1
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Palagano E, Blair HC, Pangrazio A, Tourkova I, Strina D, Angius A, Cuccuru G, Oppo M, Uva P, Van Hul W, Boudin E, Superti-Furga A, Faletra F, Nocerino A, Ferrari MC, Grappiolo G, Monari M, Montanelli A, Vezzoni P, Villa A, Sobacchi C. Buried in the Middle but Guilty: Intronic Mutations in the TCIRG1 Gene Cause Human Autosomal Recessive Osteopetrosis. J Bone Miner Res 2015; 30:1814-21. [PMID: 25829125 DOI: 10.1002/jbmr.2517] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Revised: 03/16/2015] [Accepted: 03/22/2015] [Indexed: 11/10/2022]
Abstract
Autosomal recessive osteopetrosis (ARO) is a rare genetic bone disease with genotypic and phenotypic heterogeneity, sometimes translating into delayed diagnosis and treatment. In particular, cases of intermediate severity often constitute a diagnostic challenge and represent good candidates for exome sequencing. Here, we describe the tortuous path to identification of the molecular defect in two siblings, in which osteopetrosis diagnosed in early childhood followed a milder course, allowing them to reach the adult age in relatively good conditions with no specific therapy. No clearly pathogenic mutation was identified either with standard amplification and resequencing protocols or with exome sequencing analysis. While evaluating the possible impact of a 3'UTR variant on the TCIRG1 expression, we found a novel single nucleotide change buried in the middle of intron 15 of the TCIRG1 gene, about 150 nucleotides away from the closest canonical splice site. By sequencing a number of independent cDNA clones covering exons 14 to 17, we demonstrated that this mutation reduced splicing efficiency but did not completely abrogate the production of the normal transcript. Prompted by this finding, we sequenced the same genomic region in 33 patients from our unresolved ARO cohort and found three additional novel single nucleotide changes in a similar location and with a predicted disruptive effect on splicing, further confirmed in one of them at the transcript level. Overall, we identified an intronic region in TCIRG1 that seems to be particularly prone to splicing mutations, allowing the production of a small amount of protein sufficient to reduce the severity of the phenotype usually associated with TCIRG1 defects. On this basis, we would recommend including TCIRG1 not only in the molecular work-up of severe infantile osteopetrosis but also in intermediate cases and carefully evaluating the possible effects of intronic changes.
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Affiliation(s)
- Eleonora Palagano
- UOS/IRGB, Milan Unit, National Research Council (CNR), Milan, Italy.,Humanitas Clinical and Research Center, Rozzano, Italy
| | - Harry C Blair
- Veteran's Affairs Medical Center and Department of Pathology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Alessandra Pangrazio
- UOS/IRGB, Milan Unit, National Research Council (CNR), Milan, Italy.,Humanitas Clinical and Research Center, Rozzano, Italy
| | - Irina Tourkova
- Veteran's Affairs Medical Center and Department of Pathology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Dario Strina
- UOS/IRGB, Milan Unit, National Research Council (CNR), Milan, Italy.,Humanitas Clinical and Research Center, Rozzano, Italy
| | - Andrea Angius
- CRS4, Science and Technology Park Polaris, Piscina Manna, Pula, Italy.,Institute of Genetic and Biomedical Research (IRGB), National Research Council (CNR), Monserrato, Italy
| | - Gianmauro Cuccuru
- CRS4, Science and Technology Park Polaris, Piscina Manna, Pula, Italy
| | - Manuela Oppo
- CRS4, Science and Technology Park Polaris, Piscina Manna, Pula, Italy
| | - Paolo Uva
- CRS4, Science and Technology Park Polaris, Piscina Manna, Pula, Italy
| | - Wim Van Hul
- Department of Medical Genetics, University of Antwerp, Antwerp, Belgium
| | - Eveline Boudin
- Department of Medical Genetics, University of Antwerp, Antwerp, Belgium
| | - Andrea Superti-Furga
- Department of Pediatrics, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Flavio Faletra
- Institute for Maternal and Child Health-IRCCS "Burlo Garofolo", Trieste, Italy
| | - Agostino Nocerino
- Clinica Pediatrica, Azienda Ospedaliero-Universitaria "S Maria della Misericordia", Udine, Italy
| | - Matteo C Ferrari
- Hip and Prosthetic Replacement Unit, Humanitas Clinical and Research Center, Rozzano, Italy
| | - Guido Grappiolo
- Hip and Prosthetic Replacement Unit, Humanitas Clinical and Research Center, Rozzano, Italy
| | - Marta Monari
- Clinical Investigation Laboratory, Humanitas Clinical and Research Center, Rozzano, Italy
| | - Alessandro Montanelli
- Clinical Investigation Laboratory, Humanitas Clinical and Research Center, Rozzano, Italy
| | - Paolo Vezzoni
- UOS/IRGB, Milan Unit, National Research Council (CNR), Milan, Italy.,Humanitas Clinical and Research Center, Rozzano, Italy
| | - Anna Villa
- UOS/IRGB, Milan Unit, National Research Council (CNR), Milan, Italy.,Humanitas Clinical and Research Center, Rozzano, Italy
| | - Cristina Sobacchi
- UOS/IRGB, Milan Unit, National Research Council (CNR), Milan, Italy.,Humanitas Clinical and Research Center, Rozzano, Italy
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Sobacchi C, Pangrazio A, Lopez AGM, Gomez DPV, Caldana ME, Susani L, Vezzoni P, Villa A. As little as needed: the extraordinary case of a mild recessive osteopetrosis owing to a novel splicing hypomorphic mutation in the TCIRG1 gene. J Bone Miner Res 2014; 29:1646-50. [PMID: 24535816 PMCID: PMC4258090 DOI: 10.1002/jbmr.2203] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Revised: 01/23/2014] [Accepted: 02/09/2014] [Indexed: 01/22/2023]
Abstract
Mutations in the TCIRG1 gene, coding for a subunit of the osteoclast proton pump, are responsible for more than 50% of cases of human malignant autosomal recessive osteopetrosis (ARO), a rare inherited bone disease with increased bone density owing to a failure in bone resorption. A wide variety of mutations has been described, including missense, nonsense, small deletions/insertions, splice-site mutations, and large genomic deletions, all leading to a similar severe presentation. So far, to the best of our knowledge, no report of a mild phenotype owing to recessive TCIRG1 mutations is present neither in our series of more than 100 TCIRG1-dependent ARO patients nor in the literature. Here we describe an 8-year-old patient referred to us with a clinical diagnosis of ARO, based on radiological findings; of note, no neurological or hematological defects were present in this girl. Surprisingly, we identified a novel nucleotide change in intron 15 of the TCIRG1 gene at the homozygous state, leading to the production of multiple aberrant transcripts, but also, more importantly, of a limited amount of the normal transcript. Our results show that a low level of normal TCIRG1 protein can dampen the clinical presentation of TCIRG1-dependent ARO. On this basis, a small amount of protein might be sufficient to rescue, at least partially, the severe ARO phenotype, and this is particularly important when gene therapy approaches are considered. In addition, we would also recommend that the TCIRG1 gene be included in the molecular diagnosis of mild forms of human ARO.
