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Sample records for high copy numbers

  1. High-resolution copy number arrays in cancer and the problem of normal genome copy number variation.

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    Gorringe, Kylie L; Campbell, Ian G

    2008-11-01

    High-resolution techniques for analysis of genome copy number (CN) enable the analysis of complex cancer somatic genetics. However, the analysis of these data is difficult, and failure to consider a number of issues in depth may result in false leads or unnecessary rejection of true positives. First, segmental duplications may falsely generate CN breakpoints in aneuploid samples. Second, even when tumor data were each normalized to matching lymphocyte DNA, we still observed copy number polymorphisms masquerading as somatic alterations due to allelic imbalance. We investigated a number of different solutions and determined that evaluating matching normal DNA, or at least using locally derived normal baseline data, were preferable to relying on current online databases because of poor cross-platform compatibility and the likelihood of excluding genuine small somatic alterations.

  2. High resolution measurement of DUF1220 domain copy number from whole genome sequence data.

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    Astling, David P; Heft, Ilea E; Jones, Kenneth L; Sikela, James M

    2017-08-14

    DUF1220 protein domains found primarily in Neuroblastoma BreakPoint Family (NBPF) genes show the greatest human lineage-specific increase in copy number of any coding region in the genome. There are 302 haploid copies of DUF1220 in hg38 (~160 of which are human-specific) and the majority of these can be divided into 6 different subtypes (referred to as clades). Copy number changes of specific DUF1220 clades have been associated in a dose-dependent manner with brain size variation (both evolutionarily and within the human population), cognitive aptitude, autism severity, and schizophrenia severity. However, no published methods can directly measure copies of DUF1220 with high accuracy and no method can distinguish between domains within a clade. Here we describe a novel method for measuring copies of DUF1220 domains and the NBPF genes in which they are found from whole genome sequence data. We have characterized the effect that various sequencing and alignment parameters and strategies have on the accuracy and precision of the method and defined the parameters that lead to optimal DUF1220 copy number measurement and resolution. We show that copy number estimates obtained using our read depth approach are highly correlated with those generated by ddPCR for three representative DUF1220 clades. By simulation, we demonstrate that our method provides sufficient resolution to analyze DUF1220 copy number variation at three levels: (1) DUF1220 clade copy number within individual genes and groups of genes (gene-specific clade groups) (2) genome wide DUF1220 clade copies and (3) gene copy number for DUF1220-encoding genes. To our knowledge, this is the first method to accurately measure copies of all six DUF1220 clades and the first method to provide gene specific resolution of these clades. This allows one to discriminate among the ~300 haploid human DUF1220 copies to an extent not possible with any other method. The result is a greatly enhanced capability to analyze the

  3. High-Resolution Analysis of Gene Copy Number Alterations in Human Prostate Cancer Using CGH on cDNA Microarrays: Impact of Copy Number on Gene Expression

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    Maija Wolf

    2004-05-01

    Full Text Available Identification of target genes for genetic rearrangements in prostate cancer and the impact of copy number changes on gene expression are currently not well understood. Here, we applied high-resolution comparative genomic hybridization (CGH on cDNA microarrays for analysis of prostate cancer cell lines. CGH microarrays identified most of the alterations detected by classical chromosomal CGH, as well as a number of previously unreported alterations. Specific recurrent regions of gain (28 and loss (18 were found, their boundaries defined with sub-megabasepair accuracy. The most common changes included copy number decreases at 13% and gains at iq and 5p. Refined mapping identified several sites, such as at 13q (33-44, 49-51, 74-76 Mbp from the p-telomere, which matched with minimal regions of loss seen in extensive loss of heterozygosity mapping studies of large numbers of tumors. Previously unreported recurrent changes were found at 2p, 2q, 3p, 17q (losses, at 3q, 5p, 6p (gains. Integration of genomic and transcriptomic data revealed the role of individual candidate target genes for genomic alterations as well as a highly significant (P < .0001 overall association between copy number levels and the percentage of differentially expressed genes. Across the genome, the overall impact of copy number on gene expression levels was, to a large extent, attributable to low-level gains and losses of copy number, corresponding to common deletions and gains of often large chromosomal regions.

  4. Construction of thiostrepton-inducible, high-copy-number expression vectors for use in Streptomyces spp.

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    Takano, Eriko; White, Janet; Thompson, Charles J.; Bibb, Mervyn J.

    1995-01-01

    A high-copy-number plasmid expression vector (pIJ6021) was constructed that contains a thiostrepton-inducible promoter, PtipA, from Streptomyces lividans 66. The promoter and ribosome-binding site of tipA lie immediately upstream from a multiple cloning site (MCS) which begins with a NdeI site (5'-C

  5. Quadruplex MAPH: improvement of throughput in high-resolution copy number screening

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    Walker Susan

    2009-09-01

    Full Text Available Abstract Background Copy number variation (CNV in the human genome is recognised as a widespread and important source of human genetic variation. Now the challenge is to screen for these CNVs at high resolution in a reliable, accurate and cost-effective way. Results Multiplex Amplifiable Probe Hybridisation (MAPH is a sensitive, high-resolution technology appropriate for screening for CNVs in a defined region, for a targeted population. We have developed MAPH to a highly multiplexed format ("QuadMAPH" that allows the user a four-fold increase in the number of loci tested simultaneously. We have used this method to analyse a genomic region of 210 kb, including the MSH2 gene and 120 kb of flanking DNA. We show that the QuadMAPH probes report copy number with equivalent accuracy to simplex MAPH, reliably demonstrating diploid copy number in control samples and accurately detecting deletions in Hereditary Non-Polyposis Colorectal Cancer (HNPCC samples. Conclusion QuadMAPH is an accurate, high-resolution method that allows targeted screening of large numbers of subjects without the expense of genome-wide approaches. Whilst we have applied this technique to a region of the human genome, it is equally applicable to the genomes of other organisms.

  6. High copy number of mitochondrial DNA predicts poor prognosis in patients with advanced stage colon cancer.

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    Wang, Yun; He, Shuixiang; Zhu, Xingmei; Qiao, Wei; Zhang, Juan

    2016-12-23

    The aim of this investigation was to determine whether alterations in mitochondrial DNA (mtDNA) copy number in colon cancer were associated with clinicopathological parameters and postsurgical outcome. By quantitative real-time PCR assay, the mtDNA copy number was detected in a cohort of colon cancer and matched adjacent colon tissues (n = 162). The majority of patients had higher mtDNA content in colon cancer tissues than matched adjacent colon tissues. Moreover, high mtDNA content in tumor tissues was associated with larger tumor size, higher serum CEA level, advanced TNM stage, vascular emboli, and liver metastases. Further survival curve analysis showed that high mtDNA content was related to the worst survival in patients with colon cancer at advanced TNM stage. High mtDNA content is a potential effective factor of poor prognosis in patients with advanced stage colon cancer.

  7. Toward accurate high-throughput SNP genotyping in the presence of inherited copy number variation

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    Aldred Micheala A

    2007-07-01

    Full Text Available Abstract Background The recent discovery of widespread copy number variation in humans has forced a shift away from the assumption of two copies per locus per cell throughout the autosomal genome. In particular, a SNP site can no longer always be accurately assigned one of three genotypes in an individual. In the presence of copy number variability, the individual may theoretically harbor any number of copies of each of the two SNP alleles. Results To address this issue, we have developed a method to infer a "generalized genotype" from raw SNP microarray data. Here we apply our approach to data from 48 individuals and uncover thousands of aberrant SNPs, most in regions that were previously unreported as copy number variants. We show that our allele-specific copy numbers follow Mendelian inheritance patterns that would be obscured in the absence of SNP allele information. The interplay between duplication and point mutation in our data shed light on the relative frequencies of these events in human history, showing that at least some of the duplication events were recurrent. Conclusion This new multi-allelic view of SNPs has a complicated role in disease association studies, and further work will be necessary in order to accurately assess its importance. Software to perform generalized genotyping from SNP array data is freely available online 1.

  8. DNA copy number changes in high-grade malignant peripheral nerve sheath tumors by array CGH

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    Bjerkehagen Bodil

    2008-06-01

    Full Text Available Abstract Background Malignant peripheral nerve sheath tumors (MPNSTs are rare and highly aggressive soft tissue tumors showing complex chromosomal aberrations. In order to identify recurrent chromosomal regions of gain and loss, and thereby novel gene targets of potential importance for MPNST development and/or progression, we have analyzed DNA copy number changes in seven high-grade MPNSTs using microarray-based comparative genomic hybridization (array CGH. Results Considerable more gains than losses were observed, and the most frequent minimal recurrent regions of gain included 1q24.1-q24.2, 1q24.3-q25.1, 8p23.1-p12, 9q34.11-q34.13 and 17q23.2-q25.3, all gained in five of seven samples. The 17q23.2-q25.3 region was gained in all five patients with poor outcome and not in the two patients with disease-free survival. cDNA microarray analysis and quantitative real-time reverse transcription PCR were used to investigate expression of genes located within these regions. The gene lysyl oxidase-like 2 (LOXL2 was identified as a candidate target for the 8p23.1-p12 gain. Within 17q, the genes topoisomerase II-α (TOP2A, ets variant gene 4 (E1A enhancer binding protein, E1AF (ETV4 and baculoviral IAP repeat-containing 5 (survivin (BIRC5 showed increased expression in all samples compared to two benign tumors. Increased expression of these genes has previously been associated with poor survival in other malignancies, and for TOP2A, in MPNSTs as well. In addition, we have analyzed the expression of five micro RNAs located within the 17q23.2-q25.3 region, but none of them showed high expression levels compared to the benign tumors. Conclusion Our study shows the potential of using DNA copy number changes obtained by array CGH to predict the prognosis of MPNST patients. Although no clear correlations between the expression level and patient outcome were observed, the genes TOP2A, ETV4 and BIRC5 are interesting candidate targets for the 17q gain associated

  9. High Glucose-Induced Oxidative Stress Increases the Copy Number of Mitochondrial DNA in Human Mesangial Cells

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    Ghada Al-Kafaji

    2013-01-01

    Full Text Available Oxidative damage to mitochondrial DNA (mtDNA has been linked to the pathogenicity of diabetic nephropathy. We tested the hypothesis that mtDNA copy number may be increased in human mesangial cells in response to high glucose-induced reactive oxygen species (ROS to compensate for damaged mtDNA. The effect of manganese superoxide dismutase mimetic (MnTBAP on glucose-induced mtDNA copy number was also examined. The copy number of mtDNA was determined by real-time PCR in human mesangial cells cultured in 5 mM glucose, 25 mM glucose, and mannitol (osmotic control, as well as in cells cultured in 25 mM glucose in the presence and absence of 200 μM MnTBAP. Intracellular ROS was assessed by confocal microscopy and flow cytometry in human mesangial cells. The copy number of mtDNA was significantly increased when human mesangial cells were incubated with 25 mM glucose compared to 5 mM glucose and mannitol. In addition, 25 mM glucose rapidly generated ROS in the cells, which was not detected in 5 mM glucose. Furthermore, mtDNA copy number was significantly decreased and maintained to normal following treatment of cells with 25 mM glucose and MnTBAP compared to 25 mM glucose alone. Inclusion of MnTBAP during 25 mM glucose incubation inhibited mitochondrial superoxide in human mesangial cells. Increased mtDNA copy number in human mesangial cells by high glucose could contribute to increased mitochondrial superoxide, and prevention of mtDNA copy number could have potential in retarding the development of diabetic nephropathy.

  10. High quality copy number and genotype data from FFPE samples using Molecular Inversion Probe (MIP) microarrays

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    Wang, Yuker; Carlton, Victoria E.H.; Karlin-Neumann, George; Sapolsky, Ronald; Zhang, Li; Moorhead, Martin; Wang, Zhigang C.; Richardson, Andrea L.; Warren, Robert; Walther, Axel; Bondy, Melissa; Sahin, Aysegul; Krahe, Ralf; Tuna, Musaffe; Thompson, Patricia A.; Spellman, Paul T.; Gray, Joe W.; Mills, Gordon B.; Faham, Malek

    2009-02-24

    A major challenge facing DNA copy number (CN) studies of tumors is that most banked samples with extensive clinical follow-up information are Formalin-Fixed Paraffin Embedded (FFPE). DNA from FFPE samples generally underperforms or suffers high failure rates compared to fresh frozen samples because of DNA degradation and cross-linking during FFPE fixation and processing. As FFPE protocols may vary widely between labs and samples may be stored for decades at room temperature, an ideal FFPE CN technology should work on diverse sample sets. Molecular Inversion Probe (MIP) technology has been applied successfully to obtain high quality CN and genotype data from cell line and frozen tumor DNA. Since the MIP probes require only a small ({approx}40 bp) target binding site, we reasoned they may be well suited to assess degraded FFPE DNA. We assessed CN with a MIP panel of 50,000 markers in 93 FFPE tumor samples from 7 diverse collections. For 38 FFPE samples from three collections we were also able to asses CN in matched fresh frozen tumor tissue. Using an input of 37 ng genomic DNA, we generated high quality CN data with MIP technology in 88% of FFPE samples from seven diverse collections. When matched fresh frozen tissue was available, the performance of FFPE DNA was comparable to that of DNA obtained from matched frozen tumor (genotype concordance averaged 99.9%), with only a modest loss in performance in FFPE. MIP technology can be used to generate high quality CN and genotype data in FFPE as well as fresh frozen samples.

  11. Genome-wide copy number profiling using high-density SNP array in chickens.

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    Yi, G; Qu, L; Chen, S; Xu, G; Yang, N

    2015-04-01

    Phenotypic diversity is a direct consequence resulting mainly from the impact of underlying genetic variation, and recent studies have shown that copy number variation (CNV) is emerging as an important contributor to both phenotypic variability and disease susceptibility. Herein, we performed a genome-wide CNV scan in 96 chickens from 12 diversified breeds, benefiting from the high-density Affymetrix 600 K SNP arrays. We identified a total of 231 autosomal CNV regions (CNVRs) encompassing 5.41 Mb of the chicken genome and corresponding to 0.59% of the autosomal sequence. The length of these CNVRs ranged from 2.6 to 586.2 kb with an average of 23.4 kb, including 130 gain, 93 loss and eight both gain and loss events. These CNVRs, especially deletions, had lower GC content and were located particularly in gene deserts. In particular, 102 CNVRs harbored 128 chicken genes, most of which were enriched in immune responses. We obtained 221 autosomal CNVRs after converting probe coordinates to Galgal3, and comparative analysis with previous studies illustrated that 153 of these CNVRs were regarded as novel events. Furthermore, qPCR assays were designed for 11 novel CNVRs, and eight (72.73%) were validated successfully. In this study, we demonstrated that the high-density 600 K SNP array can capture CNVs with higher efficiency and accuracy and highlighted the necessity of integrating multiple technologies and algorithms. Our findings provide a pioneering exploration of chicken CNVs based on a high-density SNP array, which contributes to a more comprehensive understanding of genetic variation in the chicken genome and is beneficial to unearthing potential CNVs underlying important traits of chickens. © 2015 Stichting International Foundation for Animal Genetics.

