: 05/09/2024] [Accepted: 05/18/2024] [Indexed: 06/03/2024]
Abstract
Vitamin D-dependent rickets type 1A (VDDR1A) is a rare condition caused by biallelic pathogenic variants in CYP27B1, which encodes 25-hydroxyvitamin D3-1-α-hydroxylase. Inadequate activity of this enzyme results in deficient 1α-hydroxylation of inactive 25-hydroxyvitamin D to biologically active 1,25-dihydroxyvitamin D, with consequent adverse effects on calcium and phosphate metabolism. A female child was clinically diagnosed at 18 months old with hypophosphatemic rickets based on phenotype and biochemical testing, with neither parent affected. A subsequent affected male sibling led to the reconsideration of the diagnosis. Exome sequencing showed a homozygous CYP27B1 c.1040T>A (p.Ile347Asn) variant for both children. No variants were found in genes associated with hypophosphatemic rickets. A review of published cases of VDDR1A with homozygous CYP27B1 variants indicates variable clinical presentation, lack of genotype-phenotype correlation, and low serum phosphate at diagnosis in most cases. These findings emphasize the clinical importance of molecular testing as part of the diagnostic evaluation for cases of non-nutritional rickets.
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Affiliation(s)
| | | | - Erin Cooney
- Department of Pediatrics, University of Texas Medical Branch, Galveston, Texas, USA
| | - Phillip D K Lee
- Department of Pediatrics, University of Texas Medical Branch, Galveston, Texas, USA
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2
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Jacob P, Bhavani GS, Udupa P, Wang Z, Hariharan SV, Delampady K, Dalal A, Kamath N, Ikegawa S, Shenoy RD, Handattu K, Shah H, Girisha KM. Exome Sequencing in Monogenic Forms of Rickets. Indian J Pediatr 2023; 90:1182-1190. [PMID: 36692815 PMCID: PMC10627992 DOI: 10.1007/s12098-022-04393-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 09/27/2022] [Indexed: 01/25/2023]
Abstract
OBJECTIVE To understand the phenotypic and genotypic spectrum of genetic forms of rickets in 10 families. METHODS Detailed clinical, radiographic, and biochemical evaluation of 10 families with phenotypes suggestive of a genetic cause of rickets was performed. Molecular testing using exome sequencing aided in the diagnosis of six different forms of known genetic causes. RESULTS Eleven disease-causing variants including five previously reported variants (CYP27B1:c.1319_1325dup, p.(Phe443Profs*24), VDR:c.1171C>T, p.(Arg391Cys), PHEX: c.1586_1586+1del, PHEX: c.1482+5G>C, PHEX: c.58C>T, p.(Arg20*)) and six novel variants (CYP27B1:c.974C>T, p.(Thr325Met), CYP27B1: c.1376G>A, p.(Arg459His), CYP2R1: c.595C>T, p.(Arg199*), CYP2R1:c.1330G>C, p.(Gly444Arg),SLC34A3:c.1336-11_1336-1del, SLC2A2: c.589G>C, p.(Val197Leu)) in the genes known to cause monogenic rickets were identified. CONCLUSION The authors hereby report a case series of individuals from India with a molecular diagnosis of rickets and provide the literature review which would help in enhancing the clinical and molecular profile for rapid and differential diagnosis of rickets.
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Affiliation(s)
- Prince Jacob
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Gandham SriLakshmi Bhavani
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Prajna Udupa
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Zheng Wang
- Laboratory for Bone and Joint Diseases, RIKEN Center for Integrative Medical Sciences, Tokyo, Japan
| | - Sankar V Hariharan
- Department of Pediatrics, Genetics Clinic, SAT Hospital, Government Medical College, Thiruvananthapuram, Kerala, India
| | - Kishan Delampady
- Department of Endocrinology, AJ Hospital & Research Center, Mangalore, Karnataka, India
| | - Ashwin Dalal
- Diagnostics Division, Center for DNA Fingerprinting & Diagnostics, Hyderabad, Telangana, India
| | - Nutan Kamath
- Department of Pediatrics, Kasturba Medical College, Mangalore, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Shiro Ikegawa
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, Karnataka, India
- Laboratory for Bone and Joint Diseases, RIKEN Center for Integrative Medical Sciences, Tokyo, Japan
| | - Rathika D Shenoy
- Department of Pediatrics, K S Hegde Medical Academy, Nitte University, Mangalore, Karnataka, India
| | - Koushik Handattu
- Department of Pediatrics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Hitesh Shah
- Department of Pediatric Orthopedics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Katta M Girisha
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, Karnataka, India.
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3
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Méaux MN, Harambat J, Rothenbuhler A, Léger J, Kamenicky P, Soskin S, Boyer O, Boros E, D'Anella P, Mignot B, Gebhart M, Vic P, Richard N, Thivichon-Prince B, Francou B, Linglart A, Bacchetta J, Molin A. Genotype-phenotype Description of Vitamin D-dependent Rickets 1A: CYP27B1 p.(Ala129Thr) Variant Induces a Milder Disease. J Clin Endocrinol Metab 2023; 108:812-826. [PMID: 36321535 DOI: 10.1210/clinem/dgac639] [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: 07/22/2022] [Revised: 10/26/2022] [Indexed: 11/07/2022]
Abstract
INTRODUCTION Vitamin D-dependent rickets type 1A (VDDR1A) is a rare genetic disease associated with loss-of-function variations in the gene encoding the vitamin D-activating enzyme 1α-hydroxylase (CYP27B1). Phenotype-genotype correlation is unclear. Long-term outcome data are lacking. The objective of this study was to describe characteristics and outcomes to search for a phenotype-genotype correlation. METHODS We retrospectively collected clinical data, genetic features, and outcomes from 24 genetically confirmed cases from 10 French centers; results are presented as median (min-max). RESULTS Clinical symptoms at diagnosis (age, 1.5 [0.5-8.7] years) were mainly bone and neurological abnormalities, and laboratory data showed hypocalcemia (1.97 [1.40-2.40] mmol/L), hypophosphatemia (-3.4 [-13.4 to (-)0.2] SD score for age), low 25OHD and low 1,25(OH)2D3, secondary hyperparathyroidism with PTH at 6.6 (1.3-13.7) times the upper limit for normal (ULN; PTH expressed as ULN to homogenize data presentation), and increased alkaline phosphatase (1968 [521-7000] IU/L). Bone radiographs were abnormal in 83% of patients. We identified 17 variations (11 missense, 3 frameshift, 2 truncating, and 1 acceptor splice site variations) in 19 families (homozygous state in 58% [11/19]). The partial loss-of-function variation p.(Ala129Thr) was associated with a milder phenotype: older age at diagnosis, higher serum calcium (2.26 vs 1.85 mmol/L), lower PTH (4.7 vs 7.5 ULN), and lower alkaline phosphatase (759 vs 2082 IU/L). Patients were treated with alfacalcidol. Clinical (skeletal, neurological), biochemical, and radiological outcomes were satisfactory, and complications occurred if there was bad adherence. CONCLUSION Overall, our findings highlight good outcomes under substitutive treatment and the need of a closer follow-up of eyes, teeth, kidneys, and blood pressure in VDDR1A.
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Affiliation(s)
- Marie-Noëlle Méaux
- CHU de Bordeaux, Service de Néphrologie Pédiatrique, Centre de Référence des Maladies Rénales Rares Sorare, 33 000 Bordeaux, France
- CHU de Lyon, Service de Néphrologie, Rhumatologie et Dermatologie Pédiatriques, 69 500 Bron, France
- INSERM, UMR 1033, Faculté de Médecine Lyon Est, Université Claude Bernard Lyon 1, 69 008 Lyon, France
| | - Jérôme Harambat
- CHU de Bordeaux, Service de Néphrologie Pédiatrique, Centre de Référence des Maladies Rénales Rares Sorare, 33 000 Bordeaux, France
| | - Anya Rothenbuhler
- Centre de Référence des Maladies Rares du Calcium et du Phosphate, filière OSCAR, France
- Assistance Publique-Hôpitaux de Paris, Université Paris Saclay, INSERM, Service d'Endocrinologie et Diabète de l'enfant, Unité Physiologie et Physiopathologie Endocrinienne, Hôpital Bicêtre Paris Saclay, 94270 Le Kremlin-Bicêtre, France
| | - Juliane Léger
- Assistance Publique-Hôpitaux de Paris, Hôpital Universitaire Robert Debré, Endocrinologie Diabétologie Pédiatrique, 75 019 Paris, France
| | - Peter Kamenicky
- Assistance Publique-Hôpitaux de Paris, Hôpital Kremlin Bicêtre, Service d'Endocrinologie et de Biologie de la Reproduction, 94270 Le Kremlin-Bicêtre, France
| | - Sylvie Soskin
- CHU de Strasbourg, Service d'Endocrinologie Pédiatrique, 69 091 Strasbourg, France
| | - Olivia Boyer
- Assistance Publique-Hôpitaux de Paris, Hôpital Necker-Enfants Malades, CRMR MARHEA, Institut Imagine, Université Paris Cité, 75015 Paris, France
| | - Emese Boros
- Hôpital Universitaire des enfants Reine Fabiola, Service d'Endocrinologie Pédiatrique, 1020 Bruxelles, Belgique
| | | | - Brigitte Mignot
- CHU de Besançon, Service d'Endocrinologie Pédiatrique, 25000 Besançon, France
| | - Maite Gebhart
- CHU de Besançon, Service d'Endocrinologie Pédiatrique, 25000 Besançon, France
| | - Philippe Vic
- CH de Cornouailles, Service de Pédiatrie, 29000 Quimper, France
| | - Nicolas Richard
- CHU de Caen, Service de Génétique, EA7450 Biotargen, 14033 Caen, France
| | | | - Bruno Francou
- Assistance Publique-Hôpitaux de Paris, Hôpital Kremlin-Bicêtre, Laboratoire de génétique moléculaire, 94270 Le Kremlin-Bicêtre, France
| | - Agnès Linglart
- Centre de Référence des Maladies Rares du Calcium et du Phosphate, filière OSCAR, France
- Assistance Publique-Hôpitaux de Paris, Université Paris Saclay, INSERM, Service d'Endocrinologie et Diabète de l'enfant, Unité Physiologie et Physiopathologie Endocrinienne, Hôpital Bicêtre Paris Saclay, 94270 Le Kremlin-Bicêtre, France
| | - Justine Bacchetta
- CHU de Lyon, Service de Néphrologie, Rhumatologie et Dermatologie Pédiatriques, 69 500 Bron, France
- INSERM, UMR 1033, Faculté de Médecine Lyon Est, Université Claude Bernard Lyon 1, 69 008 Lyon, France
- Centre de Référence des Maladies Rares du Calcium et du Phosphate, filière OSCAR, France
- Centre de Référence des Maladies Rénales Rares Néphrogones, filière ORKID, France
| | - Arnaud Molin
- Centre de Référence des Maladies Rares du Calcium et du Phosphate, filière OSCAR, France
- CHU de Caen, Service de Génétique, EA7450 Biotargen, 14033 Caen, France
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Zamanfar D, Ghazaiean M. An overview of CYP27B1 enzyme mutation and management: A case report and review of the literature. Clin Case Rep 2023; 11:e7007. [PMID: 36879673 PMCID: PMC9984874 DOI: 10.1002/ccr3.7007] [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: 10/06/2022] [Revised: 02/07/2023] [Accepted: 02/13/2023] [Indexed: 03/06/2023] Open
Abstract
Vitamin D-dependent rickets type 1 (VDDRIA) is an autosomal recessive disorder caused by mutations in the Cytochrome P450 Family 27 Subfamily B Member 1 (CYP27B1) gene, which encodes for the enzyme 1 alpha-hydroxylase. We report a known case of VDDRIA with hypotonia, growth and developmental disorders and discuss about the mutation and its management.
