Bff38cab-b7f6-4d75-9517-0ba1c106bff3 - samples
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ABSTRACT:
PROVIDER: EGAD00001005062 | EGA |
REPOSITORIES: EGA
Similar Datasets
Project description:In order to screen potential novel 'driver genes' in lung cancer in Xuanwei (LCXW), genome-wide DNA copy number alterations (CNAs) were detected on 8 paired LCXW and non-cancerous lung (NCL) tissues by array-based comparative genomic hybridization microarrays. The log2 copy-number ratio calculation and CNA calls were determined using segMNT algorithm in NimbleScan. Log2 ratio test/control thresholds of 0.25 and -0.25 were defined as copy number gains and losses, respectively. Deviant signal intensity ratios involving 5 or more neighboring probes were considered as genomic aberrations. A large number of CNAs and DEGs were detected, respectively. Many recurrent CNAs were screened out, including gains at 5p15.33-p15.32, 5p15.1-p14.3 and 5p14.3-p14.2, and losses at 11q24.3, 21q21.1, 21q22.12-q22.13 and 21q22.2.
2016-10-22 | GSE89046 | GEO
Project description:Generating sufficient DNA for high-throughput genetic analysis has always been a challenge for clinical settings where the amount of source DNA is limited. Multiple displacement amplification (MDA) has been proposed as a promising candidate for such situations. Previous work with lower-resolution arrays confirmed the utility of single-cell MDA products for large-size (~30 Mb) genome variation screening. We tested the performance of single-cell MDA products on the SNP 6.0 arrays to examine the performance of single-cell MDA in SNP genotyping, copy number polymorphism, de novo copy number variation (CNV) and loss of heterozygosity (LOH) analysis. Our data show that for SNP genotyping, single-cell MDA did not obtain complete genome coverage or high sequence fidelity. For CNV calling, single-cell MDA introduced stochastic amplification artifacts in log2 ratio profiles, reducing the robustness of CNV calling; however, by adjusting smooth window size, it is still possible to analyze large chromosomal aberrations, and homozygous deletions as small as 500 kb can still be identified from the noisy log2 ratio profiles. Our results also suggest that even with a modified protocol (reduction of reaction volume, addition of a molecular crowding reagent, minimization of reaction time), single-cell MDA presented little improvement over the unmodified protocol, but by increasing the number of cells as template to 5–10 cells, SNP 6.0 array results comparable to those of 10 ng genomic DNA MDA could be obtained. Algorithms like PICNIC improved the CNV calling, suggesting that better algorithms can better utilize single-cell MDA array results.
2011-03-25 | GSE28132 | GEO
Project description:Generating sufficient DNA for high-throughput genetic analysis has always been a challenge for clinical settings where the amount of source DNA is limited. Multiple displacement amplification (MDA) has been proposed as a promising candidate for such situations. Previous work with lower-resolution arrays confirmed the utility of single-cell MDA products for large-size (~30 Mb) genome variation screening. We tested the performance of single-cell MDA products on the SNP 6.0 arrays to examine the performance of single-cell MDA in SNP genotyping, copy number polymorphism, de novo copy number variation (CNV) and loss of heterozygosity (LOH) analysis. Our data show that for SNP genotyping, single-cell MDA did not obtain complete genome coverage or high sequence fidelity. For CNV calling, single-cell MDA introduced stochastic amplification artifacts in log2 ratio profiles, reducing the robustness of CNV calling; however, by adjusting smooth window size, it is still possible to analyze large chromosomal aberrations, and homozygous deletions as small as 500 kb can still be identified from the noisy log2 ratio profiles. Our results also suggest that even with a modified protocol (reduction of reaction volume, addition of a molecular crowding reagent, minimization of reaction time), single-cell MDA presented little improvement over the unmodified protocol, but by increasing the number of cells as template to 5M-bM-^@M-^S10 cells, SNP 6.0 array results comparable to those of 10 ng genomic DNA MDA could be obtained. Algorithms like PICNIC improved the CNV calling, suggesting that better algorithms can better utilize single-cell MDA array results. Affymetrix SNP arrays were performed according to the manufacturer's directions on DNA extracted from cell line samples, and multiple displacement samples. Genotyping, Copy number and LOH analysis of Affymetrix SNP 6.0 arrays was performed for 3 samples of unamplified cell line genomic DNA, 2 samples of DNA obtained by multiple displacement amplification from 10ng genomic DNA, 3 single-cell multiple displacement amplification (MDA) products, single cell modified MDA amplification product, 5-cell modified MDA amplification product, 10-cell modified MDA amplification product.
2011-03-25 | E-GEOD-28132 | biostudies-arrayexpress
Project description:33 ETMR samples were genotyped using Illumina HumanOmni2.5M array. Hybridization and scanning was done according to the manufacturer's instructions (Illumina). Copy number (Log R) and B allele frequency estimates were obtained sing the Genotyping module (v1.9.4) in GenomeStudio v2011.1 (Illumina). Normalized and log2-transformed copy number measurements were imported from genomestudio and analysed using R package CopyNumber to identify segments with similar copy number.
| EGAD00010001667 | EGA
Project description:Copy number variations (CNVs) constitute the largest portion of the human genome variation. We determined a genome-wide high resolution SNP/CNV haplotype structure of Asians, by analyzing a collection of complete hydatidiform moles (CHMs) of Japanese, using high-density DNA arrays. CHMs are tissues carrying duplicated haploid genomes derived from single sperms, and are suitable material for the detection of CNVs, because they are expected to reveal greater signal to noise ratio in hybridization experiments. Also, the absence of heterozygosity ensures straightforward CNV interpretation without being bothered by overlapping CNV segments. We genotyped 100 CHM genomes using Affymetrix SNP 6.0 and Illumina 1M-duo, created a definitive haplotype map including 1.7 million SNPs and 2339 CNV region (CNVR) that is presented as D-HaploDB Phase 4.1.