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Affiliation(s)
- Cristina Sobacchi
- Unitá Operativa di Supporto (UOS)/Institute of Genetic and Biomedical Research (IRGB), Milan Unit, National Research Council (CNR), Milan, Italy; Humanitas Clinical and Research Center, Rozzano, Italy
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3
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Pangrazio A, Puddu A, Oppo M, Valentini M, Zammataro L, Vellodi A, Gener B, Llano-Rivas I, Raza J, Atta I, Vezzoni P, Superti-Furga A, Villa A, Sobacchi C. Exome sequencing identifies CTSK mutations in patients originally diagnosed as intermediate osteopetrosis. Bone 2014; 59:122-6. [PMID: 24269275 PMCID: PMC3885796 DOI: 10.1016/j.bone.2013.11.014] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Revised: 11/04/2013] [Accepted: 11/14/2013] [Indexed: 12/15/2022]
Abstract
Autosomal Recessive Osteopetrosis is a genetic disorder characterized by increased bone density due to lack of resorption by the osteoclasts. Genetic studies have widely unraveled the molecular basis of the most severe forms, while cases of intermediate severity are more difficult to characterize, probably because of a large heterogeneity. Here, we describe the use of exome sequencing in the molecular diagnosis of 2 siblings initially thought to be affected by "intermediate osteopetrosis", which identified a homozygous mutation in the CTSK gene. Prompted by this finding, we tested by Sanger sequencing 25 additional patients addressed to us for recessive osteopetrosis and found CTSK mutations in 4 of them. In retrospect, their clinical and radiographic features were found to be compatible with, but not typical for, Pycnodysostosis. We sought to identify modifier genes that might have played a role in the clinical manifestation of the disease in these patients, but our results were not informative. In conclusion, we underline the difficulties of differential diagnosis in some patients whose clinical appearance does not fit the classical malignant or benign picture and recommend that CTSK gene be included in the molecular diagnosis of high bone density conditions.
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Affiliation(s)
- Alessandra Pangrazio
- UOS/IRGB, Milan Unit, CNR, Milan, Italy; Humanitas Clinical and Research Center, Rozzano, Italy
| | - Alessandro Puddu
- CRS4 Bioinformatics Laboratory, Parco Scientifico e Tecnologico POLARIS, Pula, Italy; IRGB-CNR, Cittadella Universitaria di Monserrato, Cagliari, Italy
| | - Manuela Oppo
- CRS4 Bioinformatics Laboratory, Parco Scientifico e Tecnologico POLARIS, Pula, Italy
| | - Maria Valentini
- CRS4 Bioinformatics Laboratory, Parco Scientifico e Tecnologico POLARIS, Pula, Italy
| | | | - Ashok Vellodi
- Great Ormond Street Children's Hospital, London, United Kingdom
| | - Blanca Gener
- Servicio de Genética, BioCruces Health Research Institute, Hospital Universitario Cruces, Barakaldo, Spain
| | - Isabel Llano-Rivas
- Servicio de Genética, BioCruces Health Research Institute, Hospital Universitario Cruces, Barakaldo, Spain
| | - Jamal Raza
- National Institute of Child Health, Karachi, Pakistan
| | - Irum Atta
- National Institute of Child Health, Karachi, Pakistan
| | - Paolo Vezzoni
- UOS/IRGB, Milan Unit, CNR, Milan, Italy; Humanitas Clinical and Research Center, Rozzano, Italy
| | - Andrea Superti-Furga
- Department of Pediatrics, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Anna Villa
- UOS/IRGB, Milan Unit, CNR, Milan, Italy; Humanitas Clinical and Research Center, Rozzano, Italy
| | - Cristina Sobacchi
- UOS/IRGB, Milan Unit, CNR, Milan, Italy; Humanitas Clinical and Research Center, Rozzano, Italy.
