RESUMEN
Proliferative vasculopathy and hydranencephaly-hydrocephaly syndrome (PVHH), also known as Fowler syndrome, is an autosomal-recessively inherited prenatal lethal disorder characterized by hydranencephaly; brain stem, basal ganglia, and spinal cord diffuse clastic ischemic lesions with calcifications; glomeruloid vasculopathy of the central nervous system and retinal vessels; and a fetal akinesia deformation sequence (FADS) with muscular neurogenic atrophy. To identify the molecular basis for Fowler syndrome, we performed autozygosity mapping studies in three consanguineous families. The results of SNP microarrays and microsatellite marker genotyping demonstrated linkage to chromosome 14q24.3. Direct sequencing of candidate genes within the target interval revealed five different germline mutations in FLVCR2 in five families with Fowler syndrome. FLVCR2 encodes a transmembrane transporter of the major facilitator superfamily (MFS) hypothesized to be involved in regulation of growth, calcium exchange, and homeostasis. This is the first gene to be associated with Fowler syndrome, and this finding provides a basis for further studies to elucidate the pathogenetic mechanisms and phenotypic spectrum of associated disorders.
Asunto(s)
Mutación de Línea Germinal , Hidranencefalia/genética , Hidrocefalia/genética , Proteínas de Transporte de Membrana/genética , Receptores Virales/genética , Enfermedades Vasculares/genética , Anomalías Múltiples/genética , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Animales , Secuencia de Bases , Cromosomas Humanos Par 14/genética , Consanguinidad , Secuencia Conservada , ADN/genética , Femenino , Genes Recesivos , Humanos , Masculino , Ratones , Modelos Moleculares , Datos de Secuencia Molecular , Análisis de Secuencia por Matrices de Oligonucleótidos , Linaje , Fenotipo , Polimorfismo de Nucleótido Simple , Embarazo , Estructura Terciaria de Proteína , Homología de Secuencia de Aminoácido , SíndromeRESUMEN
The histiocytoses are a heterogeneous group of disorders characterised by an excessive number of histiocytes. In most cases the pathophysiology is unclear and treatment is nonspecific. Faisalabad histiocytosis (FHC) (MIM 602782) has been classed as an autosomal recessively inherited form of histiocytosis with similarities to Rosai-Dorfman disease (RDD) (also known as sinus histiocytosis with massive lymphadenopathy (SHML)). To elucidate the molecular basis of FHC, we performed autozygosity mapping studies in a large consanguineous family and identified a novel locus at chromosome 10q22.1. Mutation analysis of candidate genes within the target interval identified biallelic germline mutations in SLC29A3 in the FHC kindred and in two families reported to have familial RDD. Analysis of SLC29A3 expression during mouse embryogenesis revealed widespread expression by e14.5 with prominent expression in the central nervous system, eye, inner ear, and epithelial tissues including the gastrointestinal tract. SLC29A3 encodes an intracellular equilibrative nucleoside transporter (hENT3) with affinity for adenosine. Recently germline mutations in SLC29A3 were also described in two rare autosomal recessive disorders with overlapping phenotypes: (a) H syndrome (MIM 612391) that is characterised by cutaneous hyperpigmentation and hypertrichosis, hepatomegaly, heart anomalies, hearing loss, and hypogonadism; and (b) PHID (pigmented hypertrichosis with insulin-dependent diabetes mellitus) syndrome. Our findings suggest that a variety of clinical diagnoses (H and PHID syndromes, FHC, and familial RDD) can be included in a new diagnostic category of SLC29A3 spectrum disorder.
