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Abstract
Heimler syndrome is a rare syndrome associating sensorineural hearing loss with retinal dystrophy and amelogenesis imperfecta due to PEX1 or PEX6 biallelic pathogenic variations. This syndrome is one of the less severe forms of peroxisome biogenesis disorders. In this chapter, we will review clinical, biological, and genetic knowledges about the Heimler syndrome.
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Affiliation(s)
- S Mechaussier
- Laboratory of Genetics in Ophthalmology (LGO), INSERM UMR1163, Institute of Genetic Diseases, Imagine and Paris University, Paris, France
| | - I Perrault
- Laboratory of Genetics in Ophthalmology (LGO), INSERM UMR1163, Institute of Genetic Diseases, Imagine and Paris University, Paris, France
| | - H Dollfus
- Department of Medical Genetics, Institute of Medical Genetics of Alsace (IGMA), Strasbourg University Hospitals - Hautepierre Hospital, Strasbourg, France.,Laboratory of Medical Genetics, INSERM U1112, Institute of Medical Genetics of Alsace (IGMA), Strasbourg University, Strasbourg, France
| | - A Bloch-Zupan
- Strasbourg University, Faculty of Dental Medicine, Institute for Advanced Study (USIAS), Strasbourg, France.,Strasbourg University Hospitals (HUS), Oral Surgery and Oral Medecine Unit, Dental Clinic, Civil Hospital, Reference Center for Rare Oral and Dental Diseases, O-Rares, Filière Santé Maladies rares TETE COU, European Reference Network ERN CRANIO, Strasbourg, France.,Strasbourg University, Institute of Genetics and Molecular and Cellular Biology (IGBMC), Illkirch, France
| | - N Loundon
- Pediatric ENT Department, Necker-Enfants Malades Hospital, Paris, France.,Reference Center for Rare Diseases "Genetic deafness", Filière Santé Maladies rares SENSGENE, European Reference Network ERN CRANIO, Federation of Genetic, Necker-Enfants Malades Hospital, Paris, France
| | - L Jonard
- Reference Center for Rare Diseases "Genetic deafness", Filière Santé Maladies rares SENSGENE, European Reference Network ERN CRANIO, Federation of Genetic, Necker-Enfants Malades Hospital, Paris, France
| | - S Marlin
- Reference Center for Rare Diseases "Genetic deafness", Filière Santé Maladies rares SENSGENE, European Reference Network ERN CRANIO, Federation of Genetic, Necker-Enfants Malades Hospital, Paris, France. .,Laboratory of Embryology and Genetics of Malformations, INSERM UMR 1163, Institute of Genetic Diseases, Imagine and Paris University, Paris, France.
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Perrault I, Halbritter J, Porath J, Gerard X, Braun D, Gee H, Fathy H, Saunier S, Cormier-Daire V, Thomas S, Attié-Bitach T, Boddaert N, Taschner M, Schueler M, Lorentzen E, Lifton R, Otto E, Bastin P, Kaplan J, Hildebrandt F, Rozet JM. Mutations of IFT81, encoding an IFT-B core protein, as a rare cause of a ciliopathy. Cilia 2015. [PMCID: PMC4519174 DOI: 10.1186/2046-2530-4-s1-p7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Perrault I, Hanein S, Nicouleau M, Saunier S, Bole C, Nitschké P, Xerri O, Delphin N, Munnich A, Kaplan J, Rozet JM. Ciliome resequencing: A lifeline for molecular diagnosis in LCA. Cilia 2015. [PMCID: PMC4519145 DOI: 10.1186/2046-2530-4-s1-p55] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Saunier S, Bizet AA, Silbermann F, Filhol E, Blisnick T, Henneveu A, Montenont E, Perrault I, Boyle-Feysot C, Rozet JM, Bastin P, Arts HH, Antignac C, Benmerah AR. Alteration of nephrocystins and IFT-A proteins causes similar ciliary phenotypes leading to Nephronophthisis. Cilia 2012. [PMCID: PMC3555870 DOI: 10.1186/2046-2530-1-s1-p99] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Perrault I, Saunier S, Hanein S, Filhol E, Bizet A, Collins F, Salih M, Silva E, Baudouin V, Oud M, Shannon N, Le Merrer M, Pietrement C, Beales P, Arts H, Munnich A, Kaplan J, Antignac C, Cormier Daire V, Rozet JM. Mainzer-Saldino syndrome is a ciliopathy caused by mutations in the IFT140 gene. Cilia 2012. [PMCID: PMC3555764 DOI: 10.1186/2046-2530-1-s1-o28] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Perrault I, Rozet JM, Munnich A, Kaplan J. Des mutations retrouvées pour la première fois dans une guanylyl cyclase (RetGC) responsables d'une cécité néo-natale : l'amaurose congénitale de Leber. ACTA ACUST UNITED AC 2012. [DOI: 10.4267/10608/416] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Papon JF, Perrault I, Coste A, Louis B, Gérard X, Hanein S, Fares-Taie L, Gerber S, Defoort-Dhellemmes S, Vojtek AM, Kaplan J, Rozet JM, Escudier E. Abnormal respiratory cilia in non-syndromic Leber congenital amaurosis with CEP290 mutations. J Med Genet 2010; 47:829-34. [PMID: 20805370 DOI: 10.1136/jmg.2010.077883] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND Leber congenital amaurosis (LCA) is the earliest and most severe inherited retinal degeneration. Isolated forms of LCA frequently result from mutation of the CEP290 gene which is expressed in various ciliated tissues. METHODS Seven LCA patients with CEP290 mutations were investigated to study otorhinolaryngologic phenotype and respiratory cilia. Nasal biopsies and brushing were performed to study cilia ultrastructure using transmission electron microscopy and ciliary beating using high-speed videomicroscopy, respectively. CEP290 expression in normal nasal epithelium was studied using real-time RT-PCR. RESULTS When electron microscopy was feasible (5/7), high levels of respiratory cilia defects were detected. The main defects concerned dynein arms, central complex and/or peripheral microtubules. All patients had a rarefaction of ciliated cells and a variable proportion of short cilia. Frequent but moderate and heterogeneous clinical and ciliary beating abnormalities were found. CEP290 was highly expressed in the neural retina and nasal epithelial cells compared with other tissues. DISCUSSION These data provide the first clear demonstration of respiratory cilia ultrastructural defects in LCA patients with CEP290 mutations. The frequency of these findings in LCA patients along with the high expression of CEP290 in nasal epithelium suggest that CEP290 has an important role in the proper development of both the respiratory ciliary structures and the connecting cilia of photoreceptors. The presence of respiratory symptoms in patients could represent additional clinical criteria to direct CEP290 genotyping of patients affected with the genetically heterogeneous cone-rod dystrophy subtype of LCA.