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Affiliation(s)
- Daniel Zamanfar
- Pediatric Endocrinologist, Diabetes Research Center of Mazandaran Mazandaran University of Medical Sciences Sari Iran
| | - Mobin Ghazaiean
- Student Research Committee Mazandaran University of Medical Sciences Sari Iran
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5
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Yıldırım R, Ünal E, Tekmenüray A. Evaluation of Clinical Characteristics of Vitamin D Dependent Rickets Type 1 (VDDR-1) Patients and Importance of Early Diagnosis. GÜNCEL PEDIATRI 2022. [DOI: 10.4274/jcp.2022.66564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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6
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Rush ET, Johnson B, Aradhya S, Beltran D, Bristow SL, Eisenbeis S, Guerra NE, Krolczyk S, Miller N, Morales A, Ramesan P, Sarafrazi S, Truty R, Dahir K. Molecular Diagnoses of X-Linked and Other Genetic Hypophosphatemias: Results From a Sponsored Genetic Testing Program. J Bone Miner Res 2022; 37:202-214. [PMID: 34633109 PMCID: PMC9298723 DOI: 10.1002/jbmr.4454] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Revised: 09/27/2021] [Accepted: 10/02/2021] [Indexed: 12/20/2022]
Abstract
X-linked hypophosphatemia (XLH), a dominant disorder caused by pathogenic variants in the PHEX gene, affects both sexes of all ages and results in elevated serum fibroblast growth factor 23 (FGF23) and below-normal serum phosphate. In XLH, rickets, osteomalacia, short stature, and lower limb deformity may be present with muscle pain and/or weakness/fatigue, bone pain, joint pain/stiffness, hearing difficulty, enthesopathy, osteoarthritis, and dental abscesses. Invitae and Ultragenyx collaborated to provide a no-charge sponsored testing program using a 13-gene next-generation sequencing panel to confirm clinical XLH or aid diagnosis of suspected XLH/other genetic hypophosphatemia. Individuals aged ≥6 months with clinical XLH or suspected genetic hypophosphatemia were eligible. Of 831 unrelated individuals tested between February 2019 and June 2020 in this cross-sectional study, 519 (62.5%) individuals had a pathogenic or likely pathogenic variant in PHEX (PHEX-positive). Among the 312 PHEX-negative individuals, 38 received molecular diagnoses in other genes, including ALPL, CYP27B1, ENPP1, and FGF23; the remaining 274 did not have a molecular diagnosis. Among 319 patients with a provider-reported clinical diagnosis of XLH, 88.7% (n = 283) had a reportable PHEX variant; 81.5% (n = 260) were PHEX-positive. The most common variant among PHEX-positive individuals was an allele with both the gain of exons 13-15 and c.*231A>G (3'UTR variant) (n = 66/519). Importantly, over 80% of copy number variants would have been missed by traditional microarray analysis. A positive molecular diagnosis in 41 probands (4.9%; 29 PHEX positive, 12 non-PHEX positive) resulted in at least one family member receiving family testing. Additional clinical or family member information resulted in variant(s) of uncertain significance (VUS) reclassification to pathogenic/likely pathogenic (P/LP) in 48 individuals, highlighting the importance of segregation and clinical data. In one of the largest XLH genetic studies to date, 65 novel PHEX variants were identified and a high XLH diagnostic yield demonstrated broad insight into the genetic basis of XLH. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).
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Affiliation(s)
- Eric T Rush
- Children's Mercy Kansas City, Kansas City, MO, USA.,Department of Pediatrics, University of Missouri - Kansas City School of Medicine, Kansas City, MO, USA.,Department of Internal Medicine, University of Kansas Medical Center, Kansas City, KS, USA
| | | | | | | | | | | | - Norma E Guerra
- Department of Pediatric Nephrology, Hospital General del Centro Médico Nacional «La Raza», Instituto Mexicano del Seguro Social (IMSS), Ciudad de México, Mexico
| | | | | | | | | | | | | | - Kathryn Dahir
- Program for Metabolic Bone Disorders, Vanderbilt University Medical Center (VUMC), Nashville, TN, USA
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7
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Fortin CA, Girard L, Bonenfant C, Leblanc J, Cruz-Marino T, Blackburn ME, Desmeules M, Bouchard L. Benefits of Newborn Screening for Vitamin D-Dependant Rickets Type 1A in a Founder Population. Front Endocrinol (Lausanne) 2022; 13:887371. [PMID: 35600579 PMCID: PMC9120640 DOI: 10.3389/fendo.2022.887371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 03/28/2022] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Vitamin D-dependant rickets type 1A (VDDR1A) is a rare autosomal recessive disorder caused by pathogenic variants in the CYP27B1 gene. This gene is essential for vitamin D activation. Although VDDR1A is a rare condition worldwide, its prevalence is high in the Saguenay-Lac-Saint-Jean (SLSJ) region due to a founder effect. Daily intake of calcitriol before the onset of clinical manifestations can prevent them in affected children. METHODS A genetic screening test was developed and validated for the CYP27B1 gene c.262del pathogenic variant. Newborn screening was implemented in the SLSJ region for this variant, and the feasibility and acceptability were assessed. Sixteen medical records of children affected with VDDR1A were reviewed to document the consequences of the disease at diagnosis. RESULTS A total of 2000 newborns were tested for VDDR1A. Most families (96.5%) accepted the genetic test. We found a carrier rate of 1/29 for the c.262delG variant in our cohort, which is suggestive of a founder effect. We identified one child affected with VDDR1A and treatment was initiated before the onset of clinical manifestations. On average, children with VDDR1A were diagnosed at 13.8 ± 5 months of age, they had a significant failure to thrive at diagnosis, among other harmful health consequences. CONCLUSION Our study showed that in our population, the newborn genetic screening program is safe and feasible, it has high acceptability, and it is efficient to identify affected children. VDDR1A health consequences can be prevented by early initiation of treatment. Therefore, screening programs should be available for populations where it is deemed as beneficial from a public health perspective.
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Affiliation(s)
- Carol-Ann Fortin
- Biochemistry and Functional Genomics Department, Faculty of Medicine and Health Sciences (FMHS), Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Lysanne Girard
- Biochemistry and Functional Genomics Department, Faculty of Medicine and Health Sciences (FMHS), Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Chloé Bonenfant
- Biochemistry and Functional Genomics Department, Faculty of Medicine and Health Sciences (FMHS), Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Josianne Leblanc
- Department of Laboratory Medicine, Centre intégré universitaire de santé et de services sociaux (CIUSSS) du Saguenay-Lac-Saint-Jean – Hôpital de Chicoutimi, Chicoutimi, QC, Canada
| | - Tania Cruz-Marino
- Department of Laboratory Medicine, Centre intégré universitaire de santé et de services sociaux (CIUSSS) du Saguenay-Lac-Saint-Jean – Hôpital de Chicoutimi, Chicoutimi, QC, Canada
| | | | - Mathieu Desmeules
- Medicine Department, FHMS, Université de Sherbrooke, Sherbrooke, QC, Canada
- Clinique des maladies métaboliques, CIUSSS du Saguenay-Lac-Saint-Jean – Hôpital de Chicoutimi, Chicoutimi, QC, Canada
- *Correspondence: Luigi Bouchard, ; Mathieu Desmeules,
| | - Luigi Bouchard
- Biochemistry and Functional Genomics Department, Faculty of Medicine and Health Sciences (FMHS), Université de Sherbrooke, Sherbrooke, QC, Canada
- Department of Laboratory Medicine, Centre intégré universitaire de santé et de services sociaux (CIUSSS) du Saguenay-Lac-Saint-Jean – Hôpital de Chicoutimi, Chicoutimi, QC, Canada
- *Correspondence: Luigi Bouchard, ; Mathieu Desmeules,
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8
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Lin Y, Guan Z, Mei H, Zhang W, Zhou Z, Su L, Cheng J, Zheng R, Liang C, Cai Y, Yin X, Wu D, Liu L, Zeng C. Clinical characteristics and long-term outcomes of 12 children with vitamin D-dependent rickets type 1A: A retrospective study. Front Pediatr 2022; 10:1007219. [PMID: 36405822 PMCID: PMC9671943 DOI: 10.3389/fped.2022.1007219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Accepted: 09/27/2022] [Indexed: 11/06/2022] Open
Abstract
PURPOSE Vitamin D-dependent rickets type 1A (VDDR1A) is a rare autosomal recessive disorder caused by deficiency of the CYP27B1 gene. This study aims to investigate the phenotypic and genotypic features of VDDR1A children in southern China and evaluate the long-term therapeutic effects. METHODS Twelve children from southern China with VDDR1A were enrolled in this study. Their clinical, radiological, biochemical, and molecular findings were analyzed retrospectively. The rickets severity score (RSS), biochemical parameters, and height standard deviation score (HtSDS) were used to evaluate clinical outcomes. RESULTS Six males and six females were included in this VDDR1A cohort. The age of onset was from 6 months to 1.8 years, and the age at diagnosis was 2.1 ± 0.8 years. The most common clinical symptoms at diagnosis were delayed walking (10/12) and severe growth retardation (9/12). HtSDS at diagnosis was negatively associated with age (p < 0.05). All patients presented with hypocalcemia, hypophosphatemia, increased serum alkaline phosphatase and parathyroid hormone, and high RSS at diagnosis. Two allelic variants of the CYP27B1 gene were identified in all patients, including nine different variants, four known and five novel, with c.1319_1325dupCCCACCC(p.Phe443Profs*24) being the most frequent. All patients were treated with calcitriol and calcium after diagnosis, and all patients but one were followed-up from 6 months to 15.6 years. HtSDS, RSS, and biochemical parameters were found to be improved during the first few years of the treatment. However, only five patients had good compliance. Although RSS and biochemical parameters were significantly improved, the HtSDS change was not significant from the time of diagnosis to the last visit, and seven patients remained of a short stature (HtSDS < -2). CONCLUSION Our study extends the mutational spectrum of VDDR1A and finds a hotspot variant of the CYP27B1 gene in southern China. The results reconfirm the importance of early diagnosis and treatment compliance and reveal the challenge of height improvement in VDDR1A patients.