2014-02-13 | GSE54948 | GEO
Project description:373 tumors were profiled for copy-number alterations with the high-resolution Agilent 244A aCGH Array. Tumor samples were assayed on Agilent Human Genome CGH 244A Microarrays with the intent of surveying the landscape of genomic alterations in 5 tumor types. Human male genomic DNA (Promega P/N G1471) was used as reference. Individual log2 ratios of background subtracted signal intensities were obtained from the Agilent Feature Extraction software version 9.5. The log2 ratios were centered to a median of zero and the resulting log2 ratio values for each probe were segmented using GLAD. All probes within the genomic bounds of a given GLAD-derived segment were given the mean copy number value of probes within that segment.
2010-07-29 | E-GEOD-20393 | biostudies-arrayexpress
Project description:We performed shallow whole genome sequencing (WGS) on circulating free (cf)DNA extracted from plasma or cerebrospinal fluid (CSF), and shallow WGS on the tissue DNA extracted from the biopsy in order to evaluate the correlation between the two biomaterials. After library construction and sequencing (Hiseq3000 or Ion Proton), copy number variations were called with WisecondorX.
2021-11-17 | E-MTAB-10548 | biostudies-arrayexpress
Project description:1 lung tumor was profiled for copy-number alterations with the high-resolution Agilent 244A aCGH Array. One lung tumor sample were assayed on the Agilent Human Genome CGH 244A Microarrays with the intent of comparing the genomic alterations reported by the array platform with those reported by high-thoughput sequencing. Human male genomic DNA (Promega P/N G1471) was used as reference. Individual log2 ratios of background subtracted signal intensities were obtained from the Agilent Feature Extraction software version 9.5. The log2 ratios were centered to a median of zero and the resulting log2 ratio values for each probe were segmented using GLAD. All probes within the genomic bounds of a given GLAD-derived segment were given the mean copy number value of probes within that segment.
2010-05-27 | E-GEOD-20574 | biostudies-arrayexpress
Project description:Structural and functional impacts of copy number variations (CNVs) on livestock genomes are not yet well understood. In this study, we have identified 1853 CNV regions (CNVRs) using population-scale sequencing data generated from 75 cattle of 8 breeds (Holstein, Angus, Jersey, Limousin, Romagnola, Brahman, Gir and Nelore). Individual genome sequence coverage ranged from 4 to 30 fold, with a mean of 11.8 fold. A total of 3.1% (87.5 Mb) of the cattle genome is predicted to be copy number variable, representing a substantial increase over the previous estimates (~2%). This dataset was highly correlated with array CGH data (r2 = 0.761) and was validated to be accurate with an estimated 12% false positive rate and a 19% false negative rate based on qPCR and array CGH, respectively. Hundreds of CNVs were found to be either breed specific or differentially variable across breeds, including the RICTOR gene in dairy breeds and the PNPLA3 gene in the beef breeds. In contrast, clusters of the PRP and PAG genes are duplicated in all sequenced animals, implicating that subfunctionalization, neofunctionalization or overdominance play a role in diversifying these fertility related genes. Further population-genetic analyses based on CNVs revealed the population structures of these taurine and indicine breeds and uncovered hundreds of positively selected CNV candidates near important functional genes. These CNV results provide a new glimpse of diverse selections during cattle speciation, domestication, breed formation, and recent genetic improvement. 25 animals were analyzed using a custom Nimblegen aCGH chip with 2.1 million probes. The reference animal chosen was L1 Dominette, a Hereford cow of European ancestry. The array was subjected to a dye-swap with the reference sample to test probe intensity fidelity. Single channel intensity data from the array was used in a digital aCGH analysis to compare aCGH copy number estimates to copy number estimates derived from sequence data. Briefly, the reference signal from all analyzed arrays was collected and a median signal intensity was calculated from probe intensities within the BTF3 gene. The copy number of the reference animal was then inferred by division of single channel probe intensities with the median intensity of the BTF3 gene. Next, test sample intensities were normalized by taking the log2 ratio of the test intensity divided by the normalized reference copy number for the probe. CN values derived from sequence data were also normalized in this fashion by taking the log2 of the ratio of NGS CN divided by aCGH reference copy number.
2015-11-04 | E-GEOD-62990 | biostudies-arrayexpress
Project description:Diagnosis of glioma into the hierarchy of human brain development would greatly facilitate mechanistic studies and clinical services in combating glioma. By analysing the multi-dimension big data of glioma genome and clinical manifestations, we have recently developed an EM/PM classification scheme anchored in the brain development and glioma pathogenesis (Sun et al., PNAS 111:3538-3543, 2014). To translate the EM/PM classification into a clinical diagnostic tool, we here designed and validated a TaqMan low-density RT-PCR array (TLDA) and a support vector machine (SVM) based prediction model that enables individual diagnosis of gliomas into the EM/PM subtype with high accuracy and precision. Results of 153 individually diagnosed adult diffuse gliomas of WHO grades II-IV derived from Chinese or Swedish patients confirmed our previous data base investigations: EM and PM gliomas show distinct prognosis, occur at different ages, and harbor mutually exclusive patterns of genomic alterations detected by Sanger sequencing and shallow-coverage whole genome sequencing (WGS). Further, we show that shallow-coverage WGS enabled a systematic identification of clonal and subclonal copy number variations (CNV) in glioma genomes, and the extent and the pattern of CNV can serve as an objective marker of tumor progression in the PM gliomas harboring IDH mutations.
2019-05-16 | GSE131273 | GEO