Search results for "gene duplication"

Duplicated cytoglobin genes in teleost fishes

2005

Cytoglobin is a recently discovered myoglobin-related O2-binding protein of vertebrates with uncertain function. It occurs as single-copy gene in mammals. Here, we demonstrate the presence of two paralogous cytoglobin genes (Cygb-1 and Cygb-2) in the teleost fishes Danio rerio, Oryzias latipes, Tetraodon nigroviridis, and Takifugu rubripes. The globin-typical introns at positions B12.2 and G7.0 are conserved in both genes, whereas the C-terminal exon found in mammalian cytoglobin is absent in the fish genes. Phylogenetic analyses show that the two cytoglobin genes diverged early in teleost evolution. This is confirmed by gene synteny analyses, which suggest a large-scale duplication event. …

Four unrelated patients with lubs X-linked mental retardation syndrome and different Xq28 duplications

2010

The Lubs X-linked mental retardation syndrome (MRXSL) is caused by small interstitial duplications at distal Xq28 including the MECP2 gene. Here we report on four novel male patients with MRXSL and different Xq28 duplications delineated by microarray-based chromosome analysis. All mothers were healthy carriers of the duplications. Consistent with an earlier report [Bauters et al. (2008); Genome Res 18: 847-858], the distal breakpoints of all four Xq28 duplications were located in regions containing low-copy repeats (LCRs; J, K, and L groups), which may facilitate chromosome breakage and reunion events. The proximal breakpoint regions did not contain known LCRs. Interestingly, we identified …

In the literature: October 2016

2016

A consortium on clinical and molecular stratification on oesophageal adenocarcinoma established in Britain has recently published in Nature Genetics , a whole-genomic sequencing analysis of more than 100 samples.1 Interestingly, they describe three distinct molecular subtypes with potential treatment relevance. This observation has also been verified in an independent validation cohort. Those three types are: (1) the ones showing homologous recombination and chromosome segregation pathways defects with enrichment of a BRCA signature. These tumours would be sensitive to DNA damaging agents, including neutron and photon irradiation with the addition of PARP inhibitors, (2) a group with high m…

Array-CGH defined chromosome 1p duplication in a patient with autism spectrum disorder, mild mental deficiency, and minor dysmorphic features

2010

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…

In vitro evolution of an atrazine-degrading population under cyanuric acid selection pressure: Evidence for the selective loss of a 47kb region on th…

2011

International audience; The adaptation of microorganisms to pesticide biodegradation relies on the recruitment of catabolic genes by horizontal gene transfer and homologous recombination mediated by insertion sequences (IS). This environment-friendly function is maintained in the degrading population but it has a cost which could diminish its fitness. The loss of genes in the course of evolution being a major mechanism of ecological specialization, we mimicked evolution in vitro by sub-culturing the atrazine-degrading Pseudomonas sp. ADP in a liquid medium containing cyanuric acid as the sole source of nitrogen. After 120 generations, a new population evolved, which replaced the original on…

Balanced Gene Losses, Duplications and Intensive Rearrangements Led to an Unusual Regularly Sized Genome in Arbutus unedo Chloroplasts

2013

Completely sequenced plastomes provide a valuable source of information about the duplication, loss, and transfer events of chloroplast genes and phylogenetic data for resolving relationships among major groups of plants. Moreover, they can also be useful for exploiting chloroplast genetic engineering technology. Ericales account for approximately six per cent of eudicot diversity with 11,545 species from which only three complete plastome sequences are currently available. With the aim of increasing the number of ericalean complete plastome sequences, and to open new perspectives in understanding Mediterranean plant adaptations, a genomic study on the basis of the complete chloroplast geno…

Genotype-Phenotype Analysis across 130,422 Genetic Variants Identifies Rspo3 as the First Genome-Wide Significant Modifier Gene in Primary Sclerosing…

2016

Background Ulcerative colitis (UC), a complex polygenic disorder, is one of the main subphenotypes of inflammatory bowel disease. A comprehensive dissection of the genetic etiology of UC needs to assess the contribution of rare genetic variants including copy number variations (CNVs) to disease risk. In this study, we performed a multi-step genome-wide case-control analysis to interrogate the presence of disease-relevant rare copy number variants. Methods One thousand one hundred twenty-one German UC patients and 1770 healthy controls were initially screened for rare deletions and duplications employing SNP-array data. Quantitative PCR and high density custom array-CGH were used for validat…

Ileocecal duplication cysts: is the loss of the valve always necessary?

2014

Abstract Background Ileocecal (IC) duplication cysts are enteric duplications located at the IC junction, not clearly identified in all the published series. The reported treatment is IC resection and ileocolic anastomosis. It is well known that the loss of the IC valve has several adverse effects. This study is aimed at demonstrating that cyst removal together with the common ileal wall and following enterorrhaphy is possible, safe, and effective in preserving the IC region. Methods Medical records of 3 patients who underwent surgery for IC duplication between 2003 and 2013 were retrospectively reviewed evaluating follow-up results. Results All patients had an antenatal diagnosis of intraa…

Why are the genomes of endosymbiotic bacteria so stable?

2003

The comparative analysis of three strains of the endosymbiotic bacterium Buchnera aphidicola has revealed high genome stability associated with an almost complete absence of chromosomal rearrangements and horizontal gene transfer events during the past 150 million years. The loss of genes involved in DNA uptake and recombination in the initial stages of endosymbiosis probably underlies this stability. Gene loss, which was extensive during the initial steps of Buchnera evolution, has continued in the different Buchnera lineages since their divergence.