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Affiliation(s)
- Yunting Lin
- Department of Genetics and Endocrinology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, China
| | - Zhihong Guan
- Department of Genetics and Endocrinology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, China
| | - Huifen Mei
- Department of Genetics and Endocrinology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, China
| | - Wen Zhang
- Department of Genetics and Endocrinology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, China
| | - Zhizi Zhou
- Department of Genetics and Endocrinology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, China
| | - Ling Su
- Department of Genetics and Endocrinology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, China
| | - Jing Cheng
- Department of Genetics and Endocrinology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, China
| | - Ruidan Zheng
- Department of Genetics and Endocrinology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, China
| | - Cuili Liang
- Department of Genetics and Endocrinology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, China
| | - Yanna Cai
- Department of Genetics and Endocrinology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, China
| | - Xi Yin
- Department of Genetics and Endocrinology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, China
| | - Dongyan Wu
- Department of Genetics and Endocrinology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, China
| | - Li Liu
- Department of Genetics and Endocrinology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, China
| | - Chunhua Zeng
- Department of Genetics and Endocrinology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, China
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9
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Ozden A, Doneray H. The genetics and clinical manifestations of patients with vitamin D dependent rickets type 1A. J Pediatr Endocrinol Metab 2021; 34:781-789. [PMID: 33823104 DOI: 10.1515/jpem-2020-0691] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Accepted: 02/12/2021] [Indexed: 11/15/2022]
Abstract
OBJECTIVES Vitamin D dependent rickets type 1A (VDDR-1A) is a very rare autosomal recessive disorder caused by mutations in the CYP27B1, which encodes vitamin D 1α-hydroxylase. We report the genetics and clinical manifestations of nine patients with VDDR-1A and compare our patients to other cases with the same mutations in the literature. METHODS The clinical presentations, clinical and laboratory findings and treatment modalities of the patients were evaluated retrospectively. RESULTS The mean age of the patients at the time of diagnosis was 39.9 months (range: 4.5-111). At the time of diagnosis, six patients had received stoss vitamin D therapy. Clinical findings related to rickets were obvious in seven patients and unclear in two patients. Except for one case, all patients had laboratory findings of rickets. A novel variant and four previously reported mutations in CYP27B1 were identified. The mean calcitriol and elemental calcium dose were 45.5 ng/kg/day (range: 20-70) and 75.6 mg/kg/day (range: 45-125), respectively. CONCLUSIONS We found a novel compound heterozygous mutation consisting of a reported duplication [(p.F443Pfs*24 (c.1319_1325 dup CCCACCC)] in exon 8 and a novel deletion [p.D507Efs*34 (c.1521 delC)] in exon 9. Our study suggests that the clinical manifestations and laboratory findings of the patients with VDDR1A are variable even among the patients with the same mutation.
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Affiliation(s)
- Ayse Ozden
- Department of Pediatric Endocrinology, Erzurum Regional Training & Research Hospital, Erzurum, Turkey
| | - Hakan Doneray
- Department of Pediatric Endocrinology, Ataturk University Faculty of Medicine, Erzurum, Turkey
- Clinical Research Development and Design Application and Research Center, Ataturk University, Erzurum, Turkey
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Kaygusuz SB, Alavanda C, Kirkgoz T, Eltan M, Yavas Abali Z, Helvacioglu D, Guran T, Ata P, Bereket A, Turan S. Does Genotype-Phenotype Correlation Exist in Vitamin D-Dependent Rickets Type IA: Report of 13 New Cases and Review of the Literature. Calcif Tissue Int 2021; 108:576-586. [PMID: 33386952 DOI: 10.1007/s00223-020-00784-2] [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: 09/18/2020] [Accepted: 11/28/2020] [Indexed: 11/28/2022]
Abstract
Vitamin D-dependent rickets type IA (VDDR-IA) is caused by biallelic mutations in CYP27B1. Data regarding genotype-phenotype correlation in VDDR-IA are scarce. Here, we aimed to investigate clinical/genotypic features and long-term follow-up of 13 new cases with VDDR-IA and genotype-phenotype correlation of reported cases in the literature. Thirteen patients with VDDR-IA were evaluated. Eight patients had reached their final height at the time of the study and, for whom, long-term outcome data were analyzed. Further, all VDDR-IA patients in the literature (n:183) were analyzed and clinical-genetic features were recorded. The median age of diagnosis was 2.55 ± 1.13 (1.0-12) years. Initial diagnoses before referral to our clinic were nutritional rickets (n:7), hypophosphatemic rickets (n:2), and pseudohypoparathyroidism (n:1). All had biochemical evidence suggestive of VDDR-IA; except one with elevated 1,25(OH)2D3 and another with hyperphosphatemia, in whom pseudohypoparathyroidism was excluded with molecular tests. Combined analyses of our cohort and other series in the literature demonstrated that three most common CYP27B1 mutations are p.F443Pfs*24, c.195 + 2T > G, and p.V88Wfs*71. In Turkish population, p.K192E mutation along with the former two is the most common mutations. Comparison of clinical features demonstrated that c.195 + 2T > G mutation causes the most severe and p.K192E mutation causes the least severe phenotype with respect to age and height at presentation and calcitriol requirement. We found a clear genotype-phenotype correlation in VDDR-IA, notably CYP27B1 intronic c.195 + 2T > G mutation causes a more severe phenotype with lower height SDS at presentation and, higher calcitriol requirement, while less severe phenotype occurs in p.K192E mutation.
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Affiliation(s)
- Sare Betul Kaygusuz
- Department of Pediatric Endocrinology and Diabetes, Marmara University School of Medicine, Istanbul, Turkey
| | - Ceren Alavanda
- Department of Medical Genetics, Marmara University School of Medicine, Istanbul, Turkey
| | - Tarik Kirkgoz
- Department of Pediatric Endocrinology and Diabetes, Marmara University School of Medicine, Istanbul, Turkey
| | - Mehmet Eltan
- Department of Pediatric Endocrinology and Diabetes, Marmara University School of Medicine, Istanbul, Turkey
| | - Zehra Yavas Abali
- Department of Pediatric Endocrinology and Diabetes, Marmara University School of Medicine, Istanbul, Turkey
| | - Didem Helvacioglu
- Department of Pediatric Endocrinology and Diabetes, Marmara University School of Medicine, Istanbul, Turkey
| | - Tulay Guran
- Department of Pediatric Endocrinology and Diabetes, Marmara University School of Medicine, Istanbul, Turkey
| | - Pinar Ata
- Department of Medical Genetics, Marmara University School of Medicine, Istanbul, Turkey
| | - Abdullah Bereket
- Department of Pediatric Endocrinology and Diabetes, Marmara University School of Medicine, Istanbul, Turkey
| | - Serap Turan
- Department of Pediatric Endocrinology and Diabetes, Marmara University School of Medicine, Istanbul, Turkey.
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11
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Zou M, Guven A, BinEssa HA, Al-Rijjal RA, Meyer BF, Alzahrani AS, Shi Y. Molecular Analysis of CYP27B1 Mutations in Vitamin D-Dependent Rickets Type 1A: c.590G > A (p.G197D) Missense Mutation Causes a RNA Splicing Error. Front Genet 2020; 11:607517. [PMID: 33329754 PMCID: PMC7729158 DOI: 10.3389/fgene.2020.607517] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 11/10/2020] [Indexed: 11/22/2022] Open
Abstract
Context Vitamin D-dependent rickets type 1A (VDDR1A) is a rare autosomal recessively inherited disorder due to loss-of-function mutations in the CYP27B1 gene. CYP27B1 encodes an enzyme of 25-hydroxyvitamin D-1α-hydroxylase for converting inactive 25-OHD to biologically active 1,25-(OH)2D. Objective To identify underlying genetic defects in patients with VDDR1A. Methods Twelve patients from 7 Turkish and 2 Saudi families were investigated. The coding exons and intron-exon boundaries of the CYP27B1 gene were amplified by Polymerase Chain Reaction (PCR) from peripheral lymphocyte DNA. PCR products were directly sequenced. The consequences of c.590G > A mutation were analyzed by in silico and functional analysis. Results CYP27B1 mutations were identified in all the patients. Two novel mutations were identified in two separate families: c.171delG (family 7) and c.398_400dupAAT (family 8). The intra-exon deletion of c.171delG resulted in a frameshift and premature stop codon 20 amino acids downstream from the mutation (p.L58Cfs∗20). The intra-exon duplication of c.398_400dupAAT generated a premature stop codon at the mutation site (p.W134∗). A missense c.590G > A (p.G197D) mutation was found in a patient from family 4 and caused a defect in pre-mRNA splicing. As a result, two populations of transcripts were detected: the majority of them with intron 3 retention (83%), and the minority (17%) being properly spliced transcripts with about 16% of wild-type enzymatic activity. The remaining nine patients from six families carried a previously reported c.1319_1325dupCCCACCC (F443Pfs∗24) mutation. Clinically, all the patients need continued calcitriol treatment, which was consistent with inactivation of 25-hydroxy vitamin D1α-hydroxylase activity. Conclusion Two novel frameshift CYP27B1 mutations were identified and predicted to inactivate 25-hydroxyvitamin D-1α-hydroxylase. The loss of enzymatic activity by c.590G > A missense mutation was mainly caused by aberrant pre-mRNA splicing.