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Aboussair N, Berahou A, Perrault I, Elalaoui SC, Megzari A, Rozet JM, Kaplan J, Sefiani A. [First North African observation of Leber congenital amaurosis secondary to CEP290 gene mutation]. J Fr Ophtalmol 2010; 33:117.e1-5. [PMID: 20056295 DOI: 10.1016/j.jfo.2009.11.009] [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: 01/23/2009] [Accepted: 04/13/2009] [Indexed: 01/24/2023]
Abstract
Leber congenital amaurosis (LCA) is a the earliest and most severe form of retinal dystrophy responsible for congenital blindness. LCA has genetic heterogeneity and the study of this disease is elucidating the genetics and molecular interactions involved in the development of the retina. To date, 11 LCA genes have been mapped, ten of which have been identified. The CEP290 gene has been shown to account for Joubert and Senior-Loken syndromes and to be a frequent cause of nonsyndromic LCA. We report here the first Arab patient, born to consanguineous parents, with Leber congenital amaurosis attributable to mutation of the CEP290 gene.
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Affiliation(s)
- N Aboussair
- Département de Génétique Médicale, Institut National d'Hygiène, Rabat, Maroc.
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Barbet F, Hakiki S, Orssaud C, Gerber S, Perrault I, Hanein S, Ducroq D, Dufier JL, Munnich A, Kaplan J, Rozet JM. A third locus for dominant optic atrophy on chromosome 22q. J Med Genet 2006; 42:e1. [PMID: 15635063 PMCID: PMC1735912 DOI: 10.1136/jmg.2004.025502] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Hanein S, Perrault I, Gerber S, Tanguy G, Hamel C, Dufier JL, Rozet JM, Kaplan J. [Leber congenital amaurosis: comprehensive survey of genetic heterogeneity. A clinical definition update]. J Fr Ophtalmol 2005; 28:98-105. [PMID: 15767905 DOI: 10.1016/s0181-5512(05)81031-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [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: 10/22/2022]
Abstract
Leber congenital amaurosis (LCA) is the earliest and most severe form of all inherited retinal dystrophies, responsible for congenital blindness. Disease-associated mutations have been hitherto reported in seven genes. These genes are all expressed preferentially in the photoreceptor cells or the retinal pigment epithelium, but they are involved in strikingly different physiologic pathways, resulting in an unforeseeable pathophysiologic variety. This broad genetic and physiologic heterogeneity, which could greatly increase in the coming years, hinders molecular diagnosis in LCA patients. Genotyping is, however, required to establish genetically defined subgroups of patients ready for therapy. Here we report a comprehensive mutational analysis of all the known genes in 179 unrelated LCA patients, including 52 familial and 127 sporadic (27/127 consanguineous) cases. Mutations were identified in 47.5% of patients. GUCY2D accounted for by far the largest part of the LCA cases in our series (21.2%), followed by CRB1 (10%), RPE65 (6.1%), RPGRIP1 (4.5%), AIPL1 (3.4%), TULP1 (1.7%) and CRX (0.6%). The clinical history of all patients with mutations was carefully revisited in the search for phenotype variations. Genotype-phenotype correlations were found that made it possible to divide patients into two main groups. The first one includes patients whose symptoms fit the traditional definition of LCA, i.e., congenital or very early cone-rod dystrophy, while the second group gathers patients affected with severe yet progressive rod-cone dystrophy. In addition, objective ophthalmologic data subdivided each group into two subtypes. Based on these findings, we have drawn decisional flowcharts directing the molecular analysis of LCA genes in a given case. These flowcharts will hopefully lighten the onerous task of genotyping new patients, but only if the most precise clinical history since birth is available.
