Search results for "Strand"
showing 10 items of 222 documents
Detection of three rare (G377S, T134P and 1451delAC), and two novel mutations (G195W and Rec[1263del55;1342G>C] in Spanish Gaucher disease patients
1999
To study glucocerebrosidase mutations causing Gaucher disease, we have screened 30 apparently unrelated patients for the presence of 7 previous described mutations. N370S (1226A>G) was the most common mutation (43%), followed by L444P (1448T>C) (23%). To identify the other unknown mutations, we screened regions of the glucocerebrosidase gene (GBA), by SSCP and sequencing. These analyses allowed identification of one novel G195W (700G>T), and two rare T134P (517A>C) and G377S (1246G>A) missense mutations. Mutation T134P (517A>C) was present in a type I patient, while G195W (700G>T), was encountered in two patients (types I, and III). The prevalence of mutation G377S (1246G>A), previously und…
Analysis ofBRCA1andBRCA2genes in Spanish breast/ovarian cancer patients: A high proportion of mutations unique to Spain and evidence of founder effec…
2003
We screened index cases from 410 Spanish breast/ovarian cancer families and 214 patients (19 of them males) with breast cancer for germ-line mutations in the BRCA1 and BRCA2 genes, using SSCP, PTT, CSGE, DGGE, and direct sequencing. We identified 60 mutations in BRCA1 and 53 in BRCA2. Of the 53 distinct mutations observed, 11 are novel and 12 have been reported only in Spanish families (41.5%). The prevalence of mutations in this set of families was 26.3%, but the percentage was higher in the families with breast and ovarian cancer (52.1%). The lowest proportion of mutations was found in the site-specific female breast cancer families (15.4%). Of the families with male breast cancer cases, …
Systematic screening for mutations in the promoter and the coding region of the 5-HT1A gene.
1995
In the present study we sought to identify genetic variation in the 5-HT{sub 1A} receptor gene which through alteration of protein function or level of expression might contribute to the genetic predisposition to neuropsychiatric diseases. Genomic DNA samples from 159 unrelated subjects (including 45 schizophrenic, 46 bipolar affective, and 43 patients with Tourette`s syndrome, as well as 25 healthy controls) were investigated by single-strand conformation analysis. Overlapping PCR (polymerase chain reaction) fragments covered the whole coding sequence as well as the 5{prime} untranslated region of the 5-HT{sub 1A} gene. The region upstream to the coding sequence we investigated contains a …
Detection of a novel germline mutation in the von Hippel-Lindau tumour-suppressor gene by fluorescence-labelled base excision sequence scanning (F-BE…
1999
The von Hippel Lindau (VHL) syndrome is an inherited multi-tumour disorder characterised by clinical heterogeneity and high penetrance. The VHL gene has been shown to be a tumour-suppressor gene. A carrier of a germline mutation will be predisposed to a high variety of benign and malign tumours affecting different organ systems. As treatment of VHL malformations in presymptomatic stages will improve significantly the clinical outcome and the patient's quality of life, early and unambiguous detection of a germline mutation is mandatory. Direct sequencing especially of large genes might be laborious and time consuming. Therefore, most laboratories apply single strand conformational polymorphi…
Mutational fitness effects in RNA and single-stranded DNA viruses: common patterns revealed by site-directed mutagenesis studies
2010
The fitness effects of mutations are central to evolution, yet have begun to be characterized in detail only recently. Site-directed mutagenesis is a powerful tool for achieving this goal, which is particularly suited for viruses because of their small genomes. Here, I discuss the evolutionary relevance of mutational fitness effects and critically review previous site-directed mutagenesis studies. The effects of single-nucleotide substitutions are standardized and compared for five RNA or single-stranded DNA viruses infecting bacteria, plants or animals. All viruses examined show very low tolerance to mutation when compared with cellular organisms. Moreover, for non-lethal mutations, the me…
Sequence, molecular organization and products of the Drosophila virilis homologs of the D. melanogaster nested genes lethal(2)tumorous imaginal discs…
1997
Abstract In this study, we describe the isolation of the Drosophila virilis (Dvir) 6201-bp genomic fragment homologous to a 7047-bp genomic region of D. melanogaster (Dmel) that harbors the nested genes lethal(2)tumorous imaginal discs (l(2)tid), lethal(2)neighbour of tid (l(2)not) and lethal(2)relative of tid (l(2)rot). The isolated fragment, which maps at the cytogenetic position 50A5 on chromosome 5, carries the Dvir homologs of the Dmel genes l(2)tid and l(2)not. In both cases, the interspecific comparison of the determined sequences reveals a high homology regarding the protein coding regions and a high degree of evolutionary divergence concerning the intronic parts of the genes. In th…
The haplotype distribution of two genes of citrus tristeza virus is altered after host change or aphid transmission.