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Pangrazio A, Fasth A, Sbardellati A, Orchard PJ, Kasow KA, Raza J, Albayrak C, Albayrak D, Vanakker OM, De Moerloose B, Vellodi A, Notarangelo LD, Schlack C, Strauss G, Kühl JS, Caldana E, Lo Iacono N, Susani L, Kornak U, Schulz A, Vezzoni P, Villa A, Sobacchi C. SNX10 mutations define a subgroup of human autosomal recessive osteopetrosis with variable clinical severity. J Bone Miner Res 2013; 28:1041-9. [PMID: 23280965 DOI: 10.1002/jbmr.1849] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2012] [Revised: 11/21/2012] [Accepted: 12/05/2012] [Indexed: 11/05/2022]
Abstract
Human Autosomal Recessive Osteopetrosis (ARO) is a genetically heterogeneous disorder caused by reduced bone resorption by osteoclasts. In 2000, we found that mutations in the TCIRG1 gene encoding for a subunit of the proton pump (V-ATPase) are responsible for more than one-half of ARO cases. Since then, five additional genes have been demonstrated to be involved in the pathogenesis of the disease, leaving approximately 25% of cases that could not be associated with a genotype. Very recently, a mutation in the sorting nexin 10 (SNX10) gene, whose product is suggested to interact with the proton pump, has been found in 3 consanguineous families of Palestinian origin, thus adding a new candidate gene in patients not previously classified. Here we report the identification of 9 novel mutations in this gene in 14 ARO patients from 12 unrelated families of different geographic origin. Interestingly, we define the molecular defect in three cases of "Västerbottenian osteopetrosis," named for the Swedish Province where a higher incidence of the disease has been reported. In our cohort of more than 310 patients from all over the world, SNX10-dependent ARO constitutes 4% of the cases, with a frequency comparable to the receptor activator of NF-κB ligand (RANKL), receptor activator of NF-κB (RANK) and osteopetrosis-associated transmembrane protein 1 (OSTM1)-dependent subsets. Although the clinical presentation is relatively variable in severity, bone seems to be the only affected tissue and the defect can be almost completely rescued by hematopoietic stem cell transplantation (HSCT). These results confirm the involvement of the SNX10 gene in human ARO and identify a new subset with a relatively favorable prognosis as compared to TCIRG1-dependent cases. Further analyses will help to better understand the role of SNX10 in osteoclast physiology and verify whether this protein might be considered a new target for selective antiresorptive therapies.
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Affiliation(s)
- Alessandra Pangrazio
- Unità Organizzativa di Supporto/Istituto di Ricerca Genetica e Biomedica, Milan Unit, CNR, Milano, Italy
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5
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Lo Iacono N, Blair HC, Poliani PL, Marrella V, Ficara F, Cassani B, Facchetti F, Fontana E, Guerrini MM, Traggiai E, Schena F, Paulis M, Mantero S, Inforzato A, Valaperta S, Pangrazio A, Crisafulli L, Maina V, Kostenuik P, Vezzoni P, Villa A, Sobacchi C. Osteopetrosis rescue upon RANKL administration to Rankl(-/-) mice: a new therapy for human RANKL-dependent ARO. J Bone Miner Res 2012; 27:2501-10. [PMID: 22836362 DOI: 10.1002/jbmr.1712] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2012] [Revised: 06/15/2012] [Accepted: 07/03/2012] [Indexed: 01/16/2023]
Abstract
In the last decades the molecular basis of monogenic diseases has been largely unraveled, although their treatment has often remained unsatisfactory. Autosomal recessive osteopetrosis (ARO) belongs to the small group of genetic diseases that are usually treated with hematopoietic stem cell transplantation (HSCT). However, this approach is not effective in the recently identified form carrying mutations in the receptor activator of NF-κB ligand (RANKL) gene. In this subset, therapy replacement approach based on RANKL delivery has a strong rationale. Here we demonstrate that the systematic administration of RANKL for 1 month to Rankl(-/-) mice, which closely resemble the human disease, significantly improves the bone phenotype and has beneficial effects on bone marrow, spleen and thymus; major adverse effects arise only when mice are clearly overtreated. Overall, we provide evidence that the pharmacological administration of RANKL represents the appropriate treatment option for RANKL-deficient ARO patients, to be validated in a pilot clinical trial.
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Affiliation(s)
- Nadia Lo Iacono
- UOS/IRGB, Milan Unit, CNR, Milan, Italy; Humanitas Clinical and Research Center, Rozzano, Italy
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6
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Pangrazio A, Caldana ME, Lo Iacono N, Mantero S, Vezzoni P, Villa A, Sobacchi C. Autosomal recessive osteopetrosis: report of 41 novel mutations in the TCIRG1 gene and diagnostic implications. Osteoporos Int 2012; 23:2713-8. [PMID: 22231430 DOI: 10.1007/s00198-011-1878-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Accepted: 11/09/2011] [Indexed: 12/24/2022]
Abstract
UNLABELLED Here we report 41 novel mutations in the TCIRG1 gene that is responsible for the disease in more than 50% of ARO patients. The characterisation of mutations in this gene might be useful in the process of drug design for osteoporosis treatment. INTRODUCTION Autosomal recessive osteopetrosis (ARO) is a genetically heterogeneous disorder due to reduced bone resorption by osteoclasts. In this process, a crucial role is played by the proton pump V-ATPase. Biallelic mutations in the TCIRG1 gene, encoding for the a3 subunit of this pump, are responsible for more than one half of ARO patients. METHODS Patients with a clinical diagnosis of ARO have been collected for 7 years and mutation analysis of the TCIRG1 gene was performed using direct DNA sequencing of PCR-amplified exons according to both a standard protocol and a modified one. RESULTS We report here 41 novel mutations identified in 67 unpublished patients, all with biallelic mutations. In particular, we describe two novel large genomic deletions and two splice site mutations in the 5' UTR of the TCIRG1 gene, in patients previously classified as mono-allelic. CONCLUSIONS Our data highlights the importance of two large genomic deletions and mutations in the 5' UTR with respect to patient management and, more critically, to prenatal diagnosis. With the present work, we strongly contribute to the molecular dissection of TCIRG1-deficient ARO and identify several protein residues which are fundamental for proton pump function and could thus be the target of future drugs designed to inhibit osteoclast resorptive activity.