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Affiliation(s)
- S Hanein
- Unité de Recherche sur les Handicaps Génétiques de l'Enfant, INSERM U 393, Hôpital Necker-Enfants Malades, Paris, France
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Perrault I, Hanein S, Gerber S, Barbet F, Dufier JL, Munnich A, Rozet JM, Kaplan J. Evidence of autosomal dominant Leber congenital amaurosis (LCA) underlain by a CRX heterozygous null allele. J Med Genet 2003; 40:e90. [PMID: 12843339 PMCID: PMC1735514 DOI: 10.1136/jmg.40.7.e90] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- I Perrault
- Unité de Recherches sur les Handicaps Génétiques de l'Enfant, Hôpital Necker-Enfants Malades, 149 rue de Sévres, 75743 Paris Cedex 15, France
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Rozet JM, Perrault I, Gigarel N, Souied E, Ghazi I, Gerber S, Dufier JL, Munnich A, Kaplan J. Dominant X linked retinitis pigmentosa is frequently accounted for by truncating mutations in exon ORF15 of the RPGR gene. J Med Genet 2002; 39:284-5. [PMID: 11950860 PMCID: PMC1735080 DOI: 10.1136/jmg.39.4.284] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Gerber S, Perrault I, Hanein S, Barbet F, Ducroq D, Ghazi I, Martin-Coignard D, Leowski C, Homfray T, Dufier JL, Munnich A, Kaplan J, Rozet JM. Complete exon-intron structure of the RPGR-interacting protein (RPGRIP1) gene allows the identification of mutations underlying Leber congenital amaurosis. Eur J Hum Genet 2001; 9:561-71. [PMID: 11528500 DOI: 10.1038/sj.ejhg.5200689] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2001] [Revised: 05/17/2001] [Accepted: 05/22/2001] [Indexed: 11/09/2022] Open
Abstract
Leber congenital amaurosis (LCA) is a genetically heterogeneous autosomal recessive condition responsible for congenital blindness or greatly impaired vision since birth. So far, six LCA loci have been mapped but only 4 out of 6 genes have been identified. A genome-wide screen for homozygosity was conducted in seven consanguineous families unlinked to any of the six LCA loci. Evidence for homozygosity was found in two of these seven families at the 14q11 chromosomal region. Two retinal specific candidate genes were known to map to this region, namely the neural retina leucine zipper (NRL) and the retinitis pigmentosa GTPase regulator interacting protein (RPGRIP1). No mutation of the NRL gene was found in any of the two families. Thus, we determined the complete exon-intron structure of the RPGRIP1 gene. RPGRIP1 encompasses 24 coding exons, nine of which are first described here with their corresponding exon-intron boundaries. The screening of the gene in the two families consistent with linkage to chromosome 14q11 allowed the identification of a homozygous null mutation and a homozygous missense mutation, respectively. Further screening of LCA patients unlinked to any of the four already identified LCA genes (n=86) identified seven additional mutations in six of them. In total, eight distinct mutations (5 out of 8 truncating) in 8/93 patients were found. So far this gene accounts for eight out of 142 LCA cases in our series (5.6%).
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Affiliation(s)
- S Gerber
- Unité de Recherches sur les Handicaps Génétiques de l'Enfant, Hôpital Necker-Enfants Malades, Paris, France
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Rozet JM, Perrault I, Gerber S, Hanein S, Barbet F, Ducroq D, Souied E, Munnich A, Kaplan J. Complete abolition of the retinal-specific guanylyl cyclase (retGC-1) catalytic ability consistently leads to leber congenital amaurosis (LCA). Invest Ophthalmol Vis Sci 2001; 42:1190-2. [PMID: 11328726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
Abstract
PURPOSE Leber congenital amaurosis (LCA) is the earliest and the most severe form of all inherited retinal dystrophies. In 1996, the current investigators ascribed the disease in families linked to the LCA1 locus on chromosome 17p13.1 to mutations in the photoreceptor-specific guanylyl cyclase (retGC-1) gene. So far, 22 different mutations, of which 11 are missense mutations, have been identified in 25 unrelated families. This is a report of the functional analyses of nine of the missense mutations. METHODS cDNA constructs were generated that contained the retGC-1 missense mutations identified in patients related to the LCA1 locus. Mutants were expressed in COS7 cells and assayed for their ability to hydrolyze guanosine triphosphate (GTP) into cyclic guanosine monophosphate (cGMP). RESULTS All mutations lying in the catalytic domain showed a complete abolition of cyclase activity. In contrast, only one mutation lying in the extracellular domain also resulted in a severely reduced catalytic activity, whereas the others showed completely normal activity. CONCLUSIONS More than half the mutations identified in patients related to the LCA1 locus are truncating mutations expected to result in a total abolition of retGC-1 activity. Concerning missense mutations, half of them lying in the catalytic domain of the protein also result in the complete inability of the mutant cyclases to hydrolyze GTP into cGMP in vitro. In contrast, missense mutations lying in the extracellular domain, except one affecting the initiation codon, showed normal catalytic activity of retGC-1. Nevertheless, considering that all patients related to the LCA1 locus displayed the same phenotype, it can be assumed that all missense mutations would have the same dramatic consequences on protein activity in vivo as truncation mutations.
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Affiliation(s)
- J M Rozet
- Unité de Recherche sur les Handicaps Génétiques de l'Enfant, Insitut National de la Santé et de la Recherche Médicale U393, Hôpital des Enfants Malades, 149 rue de Sèvres, 75743 Paris Cedex 15, France
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Rozet JM, Gerber S, Perrault I, Calvas P, Souied E, Châtelin S, Molina-Gomez D, Munnich A, Kaplan J. Structure and refinement of the physical mapping of the gamma- glutamylcysteine ligase regulatory subunit (GLCLR) gene to chromosome 1p22.1 within the critically deleted region of human malignant mesothelioma. Cytogenet Cell Genet 2000; 82:91-4. [PMID: 9841137 DOI: 10.1159/000015072] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Glutathione is a ubiquitous antioxidant in mammalian tissues. The first step of its synthesis is catalyzed by the glutamate-cysteine ligase (GLCL) which consists of a heavy, catalytic subunit and a light, regulatory subunit (GLCLR). Previous genetic analyses have revealed frequent losses of chromosome 1p22-->p21 in human malignant mesothelioma and the shortest region of overlapping deletions has been narrowed between the two loci D1S435 and D1S236. An expressed sequence tag of the GLCLR gene was found within a YAC contig encompassing the same interval aoffwas therefore considered as a good candidate gene for predisposition to human mesothelioma. We report here the characterization of the genomic structure of the GLCLR gene and the refine its physical mapping to chromosome 1p22.1.