  12. Copy number variation across European populations.

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    Wanting Chen

    Full Text Available Genome analysis provides a powerful approach to test for evidence of genetic variation within and between geographical regions and local populations. Copy number variants which comprise insertions, deletions and duplications of genomic sequence provide one such convenient and informative source. Here, we investigate copy number variants from genome wide scans of single nucleotide polymorphisms in three European population isolates, the island of Vis in Croatia, the islands of Orkney in Scotland and the South Tyrol in Italy. We show that whereas the overall copy number variant frequencies are similar between populations, their distribution is highly specific to the population of origin, a finding which is supported by evidence for increased kinship correlation for specific copy number variants within populations.

  13. Pseudosymmetry, high copy number and twinning complicate the structure determination of Desulfovibrio desulfuricans (ATCC 29577) flavodoxin.

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    Guelker, Megan; Stagg, Loren; Wittung-Stafshede, Pernilla; Shamoo, Yousif

    2009-06-01

    The crystal structure of oxidized flavodoxin from Desulfovibrio desulfuricans (ATCC 29577) was determined by molecular replacement in two crystal forms, P3(1)21 and P4(3), at 2.5 and 2.0 A resolution, respectively. Structure determination in space group P3(1)21 was challenging owing to the presence of pseudo-translational symmetry and a high copy number in the asymmetric unit (8). Initial phasing attempts in space group P3(1)21 by molecular replacement using a poor search model (46% identity) and multi-wavelength anomalous dispersion were unsuccessful. It was necessary to solve the structure in a second crystal form, space group P4(3), which was characterized by almost perfect twinning, in order to obtain a suitable search model for molecular replacement. This search model with complementary approaches to molecular replacement utilizing the pseudo-translational symmetry operators determined by analysis of the native Patterson map facilitated the selection and manual placement of molecules to generate an initial solution in the P3(1)21 crystal form. During the early stages of refinement, application of the appropriate twin law, (-h, -k, l), was required to converge to reasonable R-factor values despite the fact that in the final analysis the data were untwinned and the twin law could subsequently be removed. The approaches used in structure determination and refinement may be applicable to other crystal structures characterized by these complicating factors. The refined model shows flexibility of the flavin mononucleotide coordinating loops indicated by the isolation of two loop conformations and provides a starting point for the elucidation of the mechanism used for protein-partner recognition.

  14. High-throughput quantitative analysis with cell growth kinetic curves for low copy number mutant cells.

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    Xing, James Z; Gabos, Stephan; Huang, Biao; Pan, Tianhong; Huang, Min; Chen, Jie

    2012-10-01

    The mutation rate in cells induced by environmental genotoxic hazards is very low and difficult to detect using traditional cell counting assays. The established genetic toxicity tests currently recognized by regulatory authorities, such as conventional Ames and hypoxanthine guanine phosphoribosyl-transferase (HPRT) assays, are not well suited for higher-throughput screening as they require large amounts of test compounds and are very time consuming. In this study, we developed a novel cell-based assay for quantitative analysis of low numbers of cell copies with HPRT mutation induced by an environmental mutagen. The HPRT gene mutant cells induced by the mutagen were selected by 6-thioguanine (6-TG) and the cell's kinetic growth curve monitored by a real-time cell electronic sensor (RT-CES) system. When a threshold is set at a certain cell index (CI) level, samples with different initial mutant cell copies take different amounts of time in order for their growth (or CI accumulation) to cross this threshold. The more cells that are initially seeded in the test well, the faster the cell accumulation and therefore the shorter the time required to cross this threshold. Therefore, the culture time period required to cross the threshold of each sample corresponds to the original number of cells in the sample. A mutant cell growth time threshold (MT) value of each sample can be calculated to predict the number of original mutant cells. For mutagenesis determination, the RT-CES assay displayed an equal sensitivity (p > 0.05) and coefficients of variation values with good correlation to conventional HPRT mutagenic assays. Most importantly, the RT-CES mutation assay has a higher throughput than conventional cellular assays.

  15. Discovery of common Asian copy number variants using integrated high-resolution array CGH and massively parallel DNA sequencing.

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    Park, Hansoo; Kim, Jong-Il; Ju, Young Seok; Gokcumen, Omer; Mills, Ryan E; Kim, Sheehyun; Lee, Seungbok; Suh, Dongwhan; Hong, Dongwan; Kang, Hyunseok Peter; Yoo, Yun Joo; Shin, Jong-Yeon; Kim, Hyun-Jin; Yavartanoo, Maryam; Chang, Young Wha; Ha, Jung-Sook; Chong, Wilson; Hwang, Ga-Ram; Darvishi, Katayoon; Kim, Hyeran; Yang, Song Ju; Yang, Kap-Seok; Kim, Hyungtae; Hurles, Matthew E; Scherer, Stephen W; Carter, Nigel P; Tyler-Smith, Chris; Lee, Charles; Seo, Jeong-Sun

    2010-05-01

    Copy number variants (CNVs) account for the majority of human genomic diversity in terms of base coverage. Here, we have developed and applied a new method to combine high-resolution array comparative genomic hybridization (CGH) data with whole-genome DNA sequencing data to obtain a comprehensive catalog of common CNVs in Asian individuals. The genomes of 30 individuals from three Asian populations (Korean, Chinese and Japanese) were interrogated with an ultra-high-resolution array CGH platform containing 24 million probes. Whole-genome sequencing data from a reference genome (NA10851, with 28.3x coverage) and two Asian genomes (AK1, with 27.8x coverage and AK2, with 32.0x coverage) were used to transform the relative copy number information obtained from array CGH experiments into absolute copy number values. We discovered 5,177 CNVs, of which 3,547 were putative Asian-specific CNVs. These common CNVs in Asian populations will be a useful resource for subsequent genetic studies in these populations, and the new method of calling absolute CNVs will be essential for applying CNV data to personalized medicine.

  16. High frequency of rare copy number variants affecting functionally related genes in patients with structural brain malformations

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    Kariminejad, Roxana; Lind-Thomsen, Allan; Tümer, Zeynep;

    2011-01-01

    ) to investigate copy number variants (CNVs) in a cohort of 169 patients with various structural brain malformations including lissencephaly, polymicrogyria, focal cortical dysplasia, and corpus callosum agenesis. The majority of the patients had intellectual disabilities (ID) and suffered from symptomatic...

  17. Adaptive copy number evolution in malaria parasites.

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    Shalini Nair

    2008-10-01

    Full Text Available Copy number polymorphism (CNP is ubiquitous in eukaryotic genomes, but the degree to which this reflects the action of positive selection is poorly understood. The first gene in the Plasmodium folate biosynthesis pathway, GTP-cyclohydrolase I (gch1, shows extensive CNP. We provide compelling evidence that gch1 CNP is an adaptive consequence of selection by antifolate drugs, which target enzymes downstream in this pathway. (1 We compared gch1 CNP in parasites from Thailand (strong historical antifolate selection with those from neighboring Laos (weak antifolate selection. Two percent of chromosomes had amplified copy number in Laos, while 72% carried multiple (2-11 copies in Thailand, and differentiation exceeded that observed at 73 synonymous SNPs. (2 We found five amplicon types containing one to greater than six genes and spanning 1 to >11 kb, consistent with parallel evolution and strong selection for this gene amplification. gch1 was the only gene occurring in all amplicons suggesting that this locus is the target of selection. (3 We observed reduced microsatellite variation and increased linkage disequilibrium (LD in a 900-kb region flanking gch1 in parasites from Thailand, consistent with rapid recent spread of chromosomes carrying multiple copies of gch1. (4 We found that parasites bearing dhfr-164L, which causes high-level resistance to antifolate drugs, carry significantly (p = 0.00003 higher copy numbers of gch1 than parasites bearing 164I, indicating functional association between genes located on different chromosomes but linked in the same biochemical pathway. These results demonstrate that CNP at gch1 is adaptive and the associations with dhfr-164L strongly suggest a compensatory function. More generally, these data demonstrate how selection affects multiple enzymes in a single biochemical pathway, and suggest that investigation of structural variation may provide a fast-track to locating genes underlying adaptation.

  18. Measuring Absolute RNA Copy Numbers at High Temporal Resolution Reveals Transcriptome Kinetics in Development

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    Nick D.L. Owens

    2016-01-01

    Full Text Available Transcript regulation is essential for cell function, and misregulation can lead to disease. Despite technologies to survey the transcriptome, we lack a comprehensive understanding of transcript kinetics, which limits quantitative biology. This is an acute challenge in embryonic development, where rapid changes in gene expression dictate cell fate decisions. By ultra-high-frequency sampling of Xenopus embryos and absolute normalization of sequence reads, we present smooth gene expression trajectories in absolute transcript numbers. During a developmental period approximating the first 8 weeks of human gestation, transcript kinetics vary by eight orders of magnitude. Ordering genes by expression dynamics, we find that “temporal synexpression” predicts common gene function. Remarkably, a single parameter, the characteristic timescale, can classify transcript kinetics globally and distinguish genes regulating development from those involved in cellular metabolism. Overall, our analysis provides unprecedented insight into the reorganization of maternal and embryonic transcripts and redefines our ability to perform quantitative biology.

  19. Hacking DNA copy number for circuit engineering.

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    Wu, Feilun; You, Lingchong

    2017-07-27

    DNA copy number represents an essential parameter in the dynamics of synthetic gene circuits but typically is not explicitly considered. A new study demonstrates how dynamic control of DNA copy number can serve as an effective strategy to program robust oscillations in gene expression circuits.

  20. A Single-Array-Based Method for Detecting Copy Number Variants Using Affymetrix High Density SNP Arrays and its Application to Breast Cancer.

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    Li, Ming; Wen, Yalu; Fu, Wenjiang

    2014-01-01

    Cumulative evidence has shown that structural variations, due to insertions, deletions, and inversions of DNA, may contribute considerably to the development of complex human diseases, such as breast cancer. High-throughput genotyping technologies, such as Affymetrix high density single-nucleotide polymorphism (SNP) arrays, have produced large amounts of genetic data for genome-wide SNP genotype calling and copy number estimation. Meanwhile, there is a great need for accurate and efficient statistical methods to detect copy number variants. In this article, we introduce a hidden-Markov-model (HMM)-based method, referred to as the PICR-CNV, for copy number inference. The proposed method first estimates copy number abundance for each single SNP on a single array based on the raw fluorescence values, and then standardizes the estimated copy number abundance to achieve equal footing among multiple arrays. This method requires no between-array normalization, and thus, maintains data integrity and independence of samples among individual subjects. In addition to our efforts to apply new statistical technology to raw fluorescence values, the HMM has been applied to the standardized copy number abundance in order to reduce experimental noise. Through simulations, we show our refined method is able to infer copy number variants accurately. Application of the proposed method to a breast cancer dataset helps to identify genomic regions significantly associated with the disease.

  1. Characteristics of Highly Polymorphic Segmental Copy-Number Variations Observed in Japanese by BAC-Array-CGH

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    Takahashi, Norio; Satoh, Yasunari; Sasaki, Keiko; Shimoichi, Yuko; Sugita, Keiko; Katayama, Hiroaki

    2011-01-01

    Segmental copy-number variations (CNVs) may contribute to genetic variation in humans. Reports of the existence and characteristics of CNVs in a large Japanese cohort are quite limited. We report the data from a large Japanese population. We conducted population screening for 213 unrelated Japanese individuals using comparative genomic hybridization based on a bacterial artificial chromosome microarray (BAC-aCGH). We summarize the data by focusing on highly polymorphic CNVs in ≥5.0% of the individual, since they may be informative for demonstrating the relationships between genotypes and their phenotypes. We found a total of 680 CNVs at 16 different BAC-regions in the genome. The majority of the polymorphic CNVs presented on BAC-clones that overlapped with regions of segmental duplication, and the majority of the polymorphic CNVs observed in this population had been previously reported in other publications. Some of the CNVs contained genes which might be related to phenotypic heterogeneity among individuals. PMID:21197411

  2. A High-Throughput Computational Framework for Identifying Significant Copy Number Aberrations from Array Comparative Genomic Hybridisation Data

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    Ian Roberts

    2012-01-01

    Full Text Available Reliable identification of copy number aberrations (CNA from comparative genomic hybridization data would be improved by the availability of a generalised method for processing large datasets. To this end, we developed swatCGH, a data analysis framework and region detection heuristic for computational grids. swatCGH analyses sequentially displaced (sliding windows of neighbouring probes and applies adaptive thresholds of varying stringency to identify the 10% of each chromosome that contains the most frequently occurring CNAs. We used the method to analyse a published dataset, comparing data preprocessed using four different DNA segmentation algorithms, and two methods for prioritising the detected CNAs. The consolidated list of the most commonly detected aberrations confirmed the value of swatCGH as a simplified high-throughput method for identifying biologically significant CNA regions of interest.

  3. A High-Throughput Computational Framework for Identifying Significant Copy Number Aberrations from Array Comparative Genomic Hybridisation Data

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    Roberts, Ian; Carter, Stephanie A.; Scarpini, Cinzia G.; Karagavriilidou, Konstantina; Barna, Jenny C. J.; Calleja, Mark; Coleman, Nicholas

    2012-01-01

    Reliable identification of copy number aberrations (CNA) from comparative genomic hybridization data would be improved by the availability of a generalised method for processing large datasets. To this end, we developed swatCGH, a data analysis framework and region detection heuristic for computational grids. swatCGH analyses sequentially displaced (sliding) windows of neighbouring probes and applies adaptive thresholds of varying stringency to identify the 10% of each chromosome that contains the most frequently occurring CNAs. We used the method to analyse a published dataset, comparing data preprocessed using four different DNA segmentation algorithms, and two methods for prioritising the detected CNAs. The consolidated list of the most commonly detected aberrations confirmed the value of swatCGH as a simplified high-throughput method for identifying biologically significant CNA regions of interest. PMID:23008709

  4. High-throughput sequencing and copy number variation detection using formalin fixed embedded tissue in metastatic gastric cancer.

