Nanopore sequencing from liquid biopsy: analysis of copy number variations from cell-free DNA of lung cancer patients
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PROVIDER: EGAS00001004975 | EGA |
REPOSITORIES: EGA
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Project description:Cancer is a DNA disease characterized by the presence of genetics alterations in cancer cells.
The recent studies underline that these recurring alterations must be considered as a good molecular marker. In fact, they could use for tumor DNA detection in different biological fluids.
So, the main purpose is to define the presence of circulating tumor DNA in the patients plasma with colorectal cancer, by the presence of mutation (KRAS, NRAS, BRAF, APC, TP53 and MIRCOSATELLIE instability).
These molecular analysis will be done both in tumor and plasma samples,
This trial allows to characterize the prognostic value of circulating tumoral DNA presence in colorectal cancer.
| 2094858 | ecrin-mdr-crc
Project description:Gene copy number variations (CNVs) involved in phenotypic variations have already been shown in plants, but genome-wide testing of CNVs for adaptive variation was not doable until recent technological developments. Thus, reports of the genomic architecture of adaptation involving CNVs remain scarce to date. Here, we investigated F1 progenies of an intra-provenance cross (north-north cross, 58th parallel) and an inter-provenances cross (north-south cross, 58th/49th parallels) for CNVs using comparative genomic hybridization on arrays of probes targeting gene sequences in balsam poplar (Populus balsamifera L.), a wide-spread North American forest tree. Results: A total of 1,721 genes were found in varying copy numbers over the set of 19,823 tested genes. These gene CNVs presented an estimated average size of 8.3 kb and were distributed over poplar’s 19 chromosomes including 22 hotspot regions. Gene CNVs number was higher for the inter-provenance progeny in accordance with an expected higher genetic diversity related to the composite origin of this family. Regression analyses between gene CNVs and seven adaptive trait variations resulted in 23 significant links; among these adaptive gene CNVs, 30% were located in hotspots. One-to-five gene CNVs were found related to each of the measured adaptive traits and annotated for both biotic and abiotic stress responses. These annotations can be related to the occurrence of a higher pathogenic pressure in the southern parts of balsam poplar’s distribution, and higher photosynthetic assimilation rates and water-use efficiency at high-latitudes. Overall, our findings suggest that gene CNVs typically having higher mutation rates than SNPs, may in fact represent efficient adaptive variations against fast-evolving pathogens.
2018-09-11 | GSE119764 | GEO
Project description:Chromosomal segmental copy number variation (CNV) has been recently recognized as a very important source of genetic variability. Some CNV loci involve genes or conserved regulatory regions. Compelling evidence indicates that CNVs impact genome functions. The chicken is a very important farm animal species which has also served as model animal for biological and biomedical research for hundreds of years. A map of CNVs in chickens could facilitate the identification of chromosome regions that segregate for important agricultural and disease phenotypes. NimbleGen 385k whole genome tiling arrays were used to map CNVs in the chicken. This study has identified 96 CNVs in three lines of chickens (broiler, Leghorn and Rhode Island red). These CNVs encompass 16 Mb (1.3%) of the chicken genome. Twenty six CNVs were found in two or more animals. Smaller sized CNVs mostly affect none coding sequences while larger CNV regions involve genes, for example prolactin receptor, aldose reductase and zinc finger proteins, suggesting chicken CNVs potentially affect agricultural or disease related traits. Blood DNA isolated from Cornish Rock, Leghorn and Rhode Island Red birds. Cy5 labeled DNA from a Cornish Rock male used as reference was mixed with Cy3 labeled DNA samples was then hybridized to the 385K chicken tiling array. Fluorescence intensity data were normalized with qspline algorithm and ratio data were analyzed with the circular binary segmentation algorithm from Olshen et al. Copy number variation calls were made if the averaged Log2 ratio of a segment was shifted by 0.3 from the baseline.
2010-06-11 | E-GEOD-19469 | biostudies-arrayexpress
Project description:Copy Number Variations (CNVs) were identified performing Comparative Genomic Hybridization (CGH) on 225 patients after whole-genome amplification, using Agilent SurePrint G3 4x180K microarrays. CNVs were further integrated with gene expression (Affymetrix U133+2 arrays) and mutations (targeted DNA resequencing). Complete description of the methods, array quality checks and called segments are available as supplemental material in the corresponding publication.