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Affiliation(s)
- J M Rozet
- Unité de Recherches sur les Handicaps Génétiques de l'Enfant, INSERM U-393, Paris Cedex 15, France
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Gerber S, Rozet JM, Takezawa SI, dos Santos LC, Lopes L, Gribouval O, Penet C, Perrault I, Ducroq D, Souied E, Jeanpierre M, Romana S, Frézal J, Ferraz F, Yu-Umesono R, Munnich A, Kaplan J. The photoreceptor cell-specific nuclear receptor gene (PNR) accounts for retinitis pigmentosa in the Crypto-Jews from Portugal (Marranos), survivors from the Spanish Inquisition. Hum Genet 2000; 107:276-84. [PMID: 11071390 DOI: 10.1007/s004390000350] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.1] [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: 11/24/2022]
Abstract
The last Crypto-Jews (Marranos) are the survivors of Spanish Jews who were persecuted in the late fifteenth century, escaped to Portugal and were forced to convert to save their lives. Isolated groups still exist in mountainous areas such as Belmonte in the Beira-Baixa province of Portugal. We report here the genetic study of a highly consanguineous endogamic population of Crypto-Jews of Belmonte affected with autosomal recessive retinitis pigmentosa (RP). A genome-wide search for homozygosity allowed us to localize the disease gene to chromosome 15q22-q24 (Zmax=2.95 at theta=0 at the D15S131 locus). Interestingly, the photoreceptor cell-specific nuclear receptor (PNR) gene, the expression of which is restricted to the outer nuclear layer of retinal photoreceptor cells, was found to map to the YAC contig encompassing the disease locus. A search for mutations allowed us to ascribe the RP of Crypto-Jews of Belmonte to a homozygous missense mutation in the PNR gene. Preliminary haplotype studies support the view that this mutation is relatively ancient but probably occurred after the population settled in Belmonte.
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Affiliation(s)
- S Gerber
- INSERM U393, Hôpital Necker, Paris, France
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Perrault I, Rozet JM, Gerber S, Ghazi I, Ducroq D, Souied E, Leowski C, Bonnemaison M, Dufier JL, Munnich A, Kaplan J. Spectrum of retGC1 mutations in Leber's congenital amaurosis. Eur J Hum Genet 2000; 8:578-82. [PMID: 10951519 DOI: 10.1038/sj.ejhg.5200503] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.4] [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: 11/09/2022] Open
Abstract
Leber's congenital amaurosis (LCA) is the earliest and most severe form of all inherited retinal dystrophies responsible for congenital blindness. Genetic heterogeneity of LCA has been suspected since the report by Waardenburg of normal children born to affected parents. In 1995 we localised the first disease causing gene, LCA1, to chromosome 17p13 and confirmed the genetic heterogeneity. In 1996 we ascribed LCA1 to mutations in the photoreceptor-specific guanylate cyclase gene (retGC1). Here, we report on the screening of the whole coding sequence of the retGC1 gene in 118 patients affected with LCA. We found 22 different mutations in 24 unrelated families originating from various countries of the world. It is worth noting that all retGC1 mutations consistently caused congenital cone-rod dystrophy in our series, confirming the previous genotype-phenotype correlations we were able to establish. RetGC1 is an essential protein implicated in the phototransduction cascade, especially in the recovery of the dark state after the excitation process of photoreceptor cells by light stimulation. We postulate that the retGC1 mutations hinder the restoration of the basal level of cGMP of cone and rod photoreceptor cells, leading to a situation equivalent to consistent light exposure during photoreceptor development, explaining the severity of the visual disorder at birth.
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Affiliation(s)
- I Perrault
- Service de Génétique Médicale et Unité de Recherches sur les Handicaps Génétiques de l'Enfant, INSERM U393, Hôpital des Enfants Malades, Paris, France
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Sohocki MM, Perrault I, Leroy BP, Payne AM, Dharmaraj S, Bhattacharya SS, Kaplan J, Maumenee IH, Koenekoop R, Meire FM, Birch DG, Heckenlively JR, Daiger SP. Prevalence of AIPL1 mutations in inherited retinal degenerative disease. Mol Genet Metab 2000; 70:142-50. [PMID: 10873396 DOI: 10.1006/mgme.2000.3001] [Citation(s) in RCA: 118] [Impact Index Per Article: 4.9] [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] [Indexed: 11/22/2022]
Abstract
Leber congenital amaurosis (LCA) is the most severe form of inherited retinal dystrophy and the most frequent cause of inherited blindness in children. LCA is usually inherited in an autosomal recessive fashion, although rare dominant cases have been reported. One form of LCA, LCA4, maps to chromosome 17p13 and is genetically distinct from other forms of LCA. We recently identified the gene associated with LCA4, AIPL1 (aryl-hydrocarbon interacting protein-like 1) and identified three mutations that were the cause of blindness in five families with LCA. In this study, AIPL1 was screened for mutations in 512 unrelated probands with a range of retinal degenerative diseases to determine if AIPL1 mutations cause other forms of inherited retinal degeneration and to determine the relative contribution of AIPL1 mutations to inherited retinal disorders in populations worldwide. We identified 11 LCA families whose retinal disorder is caused by homozygous or compound heterozygous AIPL1 mutations. We also identified affected individuals in two apparently dominant families, diagnosed with juvenile retinitis pigmentosa or dominant cone-rod dystrophy, respectively, who are heterozygous for a 12-bp AIPL1 deletion. Our results suggest that AIPL1 mutations cause approximately 7% of LCA worldwide and may cause dominant retinopathy.