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    Seokhwi Kim

    Full Text Available In the era of targeted therapy, mutation profiling of cancer is a crucial aspect of making therapeutic decisions. To characterize cancer at a molecular level, the use of formalin-fixed paraffin-embedded tissue is important. We tested the Ion AmpliSeq Cancer Hotspot Panel v2 and nCounter Copy Number Variation Assay in 89 formalin-fixed paraffin-embedded gastric cancer samples to determine whether they are applicable in archival clinical samples for personalized targeted therapies. We validated the results with Sanger sequencing, real-time quantitative PCR, fluorescence in situ hybridization and immunohistochemistry. Frequently detected somatic mutations included TP53 (28.17%, APC (10.1%, PIK3CA (5.6%, KRAS (4.5%, SMO (3.4%, STK11 (3.4%, CDKN2A (3.4% and SMAD4 (3.4%. Amplifications of HER2, CCNE1, MYC, KRAS and EGFR genes were observed in 8 (8.9%, 4 (4.5%, 2 (2.2%, 1 (1.1% and 1 (1.1% cases, respectively. In the cases with amplification, fluorescence in situ hybridization for HER2 verified gene amplification and immunohistochemistry for HER2, EGFR and CCNE1 verified the overexpression of proteins in tumor cells. In conclusion, we successfully performed semiconductor-based sequencing and nCounter copy number variation analyses in formalin-fixed paraffin-embedded gastric cancer samples. High-throughput screening in archival clinical samples enables faster, more accurate and cost-effective detection of hotspot mutations or amplification in genes.

  5. High burden of copy number alterations and c-MYC amplification in prostate cancer from BRCA2 germline mutation carriers

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    Castro, E.; Jugurnauth-Little, S.; Karlsson, Q.; Al-Shahrour, F.; Pineiro-Yanez, E.; Van de Poll, F.; Leongamornlert, D.; Dadaev, T.; Govindasami, K.; Guy, M.; Eeles, R.; Kote-Jarai, Z.; Oosterwijk, J. C.

    2015-01-01

    Background: Germline BRCA2 mutations are associated with poorer outcome prostate cancer ( PCa) compared with sporadic tumours but this association remains to be characterised. In this study, we aim to assess if there is a signature set of copy number alterations ( CNA) that could aid to the identifi

  6. Genome-wide mapping of copy number variation in humans: comparative analysis of high resolution array platforms.

    Directory of Open Access Journals (Sweden)

    Rajini R Haraksingh

    Full Text Available Accurate and efficient genome-wide detection of copy number variants (CNVs is essential for understanding human genomic variation, genome-wide CNV association type studies, cytogenetics research and diagnostics, and independent validation of CNVs identified from sequencing based technologies. Numerous, array-based platforms for CNV detection exist utilizing array Comparative Genome Hybridization (aCGH, Single Nucleotide Polymorphism (SNP genotyping or both. We have quantitatively assessed the abilities of twelve leading genome-wide CNV detection platforms to accurately detect Gold Standard sets of CNVs in the genome of HapMap CEU sample NA12878, and found significant differences in performance. The technologies analyzed were the NimbleGen 4.2 M, 2.1 M and 3×720 K Whole Genome and CNV focused arrays, the Agilent 1×1 M CGH and High Resolution and 2×400 K CNV and SNP+CGH arrays, the Illumina Human Omni1Quad array and the Affymetrix SNP 6.0 array. The Gold Standards used were a 1000 Genomes Project sequencing-based set of 3997 validated CNVs and an ultra high-resolution aCGH-based set of 756 validated CNVs. We found that sensitivity, total number, size range and breakpoint resolution of CNV calls were highest for CNV focused arrays. Our results are important for cost effective CNV detection and validation for both basic and clinical applications.

  7. Unbiased K-mer Analysis Reveals Changes in Copy Number of Highly Repetitive Sequences During Maize Domestication and Improvement

    Science.gov (United States)

    Liu, Sanzhen; Zheng, Jun; Migeon, Pierre; Ren, Jie; Hu, Ying; He, Cheng; Liu, Hongjun; Fu, Junjie; White, Frank F.; Toomajian, Christopher; Wang, Guoying

    2017-01-01

    The major component of complex genomes is repetitive elements, which remain recalcitrant to characterization. Using maize as a model system, we analyzed whole genome shotgun (WGS) sequences for the two maize inbred lines B73 and Mo17 using k-mer analysis to quantify the differences between the two genomes. Significant differences were identified in highly repetitive sequences, including centromere, 45S ribosomal DNA (rDNA), knob, and telomere repeats. Genotype specific 45S rDNA sequences were discovered. The B73 and Mo17 polymorphic k-mers were used to examine allele-specific expression of 45S rDNA in the hybrids. Although Mo17 contains higher copy number than B73, equivalent levels of overall 45S rDNA expression indicates that transcriptional or post-transcriptional regulation mechanisms operate for the 45S rDNA in the hybrids. Using WGS sequences of B73xMo17 doubled haploids, genomic locations showing differential repetitive contents were genetically mapped, which displayed different organization of highly repetitive sequences in the two genomes. In an analysis of WGS sequences of HapMap2 lines, including maize wild progenitor, landraces, and improved lines, decreases and increases in abundance of additional sets of k-mers associated with centromere, 45S rDNA, knob, and retrotransposons were found among groups, revealing global evolutionary trends of genomic repeats during maize domestication and improvement. PMID:28186206

  8. High-throughput single-cell analysis of low copy number β-galactosidase by a laboratory-built high-sensitivity flow cytometer.

    Science.gov (United States)

    Yang, Lingling; Huang, Tianxun; Zhu, Shaobin; Zhou, Yingxing; Jiang, Yunbin; Wang, Shuo; Chen, Yuqing; Wu, Lina; Yan, Xiaomei

    2013-10-15

    Single-cell analysis is vital in providing insights into the heterogeneity in molecular content and phenotypic characteristics of complex or clonal cell populations. As many essential proteins and most transcription factors are produced at a low copy number, analytical tools with superior sensitivity to enable the analysis of low abundance proteins in single cells are in high demand. β-galactosidase (β-gal) has been the standard cellular reporter for gene expression in both prokaryotic and eukaryotic cells. Here we report the development of a high-throughput method for the single-cell analysis of low copy number β-gal proteins using a laboratory-built high-sensitivity flow cytometer (HSFCM). Upon fluorescence staining with a fluorogenic substrate, quantitative measurements of the basal and near-basal expression of β-gal in single Escherichia coli BL21(DE3) cells were demonstrated. Statistical distribution can be determined quickly by analyzing thousands of individual cells in 1-2min, which reveals the heterogeneous expression pattern that is otherwise masked by the ensemble analysis. Combined with the quantitative fluorometric assay and the rapid bacterial enumeration by HSFCM, the β-gal expression distribution profile could be converted from arbitrary fluorescence units to protein copy numbers per cell. The sensitivity and speed of the HSFCM offers great capability in quantitative analysis of low abundance proteins in single cells, which would help gaining a deeper insight into the heterogeneity and fundamental biological processes in microbial populations.

  9. Enhancing genome-wide copy number variation identification by high density array CGH using diverse resources of pig breeds.

    Directory of Open Access Journals (Sweden)

    Jiying Wang

    Full Text Available Copy number variations (CNVs are important forms of genomic variation, and have attracted extensive attentions in humans as well as domestic animals. In the study, using a custom-designed 2.1 M array comparative genomic hybridization (aCGH, genome-wide CNVs were identified among 12 individuals from diverse pig breeds, including one Asian wild population, six Chinese indigenous breeds and two modern commercial breeds (Yorkshire and Landrace, with one individual of the other modern commercial breed, Duroc, as the reference. A total of 1,344 CNV regions (CNVRs were identified, covering 47.79 Mb (∼1.70% of the pig genome. The length of these CNVRs ranged from 3.37 Kb to 1,319.0 Kb with a mean of 35.56 Kb and a median of 11.11 Kb. Compared with similar studies reported, most of the CNVRs (74.18% were firstly identified in present study. In order to confirm these CNVRs, 21 CNVRs were randomly chosen to be validated by quantitative real time PCR (qPCR and a high rate (85.71% of confirmation was obtained. Functional annotation of CNVRs suggested that the identified CNVRs have important function, and may play an important role in phenotypic and production traits difference among various breeds. Our results are essential complementary to the CNV map in the pig genome, which will provide abundant genetic markers to investigate association studies between various phenotypes and CNVs in pigs.

  10. An all-statistics, high-speed algorithm for the analysis of copy number variation in genomes.

    Science.gov (United States)

    Chen, Chih-Hao; Lee, Hsing-Chung; Ling, Qingdong; Chen, Hsiao-Rong; Ko, Yi-An; Tsou, Tsong-Shan; Wang, Sun-Chong; Wu, Li-Ching; Lee, H C

    2011-07-01

    Detection of copy number variation (CNV) in DNA has recently become an important method for understanding the pathogenesis of cancer. While existing algorithms for extracting CNV from microarray data have worked reasonably well, the trend towards ever larger sample sizes and higher resolution microarrays has vastly increased the challenges they face. Here, we present Segmentation analysis of DNA (SAD), a clustering algorithm constructed with a strategy in which all operational decisions are based on simple and rigorous applications of statistical principles, measurement theory and precise mathematical relations. Compared with existing packages, SAD is simpler in formulation, more user friendly, much faster and less thirsty for memory, offers higher accuracy and supplies quantitative statistics for its predictions. Unique among such algorithms, SAD's running time scales linearly with array size; on a typical modern notebook, it completes high-quality CNV analyses for a 250 thousand-probe array in ∼1 s and a 1.8 million-probe array in ∼8 s.

  11. Characteristics of Highly Polymorphic Segmental Copy-Number Variations Observed in Japanese by BAC-Array-CGH

    Directory of Open Access Journals (Sweden)

    Norio Takahashi

    2011-01-01

    Full Text Available Segmental copy-number variations (CNVs may contribute to genetic variation in humans. Reports of the existence and characteristics of CNVs in a large Japanese cohort are quite limited. We report the data from a large Japanese population. We conducted population screening for 213 unrelated Japanese individuals using comparative genomic hybridization based on a bacterial artificial chromosome microarray (BAC-aCGH. We summarize the data by focusing on highly polymorphic CNVs in ≥5.0% of the individual, since they may be informative for demonstrating the relationships between genotypes and their phenotypes. We found a total of 680 CNVs at 16 different BAC-regions in the genome. The majority of the polymorphic CNVs presented on BAC-clones that overlapped with regions of segmental duplication, and the majority of the polymorphic CNVs observed in this population had been previously reported in other publications. Some of the CNVs contained genes which might be related to phenotypic heterogeneity among individuals.

  12. New multi-purpose high copy number vector with greater mitotic stability for diverse applications in fission yeast Schizosaccharomyces pombe.

    Science.gov (United States)

    Verma, Hemant Kumar; Singh, Jagmohan

    2012-11-01

    We have constructed a pUC19-based multipurpose ATG vector in Schizosaccharomyces pombe with higher copy number and mitotic stability possible with commonly used vectors. The vector, having an NdeI site in its polylinker to provide ATG site for expression, carries a greatly truncated version of URA3 gene, URA3m, of Saccharomyces cerevisiae as a selection marker. In addition, it contains the mat2P-right flank region (mat2P-RF) of S. pombe as an autonomous replicating sequence (ARS) and a polylinker with wider choice of restriction sites. While URA3m confers an increase in plasmid copy number up to 200 copies/cell, mat2P-RF imparts greater mitotic stability than the standard ars1 element of S. pombe. Finally, the vector also includes the transcription termination signal of the nmt1 gene (Tnmt1). This basic vector should serve as a versatile tool for studies of gene function in S. pombe.

  13. Genome-wide copy number analysis using copy number inferring tool (CNIT) and DNA pooling.

    Science.gov (United States)

    Lin, Chien-hsing; Huang, Mei-chu; Li, Ling-hui; Wu, Jer-yuarn; Chen, Yuan-tsong; Fann, Cathy S J

    2008-08-01

    Copy number variation (CNV) has become an important genomic structure element in the human population, and some CNVs are related to specific traits and diseases. Moreover, analysis of human genomes has been potentiated by the use of high-resolution microarrays that assess single nucleotide polymorphisms (SNPs). Although many programs have been designed to analyze data from Affymetrix SNP microarrays, they all have high false-positive rates (FPRs) in copy number (CN) analyses. Copy number analysis tool (CNAT) 4.0 is a recently developed program that offers improved CN estimation, but small amplifications and deletions are lost when using the smoothing procedure. Here, we propose a copy number inferring tool (CNIT) algorithm for the 100K SNP microarray to investigate CNVs at 29.6-kb resolution. CNIT estimated SNP allelic and total CN with reliable P values based on intensity data. In addition, the hidden Markov model (HMM) method was applied to predict regions having altered CN by considering contiguous SNPs. Based on a CN analysis of 23 unrelated Taiwanese and 30 HapMap Centre d'Etude du Polymorphisme Humain (CEPH) trios, CNIT showed higher accuracy and power than other programs. The FPRs and false-negative rates (FNRs) of CNIT were 0.1% and 0.16%, respectively. CNIT also showed better sensitivity for detecting small amplifications and deletions. Furthermore, DNA pooling of 10 and 30 normal unrelated individuals were applied to the 100K SNP microarray, respectively, and 12 common CN-variable regions were identified, suggesting that DNA pooling can be applied to discover common CNVs.

  14. The CNVrd2 package: measurement of copy number at complex loci using high-throughput sequencing data.

    Science.gov (United States)

    Nguyen, Hoang T; Merriman, Tony R; Black, Michael A

    2014-01-01

    Recent advances in high-throughout sequencing technologies have made it possible to accurately assign copy number (CN) at CN variable loci. However, current analytic methods often perform poorly in regions in which complex CN variation is observed. Here we report the development of a read depth-based approach, CNVrd2, for investigation of CN variation using high-throughput sequencing data. This methodology was developed using data from the 1000 Genomes Project from the CCL3L1 locus, and tested using data from the DEFB103A locus. In both cases, samples were selected for which paralog ratio test data were also available for comparison. The CNVrd2 method first uses observed read-count ratios to refine segmentation results in one population. Then a linear regression model is applied to adjust the results across multiple populations, in combination with a Bayesian normal mixture model to cluster segmentation scores into groups for individual CN counts. The performance of CNVrd2 was compared to that of two other read depth-based methods (CNVnator, cn.mops) at the CCL3L1 and DEFB103A loci. The highest concordance with the paralog ratio test method was observed for CNVrd2 (77.8/90.4% for CNVrd2, 36.7/4.8% for cn.mops and 7.2/1% for CNVnator at CCL3L1 and DEF103A). CNVrd2 is available as an R package as part of the Bioconductor project: http://www.bioconductor.org/packages/release/bioc/html/CNVrd2.html.

  15. The CNVrd2 package: measurement of copy number at complex loci using high-throughput sequencing data

    Directory of Open Access Journals (Sweden)

    Hoang eNguyen

    2014-08-01

    Full Text Available Recent advances in high-throughout sequencing technologies have made it possible to accurately assign copy number (CN at CN variable loci. However, current analytic methods often perform poorly in regions in which complex CN variation is observed. Here we report the development of a read depth-based approach, CNVrd2, for investigation of CN variation using high-throughput sequencing data. This methodology was developed using data from the 1000 Genomes Project from the CCL3L1 locus, and tested using data from the DEFB103A locus. In both cases, samples were selected for which paralogue ratio test data were also available for comparison. The CNVrd2 method first uses observed read-count ratios to refine segmentation results in one population. Then a linear regression model is applied to adjust the results across multiple populations, in combination with a Bayesian normal mixture model to cluster segmentation scores into groups for individual CN counts. The performance of CNVrd2 was compared to that of two other read depth-based methods (CNVnator, cn.mops at the CCL3L1 and DEFB103A loci, and the highest concordance with the paralog ratio test method was observed for CNVrd2 (77.8%/90.4% for CNVrd2, 36.7%/4.8% for cn.mops and 7.2%/1% for CNVnator at CCL3L1 and DEF103A. CNVrd2 is available as an R package as part of the Bioconductor project: http://www.bioconductor.org/packages/release/bioc/html/CNVrd2.html.