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Affiliation(s)
- A Pangrazio
- Milan Unit, Institute of Genetic and Biomedical Research (IRGB), National Research Council, 20138, Milan, Italy
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Mégarbané A, Pangrazio A, Villa A, Chouery E, Maarawi J, Sabbagh S, Lefranc G, Sobacchi C. Homozygous stop mutation in the SNX10 gene in a consanguineous Iraqi boy with osteopetrosis and corpus callosum hypoplasia. Eur J Med Genet 2012; 56:32-5. [PMID: 23123320 DOI: 10.1016/j.ejmg.2012.10.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2012] [Accepted: 10/20/2012] [Indexed: 02/07/2023]
Abstract
Recently a mutation in the SNX10 gene that belongs to the sorting nexin family was identified as a cause of a new subset of human autosomal recessive osteopetrosis. Here, we identified a novel homozygous mutation (c.46C > T, p.Arg16X) in SNX10, in an Iraqi boy from a consanguineous family with a history of infantile osteopetrosis. The proband exhibited macrocephaly, prominent forehead, proptosis of the eyes, strabismus, splenomegaly and joint hyperlaxity. Bone X-rays showed increased bone density, metaphyseal under-modelling, transverse alternating bands of greater and lesser density in tubular bones, anteriorly notched vertebral bodies and bone-in-bone appearance. Brain atrophy, external hydrocephalus and thin corpus callosum were noted at the brain MRI and CT scan. Blood test results revealed the presence of anaemia and leukopenia. Our findings confirm the role of SNX10 in autosomal recessive osteopetrosis and help to better define the core set of manifestations associated with this new pathological entity.
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Affiliation(s)
- André Mégarbané
- Unité de Génétique Médicale et laboratoire associé INSERM à l'Unité UMR_S 910, Pôle Technologie Santé, Université Saint-Joseph, Beirut, Lebanon.
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Stark Z, Pangrazio A, McGillivray G, Fink AM. Association of severe autosomal recessive osteopetrosis and structural brain abnormalities: a case report and review of the literature. Eur J Med Genet 2012; 56:36-8. [PMID: 23085203 DOI: 10.1016/j.ejmg.2012.10.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Accepted: 10/01/2012] [Indexed: 01/15/2023]
Abstract
We describe a fetus with severe osteopetrosis diagnosed on post-mortem radiographs following termination of pregnancy at 29 weeks for major brain malformations detected on ultrasound. SNP microarray confirmed loss of heterozygosity in 5% of the genome, consistent with parental consanguinity. Sequencing of the genes known to cause severe recessive osteopetrosis, TCIRG1, CLCN7, OSTM1 and SNX10, was negative. Brain malformations are not typically considered part of the phenotypic spectrum of osteopetrosis. We review the literature, and propose that this may represent a novel autosomal recessive variant of osteopetrosis.
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Affiliation(s)
- Zornitza Stark
- Victorian Clinical Genetics Service, Melbourne, Australia.
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Pangrazio A, Frattini A, Valli R, Maserati E, Susani L, Vezzoni P, Villa A, Al-Herz W, Sobacchi C. A homozygous contiguous gene deletion in chromosome 16p13.3 leads to autosomal recessive osteopetrosis in a Jordanian patient. Calcif Tissue Int 2012; 91:250-4. [PMID: 22847576 DOI: 10.1007/s00223-012-9631-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Accepted: 06/26/2012] [Indexed: 10/28/2022]
Abstract
Human malignant autosomal recessive osteopetrosis (ARO) is a genetically heterogeneous disorder caused by reduced bone resorption by osteoclasts. Mutations in the CLCN7 gene are responsible not only for a substantial portion of ARO patients but also for other forms of osteopetrosis characterized by different severity and inheritance. The lack of a clear genotype/phenotype correlation makes genetic counseling a tricky issue for CLCN7-dependent osteopetrosis. Here, we characterize the first homozygous interstitial deletion in 16p13.3, detected by array comparative genomic hybridization in an ARO patient of Jordanian origin. The deletion involved other genes besides CLCN7, while the proband displayed a classic ARO phenotype; however, her early death did not allow more extensive clinical investigations. The identification of this novel genomic deletion involving a large part of the CLCN7 gene is of clinical relevance, especially in prenatal diagnosis, and suggests the possibility that this kind of mutation has been underestimated so far. These data highlight the need for alternative approaches to genetic analysis also in other ARO-causative genes.
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10
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Pangrazio A, Cassani B, Guerrini MM, Crockett JC, Marrella V, Zammataro L, Strina D, Schulz A, Schlack C, Kornak U, Mellis DJ, Duthie A, Helfrich MH, Durandy A, Moshous D, Vellodi A, Chiesa R, Veys P, Lo Iacono N, Vezzoni P, Fischer A, Villa A, Sobacchi C. RANK-dependent autosomal recessive osteopetrosis: characterization of five new cases with novel mutations. J Bone Miner Res 2012; 27:342-51. [PMID: 22271396 PMCID: PMC3306792 DOI: 10.1002/jbmr.559] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Autosomal recessive osteopetrosis (ARO) is a genetically heterogeneous disorder attributed to reduced bone resorption by osteoclasts. Most human AROs are classified as osteoclast rich, but recently two subsets of osteoclast-poor ARO have been recognized as caused by defects in either TNFSF11 or TNFRSF11A genes, coding the RANKL and RANK proteins, respectively. The RANKL/RANK axis drives osteoclast differentiation and also plays a role in the immune system. In fact, we have recently reported that mutations in the TNFRSF11A gene lead to osteoclast-poor osteopetrosis associated with hypogammaglobulinemia. Here we present the characterization of five additional unpublished patients from four unrelated families in which we found five novel mutations in the TNFRSF11A gene, including two missense and two nonsense mutations and a single-nucleotide insertion. Immunological investigation in three of them showed that the previously described defect in the B cell compartment was present only in some patients and that its severity seemed to increase with age and the progression of the disease. HSCT performed in all five patients almost completely cured the disease even when carried out in late infancy. Hypercalcemia was the most important posttransplant complication. Overall, our results further underline the heterogeneity of human ARO also deriving from the interplay between bone and the immune system, and highlight the prognostic and therapeutic implications of the molecular diagnosis.