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Affiliation(s)
- M M Sohocki
- Human Genetics Center, School of Public Health, Houston, Texas, 77225-0334, USA
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Souied EH, Ducroq D, Rozet JM, Gerber S, Perrault I, Munnich A, Coscas G, Soubrane G, Kaplan J. ABCR gene analysis in familial exudative age-related macular degeneration. Invest Ophthalmol Vis Sci 2000; 41:244-7. [PMID: 10634626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
PURPOSE Identification of genetic factors in the pathogenesis of age-related macular degeneration (AMD) is of crucial importance in this common cause of blindness. Mutations in the Stargardt disease gene (ABCR) were previously reported in patients with atrophic forms of AMD. The purpose of this study was to analyze familial segregation of ABCR gene mutations in 52 unrelated multiplex cases of exudative AMD. METHODS A complete ophthalmological examination including visual acuity measurement, fundus examination, and fluorescein angiography (FA) was performed on each exudative AMD patient. The entire coding sequence of the ABCR gene was analyzed using a combination of single-strand conformation polymorphism and confirmatory sequencing of the exons showing an abnormal pattern of migration. RESULTS Six heterozygous missense changes were identified. A lack of familial segregation was observed in 4 of 6 codon changes (Arg943Gln, Val1433Ile, Pro1948Leu, and Ser2255Ile). Conversely, 2 codon changes cosegregated with the disease in 2 small families: Pro940Arg and Leu1970Phe. CONCLUSIONS The authors believe that segregation of the ABCR gene mutations with familial cases of AMD has not yet been shown. The analysis of familial segregation allowed the authors to exclude 4 of 6 codon changes as disease-causing mutations. Furthermore, it was shown here that the ABCR gene may be rarely involved in exudative AMD, with at best 2 of 52 familial cases (4%) related to this susceptibility factor.
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Affiliation(s)
- E H Souied
- INSERM U-393, Hôpital des Enfants-Malades, Paris, France
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Rozet JM, Gerber S, Souied E, Ducroq D, Perrault I, Ghazi I, Soubrane G, Coscas G, Dufier JL, Munnich A, Kaplan J. The ABCR gene: a major disease gene in macular and peripheral retinal degenerations with onset from early childhood to the elderly. Mol Genet Metab 1999; 68:310-5. [PMID: 10527682 DOI: 10.1006/mgme.1999.2925] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- J M Rozet
- Unité de Recherches sur les Handicaps Génétiques de l'Enfant, INSERM U393, Hôpital des Enfants Malades, 149 rue de Sèvres, Paris Cedex 15, 75743, France
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Abstract
Leber's congenital amaurosis (LCA) is the earliest and most severe form of all inherited retinal dystrophies responsible for congenital blindness. Genetic heterogeneity of LCA has been suspected since the report by Waardenburg of normal children born to affected parents. In 1995, we localized the first disease causing gene, LCA1, to chromosome 17p13 and confirmed the genetic heterogeneity. In 1996, we ascribed LCA1 to mutations in the photoreceptor-specific guanylate cyclase gene (retGC1). RetGC1 is an essential protein implicated in the phototransduction cascade, especially in the recovery of the dark state after the excitation process of photoreceptor cells by light stimulation. In 1997, mutations in a second gene were reported in LCA, the RPE65 gene, which is the first specific retinal pigment epithelium gene. The protein RPE65 is implicated in the metabolism of vitamin A, the precursor of the photoexcitable retinal pigment (rhodopsin). Finally, a third gene, CRX, implicated in photoreceptor development, has been suspected of causing a few cases of LCA. Taken together, these three genes account for only 27% of LCA cases in our series. The three genes encode proteins that are involved in completely different physiopathologic pathways. Based on these striking differences of physiopathologic processes, we reexamined all clinical physiopathological discrepancies and the results strongly suggested that retGC1 gene mutations are responsible for congenital stationary severe cone-rod dystrophy, while RPE65 gene mutations are responsible for congenital severe but progressive rod-cone dystrophy. It is of tremendous importance to confirm and to refine these genotype-phenotype correlations on a large scale in order to anticipate the final outcome in a blind infant, on the one hand, and to further guide genetic studies in older patients on the other hand.
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Affiliation(s)
- I Perrault
- Service de Génétique Médicale et Unité de Recherches sur les Handicaps Génétiques de l'Enfant, INSERM U-393, Hôpital des Enfants-Malades, 149 rue de Sèvres, Paris Cedex 15, 75743, France
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22
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Souied EH, Ducroq D, Rozet JM, Gerber S, Perrault I, Sterkers M, Benhamou N, Munnich A, Coscas G, Soubrane G, Kaplan J. A novel ABCR nonsense mutation responsible for late-onset fundus flavimaculatus. Invest Ophthalmol Vis Sci 1999; 40:2740-4. [PMID: 10509673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023] Open
Abstract
PURPOSE To report the ophthalmologic features of a novel truncating mutation in the ABCR gene in a patient affected with late-onset fundus flavimaculatus (FFM). METHODS A complete ophthalmologic examination was performed in a 70-year-old patient, including best-corrected visual acuity measurement, slit lamp and fundus examination, fundus photographs, frequent fluorescein and indocyanine green angiographies, visual field testing, color vision analysis, electroretinogram, and electro-oculogram. The 50 exons of the ABCR gene were analyzed using direct sequencing. RESULTS Fluorescein and indocyanine green angiographies confirmed the diagnosis of FFM. A heterozygous base change was found, resulting in the substitution of an arginine to a stop at codon 152 of the ABCR gene. CONCLUSIONS A heterozygous nonsense ABCR gene mutation was found in a patient affected with FFM. No other mutation has been identified in the entire coding sequence and the promoter region, suggesting that a heterozygous severe ABCR mutant may be responsible for a mild and delayed FFM phenotype, different from that of age-related macular degeneration.