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Affiliation(s)
- Minjing Zou
- Department of Genetics, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
| | - Ayla Guven
- Pediatric Endocrinology Clinic, Zeynep Kamil Women and Children Hospital, University of Health Science, Istanbul, Turkey
| | - Huda A BinEssa
- Department of Genetics, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
| | - Roua A Al-Rijjal
- Department of Genetics, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
| | - Brian F Meyer
- Pediatric Endocrinology Clinic, Zeynep Kamil Women and Children Hospital, University of Health Science, Istanbul, Turkey
| | - Ali S Alzahrani
- Department of Medicine, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
| | - Yufei Shi
- Department of Genetics, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
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12
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Li Y, Yuan X, Chen R, Lin X, Shangguan H, Yang X, Zhang Y. Clinical and genetic analysis of two Chinese families with vitamin D-dependent rickets type IA and follow-up. Orphanet J Rare Dis 2020; 15:273. [PMID: 33004071 PMCID: PMC7528464 DOI: 10.1186/s13023-020-01558-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Accepted: 09/23/2020] [Indexed: 12/02/2022] Open
Abstract
Objective Vitamin D-dependent rickets type IA (VDDR-IA) is a rare autosomal recessive disorder characterized by the early onset of severe rickets. The objectives of this study were twofold: (1) to analyze the clinical characteristics and therapy of two patients with VDDR-IA from two separate Chinese families, and (2) investigate the CYP27B1 gene mutations in two large pedigrees. Methods Medical history, clinical manifestations, physical examination, radiological findings and laboratory data were analyzed from two patients with VDDR-IA. Serum 1, 25-dihydroxyvitamin D [1, 25-(OH)2D3] of the two patients and their respective families were measured by ELISA and blood samples from both families was obtained for CYP27B1 gene sequence. Results Two patients had typical manifestations and radiological evidence of rickets. Laboratory data showed hypocalcaemia and hypophosphataemia, along with high levels of serum alkaline phosphatase, parathyroid hormone and 25-hydroxyvitamin D3. However, serum 1,25-(OH)2D3 level were low in the patients but normal in their family members. Genetic sequence identified two patients were homozygous for a duplication mutation in exon 8 of CYP27B1 gene (c.1319_1325dupCCCACCC, p.Phe443Profs * 24). After treating with calcitriol and calcium, there was biochemical improvement with normalization of serum calcium and phosphorus, and radiographic evidence of compensatory skeletal mineralization. One patient developed nephrocalcinosis during follow-up. Conclusions This study identified a recurrent seven-nucleotide insertion of CYP27B1 in two large pedigrees, and compared the clinical characteristics and individual therapy of two affected patients. Additionally, our experience further supports the notion that nephrocalcinosis can occur even on standard doses of calcitriol and oral calcium, and normal level of serum calcium, phosphorus, PTH and 25-(OH)D3.
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Affiliation(s)
- Yunfei Li
- Department of Endocrinology, Genetics and Metabolism, Fuzhou Children's Hospital of Fujian Medical University, No. 145, 817 Middle Road, Fuzhou, 350005, China.,Affiliated Dongfeng General Hospital of Hubei Medical College, Shiyan, 442008, China
| | - Xin Yuan
- Department of Endocrinology, Genetics and Metabolism, Fuzhou Children's Hospital of Fujian Medical University, No. 145, 817 Middle Road, Fuzhou, 350005, China
| | - Ruimin Chen
- Department of Endocrinology, Genetics and Metabolism, Fuzhou Children's Hospital of Fujian Medical University, No. 145, 817 Middle Road, Fuzhou, 350005, China.
| | - Xiangquan Lin
- Department of Endocrinology, Genetics and Metabolism, Fuzhou Children's Hospital of Fujian Medical University, No. 145, 817 Middle Road, Fuzhou, 350005, China
| | - Huakun Shangguan
- Department of Endocrinology, Genetics and Metabolism, Fuzhou Children's Hospital of Fujian Medical University, No. 145, 817 Middle Road, Fuzhou, 350005, China
| | - Xiaohong Yang
- Department of Endocrinology, Genetics and Metabolism, Fuzhou Children's Hospital of Fujian Medical University, No. 145, 817 Middle Road, Fuzhou, 350005, China
| | - Ying Zhang
- Department of Endocrinology, Genetics and Metabolism, Fuzhou Children's Hospital of Fujian Medical University, No. 145, 817 Middle Road, Fuzhou, 350005, China
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Serna J, Bergwitz C. Importance of Dietary Phosphorus for Bone Metabolism and Healthy Aging. Nutrients 2020; 12:E3001. [PMID: 33007883 PMCID: PMC7599912 DOI: 10.3390/nu12103001] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 09/25/2020] [Accepted: 09/26/2020] [Indexed: 12/13/2022] Open
Abstract
Inorganic phosphate (Pi) plays a critical function in many tissues of the body: for example, as part of the hydroxyapatite in the skeleton and as a substrate for ATP synthesis. Pi is the main source of dietary phosphorus. Reduced bioavailability of Pi or excessive losses in the urine causes rickets and osteomalacia. While critical for health in normal amounts, dietary phosphorus is plentiful in the Western diet and is often added to foods as a preservative. This abundance of phosphorus may reduce longevity due to metabolic changes and tissue calcifications. In this review, we examine how dietary phosphorus is absorbed in the gut, current knowledge about Pi sensing, and endocrine regulation of Pi levels. Moreover, we also examine the roles of Pi in different tissues, the consequences of low and high dietary phosphorus in these tissues, and the implications for healthy aging.
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Affiliation(s)
- Juan Serna
- Yale College, Yale University, New Haven, CT 06511, USA;
| | - Clemens Bergwitz
- Section of Endocrinology and Metabolism, Department of Internal Medicine, Yale School of Medicine, New Haven, CT 06519, USA
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14
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BinEssa HA, Zou M, Al-Enezi AF, Alomrani B, Al-Faham MSA, Al-Rijjal RA, Meyer BF, Shi Y. Functional analysis of 22 splice-site mutations in the PHEX, the causative gene in X-linked dominant hypophosphatemic rickets. Bone 2019; 125:186-193. [PMID: 31102713 DOI: 10.1016/j.bone.2019.05.017] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 04/24/2019] [Accepted: 05/13/2019] [Indexed: 12/19/2022]
Abstract
CONTEXT X-linked hypophosphatemic rickets (XLH) is caused by inactivating mutations in the PHEX gene and is the most common form of hereditary rickets. The splice-site mutations account for 17% of all reported PHEX mutations. The functional consequence of these splice-site mutations has not been systemically investigated. OBJECTIVE The current study was undertaken to functionally annotate previously reported 22 splice-site mutations in the PHEX gene. METHODS PHEX mini-genes with different splice-site mutations were created by site-directed mutagenesis and expressed in HEK293 cells. The mRNA transcripts were analyzed by RT-PCR, cloning, and sequencing. RESULTS These splicing mutations led to a variety of consequences, including exon skipping, intron retention, and activation of cryptic splice sites. Among 22 splice-site mutations, exon skipping was the most common event accounting for 73% (16/22). Non-canonical splice-site mutations could result in splicing errors to the same extent as canonical splice-site mutations such as c.436+3G>C, c.436+4A>C, c.436+6T>C, c.437-3C>G, c.850-3C>G, c.1080-3C>A, c.1482+5G>C, c.1586+6T>C, c.1645+5G>A, c.1645+6T>C, c.1701-16T>A, c.1768+5G>A, and c.1899+5G>A. Interestingly, non-canonical (c.436+6T>C and c.1586+6T>C) and canonical splice-site mutations (c.1769-1G>C) could generate partial splicing errors (both wild-type and mutant transcripts were detected), resulting in incomplete inactivation of PHEX gene, which may explain the mild disease phenotype reported previously, providing evidence of genotype-phenotype correlation. c.1645C>T (p.R549*) had no impact on pre-mRNA splicing although it is located next to canonical splice donor site GT. CONCLUSIONS Exon skipping is the most common outcome due to splice-site mutations. Both canonical and non-canonical splice-site mutations can result in either severe or mild RNA splicing defects, contributing to phenotype heterogeneity. Non-canonical splice-site mutations should not be overlooked in genetic screening especially those located within 50 bp from canonical splice site.
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Affiliation(s)
- Huda A BinEssa
- Department of Genetics, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia
| | - Minjing Zou
- Department of Genetics, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia
| | - Anwar F Al-Enezi
- Department of Genetics, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia
| | - Basma Alomrani
- Department of Genetics, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia
| | - Manar S A Al-Faham
- Department of Genetics, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia
| | - Roua A Al-Rijjal
- Department of Genetics, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia
| | - Brian F Meyer
- Department of Genetics, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia
| | - Yufei Shi
- Department of Genetics, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia.
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15
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Kim YM, Jang YY, Jeong JE, Park HJ, Jang JH, Kim JK. A case of vitamin D hydroxylation-deficient rickets type 1A caused by 2 novel pathogenic variants in CYP27B1 gene. Ann Pediatr Endocrinol Metab 2019; 24:137-141. [PMID: 31261480 PMCID: PMC6603605 DOI: 10.6065/apem.2019.24.2.137] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Accepted: 03/11/2019] [Indexed: 11/20/2022] Open
Abstract
Vitamin D hydroxylation-deficient rickets type 1A (VDDR1A, OMIM 264700) is a rare autosomal recessive inherited disorder. Pathogenic variants in the CYP27B1 gene lead to loss of 1α-hydroxylase activity. We report the case of a 22-month-old toddler who presented with growth retardation and delayed development. The patient exhibited the typical laboratory findings of VDDR1A, including hypocalcemia (calcium: 5.2 mg/dL), elevated serum level of alkaline phosphatase (2,600 U/L), elevated serum level of intact-parathyroid hormone (238 pg/mL), low 1,25(OH)2D3 level (11.2 pg/mL), and normal 25(OH)D3 level (40.7 ng/mL). His height and weight were 76.5 cm and 9.5 kg, respectively (both <3rd percentile). The Bayley Scales of Infant and Toddler Development II indicated significantly delayed development (mental development index <50, psychomotor development index <50). The patient was a compound heterozygous for two novel pathogenic variants in the CYP27B1 gene: c.57_69del (p.Glu20Profs*2) and c.171dupG (p.Leu58Alafs*275), inherited from his mother and father, respectively. The patient showed remarkable improvement after treatment with calcitriol and calcium carbonate.