  16. Screening for copy-number alterations and loss of heterozygosity in chronic lymphocytic leukemia--a comparative study of four differently designed, high resolution microarray platforms

    DEFF Research Database (Denmark)

    2008-01-01

    Screening for gene copy-number alterations (CNAs) has improved by applying genome-wide microarrays, where SNP arrays also allow analysis of loss of heterozygozity (LOH). We here analyzed 10 chronic lymphocytic leukemia (CLL) samples using four different high-resolution platforms: BAC arrays (32K...... of 32 additional regions present in 2-3 platforms illustrated a discrepancy in detection of small CNAs, which often involved reported copy-number variations. LOH analysis using dChip revealed concordance of mainly large regions, but showed numerous, small nonoverlapping regions and LOH escaping...

  17. A Series of Medium and High Copy Number Arabinose-Inducible Escherichia coli Expression Vectors Compatible with pBR322 and pACYC184

    OpenAIRE

    Chakravartty, Vandana; Cronan, John E.

    2015-01-01

    The original pBAD24 plasmid and the derived lower copy number (the pBAD322 series) expression vectors have been widely used in Escherichia coli, Salmonella enterica, and related bacteria. However, a flexible pBAD expression system has been available only in pMB1 (ColE1) vectors. We report a series of pBAD vectors that replicate using the origin of plasmid RSF1030 that are compatible with pMB1 (ColE1) and p15A (pACYC) vectors. Both high (≥pBAD24) and medium (~pBAD322) copy number plasmids enco...

  18. Screening for copy-number alterations and loss of heterozygosity in chronic lymphocytic leukemia--a comparative study of four differently designed, high resolution microarray platforms

    DEFF Research Database (Denmark)

    Gunnarsson, R.; Staaf, J.; Jansson, M.;

    2008-01-01

    Screening for gene copy-number alterations (CNAs) has improved by applying genome-wide microarrays, where SNP arrays also allow analysis of loss of heterozygozity (LOH). We here analyzed 10 chronic lymphocytic leukemia (CLL) samples using four different high-resolution platforms: BAC arrays (32K...... detection. Evaluation of baseline variation and copy-number ratio response showed the best performance for the Agilent platform and confirmed the robustness of BAC arrays. Accordingly, these platforms demonstrated a higher degree of platform-specific CNAs. The SNP arrays displayed higher technical variation...

  19. Genome-wide copy number profiling on high-density bacterial artificial chromosomes, single-nucleotide polymorphisms, and oligonucleotide microarrays: a platform comparison based on statistical power analysis.

    NARCIS (Netherlands)

    Hehir-Kwa, J.Y.; Egmont-Peterson, M.; Janssen, I.M.; Smeets, D.F.C.M.; Geurts van Kessel, A.H.M.; Veltman, J.A.

    2007-01-01

    Recently, comparative genomic hybridization onto bacterial artificial chromosome (BAC) arrays (array-based comparative genomic hybridization) has proved to be successful for the detection of submicroscopic DNA copy-number variations in health and disease. Technological improvements to achieve a high

  20. Human copy number variation and complex genetic disease.

    Science.gov (United States)

    Girirajan, Santhosh; Campbell, Catarina D; Eichler, Evan E

    2011-01-01

    Copy number variants (CNVs) play an important role in human disease and population diversity. Advancements in technology have allowed for the analysis of CNVs in thousands of individuals with disease in addition to thousands of controls. These studies have identified rare CNVs associated with neuropsychiatric diseases such as autism, schizophrenia, and intellectual disability. In addition, copy number polymorphisms (CNPs) are present at higher frequencies in the population, show high diversity in copy number, sequence, and structure, and have been associated with multiple phenotypes, primarily related to immune or environmental response. However, the landscape of copy number variation still remains largely unexplored, especially for smaller CNVs and those embedded within complex regions of the human genome. An integrated approach including characterization of single nucleotide variants and CNVs in a large number of individuals with disease and normal genomes holds the promise of thoroughly elucidating the genetic basis of human disease and diversity.

  1. Number matters: control of mammalian mitochondrial DNA copy number.

    Science.gov (United States)

    Clay Montier, Laura L; Deng, Janice J; Bai, Yidong

    2009-03-01

    Regulation of mitochondrial biogenesis is essential for proper cellular functioning. Mitochondrial DNA (mtDNA) depletion and the resulting mitochondrial malfunction have been implicated in cancer, neurodegeneration, diabetes, aging, and many other human diseases. Although it is known that the dynamics of the mammalian mitochondrial genome are not linked with that of the nuclear genome, very little is known about the mechanism of mtDNA propagation. Nevertheless, our understanding of the mode of mtDNA replication has advanced in recent years, though not without some controversies. This review summarizes our current knowledge of mtDNA copy number control in mammalian cells, while focusing on both mtDNA replication and turnover. Although mtDNA copy number is seemingly in excess, we reason that mtDNA copy number control is an important aspect of mitochondrial genetics and biogenesis and is essential for normal cellular function.

  2. Global repeat discovery and estimation of genomic copy number in a large, complex genome using a high-throughput 454 sequence survey

    Directory of Open Access Journals (Sweden)

    Varala Kranthi

    2007-05-01

    Full Text Available Abstract Background Extensive computational and database tools are available to mine genomic and genetic databases for model organisms, but little genomic data is available for many species of ecological or agricultural significance, especially those with large genomes. Genome surveys using conventional sequencing techniques are powerful, particularly for detecting sequences present in many copies per genome. However these methods are time-consuming and have potential drawbacks. High throughput 454 sequencing provides an alternative method by which much information can be gained quickly and cheaply from high-coverage surveys of genomic DNA. Results We sequenced 78 million base-pairs of randomly sheared soybean DNA which passed our quality criteria. Computational analysis of the survey sequences provided global information on the abundant repetitive sequences in soybean. The sequence was used to determine the copy number across regions of large genomic clones or contigs and discover higher-order structures within satellite repeats. We have created an annotated, online database of sequences present in multiple copies in the soybean genome. The low bias of pyrosequencing against repeat sequences is demonstrated by the overall composition of the survey data, which matches well with past estimates of repetitive DNA content obtained by DNA re-association kinetics (Cot analysis. Conclusion This approach provides a potential aid to conventional or shotgun genome assembly, by allowing rapid assessment of copy number in any clone or clone-end sequence. In addition, we show that partial sequencing can provide access to partial protein-coding sequences.

  3. BAC TG-EMBED: one-step method for high-level, copy-number-dependent, position-independent transgene expression.

    Science.gov (United States)

    Bian, Qian; Belmont, Andrew S

    2010-06-01

    Chromosome position effects combined with transgene silencing of multi-copy plasmid insertions lead to highly variable and usually quite low expression levels of mini-genes integrated into mammalian chromosomes. Together, these effects greatly complicate obtaining high-level expression of therapeutic proteins in mammalian cells or reproducible expression of individual or multiple transgenes. Here, we report a simple, one-step procedure for obtaining high-level, reproducible mini-gene expression in mammalian cells. By inserting mini-genes at different locations within a BAC containing the DHFR housekeeping gene locus, we obtain copy-number-dependent, position-independent expression with chromosomal insertions of one to several hundred BAC copies. These multi-copy DHFR BAC insertions adopt similar large-scale chromatin conformations independent of their chromosome integration site, including insertions within centromeric heterochromatin. Prevention of chromosome position effects, therefore, may be the result of embedding the mini-gene within the BAC-specific large-scale chromatin structure. The expression of reporter mini-genes can be stably maintained during continuous, long-term culture in the presence of drug selection. Finally, we show that this method is extendable to reproducible, high-level expression of multiple mini-genes, providing improved expression of both single and multiple transgenes.

  4. Getting DNA copy numbers without control samples

    Directory of Open Access Journals (Sweden)

    Ortiz-Estevez Maria

    2012-08-01

    Full Text Available Abstract Background The selection of the reference to scale the data in a copy number analysis has paramount importance to achieve accurate estimates. Usually this reference is generated using control samples included in the study. However, these control samples are not always available and in these cases, an artificial reference must be created. A proper generation of this signal is crucial in terms of both noise and bias. We propose NSA (Normality Search Algorithm, a scaling method that works with and without control samples. It is based on the assumption that genomic regions enriched in SNPs with identical copy numbers in both alleles are likely to be normal. These normal regions are predicted for each sample individually and used to calculate the final reference signal. NSA can be applied to any CN data regardless the microarray technology and preprocessing method. It also finds an optimal weighting of the samples minimizing possible batch effects. Results Five human datasets (a subset of HapMap samples, Glioblastoma Multiforme (GBM, Ovarian, Prostate and Lung Cancer experiments have been analyzed. It is shown that using only tumoral samples, NSA is able to remove the bias in the copy number estimation, to reduce the noise and therefore, to increase the ability to detect copy number aberrations (CNAs. These improvements allow NSA to also detect recurrent aberrations more accurately than other state of the art methods. Conclusions NSA provides a robust and accurate reference for scaling probe signals data to CN values without the need of control samples. It minimizes the problems of bias, noise and batch effects in the estimation of CNs. Therefore, NSA scaling approach helps to better detect recurrent CNAs than current methods. The automatic selection of references makes it useful to perform bulk analysis of many GEO or ArrayExpress experiments without the need of developing a parser to find the normal samples or possible batches within the

  5. Identification of copy number variants in horses

    KAUST Repository

    Doan, R.

    2012-03-01

    Copy number variants (CNVs) represent a substantial source of genetic variation in mammals. However, the occurrence of CNVs in horses and their subsequent impact on phenotypic variation is unknown. We performed a study to identify CNVs in 16 horses representing 15 distinct breeds (Equus caballus) and an individual gray donkey (Equus asinus) using a whole-exome tiling array and the array comparative genomic hybridization methodology. We identified 2368 CNVs ranging in size from 197 bp to 3.5 Mb. Merging identical CNVs from each animal yielded 775 CNV regions (CNVRs), involving 1707 protein- and RNA-coding genes. The number of CNVs per animal ranged from 55 to 347, with median and mean sizes of CNVs of 5.3 kb and 99.4 kb, respectively. Approximately 6% of the genes investigated were affected by a CNV. Biological process enrichment analysis indicated CNVs primarily affected genes involved in sensory perception, signal transduction, and metabolism. CNVs also were identified in genes regulating blood group antigens, coat color, fecundity, lactation, keratin formation, neuronal homeostasis, and height in other species. Collectively, these data are the first report of copy number variation in horses and suggest that CNVs are common in the horse genome and may modulate biological processes underlying different traits observed among horses and horse breeds.

  6. High fidelity copy number analysis of formalin-fixed and paraffin-embedded tissues using Affymetrix Cytoscan HD chip.

    Directory of Open Access Journals (Sweden)

    Yan P Yu

    Full Text Available Detection of human genome copy number variation (CNV is one of the most important analyses in diagnosing human malignancies. Genome CNV detection in formalin-fixed and paraffin-embedded (FFPE tissues remains challenging due to suboptimal DNA quality and failure to use appropriate baseline controls for such tissues. Here, we report a modified method in analyzing CNV in FFPE tissues using microarray with Affymetrix Cytoscan HD chips. Gel purification was applied to select DNA with good quality and data of fresh frozen and FFPE tissues from healthy individuals were included as baseline controls in our data analysis. Our analysis showed a 91% overlap between CNV detection by microarray with FFPE tissues and chromosomal abnormality detection by karyotyping with fresh tissues on 8 cases of lymphoma samples. The CNV overlap between matched frozen and FFPE tissues reached 93.8%. When the analyses were restricted to regions containing genes, 87.1% concordance between FFPE and fresh frozen tissues was found. The analysis was further validated by Fluorescence In Situ Hybridization on these samples using probes specific for BRAF and CITED2. The results suggested that the modified method using Affymetrix Cytoscan HD chip gave rise to a significant improvement over most of the previous methods in terms of accuracy in detecting CNV in FFPE tissues. This FFPE microarray methodology may hold promise for broad application of CNV analysis on clinical samples.

  7. High-Throughput Amplicon-Based Copy Number Detection of 11 Genes in Formalin-Fixed Paraffin-Embedded Ovarian Tumour Samples by MLPA-Seq.

    Science.gov (United States)

    Kondrashova, Olga; Love, Clare J; Lunke, Sebastian; Hsu, Arthur L; Waring, Paul M; Taylor, Graham R

    2015-01-01

    Whilst next generation sequencing can report point mutations in fixed tissue tumour samples reliably, the accurate determination of copy number is more challenging. The conventional Multiplex Ligation-dependent Probe Amplification (MLPA) assay is an effective tool for measurement of gene dosage, but is restricted to around 50 targets due to size resolution of the MLPA probes. By switching from a size-resolved format, to a sequence-resolved format we developed a scalable, high-throughput, quantitative assay. MLPA-seq is capable of detecting deletions, duplications, and amplifications in as little as 5ng of genomic DNA, including from formalin-fixed paraffin-embedded (FFPE) tumour samples. We show that this method can detect BRCA1, BRCA2, ERBB2 and CCNE1 copy number changes in DNA extracted from snap-frozen and FFPE tumour tissue, with 100% sensitivity and >99.5% specificity.

  8. Copy number variation in the bovine genome

    DEFF Research Database (Denmark)

    Fadista, João; Thomsen, Bo; Holm, Lars-Erik;

    2010-01-01

    to genetic variation in cattle. Results We designed and used a set of NimbleGen CGH arrays that tile across the assayable portion of the cattle genome with approximately 6.3 million probes, at a median probe spacing of 301 bp. This study reports the highest resolution map of copy number variation...... in the cattle genome, with 304 CNV regions (CNVRs) being identified among the genomes of 20 bovine samples from 4 dairy and beef breeds. The CNVRs identified covered 0.68% (22 Mb) of the genome, and ranged in size from 1.7 to 2,031 kb (median size 16.7 kb). About 20% of the CNVs co-localized with segmental...

