Search results for "MUTATION"
showing 10 items of 2830 documents
Search for a gene responsible for Floating-Harbor syndrome on chromosome 12q15q21.1.
2012
International audience; Floating-Harbor syndrome (FHS) is characterized by characteristic facial dysmorphism, short stature with delayed bone age, and expressive language delay. To date, the gene(s) responsible for FHS is (are) unknown and the diagnosis is only made on the basis of the clinical phenotype. The majority of cases appeared to be sporadic but rare cases following autosomal dominant inheritance have been reported. We identified a 4.7 Mb de novo 12q15-q21.1 microdeletion in a patient with FHS and intellectual deficiency. Pangenomic 244K array-CGH performed in a series of 12 patients with FHS failed to identify overlapping deletions. We hypothesized that FHS is caused by haploinsuf…
Not All Floating-Harbor Syndrome Cases are Due to Mutations in Exon 34 of SRCAP
2013
International audience; Floating-Harbor syndrome (FHS) is a rare disorder characterized by short stature, delayed bone age, speech delay, and dysmorphic facial features. We report here the molecular analysis of nine cases, fulfilling the diagnostic criteria for FHS. Using exome sequencing, we identified SRCAP as the disease gene in two cases and subsequently found SRCAP truncating mutations in 6/9 cases. All mutations occurred de novo and were located in exon 34, in accordance with the recent report of Hood et al. However, the absence of SRCAP mutations in 3/9 cases supported genetic heterogeneity of FH syndrome. Importantly, no major clinical differences were observed supporting clinical h…
Selection of a precore mutant after vertical transmission of different hepatitis B virus variants is correlated with fulminant hepatitis in infants
1995
The incidence of perinatal transmission of hepatitis B virus (HBV) depends on the HBeAg/anti-HBe status of the mother. While children of HBeAg-positive mothers have a 90% probability of acquiring a chronic hepatitis B virus carrier state, babies of anti-HBe-positive mothers are more likely to develop fulminant hepatitis within the first 3 to 4 months of life. There is evidence that precore (pre-C) mutations of the HBV can be associated with fulminant hepatitis. The pre-C region was therefore examined in sera from nine infants with fulminant hepatitis after vertical transmission, one HBeAg-positive and seven anti-HBe-positive mothers by polymerase chain reaction (PCR) and direct sequence ana…
Clonal heterogeneity of thymic B cells from early-onset myasthenia gravis patients with antibodies against the acetylcholine receptor
2014
Myasthenia gravis (MG) with antibodies against the acetylcholine receptor (AChR-MG) is considered as a prototypic autoimmune disease. The thymus is important in the pathophysiology of the disease since thymus hyperplasia is a characteristic of early-onset AChR-MG and patients often improve after thymectomy. We hypothesized that thymic B cell and antibody repertoires of AChR-MG patients differ intrinsically from those of control individuals. Using immortalization with Epstein Barr Virus and Toll-like receptor 9 activation, we isolated and characterized monoclonal B cell lines from 5 MG patients and 8 controls. Only 2 of 570 immortalized B cell clones from MG patients produced antibodies agai…
Fragile-X carrier females: evidence for a distinct psychopathological phenotype?
1996
The present study examined 35 mothers (29 premutation carriers) of children with fragile-X syndrome in measures of intelligence and psychiatric disorders by comparing them with two control groups: a) 30 mothers of children in the general population and b) 17 mothers of non-fra-X retarded children with autism. Premutation carriers had a higher frequency of affective disorders than mothers from the general population. Preliminary data indicate that normally intelligent premutation carriers of the fra-X genetic abnormality have a similar frequency of affective disorders (DSM-III-R criteria [APA, 1987]) than mothers of autistic children. Neither carriers of the premutation nor carriers of the f…
Genotype and phenotype analysis of Friedreich's ataxia compound heterozygous patients
2000
Friedreich's ataxia is caused by mutations in the FRDA gene that encodes frataxin, a nuclear-encoded mitochondrial protein. Most patients are homozygous for the expansion of a GAA triplet repeat within the FRDA gene, but a few patients show compound heterozygosity for a point mutation and the GAA-repeat expansion. We analyzed DNA samples from a cohort of 241 patients with autosomal recessive or isolated spinocerebellar ataxia for the GAA triplet expansion. Patients heterozygous for the GAA expansion were screened for point mutations within the FRDA coding region. Molecular analyses included the single-strand conformation polymorphism analysis, direct sequencing, and linkage analysis with FR…
No Association between Mannose-Binding Lectin Alleles and Susceptibility to Chronic Hepatitis B Virus Infection in German Patients
1998
Variants of the mannose-binding lectin (MBL) have been shown to be associated with low serum concentrations of the protein and to predispose to bacterial, fungal and viral infections. A recent small study on 33 Caucasian patients had suggested that a mutation at codon 52 of the MBL gene is associated with chronic hepatitis B virus (HBV) infection. Exon 1 of the MBL gene was amplified by PCR in 61 patients with chronic HBV infection, 28 patients with acute infection and in 60 controls. MBL variants were detected by subsequent restriction enzyme digestion and agarose gel electrophoresis. The occurrence of the codon 52 mutation in patients with chronic HBV infection did not differ significantl…
The behaviour of Bcl-2, Bax and Bcl-x in Darier's disease
2002
SummaryBackground Darier's disease (DD) is a rare autosomal dominant disorder of keratinization caused by a mutation of the ATP2A2 gene. There is little information on the behaviour of Bcl-2, Bax and Bcl-x in DD. Objectives To investigate the dynamic control and the behaviour of Bax, Bcl-2 and Bcl-x in DD. We asked whether members of the Bcl-2 family might manifest their effects through modulation of intracellular calcium signalling or whether the gene that encodes the sarco/endoplasmic reticulum Ca2+ ATPase isoform 2 (SERCA2) modulates the Bcl-2 family in the regulation of apoptosis in DD. Methods Immunohistochemical methods were used. Results There was no immunoreactivity for Bcl-2 and Bc…
Inflammation, Longevity, and Cardiovascular Diseases: Role of Polymorphisms of TLR4
2006
The total burden of infection at various sites may affect the progression of atherosclerosis, the risk being modulated by host genotype. The role of lipopolysaccaride receptor TLR4 is paradigmatic. It initiates the innate immune response against gram-negative bacteria; and TLR4 polymorphisms, as ASP299GLY, suggested to attenuate receptor signaling, have been described. We demonstrated that TLR4 ASP299GLY polymorphism shows a significantly lower frequency in patients affected by myocardial infarction compared to controls, whereas centenarians show a higher frequency. Thus, people genetically predisposed to developing weak inflammatory activity, seem to have fewer chances of developing cardio…
HBV-DNA suppression and disease course in HBV cirrhosis patients on long-term lamivudine therapy
2005
In hepatitis B virus (HBV) cirrhosis patients on long-term lamivudine (LAM), the relationships between HBV suppression, development of viral resistance and disease outcome are unclear. We analysed the dynamic of serum HBV-DNA and its relationship with the clinical course of 59 patients (52 males, mean age 51.4 ±8.4 years, 12 HBeAg positive and 47 HBeAg negative, and 57 genotype D and two genotype A) with cirrhosis (45 in Child-Turcotte-Pugh class A) and high levels of serum HBV-DNA (median 14.7x107 genomes/ml) treated with LAM [median (range): 44 (15–78) months]. A total of 50 patients (84.7%) achieved a virological response (serum HBV-DNA negative by PCR) during the first 6 months of ther…