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Affiliation(s)
- You-Min Kim
- Department of Pediatrics, Catholic University of Daegu School of Medicine, Daegu, Korea
| | - Yoon-Young Jang
- Department of Pediatrics, Catholic University of Daegu School of Medicine, Daegu, Korea
| | - Ji-Eun Jeong
- Department of Pediatrics, Catholic University of Daegu School of Medicine, Daegu, Korea
| | - Hye-Jin Park
- Department of Pediatrics, Catholic University of Daegu School of Medicine, Daegu, Korea
| | | | - Jin-Kyung Kim
- Department of Pediatrics, Catholic University of Daegu School of Medicine, Daegu, Korea,Address for correspondence: Jin-Kyung Kim, MD, PhD Department of Pediatrics, Catholic University of Daegu School of Medicine, 33 Duryugongwon-ro 17- gil, Nam-gu, Daegu 42472, Korea Tel: +82-53-650-4240 Fax: +82-53-621-4106 E-mail:
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16
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Dursun F, Özgürhan G, Kırmızıbekmez H, Keskin E, Hacıhamdioğlu B. Genetic and Clinical Characteristics of Patients with Vitamin D Dependent Rickets Type 1A. J Clin Res Pediatr Endocrinol 2019; 11:34-40. [PMID: 30282619 PMCID: PMC6398191 DOI: 10.4274/jcrpe.galenos.2018.2018.0121] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
OBJECTIVE Vitamin D dependent rickets type 1A (VDDR1A) is an autosomal recessive disorder caused by mutations in the 1α-hydroxylase gene (CYB27B1). As it may be confused with nutritional rickets and hypophosphatemic rickets, genetic analysis is important for making a correct diagnosis. METHODS We analysed genomic DNA from 11 patients from eight different Turkish families. The patients were recruited for our studies if they presented with a diagnosis of VDDR. RESULTS The mean ± standard deviation age at diagnosis was 13.1±7.4 months. Seven patients had mild hypocalcemia at presentation while four patients had normal calcium concentrations. All patients underwent CYP27B1 gene analysis. The most prevalent mutation was the c.195 + 2T>G splice donor site mutation, affecting five out of 11 patients with VDDR1A. Two patients from the fourth family were compound heterozygous for c.195 + 2T>G and c.195 + 2 T>A in intron-1. Two patients, from different families, were homozygous for a previously reported duplication mutation in exon 8 (1319_1325dupCCCACCC, Phe443Profs*24). One patient had a homozygous splice site mutation in intron 7 (c.1215 + 2 T>A) and one patient had a homozygous mutation in exon 9 (c.1474 C>T). CONCLUSION Intron-1 mutation was the most common mutation, as previously reported. All patients carrying that mutation were from same city of origin suggesting a “founder” or a “common ancestor” effect. VDDR1A should definitely be considered when a patient with signs of rickets has a normal 25-OHD level or when there is unresponsiveness to vitamin D treatment.
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Affiliation(s)
- Fatma Dursun
- Ümraniye Training and Research Hospital, Clinic of Pediatric Endocrinology, İstanbul, Turkey,* Address for Correspondence: Ümraniye Training and Research Hospital, Clinic of Pediatric Endocrinology, İstanbul, Turkey Phone: +90 505 267 14 03 E-mail:
| | - Gamze Özgürhan
- Süleymaniye Maternity and Children’s Training and Research Hospital, Clinic of Paediatrics, İstanbul, Turkey
| | - Heves Kırmızıbekmez
- Ümraniye Training and Research Hospital, Clinic of Pediatric Endocrinology, İstanbul, Turkey
| | - Ece Keskin
- Süleymaniye Maternity and Children’s Training and Research Hospital, Clinic of Medical Genetic, İstanbul, Turkey
| | - Bülent Hacıhamdioğlu
- İstinye University Faculty of Medicine, Department of Pediatric Endocrinology, İstanbul, Turkey
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17
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Chi Y, Sun J, Pang L, Jiajue R, Jiang Y, Wang O, Li M, Xing X, Hu Y, Zhou X, Meng X, Xia W. Mutation update and long-term outcome after treatment with active vitamin D 3 in Chinese patients with pseudovitamin D-deficiency rickets (PDDR). Osteoporos Int 2019; 30:481-489. [PMID: 30382318 DOI: 10.1007/s00198-018-4607-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2017] [Accepted: 06/15/2018] [Indexed: 01/08/2023]
Abstract
UNLABELLED Pseudovitamin D-deficiency rickets is a rare disease which is caused by CYP27B1. In this study, we identified 9 mutations in 7 PDDR patients. In addition, we observed the response to long-term treatment of calcitriol in 15 Chinese patients with PDDR, which showed that the biochemical abnormalities had been corrected satisfactorily after 1-year treatment. INTRODUCTION Pseudovitamin D-deficiency rickets is a rare autosomal recessive disorder resulting from a defect in 25-hydroxyvitamin D 1α-hydroxylase, which is encoded by CYP27B1. The purpose of this study was to identify the CYP27B1 mutations and investigate the response to long-term treatment of calcitriol in Chinese patients with PDDR. METHODS We investigated CYP27B1 mutations in seven individuals from six separate families. To investigate the response to long-term (13 years) treatment with calcitriol in PDDR patients, we additionally collected clinical data of eight families from our previous report and analyzed their biochemical parameter and radiographic changes during the treatment. RESULTS Nine different mutations were identified: two novel missense mutations (G194R, R259L), three novel and one reported deletion mutations (c1442delA, c1504delA, c311-321del, and c. 48-60del), two novel nonsense mutations (c.85G>T, c.580G>T), and a reported insertion mutation (c1325-1332insCCCACCC). The statistical analysis revealed that parathyroid hormone (PTH) and ALP significantly decreased after 6-month and 1-year treatment with calcitriol respectively. Urine calcium was measured in all the patients without kidney stones being documented. After 6-year treatment, the radiographic abnormalities had also been improved. Two patients who had reached their final height are both with short stature (height Z-score below - 2.0). CONCLUSIONS We identified seven novel mutations of CYP27B1 gene in seven Chinese PDDR families. Our findings revealed after 1-year treatment of active vitamin D3, PTH and ALP significantly decreased. The correction of the biochemical abnormalities had not improved the final height satisfactorily.
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Affiliation(s)
- Y Chi
- Department of Endocrinology, Key Laboratory of Endocrinology, Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan No. 1, Wangfujing, Dongcheng District, Beijing, 100730, China
| | - J Sun
- Department of Endocrinology, Key Laboratory of Endocrinology, Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan No. 1, Wangfujing, Dongcheng District, Beijing, 100730, China
| | - L Pang
- Department of Endocrinology, Key Laboratory of Endocrinology, Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan No. 1, Wangfujing, Dongcheng District, Beijing, 100730, China
| | - R Jiajue
- Department of Endocrinology, Key Laboratory of Endocrinology, Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan No. 1, Wangfujing, Dongcheng District, Beijing, 100730, China
| | - Y Jiang
- Department of Endocrinology, Key Laboratory of Endocrinology, Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan No. 1, Wangfujing, Dongcheng District, Beijing, 100730, China
| | - O Wang
- Department of Endocrinology, Key Laboratory of Endocrinology, Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan No. 1, Wangfujing, Dongcheng District, Beijing, 100730, China
| | - M Li
- Department of Endocrinology, Key Laboratory of Endocrinology, Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan No. 1, Wangfujing, Dongcheng District, Beijing, 100730, China
| | - X Xing
- Department of Endocrinology, Key Laboratory of Endocrinology, Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan No. 1, Wangfujing, Dongcheng District, Beijing, 100730, China
| | - Y Hu
- Department of Endocrinology, Key Laboratory of Endocrinology, Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan No. 1, Wangfujing, Dongcheng District, Beijing, 100730, China
| | - X Zhou
- Department of Endocrinology, Key Laboratory of Endocrinology, Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan No. 1, Wangfujing, Dongcheng District, Beijing, 100730, China
| | - X Meng
- Department of Endocrinology, Key Laboratory of Endocrinology, Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan No. 1, Wangfujing, Dongcheng District, Beijing, 100730, China
| | - W Xia
- Department of Endocrinology, Key Laboratory of Endocrinology, Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan No. 1, Wangfujing, Dongcheng District, Beijing, 100730, China.
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18
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Zendehdel A, Arefi M. Molecular evidence of role of vitamin D deficiency in various extraskeletal diseases. J Cell Biochem 2019; 120:8829-8840. [PMID: 30609168 DOI: 10.1002/jcb.28185] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Accepted: 11/12/2018] [Indexed: 12/19/2022]
Abstract
BACKGROUND Role of vitamin D is not only limited to skeletal system but various other systems of the body, such as immune system, endocrine system, and cardiopulmonary system. MATERIALS AND METHODS It is supported by the confirmations of systems-wide expression of vitamin D receptor (VDR), endocrinal effect of calcitriol, and its role in immune responses. RESULTS Expression of VDR in various systems, immunoregulatory and hormonal response of vitamin D and deficiency of vitamin D may establish various pathologies in the body. CONCLUSION This review provides molecular evidence of relation of vitamin D with extra skeletal.
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Affiliation(s)
- Abolfazl Zendehdel
- Department of Geriatric Medicine, Ziaeian Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Mohammad Arefi
- Department of Clinical Toxicology, School of Medicine, Baharloo Hospital, Tehran University of Medical Sciences, Tehran, Iran
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19
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Michałus I, Rusińska A. Rare, genetically conditioned forms of rickets: Differential diagnosis and advances in diagnostics and treatment. Clin Genet 2018; 94:103-114. [DOI: 10.1111/cge.13229] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2017] [Revised: 02/01/2018] [Accepted: 02/02/2018] [Indexed: 12/21/2022]
Affiliation(s)
- I. Michałus
- Department of Propedeutics Pediatrics and Bone Metabolic Diseases; Medical University of Lodz; Lodz Poland
| | - A. Rusińska
- Department of Propedeutics Pediatrics and Bone Metabolic Diseases; Medical University of Lodz; Lodz Poland
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Abstract
Rickets is a metabolic bone disease that develops as a result of inadequate mineralization of growing bone due to disruption of calcium, phosphorus and/or vitamin D metabolism. Nutritional rickets remains a significant child health problem in developing countries. In addition, several rare genetic causes of rickets have also been described, which can be divided into two groups. The first group consists of genetic disorders of vitamin D biosynthesis and action, such as vitamin D-dependent rickets type 1A (VDDR1A), vitamin D-dependent rickets type 1B (VDDR1B), vitamin D-dependent rickets type 2A (VDDR2A), and vitamin D-dependent rickets type 2B (VDDR2B). The second group involves genetic disorders of excessive renal phosphate loss (hereditary hypophosphatemic rickets) due to impairment in renal tubular phosphate reabsorption as a result of FGF23-related or FGF23-independent causes. In this review, we focus on clinical, laboratory and genetic characteristics of various types of hereditary rickets as well as differential diagnosis and treatment approaches.
