Search results for "X-linked"
showing 10 items of 65 documents
Novel form of X-linked nonsyndromic hearing loss with cochlear malformation caused by a mutation in the type IV collagen gene COL4A6
2013
Hereditary hearing loss is the most common human sensorineural disorder. Genetic causes are highly heterogeneous, with mutations detected in >40 genes associated with nonsyndromic hearing loss, to date. Whereas autosomal recessive and autosomal dominant inheritance is prevalent, X-linked forms of nonsyndromic hearing impairment are extremely rare. Here, we present a Hungarian three-generation family with X-linked nonsyndromic congenital hearing loss and the underlying genetic defect. Next-generation sequencing and subsequent segregation analysis detected a missense mutation (c.1771G>A, p.Gly591Ser) in the type IV collagen gene COL4A6 in all affected family members. Bioinformatic analysis an…
The aristaless (Arx) gene: one gene for many "interneuronopathies".
2009
The ARX (Aristaless-related (X-linked) homeobox) gene is not only present in arthropods and their ancestors, but also in vertebrates including humans (ARX orthologs). The gene is composed of 5 coding exons and it is expressed predominantly in foetal and adult brain and skeletal muscle. In this review we report on our experience and review the existing literature on the genotype and phenotype heterogeneity associated with ARX abnormalities in humans ranging from severe neuronal migration defects (e.g., lissencephaly), to mild forms of X-linked mental retardation without apparent brain abnormalities. The ARX-related disorders are reviewed focusing on their clinical features and on the role of…
A novel EDA variant causing X-linked hypohidrotic ectodermal dysplasia: Case report
2021
Abstract Hereditary ectodermal dysplasias are a complex group of inherited disorders characterised by abnormalities in two or more ectodermal derivatives (skin, nails, sweat glands, etc.). There are two main types of these disorders – hidrotic and hypohidrotic/anhidrotic ectodermal dysplasias. Hypohidrotic ectodermal dysplasia (HED) or Christ-Siemens-Touraine syndrome (OMIM: 305100 ) occurs in 1 out of 5000–10,000 births [19] and has an X-linked recessive inheritance pattern (X-linked hypohydrotic ectodermal dysplasia – XLHED) [2] . The main cause of XLHED is a broad range of pathogenic variants in the EDA gene (HGNC:3157, Xq12-13) which encodes the transmembrane protein ectodysplasin-A [4]…
Empirical mode decomposition and neural network for the classification of electroretinographic data
2013
The processing of biosignals is increasingly being utilized in ambulatory situations in order to extract significant signals' features that can help in clinical diagnosis. However, this task is hampered by the fact that biomedical signals exhibit a complex behaviour characterized by strong non-linear and non-stationary properties that cannot always be perceived by simple visual examination. New processing methods need be considered. In this context, we propose to apply a signal processing method, based on empirical mode decomposition and artificial neural networks, to analyse electroretinograms, i.e. the retinal response to a light flash, with the aim to detect and classify retinal diseases…
Broad spectrum of Fabry disease manifestation in an extended Spanish family with a new deletion in the GLA gene
2012
Background. Fabry disease (FD) is an X-linked inherited disease based on the absence or reduction of lysosomal-galactosidase (Gla) activity. The enzymatic defect results in progressive impairment of cerebrovascular, renal and cardiac function. Normally, female heterozygote mutation carriers are less strongly affected than male hemizygotes aggravating disease diagnosis. Method. Close examination of the patients by renal biopsy, echo- and electrocardiography and MRI. Blood work and subsequent DNA analysis were carried out utilizing approved protocols for PCR and Sequencing. MLPA analysis was done to unveil deletions within the GLA gene locus. Quantitative detection of Glycolipids in patient p…
Molecular and clinical characterization of a small duplication Xp in a human female with psychiatric disorders
2011
CGH techniques allow us to detect small duplications thatoccur in humans with phenotypic manifestations and demon-strate the importance of these duplications in the etiologyof neurodevelopmental impairment. As in the case of otherX-linked disorders, X-inactivation plays a major role in theclinical expression of such X chromosomal imbalances withusually milder symptoms in females than in males. Mostmale patients carrying Xp duplication have mental retarda-tion (X-linked mental retardation) and variable facial dys-morphic features (Gimelli
Congenital generalized hypertrichosis: the skin as a clue to complex malformation Syndromes.
2015
Hypertrichosis is defined as an excessive growth in body hair beyond the normal variation compared with individuals of the same age, race and sex and affecting areas not predominantly androgen-dependent. The term hirsutism is usually referred to patients, mainly women, who show excessive hair growth with male pattern distribution. Hypertrichosis is classified according to age of onset (congenital or acquired), extent of distribution (generalized or circumscribed), site involved, and to whether the disorder is isolated or associated with other anomalies. Congenital hypertrichosis is rare and may be an isolated condition of the skin or a component feature of other disorders. Acquired hypertri…
X-LINKED INTELLECTUAL DISABILITY
2013
The intellectual disability is found in approximately 2-3% of the population in a mild-to-moderate form and 0.5-1% in a moderate-to-severe form. The mutations on the chromosome X are responsible for both syndromic and non-syndromic intellectual disability. In the syndromic forms behavioral disorders, autism and/or seizures are frequent.
Rapid detection of an Angiotensin Type 2 Receptor Gene variant: no evidence for linkage and association with primary vesicoureteral reflux
2000
Primary vesicoureteral reflux (VUR) affects approximately 1−2% of the general population and is a common cause of end-stage renal failure in children. VUR appears to have a genetic basis and several loci including the Angiotensin Type 2 Receptor Gene (AGTR2) on the X chromosome have been suggested. Using single-strand conformation analysis (SSCA) we typed 103 DNA samples from 17 families with two or more affected individuals for the presence of a splice site mutation in the AGTR2 gene. Linkage analysis revealed a parametric LOD score of −3.977 and a NPL-score of −6,522 by affected-only analysis. Our family-data do not support linkage of VUR to the AGTR2.
Clinical, immunological, and molecular analysis in a large cohort of patients with X-linked agammaglobulinemia: an Italian multicenter study
2002
A questionnaire-based retrospective clinical and immunological survey was conducted in 73 males with a definite diagnosis of X-linked agammaglobulinemia based on BTK sequence analysis. Forty-four were sporadic and 29 familial cases. At December 2000, the patients' ages ranged from 2 to 33 years; mean age at diagnosis and mean duration of follow-up were 3.5 and 10 years respectively. After the mid-1980s all but 2 were on intravenous immunoglobulin (IVIG) substitution therapy, with residual IgG >500 mg/dl in 94% of the patients at the time of enrollment. Respiratory infections were the most frequent manifestation both prior to diagnosis and over follow-up. Chronic lung disease (CLD) was prese…