Asunto(s)
Histiocitosis Sinusal/genética , Mutación/genética , Proteínas de Transporte de Nucleósidos/genética , Alelos , Animales , Secuencia de Bases , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Línea Celular Tumoral , Proliferación Celular , Cromosomas Humanos Par 10/genética , Ensayo de Unidades Formadoras de Colonias , Análisis Mutacional de ADN , Embrión de Mamíferos/metabolismo , Familia , Femenino , Regulación de la Expresión Génica , Sitios Genéticos/genética , Histiocitosis Sinusal/patología , Humanos , Ratones , Datos de Secuencia Molecular , Proteínas de Transporte de Nucleósidos/metabolismo , Mapeo Físico de Cromosoma , ARN Interferente Pequeño/metabolismo , Síndrome , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/patologíaRESUMEN
Goose bone is traditionally applied for many ailments including bone fractures. Goose bone that consists of calcium phosphate plays a major role in bone regeneration. In this study, the production of goose bone ash (GBA) was translated from a traditional process into one of a laboratory scale via thermal and mechanical methods. The GBA was thermally processed via calcination at 300 °C and 900 °C. The differences in physicochemical properties between studied GBA (SGBA) and commercial GBA (CGBA) were elucidated via Fourier transform infrared (FT-IR), X-ray fluorescence (XRF), X-ray diffraction (XRD) and electron diffraction X-Ray (EDX). The morphological properties of SGBA and CGBA were characterized using field emission scanning electron microscopy (FESEM) in which nano-sized particles were detected. The results showed that the SGBA of 300 °C had comparable physicochemical properties to those of CGBA. A high processing temperature was associated with decreasing organic compounds and increasing crystallinity. The finding from EDX suggests that sintering at 900 °C (SGBA 900) demonstrated the presence of hydroxyapatite in the mineralogical phase and had a Ca/P atomic ratio of 1.64 which is comparable to the ideal stoichiometric ratio of 1.67. Findings from this study could be used for the further exploration of GBA as a potential material for bone regeneration via the elucidation of their biological properties in the next experimental setting.
RESUMEN
Beckwith-Wiedemann syndrome (BWS) is a fetal overgrowth and human imprinting disorder resulting from the deregulation of a number of genes, including IGF2 and CDKN1C, in the imprinted gene cluster on chromosome 11p15.5. Most cases are sporadic and result from epimutations at either of the two 11p15.5 imprinting centres (IC1 and IC2). However, rare familial cases may be associated with germline 11p15.5 deletions causing abnormal imprinting in cis. We report a family with BWS and an IC2 epimutation in which affected siblings had inherited different parental 11p15.5 alleles excluding an in cis mechanism. Using a positional-candidate gene approach, we found that the mother was homozygous for a frameshift mutation in exon 6 of NLRP2. While germline mutations in NLRP7 have previously been associated with familial hydatidiform mole, this is the first description of NLRP2 mutation in human disease and the first report of a trans mechanism for disordered imprinting in BWS. These observations are consistent with the hypothesis that NLRP2 has a previously unrecognised role in establishing or maintaining genomic imprinting in humans.
Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Síndrome de Beckwith-Wiedemann/genética , Impresión Genómica , Proteínas Reguladoras de la Apoptosis , Cromosomas Humanos Par 11 , Exones , Salud de la Familia , Femenino , Mutación del Sistema de Lectura , Homocigoto , Humanos , MadresRESUMEN
PURPOSE: To define the phenotype and elucidate the molecular basis for an autosomal recessively inherited optic atrophy and auditory neuropathy in a consanguineous family with two affected children. METHODS: Family members underwent detailed ophthalmologic, electrophysiological, and audiological assessments. An autozygosity mapping strategy using high-density single nucleotide polymorphism microarrays and microsatellite markers was used to detect regions of genome homozygosity that might contain the disease gene. Candidate genes were then screened for mutations by direct sequencing. RESULTS: Both affected subjects had poor vision from birth and complained of progressive visual loss over time. Current visual acuity ranged from 6/60 to 6/120. Fundus examination revealed bilateral temporal optic nerve pallor in both patients with otherwise normal retinal findings. International-standard full-field electroretinograms were normal in both individuals, with no evidence of generalized retinal dysfunction. Pattern cortical visual evoked potentials were grossly abnormal bilaterally in both cases. The pattern electroretinogram N95:P50 ratio was subnormal, and the P50 was of shortened peak time bilaterally in both patients. The electrophysiological findings were consistent with bilateral retinal ganglion cell/optic nerve dysfunction. Audiological investigation in both siblings revealed abnormalities falling within the auditory neuropathy/dysynchrony spectrum. There were no auditory symptoms and good outer hair cell function (as demonstrated by transient evoked otoacoustic emissions) but impaired inner hair cell/neural function with abnormal stapedial reflex thresholds and abnormal or absent auditory brainstem-evoked responses. The single nucleotide polymorphism microarray data demonstrated a 24.17 Mb region of homozygosity at 11q14.1-11q22.3, which was confirmed by microsatellite marker analysis. The candidate target region contained the transmembrane protein 126A (TMEM126A) gene, and direct sequencing identified a previously described nonsense mutation (c.163C>T; p.Arg55X). CONCLUSIONS: We describe the first detailed phenotyping of patients with autosomal recessive TMEM126A-associated optic atrophy and auditory neuropathy. These findings will facilitate the identification of individuals with this recently described disorder.