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Affiliation(s)
- Sezer Acar
- Dokuz Eylül University Faculty of Medicine, Department of Pediatric Endocrinology, İzmir, Turkey
| | - Korcan Demir
- Dokuz Eylül University Faculty of Medicine, Department of Pediatric Endocrinology, İzmir, Turkey
| | - Yufei Shi
- King Faisal Specialist Hospital & Research Centre, Department of Genetics, Riyadh, Saudi Arabia
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21
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Craniofacial and dental characteristics of patients with vitamin-D-dependent rickets type 1A compared to controls and patients with X-linked hypophosphatemia. Clin Oral Investig 2017; 22:745-755. [PMID: 28608052 DOI: 10.1007/s00784-017-2149-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Accepted: 06/02/2017] [Indexed: 10/19/2022]
Abstract
ᅟOBJECTIVES: Vitamin-D-dependent rickets type 1A (VDDR1A) is a rare inherited disease caused by defective activation of vitamin D. The aim of the study was to describe the craniofacial characteristics and the dental phenotype of patients with genetically confirmed VDDR1A. The VDDR1A findings were compared to findings in patients with X-linked hypophosphatemia (XLH) and healthy controls. MATERIAL AND METHODS Ten patients with VDDR1A were identified. The reference group for the comparison of cephalometric findings was 49 adults without chronic disease. The reference group for the comparison of dental findings was 30 adults with XLH. Clinical examination, clinical photos, and radiographs were obtained. Cephalometric analysis was performed. Photos and radiographs were visually evaluated. RESULTS The depth of the posterior cranial fossa (d-p and d-s-iop) in VDDR1A adults was reduced compared to the reference group (p < 0.05). Five (83%) of six adults with VDDR1A and one (4%) of 25 adults with XLH had enamel hypoplasia on several incisors and/or canines (p < 0.001). Three (75%) of four adults with VDDR1A and none of 16 adults with XLH had several first molars with enamel hypoplasia (p = 0.004). Five of 7 (71%) adults with VDDR1A and 24 of 30 (80%) adults with XLH had endodontically affected teeth. CONCLUSIONS The dental aberration of VDDR1A is more in line with the dental aberration of nutritional rickets than with the dental aberrations in XLH, suggesting the combination of low availability of both calcium and phosphate to be critical in periods of enamel formation. CLINICAL RELEVANCE Knowledge on craniofacial and dental aberration in patients with rare diseases, e.g., inherited rickets, is of importance to the dental practitioner, especially during diagnostics and treatment in special care units.
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Tahir S, Demirbilek H, Ozbek MN, Baran RT, Tanriverdi S, Hussain K. Genotype and Phenotype Characteristics in 22 Patients with Vitamin D-Dependent Rickets Type I. Horm Res Paediatr 2017; 85:309-17. [PMID: 26982175 DOI: 10.1159/000444483] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Accepted: 02/03/2016] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND AND AIMS Vitamin D-dependent rickets type I (VDDR1) is an autosomal recessive disorder caused by mutations in the 25-hydroxyvitamin D 1-alpha-hydroxylase gene (CYP27B1). Mutations in CYP27B1 disrupt or lead to a total loss of the 1-α-hydroxylase activity and require treatment with physiological doses of calcitriol. PATIENTS AND METHODS A genetic analysis of the CYP27B1 gene was conducted in 22 Turkish patients with VDDR1 from 13 families. Presenting characteristics, biochemical features, treatment, and results from the genetic analysis are described. RESULTS A splice donor site mutation c.195 + 2T>G was found in 10 patients. The novel missense p.192K>E (c.574A>G) mutation was detected in 5 patients, and a novel missense p.197G>D (c.590G>A) mutation was found in 4 patients. A previously reported 7-bp duplication 1319-1325dupCCCACCC (Phe443Profs*24) in exon 8 was detected in 1 patient, and 1 patient was a compound heterozygote for the novel p.192K>E and the previously described 1319-1325dupCCCACCC mutations. A novel single base pair deletion, c.171_171delG, leading to a frameshift, was found in 1 patient. CONCLUSIONS We identified 3 novel and 2 previously described mutations in the CYP27B1 gene. A marked phenotypical diversity was observed between families that carried identical mutations, suggesting phenotypical heterogeneity.
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Affiliation(s)
- Sophia Tahir
- Genetics and Epigenetics in Health and Disease, Genetics and Genomic Medicine Programme, UCL Institute of Child Health, Great Ormond Street Hospital for Children, London, UK
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23
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Miller WL. Genetic disorders of Vitamin D biosynthesis and degradation. J Steroid Biochem Mol Biol 2017; 165:101-108. [PMID: 27060335 DOI: 10.1016/j.jsbmb.2016.04.001] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Revised: 04/03/2016] [Accepted: 04/05/2016] [Indexed: 01/10/2023]
Abstract
Vitamin D, an inactive secosteroid pro-hormone, is produced by the action of ultraviolet light on 7-dehydrocholesterol in the skin. The active hormone, 1,25(OH)2D is produced by sequential 25-hydroxylation in the liver, principally by CYP2R1, and 1α-hydroxylation in the kidney by CYP27B1. Mutations in CYP27B1 cause 1α-hydroxylase deficiency, also known as vitamin D dependent rickets type I or hereditary pseudo-vitamin D deficient rickets; very rare mutations in CYP2R1 can cause 25-hydroxylase deficiency. Both deficiencies cause hypocalcemia, secondary hyperparathyroidism, severe rickets in infancy, and low serum concentrations of 1,25(OH)2D; both disorders respond to hormonal replacement therapy with calcitriol. The inactivation of vitamin D is principally initiated by its 23- and 24-hydroxylation by CYP24A1. Mutations in CYP24A1 can cause both severe neonatal hypercalcemia and a less severe adult hypercalcemic syndrome. Other pathways of vitamin D metabolism are under investigation, notably its 20-hydroxylation by the cholesterol side-chain cleavage enzyme, CYP11A1.
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Affiliation(s)
- Walter L Miller
- Center for Reproductive Sciences and Department of Pediatrics, HSE 1634, University of California San Francisco, San Francisco, CA 94143-0556, USA.
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Özcabı B, Tahmiscioğlu Bucak F, Jaferova S, Oruç Ç, Adrovic A, Ceylaner S, Ercan O, Evliyaoğlu O. A Case of Vitamin D-Dependent Rickets Type 1A with a Novel Mutation in the Uzbek Population. J Clin Res Pediatr Endocrinol 2016; 8:484-489. [PMID: 27353739 PMCID: PMC5198011 DOI: 10.4274/jcrpe.3128] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Vitamin D-dependent rickets type 1A (VDDR-1A) (Online Mendelian Inheritance in Man #264700) is a rare, autosomal recessively inherited disorder due to inactivating mutations in CYP27B1. It is characterized by early onset of rickets with hypocalcemia. We aimed to describe the clinical and laboratory findings in a VDDR-1A case and to report a novel homozygote truncating mutation NM_000785.3 c.403C>T (p.Q135*) in CYP27B1 which to our knowledge is the first described mutation in the Uzbek population. The patient was admitted with tetany at the age of 12 months. He was a healthy Uzbek boy until 9 months of age when he had a seizure due to hypocalcemia. Vitamin D treatment was given orally in Turkmenistan (no data available for dose and duration). The patient was the product of a consanguineous marriage. His brother had died with hypocalcemia and pneumonia. At physical examination, anthropometric measurements were within normal limits; he had caput quadratum, enlarged wrists, and carpopedal spasm. Blood calcium, phosphorus, alkaline phosphatase, and parathormone (PTH) levels were 5.9 mg/dL, 3.5 mg/dL, 987 IU/L, and 182.8 pg/mL (12-72), respectively. Radiological findings included cupping and fraying of the radial and ulnar metaphyses. Renal ultrasound revealed nephrocalcinosis (grade 1). Despite high serum PTH and 25-hydroxyvitamin D3 levels, 1,25-dihydroxyvitamin D3 level was low, suggesting a diagnosis of VDDR-1A. The patient was treated with calcium carbonate and calcitriol. DNA sequencing revealed a novel homozygous mutation of NM_000785.3 c.403C>T (p.Q135*) in CYP27B1. VDDR-1A is a rare disorder which needs to be considered even in countries where nutritional vitamin D deficiency is still common.
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Affiliation(s)
- Bahar Özcabı
- İstanbul University Cerrahpaşa Faculty of Medicine, Department of Pediatric Endocrinology, İstanbul, Turkey
| | - Feride Tahmiscioğlu Bucak
- İstanbul University Cerrahpaşa Faculty of Medicine, Department of Pediatric Endocrinology, İstanbul, Turkey
| | - Sevinç Jaferova
- İstanbul University Cerrahpaşa Faculty of Medicine, Department of Pediatric Endocrinology, İstanbul, Turkey
| | - Çiğdem Oruç
- İstanbul University Cerrahpaşa Faculty of Medicine, Department of Pediatric Endocrinology, İstanbul, Turkey
| | - Amra Adrovic
- İstanbul University Cerrahpaşa Faculty of Medicine, Department of Pediatric Endocrinology, İstanbul, Turkey
| | - Serdar Ceylaner
- Intergen Genetic Center and Yüksek İhtisas University Faculty of Medicine, Department of Medical Genetics, Ankara, Turkey
| | - Oya Ercan
- İstanbul University Cerrahpaşa Faculty of Medicine, Department of Pediatric Endocrinology, İstanbul, Turkey
| | - Olcay Evliyaoğlu
- İstanbul University Cerrahpaşa Faculty of Medicine, Department of Pediatric Endocrinology, İstanbul, Turkey, E-mail:
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25
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Zalewski A, Ma NS, Legeza B, Renthal N, Flück CE, Pandey AV. Vitamin D-Dependent Rickets Type 1 Caused by Mutations in CYP27B1 Affecting Protein Interactions With Adrenodoxin. J Clin Endocrinol Metab 2016; 101:3409-18. [PMID: 27399352 DOI: 10.1210/jc.2016-2124] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
CONTEXT CYP27B1 converts 25-hydroxyvitamin D3 to active 1,25-dihydroxyvitamin D3, playing a vital role in calcium homeostasis and bone growth. Vitamin D-dependent rickets type 1 (VDDR-1) is a rare autosomal recessive disorder caused by mutations in CYP27B1. OBJECTIVE The objective of the study was an enzymatic and structural analysis of mutations in a patient with calcipenic rickets. Design, Setting, Patient, and Intervention: Two siblings presented with calcipenic rickets and normal 1,25-dihydroxyvitamin D3 levels. CYP27B1 gene analysis showed compound heterozygous mutations confirming VDDR-1. We studied wild-type CYP27B1 and mutations H441Y and R459L by computational homology modeling, molecular dynamics simulations, and functional studies using a luciferase assay. The patients were successfully treated with calcitriol. MAIN OUTCOME The main outcomes of the study were novel mutations leading to a severe loss of CYP27B1 activities for metabolism of 25-hydroxyvitamin D3. RESULTS Mitochondrial cytochrome P450s require adrenodoxin (FDX1) and adrenodoxin reductase. We created models of CYP27B1-FDX1 complex, which revealed negative effects of mutations H441Y and R459L. Upon structural analysis, near-identical folds, protein contact areas, and orientations of heme/iron-sulfur cluster suggested that both mutations may destabilize the CYP27B1-FDX1 complex by negating directional interactions with adrenodoxin. This system is highly sensitive to small local changes modulating the binding/dissociation of adrenodoxin, and electron-transporting efficiency might change with mutations at the surface. Functional assays confirmed this hypothesis and showed severe loss of activity of CYP27B1 by both mutations. CONCLUSIONS This is the first report of mutations in CYP27B1 causing VDDR-1 by affecting protein-protein interactions with FDX1 that results in reduced CYP27B1 activities. Detailed characterization of mutations in CYP27B1 is required for understanding the novel molecular mechanisms causing VDDR-1.