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Affiliation(s)
- E H Souied
- Institut National de la Santé et de la Recherche Médicale U-393, Hôpital des Enfants-Malades, Paris, France
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23
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Souied EH, Ducroq D, Gerber S, Ghazi I, Rozet JM, Perrault I, Munnich A, Dufier JL, Coscas G, Soubrane G, Kaplan J. Age-related macular degeneration in grandparents of patients with Stargardt disease: genetic study. Am J Ophthalmol 1999; 128:173-8. [PMID: 10458172 DOI: 10.1016/s0002-9394(99)00145-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [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: 11/26/2022]
Abstract
PURPOSE To report clinical features and molecular genetic study in three unrelated families in which age-related macular degeneration was observed in grandparents of patients with Stargardt disease. METHODS A complete ophthalmologic examination including best-corrected visual acuity measurement, fundus examination, and fluorescein angiography was performed on all members of the three families. The entire coding sequence of the ABCR gene was analyzed using a combination of single strand conformation polymorphism and direct sequence analysis of the 50 exons. RESULTS Compound heterozygous missense mutations were observed in patients with Stargardt disease (Arg212Cys, Argl107Cys, Gly1977Ser, Arg2107His, and le2113Met). Heterozygous missense mutations were observed in the grandparents with age-related macular degeneration (Arg212Cys and Arg1107Cys). CONCLUSIONS We report phenotype and genotype findings in three unrelated families segregating patients with Stargardt disease and age-related macular degeneration. The hypothesis that the Arg212Cys and Arg1107Cys ABCR gene mutations could be susceptibility factors for age-related macular degeneration is discussed. We speculate that the relatives of patients affected with Stargardt disease who are carriers of heterozygous ABCR gene mutations may have a higher risk of developing age-related macular degeneration.
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Affiliation(s)
- E H Souied
- Clinique Ophtamologique Universitaire de Créteil, France
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24
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Rozet JM, Gerber S, Ghazi I, Perrault I, Ducroq D, Souied E, Cabot A, Dufier JL, Munnich A, Kaplan J. Mutations of the retinal specific ATP binding transporter gene (ABCR) in a single family segregating both autosomal recessive retinitis pigmentosa RP19 and Stargardt disease: evidence of clinical heterogeneity at this locus. J Med Genet 1999; 36:447-51. [PMID: 10874631 PMCID: PMC1734380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Stargardt disease (STGD) is an autosomal recessive macular dystrophy of childhood characterised by bilateral loss of central vision over a period of several months. STGD has been mapped to chromosome 1p22.1 and recently ascribed to mutations in the retinal specific ATP binding transporter gene (ABCR). The fundus flavimaculatus with macular dystrophy (FFM), an autosomal recessive condition responsible for gradual loss of visual acuity in adulthood (second to third decade) has also been mapped to the same locus. However, a gene for autosomal recessive retinitis pigmentosa with distinctive features of choriocapillaris atrophy at an advanced stage (RP19) has been mapped to the genetic interval encompassing the STGD gene on chromosome 1p (D1S435-D1S236), raising the question of whether, despite striking differences in clinical course and presentation, RP19 and STGD might be allelic disorders at the ABCR locus. In a family segregating RP and STGD in two first cousins, we found that heterozygosity for a splicing mutation in the ABCR gene (1938-1 G-->A) resulted in STGD while hemizygosity for this splice mutation resulted in RP, and when studying the RP patient's parents, we found a maternal non-contribution with apparent segregation of a null allele ascribed to a partial deletion of the ABCR gene. The present study shows that, despite striking clinical differences, RP19 and STGD are allelic disorders at the ABCR locus.
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Affiliation(s)
- J M Rozet
- Unité de Recherches sur les Handicaps Génétiques de l'Enfant INSERM U-393, Paris, France
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25
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Cabot A, Rozet JM, Gerber S, Perrault I, Ducroq D, Smahi A, Souied E, Munnich A, Kaplan J. A gene for X-linked idiopathic congenital nystagmus (NYS1) maps to chromosome Xp11.4-p11.3. Am J Hum Genet 1999; 64:1141-6. [PMID: 10090899 PMCID: PMC1377838 DOI: 10.1086/302324] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.4] [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: 11/03/2022] Open
Abstract
Congenital nystagmus (CN) is a common oculomotor disorder (frequency of 1/1,500 live births) characterized by bilateral uncontrollable ocular oscillations, with onset typically at birth or within the first few months of life. This condition is regarded as idiopathic, after exclusion of nervous and ocular diseases. X-linked, autosomal dominant, and autosomal recessive modes of inheritance have been reported, but X-linked inheritance is probably the most common. In this article, we report the mapping of a gene for X-linked dominant CN (NYS1) to the short arm of chromosome X, by showing close linkage of NYS1 to polymorphic markers on chromosome Xp11.4-p11.3 (maximum LOD score of 3.20, over locus DXS993). Because no candidate gene, by virtue of its function, has been found in this region of chromosome Xp, further studies are required, to reduce the genetic interval encompassing the NYS1 gene. It is hoped that the complete gene characterization will address the complex pathophysiology of CN.