  9. Candidate gene copy number analysis by PCR and multicapillary electrophoresis.

    Science.gov (United States)

    Szantai, Eszter; Elek, Zsuzsanna; Guttman, András; Sasvari-Szekely, Maria

    2009-04-01

    Genetic polymorphisms are often considered as risk factors of complex diseases serving as valuable and easily detectable biomarkers, also stable during the whole lifespan. A novel type of genetic polymorphism has been identified just recently, referred to as gene copy number variation (CNV) or copy number polymorphism. CNV of glycogen synthase kinase 3 beta and its adjacent gene, Nr1i2 (pregnane X receptor isoform), has been reported to associate with bipolar depression. In our study we introduced multicapillary electrophoresis for gene copy number analysis as an affordable alternative to real-time PCR quantification with TaqMan gene probes. Our results show the reliability of the developed method based on conventional PCR followed by separation of products by multicapillary electrophoresis with quantitative evaluation. This method can be readily implemented for the analysis of candidate gene CNVs in high throughput clinical laboratories and also in personalized medicine care of depression-related risk factors.

  10. Rare copy number alterations and copy-neutral loss of heterozygosity revealed in ameloblastomas by high-density whole-genome microarray analysis

    DEFF Research Database (Denmark)

    Diniz, Marina Gonçalves; Duarte, Alessandra Pires; Villacis, Rolando A

    2017-01-01

    BACKGROUND: Ameloblastoma (unicystic, UA, or multicystic, MA) is a rare tumor associated with bone destruction and facial deformity. Its malignant counterpart is the ameloblastic carcinoma (AC). The BRAFV600E mutation is highly prevalent in all these tumors subtypes and cannot account for their d......BACKGROUND: Ameloblastoma (unicystic, UA, or multicystic, MA) is a rare tumor associated with bone destruction and facial deformity. Its malignant counterpart is the ameloblastic carcinoma (AC). The BRAFV600E mutation is highly prevalent in all these tumors subtypes and cannot account......, and PPP2R5A) covered by rare alterations, also including three MA and four normal oral tissues. RESULTS: Fifty-seven CNAs and cnLOH were observed in the ameloblastomas and six CNAs in the AC. Seven of the CNAs were rare (six in UA and one in MA), four of them encompassing genes (gains of 7q11.21, 1q32......: Ameloblastomas show rare CNAs and cnLOH, presenting a specific genomic profile with no overlapping of the rare alterations among UA, MA, and AC. These genomic changes might play a role in tumor evolution and in BRAFV600E-negative tumors....

  11. Histotype-specific copy-number alterations in ovarian cancer

    Directory of Open Access Journals (Sweden)

    Huang Ruby YunJu

    2012-10-01

    Full Text Available Abstract Background Epithelial ovarian cancer is characterized by multiple genomic alterations; most are passenger alterations which do not confer tumor growth. Like many cancers, it is a heterogeneous disease and can be broadly categorized into 4 main histotypes of clear cell, endometrioid, mucinous, and serous. To date, histotype-specific copy number alterations have been difficult to elucidate. The difficulty lies in having sufficient sample size in each histotype for statistical analyses. Methods To dissect the heterogeneity of ovarian cancer and identify histotype-specific alterations, we used an in silico hypothesis-driven approach on multiple datasets of epithelial ovarian cancer. Results In concordance with previous studies on global copy number alterations landscape, the study showed similar alterations. However, when the landscape was de-convoluted into histotypes, distinct alterations were observed. We report here significant histotype-specific copy number alterations in ovarian cancer and showed that there is genomic diversity amongst the histotypes. 76 cancer genes were found to be significantly altered with several as potential copy number drivers, including ERBB2 in mucinous, and TPM3 in endometrioid histotypes. ERBB2 was found to have preferential alterations, where it was amplified in mucinous (28.6% but deleted in serous tumors (15.1%. Validation of ERBB2 expression showed significant correlation with microarray data (p=0.007. There also appeared to be reciprocal relationship between KRAS mutation and copy number alterations. In mucinous tumors where KRAS mutation is common, the gene was not significantly altered. However, KRAS was significantly amplified in serous tumors where mutations are rare in high grade tumors. Conclusions The study demonstrates that the copy number landscape is specific to the histotypes and identification of these alterations can pave the way for targeted drug therapy specific to the histotypes.

  12. High-throughput genotyping of copy number variation in glutathione S-transferases M1 and T1 using real-time PCR in 20,687 individuals

    DEFF Research Database (Denmark)

    Norskov, M.S.; Frikke-Schmidt, R.; Loft, S.;

    2009-01-01

    OBJECTIVES: Characteristic for the genes encoding glutathione S-transferase (GST) M1 and GSTT1 is a null allele, suggested to increase susceptibility to chronic diseases. We report an optimized method for the determination of copy number variation (CNV) in GST genes. DESIGN AND METHODS: Real...... to 100 ng. In a general population sample of 20,687 individuals the genotype frequencies were concordant with other methods used as standards. Throughput was 4600 genotypes per day at a reagent price of 0.5 euros per sample. CONCLUSIONS: This high-throughput, low cost method accurately determines CNV...

  13. Schizophrenia copy number variants and associative learning

    Science.gov (United States)

    Clifton, N E; Pocklington, A J; Scholz, B; Rees, E; Walters, J T R; Kirov, G; O'Donovan, M C; Owen, M J; Wilkinson, L S; Thomas, K L; Hall, J

    2017-01-01

    Large-scale genomic studies have made major progress in identifying genetic risk variants for schizophrenia. A key finding from these studies is that there is an increased burden of genomic copy number variants (CNVs) in schizophrenia cases compared with controls. The mechanism through which these CNVs confer risk for the symptoms of schizophrenia, however, remains unclear. One possibility is that schizophrenia risk CNVs impact basic associative learning processes, abnormalities of which have long been associated with the disorder. To investigate whether genes in schizophrenia CNVs impact on specific phases of associative learning we combined human genetics with experimental gene expression studies in animals. In a sample of 11 917 schizophrenia cases and 16 416 controls, we investigated whether CNVs from patients with schizophrenia are enriched for genes expressed during the consolidation, retrieval or extinction of associative memories. We show that CNVs from cases are enriched for genes expressed during fear extinction in the hippocampus, but not genes expressed following consolidation or retrieval. These results suggest that CNVs act to impair inhibitory learning in schizophrenia, potentially contributing to the development of core symptoms of the disorder. PMID:27956746

  14. MNSs genotyping by MALDI-TOF MS shows high concordance with serology, allows gene copy number testing and reveals new St(a) alleles.

    Science.gov (United States)

    Meyer, Stefan; Vollmert, Caren; Trost, Nadine; Sigurdardottir, Sonja; Portmann, Claudia; Gottschalk, Jochen; Ries, Judith; Markovic, Alexander; Infanti, Laura; Buser, Andreas; Amar El Dusouqui, Soraya; Rigal, Emmanuel; Castelli, Damiano; Weingand, Bettina; Maier, Andreas; Mauvais, Simon M; Sarraj, Amira; Braisch, Monica C; Thierbach, Jutta; Hustinx, Hein; Frey, Beat M; Gassner, Christoph

    2016-08-01

    Results of genotyping with true high-throughput capability for MNSs antigens are underrepresented, probably because of technical issues, due to the high level of nucleotide sequence homology of the paralogous genes GYPA, GYPB and GYPE. Eight MNSs-specific single nucleotide polymorphisms (SNP) were detected using matrix-assisted laser desorption/ionization, time-of-flight mass spectrometry (MALDI-TOF MS) in 5800 serologically M/N and S/s pre-typed Swiss blood donors and 50 individuals of known or presumptive black African ethnicity. Comparison of serotype with genotype delivered concordance rates of 99·70% and 99·90% and accuracy of genotyping alone of 99·88% and 99·95%, for M/N and S/s, respectively. The area under the curve of peak signals was measured in intron 1 of the two highly homologous genes GYPB and GYPE and allowed for gene copy number variation estimates in all individuals investigated. Elevated GYPB:GYPE ratios accumulated in several carriers of two newly observed GYP*401 variants, termed type G and H, both encoding for the low incidence antigen St(a). In black Africans, reduced GYPB gene contents were proven in pre-typed S-s-U- phenotypes and could be reproduced in unknown specimens. Quantitative gene copy number estimates represented a highly attractive supplement to conventional genotyping, solely based on MNSs SNPs. © 2016 John Wiley & Sons Ltd.

  15. High Quality Genomic Copy Number Data from Archival Formalin-Fixed Paraffin-Embedded Leiomyosarcoma: Optimisation of Universal Linkage System Labelling

    Science.gov (United States)

    Salawu, Abdulazeez; Ul-Hassan, Aliya; Hammond, David; Fernando, Malee; Reed, Malcolm; Sisley, Karen

    2012-01-01

    Most soft tissue sarcomas are characterized by genetic instability and frequent genomic copy number aberrations that are not subtype-specific. Oligonucleotide microarray-based Comparative Genomic Hybridisation (array CGH) is an important technique used to map genome-wide copy number aberrations, but the traditional requirement for high-quality DNA typically obtained from fresh tissue has limited its use in sarcomas. Although large archives of Formalin-fixed Paraffin-embedded (FFPE) tumour samples are available for research, the degradative effects of formalin on DNA from these tissues has made labelling and analysis by array CGH technically challenging. The Universal Linkage System (ULS) may be used for a one-step chemical labelling of such degraded DNA. We have optimised the ULS labelling protocol to perform aCGH on archived FFPE leiomyosarcoma tissues using the 180k Agilent platform. Preservation age of samples ranged from a few months to seventeen years and the DNA showed a wide range of degradation (when visualised on agarose gels). Consistently high DNA labelling efficiency and low microarray probe-to-probe variation (as measured by the derivative log ratio spread) was seen. Comparison of paired fresh and FFPE samples from identical tumours showed good correlation of CNAs detected. Furthermore, the ability to macro-dissect FFPE samples permitted the detection of CNAs that were masked in fresh tissue. Aberrations were visually confirmed using Fluorescence in situ Hybridisation. These results suggest that archival FFPE tissue, with its relative abundance and attendant clinical data may be used for effective mapping for genomic copy number aberrations in such rare tumours as leiomyosarcoma and potentially unravel clues to tumour origins, progression and ultimately, targeted treatment. PMID:23209738

  16. High quality genomic copy number data from archival formalin-fixed paraffin-embedded leiomyosarcoma: optimisation of universal linkage system labelling.

    Science.gov (United States)

    Salawu, Abdulazeez; Ul-Hassan, Aliya; Hammond, David; Fernando, Malee; Reed, Malcolm; Sisley, Karen

    2012-01-01

    Most soft tissue sarcomas are characterized by genetic instability and frequent genomic copy number aberrations that are not subtype-specific. Oligonucleotide microarray-based Comparative Genomic Hybridisation (array CGH) is an important technique used to map genome-wide copy number aberrations, but the traditional requirement for high-quality DNA typically obtained from fresh tissue has limited its use in sarcomas. Although large archives of Formalin-fixed Paraffin-embedded (FFPE) tumour samples are available for research, the degradative effects of formalin on DNA from these tissues has made labelling and analysis by array CGH technically challenging. The Universal Linkage System (ULS) may be used for a one-step chemical labelling of such degraded DNA. We have optimised the ULS labelling protocol to perform aCGH on archived FFPE leiomyosarcoma tissues using the 180k Agilent platform. Preservation age of samples ranged from a few months to seventeen years and the DNA showed a wide range of degradation (when visualised on agarose gels). Consistently high DNA labelling efficiency and low microarray probe-to-probe variation (as measured by the derivative log ratio spread) was seen. Comparison of paired fresh and FFPE samples from identical tumours showed good correlation of CNAs detected. Furthermore, the ability to macro-dissect FFPE samples permitted the detection of CNAs that were masked in fresh tissue. Aberrations were visually confirmed using Fluorescence in situ Hybridisation. These results suggest that archival FFPE tissue, with its relative abundance and attendant clinical data may be used for effective mapping for genomic copy number aberrations in such rare tumours as leiomyosarcoma and potentially unravel clues to tumour origins, progression and ultimately, targeted treatment.

  17. High quality genomic copy number data from archival formalin-fixed paraffin-embedded leiomyosarcoma: optimisation of universal linkage system labelling.

    Directory of Open Access Journals (Sweden)

    Abdulazeez Salawu

    Full Text Available Most soft tissue sarcomas are characterized by genetic instability and frequent genomic copy number aberrations that are not subtype-specific. Oligonucleotide microarray-based Comparative Genomic Hybridisation (array CGH is an important technique used to map genome-wide copy number aberrations, but the traditional requirement for high-quality DNA typically obtained from fresh tissue has limited its use in sarcomas. Although large archives of Formalin-fixed Paraffin-embedded (FFPE tumour samples are available for research, the degradative effects of formalin on DNA from these tissues has made labelling and analysis by array CGH technically challenging. The Universal Linkage System (ULS may be used for a one-step chemical labelling of such degraded DNA. We have optimised the ULS labelling protocol to perform aCGH on archived FFPE leiomyosarcoma tissues using the 180k Agilent platform. Preservation age of samples ranged from a few months to seventeen years and the DNA showed a wide range of degradation (when visualised on agarose gels. Consistently high DNA labelling efficiency and low microarray probe-to-probe variation (as measured by the derivative log ratio spread was seen. Comparison of paired fresh and FFPE samples from identical tumours showed good correlation of CNAs detected. Furthermore, the ability to macro-dissect FFPE samples permitted the detection of CNAs that were masked in fresh tissue. Aberrations were visually confirmed using Fluorescence in situ Hybridisation. These results suggest that archival FFPE tissue, with its relative abundance and attendant clinical data may be used for effective mapping for genomic copy number aberrations in such rare tumours as leiomyosarcoma and potentially unravel clues to tumour origins, progression and ultimately, targeted treatment.

  18. Copy number variation in the horse genome.

    Directory of Open Access Journals (Sweden)

    Sharmila Ghosh

    2014-10-01

    Full Text Available We constructed a 400K WG tiling oligoarray for the horse and applied it for the discovery of copy number variations (CNVs in 38 normal horses of 16 diverse breeds, and the Przewalski horse. Probes on the array represented 18,763 autosomal and X-linked genes, and intergenic, sub-telomeric and chrY sequences. We identified 258 CNV regions (CNVRs across all autosomes, chrX and chrUn, but not in chrY. CNVs comprised 1.3% of the horse genome with chr12 being most enriched. American Miniature horses had the highest and American Quarter Horses the lowest number of CNVs in relation to Thoroughbred reference. The Przewalski horse was similar to native ponies and draft breeds. The majority of CNVRs involved genes, while 20% were located in intergenic regions. Similar to previous studies in horses and other mammals, molecular functions of CNV-associated genes were predominantly in sensory perception, immunity and reproduction. The findings were integrated with previous studies to generate a composite genome-wide dataset of 1476 CNVRs. Of these, 301 CNVRs were shared between studies, while 1174 were novel and require further validation. Integrated data revealed that to date, 41 out of over 400 breeds of the domestic horse have been analyzed for CNVs, of which 11 new breeds were added in this study. Finally, the composite CNV dataset was applied in a pilot study for the discovery of CNVs in 6 horses with XY disorders of sexual development. A homozygous deletion involving AKR1C gene cluster in chr29 in two affected horses was considered possibly causative because of the known role of AKR1C genes in testicular androgen synthesis and sexual development. While the findings improve and integrate the knowledge of CNVs in horses, they also show that for effective discovery of variants of biomedical importance, more breeds and individuals need to be analyzed using comparable methodological approaches.