Asunto(s)
Enfermedades Auditivas Centrales/complicaciones , Enfermedades Auditivas Centrales/genética , Codón sin Sentido/genética , Genes Recesivos/genética , Proteínas de la Membrana/genética , Atrofias Ópticas Hereditarias/complicaciones , Atrofias Ópticas Hereditarias/genética , Adolescente , Audiometría de Tonos Puros , Enfermedades Auditivas Centrales/fisiopatología , Umbral Auditivo/fisiología , Secuencia de Bases , Análisis Mutacional de ADN , Electrorretinografía , Potenciales Evocados Auditivos del Tronco Encefálico/fisiología , Potenciales Evocados Visuales/fisiología , Femenino , Fondo de Ojo , Ligamiento Genético , Humanos , Masculino , Datos de Secuencia Molecular , Fibras Nerviosas/patología , Atrofias Ópticas Hereditarias/fisiopatología , Emisiones Otoacústicas Espontáneas/fisiología , Linaje , Neuronas Retinianas/patología , Adulto JovenRESUMEN
PURPOSE: To identify the molecular basis for autosomal recessively inherited congenital non-syndromic pulverulent cataracts in a consanguineous family with four affected children. METHODS: An autozygosity mapping strategy using high density SNP microarrays and microsatellite markers was employed to detect regions of homozygosity. Subsequently good candidate genes were screened for mutations by direct sequencing. RESULTS: The SNP microarray data demonstrated a 24.96 Mb region of homozygosity at 22q11.21-22q13.2 which was confirmed by microsatellite marker analysis. The candidate target region contained the beta-crystallin gene cluster and direct sequencing in affected family members revealed a novel mutation in CRYBB1 (c.2T>A; p.Met1Lys). CONCLUSIONS: To our knowledge this is the first case of an initiation codon mutation in a human crystallin gene, and only the second report of a CRYBB1 mutation associated with autosomal recessive congenital cataracts. In addition, although a number of genetic causes of autosomal dominant pulverulent cataracts have been identified (including CRYBB1) this is the first gene to have been implicated in autosomal recessive nuclear pulverulent cataract.
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Catarata/genética , Codón Iniciador/genética , Genes Recesivos , Polimorfismo de Nucleótido Simple , Cadena B de beta-Cristalina/genética , Análisis Mutacional de ADN , Familia , Humanos , Repeticiones de Microsatélite , Análisis de Secuencia por Matrices de OligonucleótidosRESUMEN
Distal deletion of chromosome 3p25-pter (3p- syndrome) produces a distinct clinical syndrome characterized by low birth weight, mental retardation, telecanthus, ptosis, and micrognathia. Congenital heart disease (CHD), typically atrioventricular septal defect (AVSD) occurs in about a third of patients. Previously we reported on an association between the presence of CHD and the proximal extent of the deletion such that a CHD susceptibility gene was mapped between D3S1263 and D3S3594. In addition, we and others have suggested several candidate genes for the psychomotor retardation usually seen with constitutional 3p25 deletions. In order to further investigate genotype-phenotype correlations in 3p- syndrome we analyzed 14 patients with cytogenetically detectable deletions of 3p25 (including one patient with a normal phenotype) using Affymetrix 250K SNP microarrays. Deletion size varied from approximately 6 to 12 Mb. Assuming complete penetrance, a candidate critical region for a CHD susceptibility gene was refined to approximately 200 kb and a candidate critical region for mental retardation was mapped to an approximately 1 Mb interval containing SRGAP3 but other 3p neurodevelopmental genes including CHL1, CNTN4, LRRN1, and ITPR1 mapped outside the candidate critical interval. We suggest that current evidence suggests that SRGAP3 is the major determinant of mental retardation in distal 3p deletions.