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Affiliation(s)
- Alessandra Pangrazio
- Institute of Genetic and Biomedical Research, Milan Unit, National Research Council, Milan, Italy
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11
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Pangrazio A, Boudin E, Piters E, Damante G, Iacono NL, D'Elia AV, Vezzoni P, Van Hul W, Villa A, Sobacchi C. Identification of the first deletion in the LRP5 gene in a patient with autosomal dominant osteopetrosis type I. Bone 2011; 49:568-71. [PMID: 21600326 PMCID: PMC3149657 DOI: 10.1016/j.bone.2011.05.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2011] [Revised: 05/04/2011] [Accepted: 05/04/2011] [Indexed: 10/28/2022]
Abstract
In the last decade, the low-density lipoprotein receptor-related protein 5 (LRP5) gene, coding for a coreceptor in the canonical Wnt signalling pathway, has been shown to play an important role in regulating bone mass and to be involved in the pathogenesis of several bone disorders. Here we describe a patient who presented with a clinical picture of Autosomal Dominant Osteopetrosis type I (ADO I), in whom we could identify the first deletion in the LRP5 gene causing increased bone mass. This mutation caused the in-frame deletion of two amino acids in the fourth blade of the first propeller of the protein, namely the highly conserved glycine at position 171 and the following glutamate residue. In vitro studies suggested that the pathogenic effect of this novel mutation could be due to a decreased inhibition of Wnt signalling by the antagonistic proteins sclerostin and Dickkopf-1, encoded respectively by the SOST and DKK1 genes, in the presence of mutated LRP5. Our results highlight an increasing molecular heterogeneity in LRP5-related bone diseases.
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Affiliation(s)
- Alessandra Pangrazio
- Institute of Genetic and Biomedical Research (IRGB) - Milan Section, National Research Council, 20138 Milan, Italy
- Istituto Clinico Humanitas IRCCS, 20089 Rozzano, Italy
| | - Eveline Boudin
- Department of Medical Genetics, University of Antwerp, 2610 Antwerp, Belgium
| | - Elke Piters
- Department of Medical Genetics, University of Antwerp, 2610 Antwerp, Belgium
| | - Giuseppe Damante
- Azienda Ospedaliero-Universitaria di Udine, Istituto di Genetica, 33100 Udine, Italy
| | - Nadia Lo Iacono
- Institute of Genetic and Biomedical Research (IRGB) - Milan Section, National Research Council, 20138 Milan, Italy
- Istituto Clinico Humanitas IRCCS, 20089 Rozzano, Italy
| | | | - Paolo Vezzoni
- Institute of Genetic and Biomedical Research (IRGB) - Milan Section, National Research Council, 20138 Milan, Italy
- Istituto Clinico Humanitas IRCCS, 20089 Rozzano, Italy
| | - Wim Van Hul
- Department of Medical Genetics, University of Antwerp, 2610 Antwerp, Belgium
| | - Anna Villa
- Institute of Genetic and Biomedical Research (IRGB) - Milan Section, National Research Council, 20138 Milan, Italy
- Istituto Clinico Humanitas IRCCS, 20089 Rozzano, Italy
| | - Cristina Sobacchi
- Institute of Genetic and Biomedical Research (IRGB) - Milan Section, National Research Council, 20138 Milan, Italy
- Istituto Clinico Humanitas IRCCS, 20089 Rozzano, Italy
- Corresponding author at: Istituto Clinico Humanitas IRCCS, via Manzoni 113, 20089 Rozzano (MI), Italy. Fax: + 39 0282245191.
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Pangrazio A, Pusch M, Caldana E, Frattini A, Lanino E, Tamhankar PM, Phadke S, Lopez AGM, Orchard P, Mihci E, Abinun M, Wright M, Vettenranta K, Bariae I, Melis D, Tezcan I, Baumann C, Locatelli F, Zecca M, Horwitz E, Mansour LSB, Van Roij M, Vezzoni P, Villa A, Sobacchi C. Molecular and clinical heterogeneity in CLCN7-dependent osteopetrosis: report of 20 novel mutations. Hum Mutat 2010; 31:E1071-80. [PMID: 19953639 DOI: 10.1002/humu.21167] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The "Osteopetroses" are genetic diseases whose clinical picture is caused by a defect in bone resorption by osteoclasts. Three main forms can be distinguished on the basis of severity, age of onset and means of inheritance: the dominant benign, the intermediate and the recessive severe form. While several genes have been involved in the pathogenesis of the different types of osteopetroses, the CLCN7 gene has drawn the attention of many researchers, as mutations within this gene are associated with very different phenotypes. We report here the characterization of 25 unpublished patients which has resulted in the identification of 20 novel mutations, including 11 missense mutations, 6 causing premature termination, 1 small deletion and 2 putative splice site defects. Careful analysis of clinical and molecular data led us to several conclusions. First, intermediate osteopetrosis is not homogeneous, since it can comprise both severe dominant forms with an early onset and recessive ones without central nervous system involvement. Second, the appropriateness of haematopoietic stem cell transplantation in CLCN7-dependent ARO patients has to be carefully evaluated and exhaustive CNS examination is strongly suggested, as transplantation can almost completely cure the disease in situations where no primary neurological symptoms are present. Finally, the analysis of this largest cohort of CLCN7-dependent ARO patients together with some ADO II families allowed us to draw preliminary genotype-phenotype correlations suggesting that haploinsufficiency is not the mechanism causing ADO II. The availability of biochemical assays to characterize ClC-7 function will help to confirm this hypothesis.
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Affiliation(s)
- Alessandra Pangrazio
- Institute of Biomedical Technologies, National Research Council, 20090 Segrate, Italy
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13
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Villa A, Guerrini MM, Cassani B, Pangrazio A, Sobacchi C. Infantile malignant, autosomal recessive osteopetrosis: the rich and the poor. Calcif Tissue Int 2009; 84:1-12. [PMID: 19082854 DOI: 10.1007/s00223-008-9196-4] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2008] [Accepted: 11/07/2008] [Indexed: 02/06/2023]
Abstract
Human recessive osteopetrosis (ARO) represents a group of diseases in which, due to a defect in osteoclasts, bone resorption is prevented. The deficit could arise either from failure in osteoclast differentiation or from inability to perform resorption by mature, multinucleated, but nonfunctional cells. Historically, osteopetrosis due to both these mechanisms was found in spontaneous and artificially created mouse mutants, but the first five genes identified in human ARO (CA-II, TCIRG1, ClCN7, OSTM1, and PLEKHM1) were all involved in the effector function of mature osteoclasts, being linked to acidification of the cell/bone interface or to intracellular processing of the resorbed material. Differentiation defects in human ARO have only recently been described, following the identification of mutations in both RANKL and RANK, which define a new form of osteoclast-poor ARO, as expected from biochemical, cellular, and animal studies. The molecular dissection of ARO has prognostic and therapeutic implications. RANKL-dependent patients, in particular, represent an interesting subset which could benefit from mesenchymal cell transplant and/or administration of soluble RANKL cytokine.