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Affiliation(s)
- Adam Zalewski
- Division of Pediatric Endocrinology, Diabetology, and Metabolism (A.Z., B.L., C.E.F., A.V.P.), Department of Pediatrics, University Children's Hospital, Inselspital, Bern, and Department of Clinical Research, University of Bern, CH-3010 Bern, Switzerland; and Division of Endocrinology (N.S.M., N.R.), Boston Children's Hospital, and Department of Pediatrics, Harvard Medical School, Boston, Massachusetts 02114
| | - Nina S Ma
- Division of Pediatric Endocrinology, Diabetology, and Metabolism (A.Z., B.L., C.E.F., A.V.P.), Department of Pediatrics, University Children's Hospital, Inselspital, Bern, and Department of Clinical Research, University of Bern, CH-3010 Bern, Switzerland; and Division of Endocrinology (N.S.M., N.R.), Boston Children's Hospital, and Department of Pediatrics, Harvard Medical School, Boston, Massachusetts 02114
| | - Balazs Legeza
- Division of Pediatric Endocrinology, Diabetology, and Metabolism (A.Z., B.L., C.E.F., A.V.P.), Department of Pediatrics, University Children's Hospital, Inselspital, Bern, and Department of Clinical Research, University of Bern, CH-3010 Bern, Switzerland; and Division of Endocrinology (N.S.M., N.R.), Boston Children's Hospital, and Department of Pediatrics, Harvard Medical School, Boston, Massachusetts 02114
| | - Nora Renthal
- Division of Pediatric Endocrinology, Diabetology, and Metabolism (A.Z., B.L., C.E.F., A.V.P.), Department of Pediatrics, University Children's Hospital, Inselspital, Bern, and Department of Clinical Research, University of Bern, CH-3010 Bern, Switzerland; and Division of Endocrinology (N.S.M., N.R.), Boston Children's Hospital, and Department of Pediatrics, Harvard Medical School, Boston, Massachusetts 02114
| | - Christa E Flück
- Division of Pediatric Endocrinology, Diabetology, and Metabolism (A.Z., B.L., C.E.F., A.V.P.), Department of Pediatrics, University Children's Hospital, Inselspital, Bern, and Department of Clinical Research, University of Bern, CH-3010 Bern, Switzerland; and Division of Endocrinology (N.S.M., N.R.), Boston Children's Hospital, and Department of Pediatrics, Harvard Medical School, Boston, Massachusetts 02114
| | - Amit V Pandey
- Division of Pediatric Endocrinology, Diabetology, and Metabolism (A.Z., B.L., C.E.F., A.V.P.), Department of Pediatrics, University Children's Hospital, Inselspital, Bern, and Department of Clinical Research, University of Bern, CH-3010 Bern, Switzerland; and Division of Endocrinology (N.S.M., N.R.), Boston Children's Hospital, and Department of Pediatrics, Harvard Medical School, Boston, Massachusetts 02114
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26
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Koek WNH, Zillikens MC, van der Eerden BCJ, van Leeuwen JPTM. Novel Compound Heterozygous Mutations in the CYP27B1 Gene Lead to Pseudovitamin D-Deficient Rickets. Calcif Tissue Int 2016; 99:326-31. [PMID: 27364341 DOI: 10.1007/s00223-016-0165-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 06/15/2016] [Indexed: 12/01/2022]
Abstract
Pseudovitamin D deficiency is the consequence of a genetic defect in the CYP27B1 gene resulting in diminished or absent conversion of 25-hydroxyvitamin D3 (25-(OH)D3) into 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) and leads to growth retardation and rickets, usually in the first 2 years of life. DNA obtained from human leucocytes from a patient suspected of pseudovitamin D deficiency and her healthy parents was sequenced for a genetic defect in the CYP27B1 gene. In silico analyses on the mutations were performed using online available software. The 1α-hydroxylase activity of the patient, her parents, and a sample derived from a mixed buffy coat of healthy blood donors was measured by culturing peripheral blood mononuclear cells with 25-(OH)D3 and measuring 1,25-(OH)2D3 production. DNA sequencing of the patient suspected of pseudovitamin D deficiency revealed compound heterozygosity in the CYP27B1 gene for a (c413G>T) mutation in exon 3 (R138L) and a (c1232G>A) mutation in exon 8 (C411Y). In silico analyses confirmed that mutations at these positions are probably damaging for the protein since the amino acids are situated in a highly conserved region. In vitro analyses showed a nearly absent 1α-hydroxylase activity in the patient compared to the healthy blood donors. Her healthy parents each of whom carried one of the mutations also had compromised conversion of 25-(OH)D3 into 1,25-(OH)2D3 in peripheral blood mononuclear cells, being only marginally higher than in the patient. We discovered novel compound heterozygous mutations in the CYP27B1 gene in a young girl presenting with pseudovitamin D-deficient rickets, leading to severely decreased 1,25-(OH)2D3 production. Furthermore, both heterozygous parents showed a diminished 1α-hydroxylase activity.
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Affiliation(s)
- W Nadia H Koek
- Department of Internal Medicine, Erasmus MC, Po. Box 2040, 3000 CA, Rotterdam, The Netherlands
| | - M Carola Zillikens
- Department of Internal Medicine, Erasmus MC, Po. Box 2040, 3000 CA, Rotterdam, The Netherlands.
| | - Bram C J van der Eerden
- Department of Internal Medicine, Erasmus MC, Po. Box 2040, 3000 CA, Rotterdam, The Netherlands
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Cho JH, Kang E, Kim GH, Lee BH, Choi JH, Yoo HW. Long-term clinical outcome and the identification of homozygous CYP27B1 gene mutations in a patient with vitamin D hydroxylation-deficient rickets type 1A. Ann Pediatr Endocrinol Metab 2016; 21:169-173. [PMID: 27777911 PMCID: PMC5073165 DOI: 10.6065/apem.2016.21.3.169] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Revised: 07/03/2016] [Accepted: 07/28/2016] [Indexed: 11/20/2022] Open
Abstract
Vitamin D hydroxylation-deficient rickets type 1A (VDDR1A) is an autosomal recessively-inherited disorder caused by mutations in CYP27B1 encoding the 1α-hydroxylase enzyme. We report on a female patient with VDDR1A who presented with hypocalcemic seizure at the age of 13 months. The typical clinical and biochemical features of VDDR1A were found, such as hypocalcemia, increased alkaline phosphatase, secondary hyperparathyroidism and normal 25-hydroxyvitamin D3 (25(OH)D3). Radiographic images of the wrist showed metaphyseal widening with cupping and fraying of the ulna and distal radius, suggesting rickets. A mutation analysis of the CYP27B1 gene identified a homozygous mutation of c.589+1G>A in the splice donor site in intron 3, which was known to be pathogenic. Since that time, the patient has been under calcitriol and calcium treatment, with normal growth and development. During the follow-up period, she did not develop genu valgum, scoliosis, or nephrocalcinosis.
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Affiliation(s)
- Ja Hyang Cho
- Department of Pediatrics, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, Korea
| | - Eungu Kang
- Department of Pediatrics, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, Korea
| | - Gu-Hwan Kim
- Medical Genetics Center, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, Korea
| | - Beom Hee Lee
- Department of Pediatrics, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, Korea
| | - Jin-Ho Choi
- Department of Pediatrics, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, Korea
| | - Han-Wook Yoo
- Department of Pediatrics, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, Korea
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Füchtbauer L, Brusgaard K, Ledaal P, Frost M, Frederiksen AL. Case report: vitamin D-dependent rickets type 1 caused by a novel CYP27B1 mutation. Clin Case Rep 2015; 3:1012-6. [PMID: 26734137 PMCID: PMC4693699 DOI: 10.1002/ccr3.406] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Revised: 08/17/2015] [Accepted: 08/27/2015] [Indexed: 01/31/2023] Open
Abstract
Vitamin D‐dependent rickets type 1 VDDR‐1 is a recessive inherited disorder with impaired activation of vitamin D, caused by mutations in CYP27B1. We present long‐time follow‐up of a case with a novel mutation including high‐resolution peripheral quantitative computed tomography of the bone. Adequate treatment resulted in a normalized phenotype.
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Affiliation(s)
- Laila Füchtbauer
- Department of Endocrinology Sahlgrenska Universitetssjukhuset Gothenburg Sweden
| | - Klaus Brusgaard
- Department of Clinical Genetics Odense University Hospital Odense Denmark
| | - Pål Ledaal
- Pediatric Department Sygehus Sønderjylland Sønderborg Denmark
| | - Morten Frost
- Department of Endocrinology M Odense University Hospital Odense Denmark
| | - Anja L Frederiksen
- Department of Clinical Genetics Odense University Hospital Odense Denmark
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29
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Tomilin V, Mamenko M, Zaika O, Pochynyuk O. Role of renal TRP channels in physiology and pathology. Semin Immunopathol 2015; 38:371-83. [PMID: 26385481 DOI: 10.1007/s00281-015-0527-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Accepted: 09/04/2015] [Indexed: 01/05/2023]
Abstract
Kidneys critically contribute to the maintenance of whole-body homeostasis by governing water and electrolyte balance, controlling extracellular fluid volume, plasma osmolality, and blood pressure. Renal function is regulated by numerous systemic endocrine and local mechanical stimuli. Kidneys possess a complex network of membrane receptors, transporters, and ion channels which allows responding to this wide array of signaling inputs in an integrative manner. Transient receptor potential (TRP) channel family members with diverse modes of activation, varied permeation properties, and capability to integrate multiple downstream signals are pivotal molecular determinants of renal function all along the nephron. This review summarizes experimental data on the role of TRP channels in a healthy mammalian kidney and discusses their involvement in renal pathologies.