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Deleción Cromosómica , Cromosomas Humanos Par 3 , Análisis de Secuencia por Matrices de Oligonucleótidos , Niño , Proteínas Activadoras de GTPasa/genética , Proteínas Activadoras de GTPasa/fisiología , Dosificación de Gen , Perfilación de la Expresión Génica , Genotipo , Cardiopatías Congénitas/genética , Humanos , Discapacidad Intelectual/genética , Fenotipo , Polimorfismo de Nucleótido Simple , SíndromeRESUMEN
BACKGROUND: The generation of large amounts of microarray data presents challenges for data collection, annotation, exchange and analysis. Although there are now widely accepted formats, minimum standards for data content and ontologies for microarray data, only a few groups are using them together to build and populate large-scale databases. Structured environments for data management are crucial for making full use of these data. DESCRIPTION: The MiMiR database provides a comprehensive infrastructure for microarray data annotation, storage and exchange and is based on the MAGE format. MiMiR is MIAME-supportive, customised for use with data generated on the Affymetrix platform and includes a tool for data annotation using ontologies. Detailed information on the experiment, methods, reagents and signal intensity data can be captured in a systematic format. Reports screens permit the user to query the database, to view annotation on individual experiments and provide summary statistics. MiMiR has tools for automatic upload of the data from the microarray scanner and export to databases using MAGE-ML. CONCLUSION: MiMiR facilitates microarray data management, annotation and exchange, in line with international guidelines. The database is valuable for underpinning research activities and promotes a systematic approach to data handling. Copies of MiMiR are freely available to academic groups under licence.
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Interpretación Estadística de Datos , Bases de Datos Genéticas , Análisis de Secuencia por Matrices de Oligonucleótidos/instrumentación , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Programas Informáticos , Recolección de Datos , Presentación de Datos , Interfaz Usuario-ComputadorRESUMEN
Inherited immunodeficiency disorders can be caused by mutations in any one of a large number of genes involved in the function of immune cells. Here, we describe two families with an autosomal recessive inherited immunodeficiency disorder characterized by increased susceptibility to infection and autoimmunity. Genetic linkage studies mapped the disorder to chromosomal region 14q11.2, and a homozygous guanine-to-adenine substitution was identified at the last base of exon 3 immediately following the translational termination codon in the TCRα subunit constant gene (TRAC). RT-PCR analysis in the two affected individuals revealed impaired splicing of the mRNA, as exon 3 was lost from the TRAC transcript. The mutant TCRα chain protein was predicted to lack part of the connecting peptide domain and all of the transmembrane and cytoplasmic domains, which have a critical role in the regulation of the assembly and/or intracellular transport of TCR complexes. We found that T cells from affected individuals were profoundly impaired for surface expression of the TCRαß complex. We believe this to be the first report of a disease-causing human TRAC mutation. Although the absence of TCRαß+ T cells in the affected individuals was associated with immune dysregulation and autoimmunity, they had a surprising level of protection against infection.
Asunto(s)
Síndromes de Inmunodeficiencia/genética , Síndromes de Inmunodeficiencia/inmunología , Mutación , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Linfocitos T/inmunología , Secuencia de Bases , Preescolar , Análisis Mutacional de ADN , Células HeLa , Humanos , Datos de Secuencia Molecular , Linaje , Polimorfismo de Nucleótido Simple , Receptores de Antígenos de Linfocitos T alfa-beta/metabolismo , Linfocitos T/citologíaRESUMEN
Arthrogryposis, renal dysfunction and cholestasis syndrome (ARC) is a multisystem disorder associated with abnormalities in polarized liver and kidney cells. Mutations in VPS33B account for most cases of ARC. We identified mutations in VIPAR (also called C14ORF133) in individuals with ARC without VPS33B defects. We show that VIPAR forms a functional complex with VPS33B that interacts with RAB11A. Knockdown of vipar in zebrafish resulted in biliary excretion and E-cadherin defects similar to those in individuals with ARC. Vipar- and Vps33b-deficient mouse inner medullary collecting duct (mIMDC-3) cells expressed membrane proteins abnormally and had structural and functional tight junction defects. Abnormal Ceacam5 expression was due to mis-sorting toward lysosomal degradation, but reduced E-cadherin levels were associated with transcriptional downregulation. The VPS33B-VIPAR complex thus has diverse functions in the pathways regulating apical-basolateral polarity in the liver and kidney.