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Affiliation(s)
- Anna Villa
- Istituto di Tecnologie Biomediche, CNR, via Cervi 93, Segrate, Italy.
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14
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Villa A, Pangrazio A, Caldana E, Guerrini M, Vezzoni P, Frattini A, Sobacchi C. Prognostic potential of precise molecular diagnosis of Autosomal Recessive Osteopetrosis with respect to the outcome of bone marrow transplantation. Cytotechnology 2008; 58:57-62. [PMID: 19002772 DOI: 10.1007/s10616-008-9165-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2008] [Accepted: 09/15/2008] [Indexed: 10/21/2022] Open
Abstract
Hematopoietic stem cell transplantation (HSCT) is often the only practical approach to fatal genetic defects. One of the first pathologies which HSCT was applied to was Autosomal Recessive Osteopetrosis (ARO), a rare genetic bone disease in which a deficit in bone resorption by osteoclasts leads to increased bone density and secondary defects. The disease is often lethal early in life unless treated with HSCT. In utero transplantation (IUT) of the oc/oc mouse, reproducing the clinical features of a subset of ARO, has demonstrated that the quality of life and the survival of transplanted animals are greatly improved, suggesting that a similar protocol could be applied to humans. However, recently the dissection of the molecular bases of the disease has shown that ARO is genetically heterogeneous and has revealed the presence of subsets of patients which do not benefit from HSCT. This observation highlights the importance of molecular diagnosing ARO to identify and establish the proper therapies for a better prognosis. In particular, on the basis of experimental results in murine models, efforts should be undertaken to develop approaches such as IUT and new pharmacological strategies.
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Affiliation(s)
- Anna Villa
- Istituto di Tecnologie Biomediche, CNR, via F.lli Cervi 93, 20090, Segrate, Italy,
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Sobacchi C, Frattini A, Guerrini MM, Abinun M, Pangrazio A, Susani L, Bredius R, Mancini G, Cant A, Bishop N, Grabowski P, Del Fattore A, Messina C, Errigo G, Coxon FP, Scott DI, Teti A, Rogers MJ, Vezzoni P, Villa A, Helfrich MH. Osteoclast-poor human osteopetrosis due to mutations in the gene encoding RANKL. Nat Genet 2007; 39:960-2. [PMID: 17632511 DOI: 10.1038/ng2076] [Citation(s) in RCA: 255] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2007] [Accepted: 05/30/2007] [Indexed: 12/22/2022]
Abstract
Autosomal recessive osteopetrosis is usually associated with normal or elevated numbers of nonfunctional osteoclasts. Here we report mutations in the gene encoding RANKL (receptor activator of nuclear factor-KB ligand) in six individuals with autosomal recessive osteopetrosis whose bone biopsy specimens lacked osteoclasts. These individuals did not show any obvious defects in immunological parameters and could not be cured by hematopoietic stem cell transplantation; however, exogenous RANKL induced formation of functional osteoclasts from their monocytes, suggesting that they could, theoretically, benefit from exogenous RANKL administration.
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Affiliation(s)
- Cristina Sobacchi
- Institute of Biomedical Technologies, Consiglio Nazionale delle Ricerche, via F. Cervi 93, 20090 Segrate, Italy
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Souraty N, Noun P, Djambas-Khayat C, Chouery E, Pangrazio A, Villa A, Lefranc G, Frattini A, Mégarbané A. Molecular study of six families originating from the Middle-East and presenting with autosomal recessive osteopetrosis. Eur J Med Genet 2007; 50:188-99. [PMID: 17400532 DOI: 10.1016/j.ejmg.2007.01.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2006] [Accepted: 01/30/2007] [Indexed: 11/18/2022]
Abstract
Autosomal recessive osteopetrosis is a severe hereditary bone disease whose cellular basis is in the osteoclast, but with heterogeneous molecular defects. We hereby report the clinical and the molecular study of seven patients affected by the recessive form of osteopetrosis (ARO) from six families originating from the Middle-East: four from Lebanon and two from Syria. Parental consanguinity was found in five families. The mean age of diagnosis was 3 months. Failure to thrive, prominent forehead, exophthalmia, optic atrophy, hepatosplenomegaly, neurological manifestations, anaemia, thrombocytopenia, hypocalcaemia, elevated hepatic enzymes and acid phosphatase, and an early fatal outcome were common. Macrocephaly, strabismus, and brain malformations were relatively less common. Mutations were identified in two genes: TCIRG1 and OSTM1. Phenotype-genotype correlation is discussed.