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Affiliation(s)
- A Cabot
- Unité de Recherches sur les Handicaps Génétiques de l'Enfant, Institut National de la Santé et de la Recherche Médicale U393, Hôpital des Enfants Malades, Paris, France
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26
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Perrault I, Rozet JM, Ghazi I, Leowski C, Bonnemaison M, Gerber S, Ducroq D, Cabot A, Souied E, Dufier JL, Munnich A, Kaplan J. Different functional outcome of RetGC1 and RPE65 gene mutations in Leber congenital amaurosis. Am J Hum Genet 1999; 64:1225-8. [PMID: 10090910 PMCID: PMC1377849 DOI: 10.1086/302335] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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27
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Perrault I, Rozet JM, Gerber S, Kelsell RE, Souied E, Cabot A, Hunt DM, Munnich A, Kaplan J. A retGC-1 mutation in autosomal dominant cone-rod dystrophy. Am J Hum Genet 1998; 63:651-4. [PMID: 9683616 PMCID: PMC1377325 DOI: 10.1086/301985] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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Kelsell RE, Gregory-Evans K, Payne AM, Perrault I, Kaplan J, Yang RB, Garbers DL, Bird AC, Moore AT, Hunt DM. Mutations in the retinal guanylate cyclase (RETGC-1) gene in dominant cone-rod dystrophy. Hum Mol Genet 1998; 7:1179-84. [PMID: 9618177 DOI: 10.1093/hmg/7.7.1179] [Citation(s) in RCA: 160] [Impact Index Per Article: 6.2] [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: 11/14/2022] Open
Abstract
The dominant cone-rod dystrophy gene CORD6 has previously been mapped to within an 8 cM interval on chromosome 17p12-p13. The retinal-specific guanylate cyclase gene (RETGC-1), which maps to within this genetic interval and previously was implicated in Leber's congenital amaurosis, was screened for mutations within this family and in a panel of small families and individuals with various cone and cone- rod dystrophy phenotypes. A missense mutation (E837D) was identified in affected members of the CORD6 family, as well as a second missense mutation (R838C) in three other families with dominant cone-rod dystrophy. RETGC-1 is only the fourth gene to be implicated in cone-rod dystrophy and this is the first report of dominant mutations in this gene.
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Affiliation(s)
- R E Kelsell
- Department of Molecular Genetics, Institute of Ophthalmology, University College London, Bath Street, London EC1V 9EL, UK
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29
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Rozet JM, Gerber S, Souied E, Perrault I, Châtelin S, Ghazi I, Leowski C, Dufier JL, Munnich A, Kaplan J. Spectrum of ABCR gene mutations in autosomal recessive macular dystrophies. Eur J Hum Genet 1998; 6:291-5. [PMID: 9781034 DOI: 10.1038/sj.ejhg.5200221] [Citation(s) in RCA: 110] [Impact Index Per Article: 4.2] [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: 11/08/2022] Open
Abstract
Stargardt disease (STGD) and late-onset fundus flavimaculatus (FFM) are autosomal recessive conditions leading to macular degenerations in childhood and adulthood, respectively. Recently, mutations of the photoreceptor cell-specific ATP binding transporter gene (ABCR) have been reported in Stargardt disease. Here, we report on the screening of the whole coding sequence of the ABCR gene in 40 unrelated STGD and 15 FFM families and we show that mutations truncating the ABCR protein consistently led to STGD. Conversely, all mutations identified in FFM were missense mutations affecting uncharged amino acids. These results provide the first genotype-phenotype correlations in ABCR gene mutations.
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Affiliation(s)
- J M Rozet
- Unité de Recherches sur les Handicaps Génétiques de l'Enfant INSERM U-393, Hôpital Necker-Enfants Malades, Paris, France.
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30
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Perrault I, Châtelin S, Nancy V, Rozet JM, Gerber S, Ghazi I, Souied E, Dufier JL, Munnich A, de Gunzburg J, Kaplan J. Exclusion of five subunits of cGMP phosphodiesterase in Leber's congenital amaurosis. Hum Genet 1998; 102:322-6. [PMID: 9544846 DOI: 10.1007/s004390050699] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [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: 02/07/2023]
Abstract
Leber's congenital amaurosis (LCA) is the earliest and most severe of all inherited retinal dystrophies. Recently, we mapped an LCA gene to chromosome 17p13.1 (LCA1) and ascribed the disease to mutations of the retinal guanylate cyclase (ret GC) gene in a subset of families of North African ancestry. Owing to the genetic heterogeneity of LCA and considering that LCA1 results from an impaired production of cGMP in the retina (with permanent closure of cGMP-gated cation channels), we hypothesized that the activation of the cGMP phosphodiesterase (PDE) could trigger the disease by lowering the intracellular cGMP level in the retina. The rod and cone cGMP-PDE inhibitory subunits were regarded therefore as candidate genes in LCA. Here, we report the exclusion of five rod and cone cGMP-PDE subunits in LCA families unlinked to chromosome 17p13.
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Affiliation(s)
- I Perrault
- Unité de Recherches sur les Handicaps Génétiques de l'Enfant, INSERM U-393, Département de Génétique, Hôpital des Enfants-Malades, Paris, France
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31
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Kaplan J, Rozet JM, Gerber S, Souied É, Perrault I, Ducroq D, Munnich A. Génétique des dégénérescences maculaires. Med Sci (Paris) 1998. [DOI: 10.4267/10608/971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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32
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Souied E, Segues B, Ghazi I, Rozet JM, Chatelin S, Gerber S, Perrault I, Michel-Awad A, Briard ML, Plessis G, Dufier JL, Munnich A, Kaplan J. Severe manifestations in carrier females in X linked retinitis pigmentosa. J Med Genet 1997; 34:793-7. [PMID: 9350809 PMCID: PMC1051083 DOI: 10.1136/jmg.34.10.793] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [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: 02/05/2023]
Abstract
Retinitis pigmentosa (RP) is a group of progressive hereditary disorders of the retina in which various modes of inheritance have been described. Here, we report on X linked RP in nine families with constant and severe expression in carrier females. In our series, however, the phenotype was milder and delayed in carrier females compared to hemizygous males. This form of X linked RP could be regarded therefore as partially dominant. The disease gene maps to chromosome Xp2.1 in the genetic interval encompassing the RP3 locus (Zmax=13.71 at the DXS1100 locus). Single strand conformation polymorphism and direct sequence analysis of the retinitis pigmentosa GTPase regulator (RPGR) gene, which accounts for RP3, failed to detect any mutation in our families. Future advances in the identification of X linked RP genes will hopefully help to elucidate the molecular basis of this X linked dominant RP.