1999
Genetic variability of citrus tristeza virus (CTV) was studied using the haplotypes detected by single-strand conformation polymorphism (SSCP) analysis of genes p18 and p20 in six virus populations of two origins. The Spanish group included a CTV isolate and subisolates obtained by graft-transmission to different host species. The other included two subisolates aphid-transmitted from a single Japanese isolate. The homozygosity observed for gene p20 was always significantly higher than that expected under neutral evolution, whereas only three populations showed high homozygosity for p18, suggesting stronger host constraints for p20 than for p18. Sequential transmissions of a Spanish isolate …
TP53 mutations and S-phase fraction but not DNA-ploidy are independent prognostic indicators in laryngeal squamous cell carcinoma
2005
ToprospectivelyevaluatetheprognosticsignificanceofTP53,H-,K-,andN-Rasmutations,DNA-ploidyandS-phasefraction(SPF) in patients affected by locally advanced laryngeal squamous cell carcinoma (LSCC). Eight-one patients (median follow-up was 71 months) who underwent resective surgery for primary operable locally advanced LSCC were analyzed. Tumor DNA was screened for mutational analysis by PCR/SSCP and sequencing. DNA-ploidy and SPF were performed byflow cytometric analyses. Thirty-six patients (44%) had, at least, a mutation in the TP53 gene. Of them, 22% (8/36) had double mutations and 3% (1/36) had triplemutations.Intotal,46TP53mutationswereobserved.Themajority(41%)oftheseoccurinexon5(19/46),…
High resistance to X-rays and therapeutic carbon ions in glioblastoma cells bearing dysfunctional ATM associates with intrinsic chromosomal instabili…
2014
To investigate chromosomal instability and radiation response mechanisms in glioblastoma cells.We undertook a comparative analysis of two patient-derived glioblastoma cell lines. Their resistance to low and high linear energy transfer (LET) radiation was assessed using clonogenic survival assay and their intrinsic chromosome instability status using fluorescence in situ hybridization. DNA damage was analyzed by pulsed-field gel electrophoresis and by γ-H2AX foci quantification. Expression of DNA damage response proteins was assessed by immunoblot.Increased radioresistance to X-rays as well as carbon ions was observed in glioblastoma cells exhibiting high levels of naturally occurring chromo…
Genetic analysis of 2299delG and C759F mutations (USH2A) in patients with visual and/or auditory impairments
2004
The most common mutation in the USH2A gene (Usherin), 2299delG, causes both typical Usher (USH) syndrome type II and atypical USH syndrome, two autosomal recessive disorders, characterised by moderate to severe sensorineural hearing loss and retinitis pigmentosa (RP). Furthermore, the C759F mutation in the USH2A gene has been described in 4.5% of patients with nonsyndromic recessive RP. We have investigated the presence of the 2299delG and/or the C759F mutations in 191 unrelated Spanish patients with different syndromic and nonsyndromic retinal diseases, or with nonsyndromic hearing impairment. The 2299delG mutation was observed in patients with clinical signs of USHII or of atypical USH sy…