  19. Copy number variation in the horse genome.

    Science.gov (United States)

    Ghosh, Sharmila; Qu, Zhipeng; Das, Pranab J; Fang, Erica; Juras, Rytis; Cothran, E Gus; McDonell, Sue; Kenney, Daniel G; Lear, Teri L; Adelson, David L; Chowdhary, Bhanu P; Raudsepp, Terje

    2014-10-01

    We constructed a 400K WG tiling oligoarray for the horse and applied it for the discovery of copy number variations (CNVs) in 38 normal horses of 16 diverse breeds, and the Przewalski horse. Probes on the array represented 18,763 autosomal and X-linked genes, and intergenic, sub-telomeric and chrY sequences. We identified 258 CNV regions (CNVRs) across all autosomes, chrX and chrUn, but not in chrY. CNVs comprised 1.3% of the horse genome with chr12 being most enriched. American Miniature horses had the highest and American Quarter Horses the lowest number of CNVs in relation to Thoroughbred reference. The Przewalski horse was similar to native ponies and draft breeds. The majority of CNVRs involved genes, while 20% were located in intergenic regions. Similar to previous studies in horses and other mammals, molecular functions of CNV-associated genes were predominantly in sensory perception, immunity and reproduction. The findings were integrated with previous studies to generate a composite genome-wide dataset of 1476 CNVRs. Of these, 301 CNVRs were shared between studies, while 1174 were novel and require further validation. Integrated data revealed that to date, 41 out of over 400 breeds of the domestic horse have been analyzed for CNVs, of which 11 new breeds were added in this study. Finally, the composite CNV dataset was applied in a pilot study for the discovery of CNVs in 6 horses with XY disorders of sexual development. A homozygous deletion involving AKR1C gene cluster in chr29 in two affected horses was considered possibly causative because of the known role of AKR1C genes in testicular androgen synthesis and sexual development. While the findings improve and integrate the knowledge of CNVs in horses, they also show that for effective discovery of variants of biomedical importance, more breeds and individuals need to be analyzed using comparable methodological approaches.

  20. Genome-wide copy number profiling on high-density bacterial artificial chromosomes, single-nucleotide polymorphisms, and oligonucleotide microarrays: a platform comparison based on statistical power analysis.

    NARCIS (Netherlands)

    Hehir-Kwa, J.Y.; Egmont-Peterson, M.; Janssen, I.M.; Smeets, D.F.C.M.; Geurts van Kessel, A.H.M.; Veltman, J.A.

    2007-01-01

    Recently, comparative genomic hybridization onto bacterial artificial chromosome (BAC) arrays (array-based comparative genomic hybridization) has proved to be successful for the detection of submicroscopic DNA copy-number variations in health and disease. Technological improvements to achieve a

  1. Endogenous RNA interference is driven by copy number

    Science.gov (United States)

    Cruz, Cristina; Houseley, Jonathan

    2014-01-01

    A plethora of non-protein coding RNAs are produced throughout eukaryotic genomes, many of which are transcribed antisense to protein-coding genes and could potentially instigate RNA interference (RNAi) responses. Here we have used a synthetic RNAi system to show that gene copy number is a key factor controlling RNAi for transcripts from endogenous loci, since transcripts from multi-copy loci form double stranded RNA more efficiently than transcripts from equivalently expressed single-copy loci. Selectivity towards transcripts from high-copy DNA is therefore an emergent property of a minimal RNAi system. The ability of RNAi to selectively degrade transcripts from high-copy loci would allow suppression of newly emerging transposable elements, but such a surveillance system requires transcription. We show that low-level genome-wide pervasive transcription is sufficient to instigate RNAi, and propose that pervasive transcription is part of a defense mechanism capable of directing a sequence-independent RNAi response against transposable elements amplifying within the genome. DOI: http://dx.doi.org/10.7554/eLife.01581.001 PMID:24520161

  2. Endogenous RNA interference is driven by copy number.

    Science.gov (United States)

    Cruz, Cristina; Houseley, Jonathan

    2014-02-11

    A plethora of non-protein coding RNAs are produced throughout eukaryotic genomes, many of which are transcribed antisense to protein-coding genes and could potentially instigate RNA interference (RNAi) responses. Here we have used a synthetic RNAi system to show that gene copy number is a key factor controlling RNAi for transcripts from endogenous loci, since transcripts from multi-copy loci form double stranded RNA more efficiently than transcripts from equivalently expressed single-copy loci. Selectivity towards transcripts from high-copy DNA is therefore an emergent property of a minimal RNAi system. The ability of RNAi to selectively degrade transcripts from high-copy loci would allow suppression of newly emerging transposable elements, but such a surveillance system requires transcription. We show that low-level genome-wide pervasive transcription is sufficient to instigate RNAi, and propose that pervasive transcription is part of a defense mechanism capable of directing a sequence-independent RNAi response against transposable elements amplifying within the genome. DOI: http://dx.doi.org/10.7554/eLife.01581.001.

  3. Ribosomal DNA copy number loss and sequence variation in cancer.

    Science.gov (United States)

    Xu, Baoshan; Li, Hua; Perry, John M; Singh, Vijay Pratap; Unruh, Jay; Yu, Zulin; Zakari, Musinu; McDowell, William; Li, Linheng; Gerton, Jennifer L

    2017-06-01

    Ribosomal DNA is one of the most variable regions in the human genome with respect to copy number. Despite the importance of rDNA for cellular function, we know virtually nothing about what governs its copy number, stability, and sequence in the mammalian genome due to challenges associated with mapping and analysis. We applied computational and droplet digital PCR approaches to measure rDNA copy number in normal and cancer states in human and mouse genomes. We find that copy number and sequence can change in cancer genomes. Counterintuitively, human cancer genomes show a loss of copies, accompanied by global copy number co-variation. The sequence can also be more variable in the cancer genome. Cancer genomes with lower copies have mutational evidence of mTOR hyperactivity. The PTEN phosphatase is a tumor suppressor that is critical for genome stability and a negative regulator of the mTOR kinase pathway. Surprisingly, but consistent with the human cancer genomes, hematopoietic cancer stem cells from a Pten-/- mouse model for leukemia have lower rDNA copy number than normal tissue, despite increased proliferation, rRNA production, and protein synthesis. Loss of copies occurs early and is associated with hypersensitivity to DNA damage. Therefore, copy loss is a recurrent feature in cancers associated with mTOR activation. Ribosomal DNA copy number may be a simple and useful indicator of whether a cancer will be sensitive to DNA damaging treatments.

  4. Physical state & copy number of high risk human papillomavirus type 16 DNA in progression of cervical cancer

    Directory of Open Access Journals (Sweden)

    Shirish Shukla

    2014-01-01

    Full Text Available Background & objectives: High-risk human papilloma virus (HR-HPV infection and its integration in host genome is a key event in malignant transformation of cervical cells. HPV16 being a dominant HR-HPV type, we undertook this study to analyze if viral load and physical state of the virus correlated with each other in the absence of other confounding variables and examined their potential as predictors of progressive cervical lesions. Methods: Both, viral load and integration status of HPV16 were determined by real time URR PCR and estimation of E2:E6 ratio in a total of 130 PGMY-RLB -confirmed, monotypic HPV16-infected cervical DNA samples from biopsies of cytology-confirmed low grade (LSIL, 30 and high grade (HSIL, 30, and invasive carcinoma, (squamous cell carcinoma SCC, 70 cases. Results: Investigation of DNA samples revealed a gradual increase in HPV16 viral load over several magnitudes and increased frequency of integration from LSIL to HSIL and HSIL to invasive cancer in relation to the severity of lesions in monotypic HPV16-infected cervical tissues. In a substantial number of precancer (11/60 and cancer cases (29/70, HPV16 was detected in concomitant mixed form. The concomitant form of HPV16 genome carried significantly higher viral load. Interpretation & conclusions: Overall, viral load and integration increased with disease severity and could be useful biomarkers in disease progression, at least, in HPV16-infected cervical pre-cancer and cancer lesions.

  5. Copy Number Variation at the APOL1 Locus.

    Directory of Open Access Journals (Sweden)

    Rupam Ruchi

    Full Text Available Two coding variants in the APOL1 gene (G1 and G2 explain most of the high rate of kidney disease in African Americans. APOL1-associated kidney disease risk inheritance follows an autosomal recessive pattern: The relative risk of kidney disease associated with inheritance of two high-risk variants is 7-30 fold, depending on the specific kidney phenotype. We wished to determine if the variability in phenotype might in part reflect structural differences in APOL1 gene. We analyzed sequence coverage from 1000 Genomes Project Phase 3 samples as well as exome sequencing data from African American kidney disease cases for copy number variation. 8 samples sequenced in the 1000 Genomes Project showed increased coverage over a ~100kb region that includes APOL2, APOL1 and part of MYH9, suggesting the presence of APOL1 copy number greater than 2. We reasoned that such duplications should be enriched in apparent G1 heterozygotes with kidney disease. Using a PCR-based assay, we observed the presence of this duplication in additional samples from apparent G0G1 or G0G2 individuals. The frequency of this APOL1 duplication was compared among cases (n = 123 and controls (n = 255 with apparent G0G1 heterozygosity. The presence of APOL1 duplication was observed in 4.06% of cases and 0.78% controls, preliminary evidence that this APOL1 duplication may alter susceptibility to kidney disease (p = 0.03. Taqman-based copy number assays confirmed the presence of 3 APOL1 copies in individuals positive for this specific duplication by PCR assay, but also identified a small number of individuals with additional APOL1 copies of presumably different structure. These observations motivate further studies to better assess the contribution of APOL1 copy number on kidney disease risk and on APOL1 function. Investigators and clinicians genotyping APOL1 should also consider whether the particular genotyping platform used is subject to technical errors when more than two copies of

  6. Chimera-free, high copy number YAC libraries and efficient methods of analysis. Final technical progress report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-10-01

    The first experiment involved a low chimera YAC library in recombination deficient host strains. To determine if the genetic background of the yeast host strain contributes to the formation of chimeric YACs the same YAC ligation mixture was introduced into three isogenic yeast hosts differing only in their recombination abilities. To prepare YACs, human genomic DNA was partially digested with EcoR1 and then ligated to YAC vector pCGS966 arms. DNA was size fractionated before and after ligation by preparative pulsed field gel electrophoresis (CHEF), selecting for fragments greater than 400 kb, and introduced into competent spheroplasts. CHEF gel Southern blots of resulting colony-purified YACs were probed with human DNA to determine if multiple YACs or YAC fragments were present in the same cell. The frequency of chimeric YACs was measured by fluorescence in situ hybridization (FISH) of YACs to human prometaphase spreads. YACs that hybridized to more than one location were assumed to be chimeric. In the second experiment new YAC vectors featuring tags for capture of YACs and YAC inserts were constructed. Yeast Artificial Chromosomes (YACs) have been of tremendous value in the physical mapping of the human genome. Because they can carry very large inserts, YACs are likely not only to contain entire genes but also their control elements. However, the only mode of purification of YAC DNA from current commonly used YAC libraries such as the CEPH library is by pulsed field gel electrophoresis. This is an inefficient, time consuming process and due to the single copy nature of these YACs, often result in poor yields. The vector pCGS1000 was designed to test new efficient ways of YAC DNA purification.

  7. Chimera-free, high copy number YAC libraries and efficient methods of analysis. Final technical progress report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-10-01

    The first experiment involved a low chimera YAC library in recombination deficient host strains. To determine if the genetic background of the yeast host strain contributes to the formation of chimeric YACs the same YAC ligation mixture was introduced into three isogenic yeast hosts differing only in their recombination abilities. To prepare YACs, human genomic DNA was partially digested with EcoR1 and then ligated to YAC vector pCGS966 arms. DNA was size fractionated before and after ligation by preparative pulsed field gel electrophoresis (CHEF), selecting for fragments greater than 400 kb, and introduced into competent spheroplasts. CHEF gel Southern blots of resulting colony-purified YACs were probed with human DNA to determine if multiple YACs or YAC fragments were present in the same cell. The frequency of chimeric YACs was measured by fluorescence in situ hybridization (FISH) of YACs to human prometaphase spreads. YACs that hybridized to more than one location were assumed to be chimeric. In the second experiment new YAC vectors featuring tags for capture of YACs and YAC inserts were constructed. Yeast Artificial Chromosomes (YACs) have been of tremendous value in the physical mapping of the human genome. Because they can carry very large inserts, YACs are likely not only to contain entire genes but also their control elements. However, the only mode of purification of YAC DNA from current commonly used YAC libraries such as the CEPH library is by pulsed field gel electrophoresis. This is an inefficient, time consuming process and due to the single copy nature of these YACs, often result in poor yields. The vector pCGS1000 was designed to test new efficient ways of YAC DNA purification.

  8. Are there any more ovarian tumor suppressor genes? A new perspective using ultra high-resolution copy number and loss of heterozygosity analysis.

    Science.gov (United States)

    Gorringe, Kylie L; Ramakrishna, Manasa; Williams, Louise H; Sridhar, Anita; Boyle, Samantha E; Bearfoot, Jennifer L; Li, Jason; Anglesio, Michael S; Campbell, Ian G

    2009-10-01

    Ovarian cancer is characterized by complex genetic alterations, including copy number loss and copy number-neutral loss of heterozygosity (LOH). These alterations are assumed to represent the "second hit" of the underlying tumor suppressor gene (TSG), however, relative to the number of LOH hotspots reported, few ovarian TSGs have been identified. We conducted a high-resolution LOH analysis using SNP arrays (500K and SNP6.0) of 106 primary ovarian tumors of various histological subtypes together with matching normal DNA. LOH was detected in at least 35% of samples on chromosomes 17, 19p, 22q, Xp, 13q, 8p, 6q, 4q, 5q, 1p, 16q, and 9q with a median minimal region of overlap of only 300 kb. Subtype-specific differences in LOH frequency were noted, particularly for mucinous cases. We also identified 192 somatic homozygous deletions (HDs). Recurrent HDs targeted known TSGs such as CDKN2A (eight samples), RB1 (five samples), and PTEN (three samples). Additional recurrent HDs targeted 16 candidate TSGs near minimal regions of LOH on chromosomes 17, 13, 8p, 5q, and X. Given the importance of HDs in inactivating known genes, these candidates are highly likely to be ovarian TSGs. Our data suggest that the poor success of previous LOH studies was due to the inability of previous technology to resolve complex genomic alterations and distinguish true LOH from allelic imbalance. This study shows that recurrent regions of LOH and HD frequently align with known TSGs suggesting that LOH analysis remains a valid approach to discovering new candidates.