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Affiliation(s)
- Noëlle Souraty
- Unité de Génétique Médicale, Laboratoire de Biologie Moléculaire et Cytogénétique, Faculté de Médecine, Université Saint-Joseph, Beirut, Lebanon
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Pangrazio A, Poliani PL, Megarbane A, Lefranc G, Lanino E, Di Rocco M, Rucci F, Lucchini F, Ravanini M, Facchetti F, Abinun M, Vezzoni P, Villa A, Frattini A. Mutations in OSTM1 (grey lethal) define a particularly severe form of autosomal recessive osteopetrosis with neural involvement. J Bone Miner Res 2006; 21:1098-105. [PMID: 16813530 DOI: 10.1359/jbmr.060403] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
UNLABELLED We report three novel osteopetrosis patients with OSTM1 mutations and review two that have been previously described. Our analysis suggests that OSTM1 defines a new subset of patients with severe central nervous system involvement. This defect is also present in the gl mouse, which could represent a good model to study the role of the gene in the pathogenesis of this disease. INTRODUCTION Autosomal recessive osteopetrosis (ARO) is a severe hereditary bone disease whose cellular basis is in the osteoclast, but with heterogeneous molecular defects. In addition to the TCIRG1 and the ClCN7 genes, whose mutations account for approximately 55% and 10% of cases, respectively, the OSTM1 gene has been described thus far in only two ARO patients. materials and methods: We report here three novel ARO patients presenting with severe primary central nervous system involvement in addition to the classical stigmata of severe bone sclerosis, growth failure, anemia, thrombocytopenia, and visual impairment with optic atrophy. In addition we analyzed the brain morphology and histology of the grey lethal mutant mouse. RESULTS The analysis of the OSTM1 gene in two patients, both from Kuwait, showed homozygous two nucleotide deletion in exon 2, leading to a frameshift and premature termination. The third (Lebanese) patient showed a single point mutation in exon 1, leading to a nonsense mutation. The clinical neurological evaluation of the two Kuwaiti patients by CT and MRI scans showed a defect in the white matter, with a specific diagnosis of severe cerebral atrophy. The gl brain showed a diffuse translucent appearance with loss of the normal demarcation between the white and the grey matter, features consistent with myelin loss or hypomyelination. Histological and myelin staining analysis evidenced an atrophy of the corpus callosum with loss of myelin fibers, and in cortical areas, loss of the normal lamination consistent with multiple foci of cortical dysplasia. CONCLUSIONS These findings suggest that OSTM1-dependent ARO defines a new subset of patients with severe central nervous system involvement leading to a very poor prognosis. The fact that central nervous system involvement is also present in the gl mouse mutant suggests that this mouse is a good model to test possible therapies.
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Frattini A, Blair HC, Sacco MG, Cerisoli F, Faggioli F, Catò EM, Pangrazio A, Musio A, Rucci F, Sobacchi C, Sharrow AC, Kalla SE, Bruzzone MG, Colombo R, Magli MC, Vezzoni P, Villa A. Rescue of ATPa3-deficient murine malignant osteopetrosis by hematopoietic stem cell transplantation in utero. Proc Natl Acad Sci U S A 2005; 102:14629-34. [PMID: 16195375 PMCID: PMC1253616 DOI: 10.1073/pnas.0507637102] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Autosomal recessive osteopetrosis (ARO) is a paradigm for genetic diseases that cause severe, often irreversible, defects before birth. In ARO, osteoclasts cannot remove mineralized cartilage, bone marrow is severely reduced, and bone cannot be remodeled for growth. More than 50% of the patients show defects in the osteoclastic vacuolar-proton-pump subunit, ATP6a3. We treated ATP6a3-deficient mice by in utero heterologous hematopoietic stem cell (HSC) transplant from outbred GFP transgenic mice. Dramatic phenotype rescue by GFP osteoclasts was obtained with engraftment, which was observed in most cases. Engraftment survived for variable periods. Recipients were not immunosuppressed, and graft-versus-host disease was not observed in all pups born after in utero treatment. Thus, differentiation of unmatched HSC transplanted in utero is sufficient to prevent fatal defects in ARO and may prevent complications of ARO unresponsive to conventional bone marrow transplantation. The presence of defective cells is not a barrier to the rescue of the phenotype by donor HSC.
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Affiliation(s)
- Annalisa Frattini
- Human Genome Department, Istituto di Tecnologie Biomediche, Consiglio Nazionale delle Ricerche, 20090 Segrate, Milan, Italy
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Susani L, Pangrazio A, Sobacchi C, Taranta A, Mortier G, Savarirayan R, Villa A, Orchard P, Vezzoni P, Albertini A, Frattini A, Pagani F. TCIRG1-dependent recessive osteopetrosis: mutation analysis, functional identification of the splicing defects, and in vitro rescue by U1 snRNA. Hum Mutat 2005; 24:225-35. [PMID: 15300850 DOI: 10.1002/humu.20076] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Human malignant infantile osteopetrosis (arOP) is a genetically heterogeneous autosomal recessive disorder of bone metabolism. The TCIRG1 gene, encoding the a3 subunit of the vacuolar proton pump, which mediates the acidification of the bone/osteoclast interface, is responsible for more than one-half of the arOP patients. We performed genetic analysis of TCIRG1 in 55 arOP patients including 25 new cases and identified nine novel mutations. The two most frequent mutations, c.1674-1G>A (aberrant splicing: r.1674_1884del) and c.2005C>T (protein variation: p.Arg669X), found in 17 and 16 alleles, respectively, constituted 30% of all TCIRG1 abnormalities. They both originated in Northern Europe, p.Arg669X quite recently from West Flanders, Belgium. As substitutions in splicing regulatory sequences represented a large portion (40%; 44 alleles) of the TCIRG1 variations, we developed a functional splicing assay to distinguish between polymorphic variants and disease-causing mutations. Three intronic nucleotide substitutions flanking the splice sites (c.117+4A>T; c.1673+5G>A; and c.504-8G>A) were studied using hybrid minigenes and an abnormal processing of the transcripts was demonstrated in all cases. Cotransfection experiments with complementary U1 snRNAs performed in c.117+4A>T and c.1673+5G>A mutations showed that only in the first case was the defect at the 5' splice site corrected, indicating that mutations near the invariant GT donor sites are mechanistically different. These findings indicate the feasibility of the hybrid minigene approach to detect splicing defects, particularly in patients in whom the RNA is not available. In addition, the present results suggest that modified U1 snRNAs may represent a new therapeutic strategy for arOP patients with a U1 snRNP-dependent splicing defect.
