Search results for "gene mutation"
showing 10 items of 187 documents
Somatic loss of an EXT2 gene mutation during malignant progression in a patient with hereditary multiple osteochondromas
2015
Multiple osteochondromas (MO) is an autosomal-dominant skeletal disorder caused by mutations in the exostosin-1 ( EXT1 ) or exostosin-2 ( EXT2 ) genes. In this study, we report the analysis of the mutational status of the EXT2 gene in tumor samples derived from a patient affected by hereditary MO, documenting the somatic loss of the germline mutation in a giant chondrosarcoma and in a rapidly growing osteochondroma. The sequencing of all exons and exon–intron junctions of the EXT1 and EXT2 genes from blood DNA of the proband did not reveal any mutation in the EXT1 gene but did demonstrate the presence of the transition point mutation c.67C > T in the EXT2 gene, determining the introduction …
Novel <b><i>VANGL1</i></b> Gene Mutations in 144 Slovakian, Romanian and German Patients with Neural Tube Defects
2012
Neural tube defects (NTDs) are a group of congenital malformations of the central nervous system occurring at an average rate of 1 per 1,000 human pregnancies worldwide. Numerous genetic and environmental factors are discussed to be relevant in their etiology. In mice, mutants in >200 genes including the planar cell polarity (PCP) pathway are known to cause NTDs, and recently, heterozygous mutations in the human <i>VANGL1</i> gene have been described in a small subset of patients with NTDs. We performed a <i>VANGL1</i> mutation analysis in 144 unrelated individuals with NTDs from Slovakia, Romania and Germany and identified 3 heterozygous missense mutations: c.613…
A New Mutation of the p53 Gene in Human Neuroblastoma, Not Correlated with N-myc Amplification
1999
N-myc gene amplification and/or loss of heterozygosity of chromosome 1 (LOH lp) are important criteria for prognosis and progression in human neuroblastoma (NB). Despite the high incidence of alterations of the p53 gene in human cancers, very few p53 mutations have been reported in NB. The objective of our study was to search for p53 mutations in NB and their correlation with N-myc amplification and clinical or pathologic parameters. We analyzed 14 selected cases of NB from the Spanish Protocol N-II-92. We found a missense mutation in codon 248 CGG to GGG (Arg/Gly) in one case of stage 4 NB with no N-myc amplification. Our results confirm the low incidence of p53 gene mutation in neuroblas…
A human CCT5 gene mutation causing distal neuropathy impairs hexadecamer assembly in an archaeal model
2014
Chaperonins mediate protein folding in a cavity formed by multisubunit rings. The human CCT has eight non-identical subunits and the His147Arg mutation in one subunit, CCT5, causes neuropathy. Knowledge is scarce on the impact of this and other mutations upon the chaperone's structure and functions. To make progress, experimental models must be developed. We used an archaeal mutant homolog and demonstrated that the His147Arg mutant has impaired oligomeric assembly, ATPase activity, and defective protein homeostasis functions. These results establish for the first time that a human chaperonin gene defect can be reproduced and studied at the molecular level with an archaeal homolog. The major…
Detection of mammalian carcinogens with an immunological DNA synthesis-inhibition test.
1992
There is a close relationship between genotoxicity, mutagenicity and carcinogenicity. But the controversy of which short-term test system best recognizes human carcinogens is still going on. Currently, the Salmonella gene mutation assay ('Ames test') is the most widely used test for the screening of mutagens. However, many in vitro tests hold unsatisfactory validity data, presumably because of the inability of present short-term tests to detect non-genotoxic carcinogens, which are increasingly being brought into focus in the discussions of genesis of cancer. One principle often neglected in this context is the property of genotoxic agents to inhibit replicative DNA synthesis in (proliferati…
Prenatal diagnosis and carrier detection in mucopolysaccharidosis type II by mutation analysis. A 47,XXY male heterozygous for a missense point mutat…
1994
Identification of iduronate-2-sulphatase (IDS) gene mutations in patients with mucopolysaccharidosis type II (MPS II, Hunter syndrome) allows fast and reliable carrier detection and prenatal diagnosis. We describe here three cases of prenatal diagnosis by direct detection of the gene mutation. In addition to two affected male fetuses from two different families, a 47,XXY fetus carrying both the normal and the mutant allele was diagnosed in a third family. The latter pregnancy was carried to term and the child is obviously not affected by MPS II.
Familial HDL deficiency due to ABCA1 gene mutations with or without other genetic lipoprotein disorders
2004
Mutations in ABCA1 have been shown to be the cause of Tangier disease (TD) and some forms of familial hypoalphalipoproteinemia (HA), two genetic disorders characterized by low plasma HDL levels. Here we report six subjects with low HDL, carrying seven ABCA1 mutations, six of which are previously unreported. Two mutations (R557X and H160FsX173) were predicted to generate short truncated proteins; two mutations (E284K and Y482C) were located in the first extracellular loop and two (R1901S and Q2196H) in the C-terminal cytoplasmic domain of ABCA1. Two subjects found to be compound heterozygotes for ABCA1 mutations did not have overt clinical manifestations of TD. Three subjects, all with prema…
Phenotype/Genotype Relationship in Left Ventricular Noncompaction: Ion Channel Gene Mutations Are Associated With Preserved Left Ventricular Systolic…
2021
International audience; Background: Few data exist concerning genotype-phenotype relationships in left ventricular noncompaction (LVNC).Methods and results: From a multicenter French Registry, we report the genetic and clinical spectrum of 95 patients with LVNC, and their genotype-phenotype relationship. Among the 95 LVNC, 45 had at least 1 mutation, including 14 cases of mutation in ion channel genes. In a complementary analysis including 16 additional patients with ion channel gene mutations, for a total of 30 patients with ion channel gene mutation, we found that those patients had higher median LV ejection fraction (60% vs 40%; P < .001) and more biventricular noncompaction (53.1% vs 18…
Heterozygous nonsense SCN5A mutation W822X explains a simultaneous sudden infant death syndrome.
2008
The sudden, unexpected, and unexplained death of both members of a set of healthy twins (simultaneous sudden infant death syndrome (SSIDS)) is defined as a case in which both infants meet the definition of sudden infant death syndrome individually. A search of the world medical literature resulted in only 42 reported cases of SSIDS. We report the case of a pair of identical, male, monozygotic twins, 138 days old, who suddenly died, meeting the full criteria of SSIDS and where a genetic screen was performed, resulting in a heterozygous nonsense SCN5A mutation (W822X) in both twins. Immunohistochemistry was performed on cardiac tissue samples utilizing polyclonal antibodies anti-Na+ CP type V…
Cetuximab in small bowel adenocarcinoma: a new friend?
2010
Sir, Small bowel adenocarcinoma (SBA) is a rare and aggressive tumour. SBA in the United States increased from 5.7 cases per million in 1973 to 7.3 cases per million in 2004 (Surveillance Epidemiology and End Results (SEER), 1973–2004 database; Jemal et al (2009). Surgery is the mainstay of treatment, even if chemotherapy in advanced disease has been associated with an increased survival. The most effective agents include 5-FU, irinotecan, platinum agents and gemcitabine (Fishman et al, 2006; Speranza et al, 2010). The molecular characterisation of this cancer could help to improve prognosis. Specifically, the frequency of KRAS gene mutations is similar than in colorectal cancer (Ari et al,…