  9. Identification of rare high-risk copy number variants affecting the dopamine transporter gene in mental disorders

    DEFF Research Database (Denmark)

    Hoeffding, Louise K; Duong, Linh T T; Ingason, Andrés;

    2015-01-01

    BACKGROUND: The dopamine transporter, also known as solute carrier 6A3 (SLC6A3), plays an important role in synaptic transmission by regulating the reuptake of dopamine in the synapses. In line with this, variations in the gene encoding this transporter have been linked to both schizophrenia...... rare high-risk variants of psychiatric disorders. METHODS: We performed a systematic screening for CNVs affecting SLC6A3 in 761 healthy controls, 672 schizophrenia patients, and 194 patients with bipolar disorder in addition to 253 family members from six large pedigrees affected by mental disorders...... sizes and two affected several genes in addition to SLC6A3. CONCLUSION: Our findings suggest that rare high-risk CNVs affecting the gene encoding the dopamine transporter contribute to the pathogenesis of schizophrenia and affective disorders....

  10. High-resolution copy number profiling by array CGH using DNA isolated from formalin-fixed, paraffin-embedded tissues.

    Science.gov (United States)

    van Essen, Hendrik F; Ylstra, Bauke

    2012-01-01

    We describe protocols to acquire high-quality DNA from formalin-fixed, paraffin-embedded (FFPE) tissues for the use in array comparative genome hybridization (CGH). Formalin fixation combined with paraffin embedding is routine procedure for solid malignancies in the diagnostic practice of the pathologist. As a consequence, large archives of FFPE tissues are available in pathology institutes across the globe. This archival material is for many research questions an invaluable resource, with long-term clinical follow-up and survival data available. FFPE is, thus, highly attractive for large genomics studies, including experiments requiring samples for test/learning and validation. Most larger array CGH studies have, therefore, made use of FFPE material and show that CNAs have tumor- and tissue-specific traits (Chin et al. Cancer Cell 10: 529-541, 2006; Fridlyand et al. BMC Cancer 6: 96, 2006; Weiss et al. Oncogene 22: 1872-1879, 2003; Jong et al. Oncogene 26: 1499-1506, 2007). The protocols described are tailored to array CGH of FFPE solid malignancies: from sectioning FFPE blocks to specific cynosures for pathological revisions of sections, DNA isolation, quality testing, and amplification. The protocols are technical in character and elaborate up to the labeling of isolated DNA while further processes and interpretation and data analysis are beyond the scope.

  11. Large multi-allelic copy number variations in humans

    Science.gov (United States)

    Handsaker, Robert E.; Van Doren, Vanessa; Berman, Jennifer R.; Genovese, Giulio; Kashin, Seva; Boettger, Linda M.; McCarroll, Steven A.

    2015-01-01

    Thousands of genome segments appear to be present in widely varying copy number in different human genomes. We developed ways to use increasingly abundant whole genome sequence data to identify the copy numbers, alleles and haplotypes present at most large, multi-allelic CNVs (mCNVs). We analyzed 849 genomes sequenced by the 1000 Genomes Project to identify most large (>5 kb) mCNVs, including 3,878 duplications, of which 1,356 appear to have three or more segregating alleles. We find that mCNVs give rise to most human gene-dosage variation – exceeding sevenfold the contribution of deletions and biallelic duplications – and that this variation in gene dosage generates abundant variation in gene expression. We describe “runaway duplication haplotypes” in which genes, including HPR and ORM1, have mutated to high copy number on specific haplotypes. We describe partially successful initial strategies for analyzing mCNVs via imputation and provide an initial data resource to support such analyses. PMID:25621458

  12. CNARA: reliability assessment for genomic copy number profiles.

    Science.gov (United States)

    Ai, Ni; Cai, Haoyang; Solovan, Caius; Baudis, Michael

    2016-10-12

    DNA copy number profiles from microarray and sequencing experiments sometimes contain wave artefacts which may be introduced during sample preparation and cannot be removed completely by existing preprocessing methods. Besides, large derivative log ratio spread (DLRS) of the probes correlating with poor DNA quality is sometimes observed in genome screening experiments and may lead to unreliable copy number profiles. Depending on the extent of these artefacts and the resulting misidentification of copy number alterations/variations (CNA/CNV), it may be desirable to exclude such samples from analyses or to adapt the downstream data analysis strategy accordingly. Here, we propose a method to distinguish reliable genomic copy number profiles from those containing heavy wave artefacts and/or large DLRS. We define four features that adequately summarize the copy number profiles for reliability assessment, and train a classifier on a dataset of 1522 copy number profiles from various microarray platforms. The method can be applied to predict the reliability of copy number profiles irrespective of the underlying microarray platform and may be adapted for those sequencing platforms from which copy number estimates could be computed as a piecewise constant signal. Further details can be found at https://github.com/baudisgroup/CNARA . We have developed a method for the assessment of genomic copy number profiling data, and suggest to apply the method in addition to and after other state-of-the-art noise correction and quality control procedures. CNARA could be instrumental in improving the assessment of data used for genomic data mining experiments and support the reliable functional attribution of copy number aberrations especially in cancer research.

  13. High-throughput genotyping of copy number variation in glutathione S-transferases M1 and T1 using real-time PCR in 20,687 individuals

    DEFF Research Database (Denmark)

    Norskov, M.S.; Frikke-Schmidt, R.; Loft, S.;

    2009-01-01

    OBJECTIVES: Characteristic for the genes encoding glutathione S-transferase (GST) M1 and GSTT1 is a null allele, suggested to increase susceptibility to chronic diseases. We report an optimized method for the determination of copy number variation (CNV) in GST genes. DESIGN AND METHODS: Real-time...

  14. High copy number variation of cancer-related microRNA genes and frequent amplification of DICER1 and DROSHA in lung cancer

    Science.gov (United States)

    Czubak, Karol; Lewandowska, Marzena Anna; Klonowska, Katarzyna; Roszkowski, Krzysztof; Kowalewski, Janusz; Figlerowicz, Marek; Kozlowski, Piotr

    2015-01-01

    A growing body of evidence indicates that miRNAs may be a class of genetic elements that can either drive or suppress oncogenesis. In this study we analyzed the somatic copy number variation of 14 miRNA genes frequently found to be either over- or underexpressed in lung cancer, as well as two miRNA biogenesis genes, DICER1 and DROSHA, in non-small-cell lung cancer (NSCLC). Our analysis showed that most analyzed miRNA genes undergo substantial copy number alteration in lung cancer. The most frequently amplified miRNA genes include the following: miR-30d, miR-21, miR-17 and miR-155. We also showed that both DICER1 and DROSHA are frequently amplified in NSCLC. The copy number variation of DICER1 and DROSHA correlates well with their expression and survival of NSCLC and other cancer patients. The increased expression of DROSHA and DICER1 decreases and increases the survival, respectively. In conclusion, our results show that copy number variation may be an important mechanism of upregulation/downregulation of miRNAs in cancer and suggest an oncogenic role for DROSHA. PMID:26156018

  15. Genome Architecture and Its Roles in Human Copy Number Variation

    Directory of Open Access Journals (Sweden)

    Lu Chen

    2014-12-01

    Full Text Available Besides single-nucleotide variants in the human genome, large-scale genomic variants, such as copy number variations (CNVs, are being increasingly discovered as a genetic source of human diversity and the pathogenic factors of diseases. Recent experimental findings have shed light on the links between different genome architectures and CNV mutagenesis. In this review, we summarize various genomic features and discuss their contributions to CNV formation. Genomic repeats, including both low-copy and high-copy repeats, play important roles in CNV instability, which was initially known as DNA recombination events. Furthermore, it has been found that human genomic repeats can also induce DNA replication errors and consequently result in CNV mutations. Some recent studies showed that DNA replication timing, which reflects the high-order information of genomic organization, is involved in human CNV mutations. Our review highlights that genome architecture, from DNA sequence to high-order genomic organization, is an important molecular factor in CNV mutagenesis and human genomic instability.

  16. Mitochondrial DNA copy number in peripheral blood and melanoma risk.

    Directory of Open Access Journals (Sweden)

    Jie Shen

    Full Text Available Mitochondrial DNA (mtDNA copy number in peripheral blood has been suggested as risk modifier in various types of cancer. However, its influence on melanoma risk is unclear. We evaluated the association between mtDNA copy number in peripheral blood and melanoma risk in 500 melanoma cases and 500 healthy controls from an ongoing melanoma study. The mtDNA copy number was measured using real-time polymerase chain reaction. Overall, mean mtDNA copy number was significantly higher in cases than in controls (1.15 vs 0.99, P<0.001. Increased mtDNA copy number was associated with a 1.45-fold increased risk of melanoma (95% confidence interval: 1.12-1.97. Significant joint effects between mtDNA copy number and variables related to pigmentation and history of sunlight exposure were observed. This study supports an association between increased mtDNA copy number and melanoma risk that is independent on the known melanoma risk factors (pigmentation and history of sunlight exposure.

  17. Molecular methods for genotyping complex copy number polymorphisms.

    Science.gov (United States)

    Cantsilieris, Stuart; Baird, Paul N; White, Stefan J

    2013-02-01

    Genome structural variation shows remarkable complexity with respect to copy number, sequence content and distribution. While the discovery of copy number polymorphisms (CNP) has increased exponentially in recent years, the transition from discovery to genotyping has proved challenging, particularly for CNPs embedded in complex regions of the genome. CNPs that are collectively common in the population and possess a dynamic range of copy numbers have proved the most difficult to genotype in association studies. This is in some part due to technical limitations of genotyping assays and the sequence properties of the genomic region being analyzed. Here we describe in detail the basis of a number of molecular techniques used to genotype complex CNPs, compare and contrast these approaches for determination of multi-allelic copy number, and discuss the potential application of these techniques in genetic studies.

  18. Stable high-copy-number integration of Aspergillus oryzae alpha-AMYLASE cDNA in an industrial baker's yeast strain.

    Science.gov (United States)

    Nieto, A; Prieto, J A; Sanz, P

    1999-01-01

    The Aspergillus oryzae alpha-amylase cDNA was placed under the control of the Saccharomyces cerevisiae actin promoter (pACT1) and introduced into the ribosomal DNA locus of an industrial baker's yeast strain. To obtain a strain eligible for commercial use, we constructed an integrative cassette lacking bacterial DNA sequences but containing the alpha-amylase cDNA and ribosomal DNA sequences to target the integration to this locus. High-copy-number integrants were obtained including a defective TRP1d promoter in the integrative cassette. We selected one transformant, Rib-AMY (CECT10872), in which the multi-integrated sequences were stable even after 200 generations of growth in nonselective medium. This transformant also expressed and secreted high levels of alpha-amylase. Bread made with this strain had a higher volume, lower density, and softer crumbs than bread made with a control strain. The Rib-AMY transformant also was useful in retarding bread firming. This new strain fulfills all the requirements for commercial utilization and should reduce or eliminate the requirement for addition of exogenous alpha-amylase to the flour, reducing allergenic work-related symptoms due to this enzyme.

  19. DNA replication stress restricts ribosomal DNA copy number.

    Science.gov (United States)

    Salim, Devika; Bradford, William D; Freeland, Amy; Cady, Gillian; Wang, Jianmin; Pruitt, Steven C; Gerton, Jennifer L

    2017-09-15

    Ribosomal RNAs (rRNAs) in budding yeast are encoded by ~100-200 repeats of a 9.1kb sequence arranged in tandem on chromosome XII, the ribosomal DNA (rDNA) locus. Copy number of rDNA repeat units in eukaryotic cells is maintained far in excess of the requirement for ribosome biogenesis. Despite the importance of the repeats for both ribosomal and non-ribosomal functions, it is currently not known how "normal" copy number is determined or maintained. To identify essential genes involved in the maintenance of rDNA copy number, we developed a droplet digital PCR based assay to measure rDNA copy number in yeast and used it to screen the yeast conditional temperature-sensitive mutant collection of essential genes. Our screen revealed that low rDNA copy number is associated with compromised DNA replication. Further, subculturing yeast under two separate conditions of DNA replication stress selected for a contraction of the rDNA array independent of the replication fork blocking protein, Fob1. Interestingly, cells with a contracted array grew better than their counterparts with normal copy number under conditions of DNA replication stress. Our data indicate that DNA replication stresses select for a smaller rDNA array. We speculate that this liberates scarce replication factors for use by the rest of the genome, which in turn helps cells complete DNA replication and continue to propagate. Interestingly, tumors from mini chromosome maintenance 2 (MCM2)-deficient mice also show a loss of rDNA repeats. Our data suggest that a reduction in rDNA copy number may indicate a history of DNA replication stress, and that rDNA array size could serve as a diagnostic marker for replication stress. Taken together, these data begin to suggest the selective pressures that combine to yield a "normal" rDNA copy number.

  20. Use of ubiquitous, highly heterozygous copy number variants and digital droplet polymerase chain reaction to monitor chimerism after allogeneic haematopoietic stem cell transplantation.

    Science.gov (United States)

    Whitlam, John B; Ling, Ling; Swain, Michael; Harrington, Tom; Mirochnik, Oksana; Brooks, Ian; Cronin, Sara; Challis, Jackie; Petrovic, Vida; Bruno, Damien L; Mechinaud, Francoise; Conyers, Rachel; Slater, Howard

    2017-01-29

    Chimerism analysis has an important role in the management of allogeneic hematopoietic stem cell transplantation. It informs response to disease relapse, graft rejection, and graft-versus-host disease. We have developed a method for chimerism analysis using ubiquitous copy number variation (CNV), which has the benefit of a "negative background" against which multiple independent informative markers are quantified using digital droplet polymerase chain reaction. A panel of up to 38 CNV markers with homozygous deletion frequencies of approximately 0.4-0.6 were used. Sensitivity, precision, reproducibility, and informativity were assessed. CNV chimerism results were compared against established fluorescence in situ hybridization, single nucleotide polymorphism, and short tandem repeat-based methods with excellent correlation. Using 30 ng of input DNA per well, the limit of detection was 0.05% chimerism and the limit of quantification was 0.5% chimerism. High informativity was seen with a median of four informative markers detectable per individual in 39 recipients and 43 donor genomes studied. The strength of this approach was exemplified in a multiple donor case involving four genomes (three related). The precision, sensitivity, and informativity of this approach recommend it for use in clinical practice.