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Affiliation(s)
- Lucia Susani
- Istituto di Tecnologie Biomediche, CNR, Milan, Italy
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20
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Frattini A, Pangrazio A, Susani L, Sobacchi C, Mirolo M, Abinun M, Andolina M, Flanagan A, Horwitz EM, Mihci E, Notarangelo LD, Ramenghi U, Teti A, Van Hove J, Vujic D, Young T, Albertini A, Orchard PJ, Vezzoni P, Villa A. Chloride channel ClCN7 mutations are responsible for severe recessive, dominant, and intermediate osteopetrosis. J Bone Miner Res 2003; 18:1740-7. [PMID: 14584882 DOI: 10.1359/jbmr.2003.18.10.1740] [Citation(s) in RCA: 186] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
UNLABELLED Among 94 osteopetrotic patients presenting with a severe clinical picture and diagnosed early in life, 12 bore mutations in the ClCN7 gene, but only 7 of them had the expected two recessive mutations. The remaining five patients seem to be heterozygous for a ClCN7 mutation, and significant variations were observed in the clinical manifestations of their disease, even within the same family. INTRODUCTION Human osteopetroses are a heterogeneous group of diseases that include both infantile severe, autosomal recessive (ARO) and adult autosomal dominant (ADO) forms. Two genes, Atp6a3 (TCIRG1) and ClCN7, have been shown to be associated with human ARO, the latter of which is also thought to be responsible for ADO-II. However, patients with an intermediate phenotype have been described: the genetic basis of these observances is unknown. MATERIALS AND METHODS In this study, we report the clinical and molecular analysis of 94 patients in which a diagnosis of severe osteopetrosis was made within the first 2 years of age. Both TCIRG1 and CLCN7 genes were sequenced in all patients and the molecular findings were correlated to clinical parameters. RESULTS AND CONCLUSIONS In 56 of 94 patients with a classical picture of ARO, TCIRG1-dependent recessive mutations were found. In contrast, ClCN7 mutations were found in 12 cases (13%) of severe osteopetrosis, but only 7 of them had two recessive mutations identified: in 6 of these 7 cases, central nervous system manifestations were noted, and these patients had a poor prognosis. The remaining five cases were heterozygous for a ClCN7 mutation, including two brothers from a large family with a history of ADO-II in which the presence of a second ClCN7 mutation was formally excluded. Despite an early and severe clinical presentation, these five patients all reached adulthood, suggesting that the degree of dominant interference with chloride channel function can vary widely. Our findings suggest that recessive ClCN7-dependent ARO may be associated with CNS involvement and have a very poor prognosis, whereas heterozygous ClCN7 mutations cause a wide range of phenotypes even in the same family, ranging from early severe to nearly asymptomatic forms. These findings have prognostic implications, might complicate prenatal diagnosis of human osteopetroses, and could be relevant to the management of these patients.
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Scozzari R, Cruciani F, Pangrazio A, Santolamazza P, Vona G, Moral P, Latini V, Varesi L, Memmi MM, Romano V, De Leo G, Gennarelli M, Jaruzelska J, Villems R, Parik J, Macaulay V, Torroni A. Human Y-chromosome variation in the western Mediterranean area: implications for the peopling of the region. Hum Immunol 2001; 62:871-84. [PMID: 11543889 DOI: 10.1016/s0198-8859(01)00286-5] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Y-chromosome variation was analyzed in a sample of 1127 males from the Western Mediterranean area by surveying 16 biallelic and 4 multiallelic sites. Some populations from Northeastern Europe and the Middle East were also studied for comparison. All Y-chromosome haplotypes were included in a parsimonious genealogic tree consisting of 17 haplogroups, several of which displayed distinct geographic specificities. One of the haplogroups, HG9.2, has some features that are compatible with a spread into Europe from the Near East during the Neolithic period. However, the current distribution of this haplogroup would suggest that the Neolithic gene pool had a major impact in the eastern and central part of the Mediterranean basin, but very limited consequences in Iberia and Northwestern Europe. Two other haplogroups, HG25.2 and HG2.2, were found to have much more restricted geographic distributions. The first most likely originated in the Berbers within the last few thousand years, and allows the detection of gene flow to Iberia and Southern Europe. The latter haplogroup is common only in Sardinia, which confirms the genetic peculiarity and isolation of the Sardinians. Overall, this study demonstrates that the dissection of Y-chromosome variation into haplogroups with a more restricted geographic distribution can reveal important differences even between populations that live at short distances, and provides new clues to their past interactions.
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Affiliation(s)
- R Scozzari
- Department of Genetics and Molecular Biology, University of Rome "La Sapienza,", Rome, Italy.
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Malaspina P, Cruciani F, Santolamazza P, Torroni A, Pangrazio A, Akar N, Bakalli V, Brdicka R, Jaruzelska J, Kozlov A, Malyarchuk B, Mehdi SQ, Michalodimitrakis E, Varesi L, Memmi MM, Vona G, Villems R, Parik J, Romano V, Stefan M, Stenico M, Terrenato L, Novelletto A, Scozzari R. Patterns of male-specific inter-population divergence in Europe, West Asia and North Africa. Ann Hum Genet 2000; 64:395-412. [PMID: 11281278 DOI: 10.1046/j.1469-1809.2000.6450395.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We typed 1801 males from 55 locations for the Y-specific binary markers YAP, DYZ3, SRY10831 and the (CA)n microsatellites YCAII and DYS413. Phylogenetic relationships of chromosomes with the same binary haplotype were condensed in seven large one-step networks, which accounted for 95% of all chromosomes. Their coalescence ages were estimated based on microsatellite diversity. The three largest and oldest networks undergo sharp frequency changes in three areas. The more recent network 3.1A clearly discriminates between Western and Eastern European populations. Pairwise Fst showed an overall increment with increasing geographic distance but with a slope greatly reduced when compared to previous reports. By sectioning the entire data set according to geographic and linguistic criteria, we found higher Fst-on-distance slopes within Europe than in West Asia or across the two continents.
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Affiliation(s)
- P Malaspina
- Department of Biology, University of Rome Tor Vergata, Italy.
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