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Affiliation(s)
- E Souied
- Unité de Recherches sur les Handicaps Génétiques de 1'Enfant, INSERM U-393, Hôpital des Enfants-Malades, Paris, France
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33
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Perrault I, Rozet JM, Calvas P, Gerber S, Camuzat A, Dollfus H, Châtelin S, Souied E, Ghazi I, Leowski C, Bonnemaison M, Le Paslier D, Frézal J, Dufier JL, Pittler S, Munnich A, Kaplan J. Retinal-specific guanylate cyclase gene mutations in Leber's congenital amaurosis. Nat Genet 1996; 14:461-4. [PMID: 8944027 DOI: 10.1038/ng1296-461] [Citation(s) in RCA: 314] [Impact Index Per Article: 11.2] [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: 02/03/2023]
Abstract
Leber's congenital amaurosis (LCA, MIM 204,000), the earliest and most severe form of inherited retinopathy, accounts for at least 5% of all inherited retinal dystrophies. This autosomal recessive condition is usually recognized at birth or during the first months of life in an infant with total blindness or greatly impaired vision, normal fundus and extinguished electroretinogram (ERG). Nystagmus (pendular type) and characteristic eye poking are frequently observed in the first months of life (digito-ocular sign of Franceschetti). Hypermetropia and keratoconus frequently develop in the course of the disease. The observation by Waardenburg of normal children born to affected parents supports the genetic heterogeneity of LCA. Until now, however, little was known about the pathophysiology of the disease, but LCA is usually regarded as the consequence of either impaired development of photoreceptors or extremely early degeneration of cells that have developed normally. We have recently mapped a gene for LCA to chromosome 17p13.1 (LCA1) by homozygosity mapping in consanguineous families of North African origin and provided evidence of genetic heterogeneity in our sample, as LCA1 accounted for 8/15 LCA families in our series. Here, we report two missense mutations (F589S) and two frameshift mutations (nt 460 del C, nt 693 del C) of the retinal guanylate cyclase (RETGC, GDB symbol GUC2D) gene in four unrelated LCA1 probands of North African ancestry and ascribe LCA1 to an impaired production of cGMP in the retina, with permanent closure of cGMP-gated cation channels.
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Affiliation(s)
- I Perrault
- Unité de Recherches sur les Handicaps Génétiques de l'Enfant, INSERM U-393, Hôpital des Enfants-malades, Paris, France
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34
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Rozet JM, Gerber S, Perrault I, Camuzat A, Calvas P, Viegas-Pequignot E, Molina-Gomes D, Le Paslier D, Chumakov I, Munnich A, Kaplan J. Structure and physical mapping of DR1, a TATA-binding protein-associated phosphoprotein gene, to chromosome 1p22.1 and its exclusion in Stargardt disease (STGD). Genomics 1996; 36:554-6. [PMID: 8884286 DOI: 10.1006/geno.1996.0508] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- J M Rozet
- Unité de Recherches sur les Handicaps Génétiques de l'Enfant, INSERM U-393, Hôpital des Enfants Malades, Paris, France
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35
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Camuzat A, Rozet JM, Dollfus H, Gerber S, Perrault I, Weissenbach J, Munnich A, Kaplan J. Evidence of genetic heterogeneity of Leber's congenital amaurosis (LCA) and mapping of LCA1 to chromosome 17p13. Hum Genet 1996; 97:798-801. [PMID: 8641699 DOI: 10.1007/bf02346192] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.2] [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: 02/01/2023]
Abstract
Leber's congenital amaurosis (LCA) is an autosomal recessive disease responsible for congenital blindness. It is the earliest and most severe inherited retinal dystrophy in human and its genetic heterogeneity has long been recognised. We have recently reported on the first localisation of a disease gene (LCA1) to the short arm of chromosome 17 by homozygosity mapping in five families of North African origin. Here, we refine the genetic mapping of LCA1 to chromosome 17p13 between loci D17S938 and D17S1353 and provide strong support for the genetic heterogeneity of this condition (maximum likelihood for heterogeneity, 17.20 in InL; heterogeneity versus homogeneity, P = 0.0002, heterogeneity versus no linkage, P < 0.0001)
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Affiliation(s)
- A Camuzat
- Service de Génétique et Unité de Recherches sur les Handicaps, INSERM U. 393, Hôpital des Enfants Malades, Paris, France
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Simard-Savoie S, Perrault I, Perron MJ. Effects of articaine on intrapulpal, mandibular, and femoral pressures in dogs. Anesth Prog 1990; 37:16-9. [PMID: 2077980 PMCID: PMC2163536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Articaine, a new local anesthetic and the first substance of the amide type with a thiophene ring, has been studied to evaluate its effects on intrapulpal blood pressure (IPP) and mandibular and femoral pressures (MAP, FAP) after injections in the posterior mental foramen (PMF). Eight mongrel dogs of either sex, 9-12 months of age weighing from 15-25 kg were anesthetized. The PMF and the middle foramen were uncovered to expose the vascular-nerve bundle. The mandibular artery was dissected, cannulated, and filled with a heparinized normal saline solution. A 27-gauge needle was placed into the PMF for the injections of the local anesthetic. Into the ipsilateral canine, a cannula hermetically sealed and filled with heparinized saline solution was inserted. All hemodynamic measurements (IPP, MAP, FAP) were recorded with a precalibrated polygraph. The results obtained allow us to conclude that articaine 4% with epinephrine 1:100,000 injected in the PMF (0.3 ml), produces a drop of the intrapulpal blood pressure due to a strong vasoconstriction, whereas this effect is less pronounced at the MAP level and almost inexistent in the FAP.
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