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Affiliation(s)
- Viktor Tomilin
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, 6431 Fannin, Houston, TX, 77030, USA.,Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russian Federation
| | - Mykola Mamenko
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, 6431 Fannin, Houston, TX, 77030, USA
| | - Oleg Zaika
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, 6431 Fannin, Houston, TX, 77030, USA
| | - Oleh Pochynyuk
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, 6431 Fannin, Houston, TX, 77030, USA.
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30
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Demir K, Kattan WE, Zou M, Durmaz E, BinEssa H, Nalbantoğlu Ö, Al-Rijjal RA, Meyer B, Özkan B, Shi Y. Novel CYP27B1 Gene Mutations in Patients with Vitamin D-Dependent Rickets Type 1A. PLoS One 2015; 10:e0131376. [PMID: 26132292 PMCID: PMC4489500 DOI: 10.1371/journal.pone.0131376] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Accepted: 05/31/2015] [Indexed: 12/30/2022] Open
Abstract
The CYP27B1 gene encodes 25-hydroxyvitamin D-1α-hydroxylase. Mutations of this gene cause vitamin D-dependent rickets type 1A (VDDR-IA, OMIM 264700), which is a rare autosomal recessive disorder. To investigate CYP27B1 mutations, we studied 8 patients from 7 unrelated families. All coding exons and intron-exon boundaries of CYP27B1 gene were amplified by PCR from peripheral leukocyte DNA and subsequently sequenced. Homozygous mutations in the CYP27B1 gene were found in all the patients and heterozygous mutations were present in their normal parents. One novel single nucleotide variation (SNV, c.1215 T>C, p.R379R in the last nucleotide of exon 7) and three novel mutations were identified:, a splice donor site mutation (c.1215+2T>A) in intron 7, a 16-bp deletion in exon 6 (c.1022-1037del16), and a 2-bp deletion in exon 5 (c.934_935delAC). Both c.1215 T>C and c.1215+2T>A were present together in homozygous form in two unrelated patients, and caused exon 7 skipping. However, c.1215 T>C alone has no effect on pre-mRNA splicing. The skipping of exon 7 resulted in a shift of downstream reading frame and a premature stop codon 57 amino acids from L380 (p.L380Afs*57). The intra-exon deletions of c.1022-1037del16 and c.934_935delAC also resulted in a frameshift and the creation of premature stop codons at p.T341Rfs*5, and p.T312Rfs*19, respectively, leading to the functional inactivation of the CYP27B1 gene. Clinically, all the patients required continued calcitriol treatment and the clinical presentations were consistent with the complete loss of vitamin D1α-hydroxylase activity. In conclusion, three novel mutations have been identified. All of them caused frameshift and truncated proteins. The silent c.1215 T>C SNV has no effect on pre-mRNA splicing and it is likely a novel SNP. The current study further expands the CYP27B1 mutation spectrum.
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Affiliation(s)
- Korcan Demir
- Division of Pediatric Endocrinology, Dr. Behçet Uz Children's Hospital, İzmir, Turkey
| | - Walaa E Kattan
- College of Science and General Studies, Alfaisal University, Riyadh, Saudi Arabia; Department of Genetics, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia
| | - Minjing Zou
- Department of Genetics, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia
| | - Erdem Durmaz
- Department of Pediatric Endocrinology, Sifa University, Bornova Health Application and Research Center, İzmir, Turkey
| | - Huda BinEssa
- Department of Genetics, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia
| | - Özlem Nalbantoğlu
- Division of Pediatric Endocrinology, Dr. Behçet Uz Children's Hospital, İzmir, Turkey
| | - Roua A Al-Rijjal
- Department of Genetics, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia
| | - Brian Meyer
- Department of Genetics, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia
| | - Behzat Özkan
- Division of Pediatric Endocrinology, Dr. Behçet Uz Children's Hospital, İzmir, Turkey
| | - Yufei Shi
- Department of Genetics, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia
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31
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Velásquez-Jones L, Medeiros M, Valverde-Rosas S, Jiménez-Triana C, Del Moral-Espinosa I, Romo-Vázquez JC, Franco-Alvarez I. [Long term follow up of a patient with type I vitamin D-dependent rickets]. BOLETIN MEDICO DEL HOSPITAL INFANTIL DE MEXICO 2015; 72:190-194. [PMID: 29421501 DOI: 10.1016/j.bmhimx.2015.03.008] [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: 03/23/2015] [Accepted: 05/05/2015] [Indexed: 06/08/2023] Open
Abstract
BACKGROUND Vitamin D dependent rickets type I is a rare hereditary disease due to a mutation in CYP27B1 encoding the 1α-hydroxylase gene. Clinically, the condition is characterized by hypocalcemic rickets in early infancy due to a deficit in the production of the vitamin D active metabolite 1,25-dihydroxy-vitamin D3. CASE REPORT We report the case of a patient diagnosed at 11 months with follow-up until 9 years of age. CONCLUSIONS The pathophysiology of the disease and the relevance of early diagnosis and management are discussed.
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Affiliation(s)
- Luis Velásquez-Jones
- Departamento de Nefrología Dr. Gustavo Gordillo Paniagua, Hospital Infantil de México Federico Gómez, México D.F., México
| | - Mara Medeiros
- Laboratorio de Investigación en Nefrología y Metabolismo Mineral Óseo, Hospital Infantil de México Federico Gómez, México D.F., México.
| | - Saúl Valverde-Rosas
- Departamento de Nefrología Dr. Gustavo Gordillo Paniagua, Hospital Infantil de México Federico Gómez, México D.F., México
| | - Clímaco Jiménez-Triana
- Departamento de Nefrología Dr. Gustavo Gordillo Paniagua, Hospital Infantil de México Federico Gómez, México D.F., México
| | - Irma Del Moral-Espinosa
- Departamento de Nefrología Dr. Gustavo Gordillo Paniagua, Hospital Infantil de México Federico Gómez, México D.F., México
| | - José Carlos Romo-Vázquez
- Departamento de Nefrología Dr. Gustavo Gordillo Paniagua, Hospital Infantil de México Federico Gómez, México D.F., México
| | - Isidro Franco-Alvarez
- Departamento de Nefrología Dr. Gustavo Gordillo Paniagua, Hospital Infantil de México Federico Gómez, México D.F., México
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32
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Goltzman D. Inferences from genetically modified mouse models on the skeletal actions of vitamin D. J Steroid Biochem Mol Biol 2015; 148:219-24. [PMID: 25237033 DOI: 10.1016/j.jsbmb.2014.09.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Revised: 08/26/2014] [Accepted: 09/11/2014] [Indexed: 02/04/2023]
Abstract
Vitamin D has pleiotropic extra-skeletal effects which have been noted in mouse models of deletion of either the 25-hydroxy vitamin D 1α-hydroxylase enzyme, cyp27b1 (1OHase(-/-) mice) or of the vitamin D receptor (Vdr(-/-) mice); these may be preventable or reversible by either restoring normal signaling of the 1,25(OH)2D/VDR system, or in some cases by restoring normal mineral homeostasis. However, effects on skeletal and mineral homeostasis are clearly the major phenotype observed in humans with loss-of-function mutations in either CYP27B1 or VDR. In mouse phenocopies of these human disorders, correction of hypocalcemia and hypophosphatemia reduce elevated circulating parathyroid hormone concentrations and normalize impaired bone mineralization, but restoration of normal 1,25(OH)2D/VDR signaling may be required for optimal bone formation. Induction of high endogenous 1,25(OH)2D concentrations in genetically modified mouse models may cause increased bone resorption and decreased mineralization. Transgenic Vdr overexpression and conditional Vdr deletion in cells of the osteoblastic lineage have also provided insights into the stages of osteoblast differentiation which may mediate these actions. These anabolic and catabolic effects of the 1,25(OH)2D system on bone may therefore be a function of both the ambient concentration of circulating 1,25(OH)2D and the stage of differentiation of the osteoblast. This article is part of a Special Issue entitled '17th Vitamin D Workshop'.
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Affiliation(s)
- D Goltzman
- Calcium Research Laboratory, Departments of Medicine and Physiology, McGill University Health Centre, Montreal, Quebec H3A 1A1, Canada.
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33
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Ito N, Peña AS, Perano S, Atkins GJ, Findlay DM, Couper JJ. First Australian report of vitamin D-dependent rickets type I. Med J Aust 2014; 201:420-1. [PMID: 25296067 DOI: 10.5694/mja13.00220] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Accepted: 05/21/2014] [Indexed: 11/17/2022]
Affiliation(s)
- Nobuaki Ito
- Centre for Orthopaedic and Trauma Research, University of Adelaide, Adelaide, SA, Australia.
| | - Alexia S Peña
- Discipline of Paediatrics, University of Adelaide and Robinson Research Institute, Adelaide, SA, Australia
| | - Shiree Perano
- Endocrinology and Diabetes Centre, Women's and Children's Hospital, Adelaide, SA, Australia
| | - Gerald J Atkins
- Centre for Orthopaedic and Trauma Research, University of Adelaide, Adelaide, SA, Australia
| | - David M Findlay
- Centre for Orthopaedic and Trauma Research, University of Adelaide, Adelaide, SA, Australia
| | - Jennifer J Couper
- Discipline of Paediatrics, University of Adelaide and Robinson Research Institute, Adelaide, SA, Australia
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Abstract
Recent studies of inherited disorders of phosphate metabolism have shed new light on the understanding of phosphate metabolism. Phosphate has important functions in the body and several mechanisms have evolved to regulate phosphate balance including vitamin D, parathyroid hormone and phosphatonins such as fibroblast growth factor-23 (FGF23). Disorders of phosphate homeostasis leading to hypo- and hyperphosphataemia are common and have clinical and biochemical consequences. Notably, recent studies have linked hyperphosphataemia with an increased risk of cardiovascular disease. This review outlines the recent advances in the understanding of phosphate homeostasis and describes the causes, investigation and management of hypo- and hyperphosphataemia.
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Affiliation(s)
- P Manghat
- Department of Chemical Pathology, Darent Valley Hospital, Dartford, UK
| | - R Sodi
- Department of Biochemistry, NHS Lanarkshire, East Kilbride, UK
| | - R Swaminathan
- Department of Chemical Pathology, St. Thomas Hospital, London, UK
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35
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No evidence for a role of rareCYP27B1functional variations in multiple sclerosis. Ann Neurol 2013; 73:433-7. [DOI: 10.1002/ana.23834] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Revised: 11/08/2012] [Accepted: 11/28/2012] [Indexed: 01/08/2023]
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