2019-10-24 | GSE136962 | GEO
Project description:Copy number variations (CNVs) can create new genes, change gene dosage, reshape gene structures, and modify elements regulating gene expression. As with all types of genetic variation, CNVs may influence phenotypic variation and gene expression. CNVs are thus considered major sources of genetic variation. Little is known, however, about their contribution to genetic variation in rice. To detect CNVs, we used a set of NimbleGen whole-genome comparative genomic hybridization arrays containing 715,851 oligonucleotide probes with a median probe spacing of 500 bp. We compiled a high-resolution map of CNVs in the rice genome, showing 641 CNVs between the genomes of the rice cultivars M-bM-^@M-^XNipponbareM-bM-^@M-^Y (from O. sativa ssp. japonica) and M-bM-^@M-^XGuang-lu-ai 4M-bM-^@M-^Y (from O. sativa ssp. indica). These CNVs contain some known genes. They are linked to variation among rice varieties, and are likely to contribute to subspecific characteristics. Genomic DNA isolated from Nipponbare and Guang-lu-ai 4. Cy5 labeled DNA from Nipponbare used as reference and Cy3 labeled DNA from Guang-lu-ai 4 was hybridized to the 720K rice tiling array including three replicates. Fluorescence intensity data were normalized with qspline algorithm and ratio data were analyzed with the circular binary segmentation algorithm. Copy number variation calls were made if the averaged Log2 ratio of a segment was shifted by 1.0 from the baseline.
2012-06-30 | E-GEOD-30542 | biostudies-arrayexpress
Project description:We describe a more detailed survey undertaken to detect candidate CNVs in a panel of 20 Asian cultivated rice and the genome-wide characteristics of CNVs in subspecies and groups. These resources allowed us to analyze genetic structure as indicated by CNVs, to implicate the biological roles of CNVs, and to identify candidate CNVs that are likely to occur independently in groups and contribute to differences between the subspecies.
2014-01-01 | GSE42769 | GEO
Project description:Chromosomal segmental copy number variation (CNV) has been recently recognized as a very important source of genetic variability. Some CNV loci involve genes or conserved regulatory regions. Compelling evidence indicates that CNVs impact genome functions. The chicken is a very important farm animal species which has also served as model animal for biological and biomedical research for hundreds of years. A map of CNVs in chickens could facilitate the identification of chromosome regions that segregate for important agricultural and disease phenotypes. NimbleGen 385k whole genome tiling arrays were used to map CNVs in the chicken. This study has identified 96 CNVs in three lines of chickens (broiler, Leghorn and Rhode Island red). These CNVs encompass 16 Mb (1.3%) of the chicken genome. Twenty six CNVs were found in two or more animals. Smaller sized CNVs mostly affect none coding sequences while larger CNV regions involve genes, for example prolactin receptor, aldose reductase and zinc finger proteins, suggesting chicken CNVs potentially affect agricultural or disease related traits.
2010-06-11 | GSE19469 | GEO
Project description:It has been shown that the human genome contains extensive copy number variations (CNVs). Investigating the medical and evolutionary impacts of CNVs requires the knowledge of locations, sizes and frequency distribution of CNVs within and between populations. However, CNV study of Chinese populations has been underrepresented considering the same efforts in other populations. Here we constructed a Chinese CNV map by using Affymetrix SNP 6 array. We did population analysis with other HapMap populations and identified population specific CNVs as well as candidate CNV regions under selection. Our results serve as a useful resource in further evolutionary and medical studies.
2011-12-31 | GSE30481 | GEO
Project description:Copy number variations (CNVs) can create new genes, change gene dosage, reshape gene structures, and modify elements regulating gene expression. As with all types of genetic variation, CNVs may influence phenotypic variation and gene expression. CNVs are thus considered major sources of genetic variation. Little is known, however, about their contribution to genetic variation in rice. To detect CNVs, we used a set of NimbleGen whole-genome comparative genomic hybridization arrays containing 715,851 oligonucleotide probes with a median probe spacing of 500 bp. We compiled a high-resolution map of CNVs in the rice genome, showing 641 CNVs between the genomes of the rice cultivars ‘Nipponbare’ (from O. sativa ssp. japonica) and ‘Guang-lu-ai 4’ (from O. sativa ssp. indica). These CNVs contain some known genes. They are linked to variation among rice varieties, and are likely to contribute to subspecific characteristics.
2012-07-01 | GSE30542 | GEO
Project description:Mounting evidence suggests that copy number variations (CNVs) can contribute to cancer susceptibility. The main goal of this study was to evaluate the role of germline CNVs in melanoma predisposition in high-risk melanoma families. We used genome-wide tiling comparative genomic hybridization and SNP arrays to characterize CNVs in 335 individuals (240 melanoma cases) from American melanoma-prone families (22 with germline CDKN2A or CDK4 mutations). We found that the global burden of overall CNVs (or deletions or duplications separately) was not significantly associated with case-control or CDKN2A/CDK4 mutation status after accounting for the familial dependence. However, we identified several rare CNVs that either involved known melanoma genes (e.g. PARP1, CDKN2A) or co-segregated with melanoma (duplication on 10q23.23, 3p12.2 and deletions on 8q424.3, 2q22.1) in families without mutations in known melanoma high-risk genes. Some of these CNVs were correlated with expression changes in disrupted genes based on RNASeq data from a subset of melanoma cases included in the CNV study. These results suggest that rare co-segregating CNVs may influence melanoma susceptibility in some melanoma-prone families and genes found in our study warrant further evaluation in future genetic analyses of melanoma.
2016-12-01 | GSE85010 | GEO