  1. Application of droplet digital PCR to determine copy number of endogenous genes and transgenes in sugarcane.

    Science.gov (United States)

    Sun, Yue; Joyce, Priya Aiyar

    2017-08-28

    Droplet digital PCR combined with the low copy ACT allele as endogenous reference gene, makes accurate and rapid estimation of gene copy number in Q208 (A) and Q240 (A) attainable. Sugarcane is an important cultivated crop with both high polyploidy and aneuploidy in its 10 Gb genome. Without a known copy number reference gene, it is difficult to accurately estimate the copy number of any gene of interest by PCR-based methods in sugarcane. Recently, a new technology, known as droplet digital PCR (ddPCR) has been developed which can measure the absolute amount of the target DNA in a given sample. In this study, we deduced the true copy number of three endogenous genes, actin depolymerizing factor (ADF), adenine phosphoribosyltransferase (APRT) and actin (ACT) in three Australian sugarcane varieties, using ddPCR by comparing the absolute amounts of the above genes with a transgene of known copy number. A single copy of the ACT allele was detected in Q208 (A) , two copies in Q240 (A) , but was absent in Q117. Copy number variation was also observed for both APRT and ADF, and ranged from 9 to 11 in the three tested varieties. Using this newly developed ddPCR method, transgene copy number was successfully determined in 19 transgenic Q208 (A) and Q240 (A) events using ACT as the reference endogenous gene. Our study demonstrates that ddPCR can be used for high-throughput genetic analysis and is a quick, accurate and reliable alternative method for gene copy number determination in sugarcane. This discovered ACT allele would be a suitable endogenous reference gene for future gene copy number variation and dosage studies of functional genes in Q208 (A) and Q240 (A) .

  2. Evolutionary dynamics of copy number variation in pig genomes in the context of adaptation and domestication

    NARCIS (Netherlands)

    Paudel, Y.; Madsen, O.; Megens, H.J.W.C.; Frantz, L.A.F.; Bosse, M.; Bastiaansen, J.W.M.; Crooijmans, R.P.M.A.; Groenen, M.

    2013-01-01

    Background Copy number variable regions (CNVRs) can result in drastic phenotypic differences and may therefore be subject to selection during domestication. Studying copy number variation in relation to domestication is highly relevant in pigs because of their very rich natural and domestication

  3. Evolutionary dynamics of copy number variation in pig genomes in the context of adaptation and domestication

    NARCIS (Netherlands)

    Paudel, Y.; Madsen, O.; Megens, H.J.W.C.; Frantz, L.A.F.; Bosse, M.; Bastiaansen, J.W.M.; Crooijmans, R.P.M.A.; Groenen, M.

    2013-01-01

    Background Copy number variable regions (CNVRs) can result in drastic phenotypic differences and may therefore be subject to selection during domestication. Studying copy number variation in relation to domestication is highly relevant in pigs because of their very rich natural and domestication his

  4. Identification of rare recurrent copy number variants in high-risk autism families and their prevalence in a large ASD population.

    Directory of Open Access Journals (Sweden)

    Nori Matsunami

    Full Text Available Structural variation is thought to play a major etiological role in the development of autism spectrum disorders (ASDs, and numerous studies documenting the relevance of copy number variants (CNVs in ASD have been published since 2006. To determine if large ASD families harbor high-impact CNVs that may have broader impact in the general ASD population, we used the Affymetrix genome-wide human SNP array 6.0 to identify 153 putative autism-specific CNVs present in 55 individuals with ASD from 9 multiplex ASD pedigrees. To evaluate the actual prevalence of these CNVs as well as 185 CNVs reportedly associated with ASD from published studies many of which are insufficiently powered, we designed a custom Illumina array and used it to interrogate these CNVs in 3,000 ASD cases and 6,000 controls. Additional single nucleotide variants (SNVs on the array identified 25 CNVs that we did not detect in our family studies at the standard SNP array resolution. After molecular validation, our results demonstrated that 15 CNVs identified in high-risk ASD families also were found in two or more ASD cases with odds ratios greater than 2.0, strengthening their support as ASD risk variants. In addition, of the 25 CNVs identified using SNV probes on our custom array, 9 also had odds ratios greater than 2.0, suggesting that these CNVs also are ASD risk variants. Eighteen of the validated CNVs have not been reported previously in individuals with ASD and three have only been observed once. Finally, we confirmed the association of 31 of 185 published ASD-associated CNVs in our dataset with odds ratios greater than 2.0, suggesting they may be of clinical relevance in the evaluation of children with ASDs. Taken together, these data provide strong support for the existence and application of high-impact CNVs in the clinical genetic evaluation of children with ASD.

  5. Evolution vs the number of gene copies per primitive cell.

    Science.gov (United States)

    Koch, A L

    1984-01-01

    Computer simulations are presented of the rate at which an advantageous mutant would displace the prototype in a replicating system without an accurate segregation mechanism. If the number of gene copies in the system is indefinitely large, Darwinian evolution is essentially stopped because there is no coupling of phenotype with genotype, i.e., there is no growth advantage to the advantageous gene relative to the prototype and therefore no "survival of the fittest." The inhibition of evolution due to a number of gene copies less than 100 would have been not insurmountable. Although the presence of multiple copies would have allowed replacement by an advantageous mutant, it provided a way for the primitive cell to conserve less immediately useful genes that could evolve into different or more effective genes. This possibility was lost as accurate segregation mechanisms evolved and cells with few copies of each gene, such as modern procaryotes, arose.

  6. Confirmed rare copy number variants implicate novel genes in schizophrenia.

    Science.gov (United States)

    Tam, Gloria W C; van de Lagemaat, Louie N; Redon, Richard; Strathdee, Karen E; Croning, Mike D R; Malloy, Mary P; Muir, Walter J; Pickard, Ben S; Deary, Ian J; Blackwood, Douglas H R; Carter, Nigel P; Grant, Seth G N

    2010-04-01

    Understanding how cognitive processes including learning, memory, decision making and ideation are encoded by the genome is a key question in biology. Identification of sets of genes underlying human mental disorders is a path towards this objective. Schizophrenia is a common disease with cognitive symptoms, high heritability and complex genetics. We have identified genes involved with schizophrenia by measuring differences in DNA copy number across the entire genome in 91 schizophrenia cases and 92 controls in the Scottish population. Our data reproduce rare and common variants observed in public domain data from >3000 schizophrenia cases, confirming known disease loci as well as identifying novel loci. We found copy number variants in PDE10A (phosphodiesterase 10A), CYFIP1 [cytoplasmic FMR1 (Fragile X mental retardation 1)-interacting protein 1], K(+) channel genes KCNE1 and KCNE2, the Down's syndrome critical region 1 gene RCAN1 (regulator of calcineurin 1), cell-recognition protein CHL1 (cell adhesion molecule with homology with L1CAM), the transcription factor SP4 (specificity protein 4) and histone deacetylase HDAC9, among others (see http://www.genes2cognition.org/SCZ-CNV). Integrating the function of these many genes into a coherent model of schizophrenia and cognition is a major unanswered challenge.

  7. Copy number variations exploration of multiple genes in Graves' disease.

    Science.gov (United States)

    Song, Rong-Hua; Shao, Xiao-Qing; Li, Ling; Wang, Wen; Zhang, Jin-An

    2017-01-01

    Few previous published papers reported copy number variations of genes could affect the predisposition of Graves' disease (GD). Herein, the aim of this study was to explore the association between copy number variations (CNV) profile and GD. The preliminary copy number microarray used to screen copy number variant genes was performed in 6 GD patients. Five CNV candidate genes (CFH, CFHR1, KIAA0125, UGT2B15, and UGT2B17) were then validated in an independent set of samples (50 GD patients and 50 matched healthy ones) by the Accucopy assay method. The CNV of the other 2 genes TRY6 and CCL3L1 was investigated in 144 GD patients and 144 healthy volunteers by the definitive genotyping technique using the Taqman quantitative polymerase-chain-reaction (Taqman qPCR). TRY6 gene-associated single nucleotide polymorphism (SNP), rs13230029, was genotyped by the PCR-ligase detection reaction (LDR) in 675 GD patients and 898 healthy controls. There were no correlation of the gene copy number (GCN) of CFH, CFHR1, KIAA0125, UGT2B15, and UGT2B17 with GD. In comparison with that of controls, the GCN distribution of TRY6 and CCL3L1 in GD patients did not show significantly differ (P > 0.05). Furthermore, TRY6-related polymorphism (rs13230029) showed no difference between GD patients and controls. No correlation was found between CNV or SNP genotype and clinical phenotypes. Generally, there were no link of the copy numbers of several genes, including CFH, CFHR1, KIAA0125, UGT2B15, UGT2B17, TRY6, and CCL3L1 to GD. Our results clearly indicated that the copy number variations of multiple genes, namely CFH, CFHR1, KIAA0125, UGT2B15, UGT2B17, TRY6, and CCL3L1, were not associated with the development of GD.

  8. Environmental change drives accelerated adaptation through stimulated copy number variation

    Science.gov (United States)

    Hull, Ryan M.; Cruz, Cristina; Jack, Carmen V.

    2017-01-01

    Copy number variation (CNV) is rife in eukaryotic genomes and has been implicated in many human disorders, particularly cancer, in which CNV promotes both tumorigenesis and chemotherapy resistance. CNVs are considered random mutations but often arise through replication defects; transcription can interfere with replication fork progression and stability, leading to increased mutation rates at highly transcribed loci. Here we investigate whether inducible promoters can stimulate CNV to yield reproducible, environment-specific genetic changes. We propose a general mechanism for environmentally-stimulated CNV and validate this mechanism for the emergence of copper resistance in budding yeast. By analysing a large cohort of individual cells, we directly demonstrate that CNV of the copper-resistance gene CUP1 is stimulated by environmental copper. CNV stimulation accelerates the formation of novel alleles conferring enhanced copper resistance, such that copper exposure actively drives adaptation to copper-rich environments. Furthermore, quantification of CNV in individual cells reveals remarkable allele selectivity in the rate at which specific environments stimulate CNV. We define the key mechanistic elements underlying this selectivity, demonstrating that CNV is regulated by both promoter activity and acetylation of histone H3 lysine 56 (H3K56ac) and that H3K56ac is required for CUP1 CNV and efficient copper adaptation. Stimulated CNV is not limited to high-copy CUP1 repeat arrays, as we find that H3K56ac also regulates CNV in 3 copy arrays of CUP1 or SFA1 genes. The impact of transcription on DNA damage is well understood, but our research reveals that this apparently problematic association forms a pathway by which mutations can be directed to particular loci in particular environments and furthermore that this mutagenic process can be regulated through histone acetylation. Stimulated CNV therefore represents an unanticipated and remarkably controllable pathway

  9. ALK Gene Copy Number Gain and Immunohistochemical Expression Status Using Three Antibodies in Neuroblastoma.

    Science.gov (United States)

    Kim, Eun Kyung; Kim, Sewha

    2017-01-01

    Anaplastic lymphoma kinase ( ALK) gene aberrations-such as mutations, amplifications, and copy number gains-represent a major genetic predisposition to neuroblastoma (NB). This study aimed to evaluate the correlation between ALK gene copy number status, ALK protein expression, and clinicopathological parameters. We retrospectively retrieved 30 cases of poorly differentiated NB and constructed tissue microarrays (TMAs). ALK copy number changes were assessed by fluorescence in situ hybridization (FISH) assays, and ALK immunohistochemistry (IHC) testing was performed using three different antibodies (ALK1, D5F3, and 5A4 clones). ALK amplification and copy number gain were observed in 10% (3/30) and 53.3% (16/30) of the cohort, respectively. There were positive correlations between ALK copy number and IHC-positive rate in ALK1 and 5A4 antibodies ( P copy number gain differed among the three antibodies, with 75% sensitivity in D5F3 and 0% sensitivity in ALK1. ALK-amplified NBs were correlated with synchronous MYCN amplification and chromosome 1p deletion. ALK IHC positivity was frequently observed in INSS stage IV and high-risk group patients. In conclusion, this study identified that an increase in the ALK copy number is a frequent genetic alteration in poorly differentiated NB. ALK-amplified NBs showed consistent ALK IHC positivity with all kinds of antibodies. In contrast, the detection performance of ALK copy number gain was antibody dependent, with the D5F3 antibody showing the best sensitivity.

  10. An open label phase II study evaluating first-line EGFR tyrosine kinase inhibitor erlotinib in non-small cell lung cancer patients with tumors showing high EGFR gene copy number

    Science.gov (United States)

    Kowalczyk, Anna; Suszko-Kazarnowicz, Malgorzata; Duchnowska, Renata; Szczesna, Aleksandra; Ratajska, Magdalena; Sowa, Aleksander; Limon, Janusz; Biernat, Wojciech; Burzykowski, Tomasz; Jassem, Jacek; Dziadziuszko, Rafal

    2017-01-01

    Background First-line treatment with epidermal growth factor receptor (EGFR) inhibitors in NSCLC is effective in patients with activating EGFR mutations. The activity of erlotinib in patients harboring high EGFR gene copy number has been considered debatable. Patients and Methods A multicenter, open-label, single-arm phase II clinical trial was performed to test the efficacy of erlotinib in the first-line treatment of NSCLC patients harboring high EGFR gene copy number defined as =4 copies in =40% of cells. Findings Between December 2007 and April 2011, tumor samples from 149 subjects were screened for EGFR gene copy number by fluorescence in-situ hybridization (FISH), Out of 49 patients with positive EGFR FISH test, 45 were treated with erlotinib. Median PFS in the intent-to-treat population was 3.3 months (95%CI: 1.83.9 months), and median overall survival was 7.9 months (95% CI: 5.112.6 months). Toxicity profile of erlotinib was consistent with its known safety profile. The trial was stopped prematurely at 63% of originally planned sample size due to accumulating evidence that EGFR gene copy number should not be used to select NSCLC patients to first-line therapy with EGFR TKI. Data on erlotinib efficacy according to EGFR, KRAS and BRAF mutations are additionally presented. Interpretation This trial argues against using high gene copy number for selection of NSCLC patients to first-line therapy with EGFR TKIs. The study adds to the discussion on efficacy of other targeted agents in patients with target gene amplified tumors. PMID:27924059

  11. Mitochondrial DNA Copy Number in Sleep Duration Discordant Monozygotic Twins

    DEFF Research Database (Denmark)

    Wrede, Joanna E; Mengel-From, Jonas; Buchwald, Dedra

    2015-01-01

    STUDY OBJECTIVES: Mitochondrial DNA (mtDNA) copy number is an important component of mitochondrial function and varies with age, disease, and environmental factors. We aimed to determine whether mtDNA copy number varies with habitual differences in sleep duration within pairs of monozygotic twins....... SETTING: Academic clinical research center. PARTICIPANTS: 15 sleep duration discordant monozygotic twin pairs (30 twins, 80% female; mean age 42.1 years [SD 15.0]). DESIGN: Sleep duration was phenotyped with wrist actigraphy. Each twin pair included a "normal" (7-9 h/24) and "short" (sleeping...... twin. Fasting peripheral blood leukocyte DNA was assessed for mtDNA copy number via the n-fold difference between qPCR measured mtDNA and nuclear DNA creating an mtDNA measure without absolute units. We used generalized estimating equation linear regression models accounting for the correlated data...

  12. Genetically complex epilepsies, copy number variants and syndrome constellations.

    Science.gov (United States)

    Mefford, Heather C; Mulley, John C

    2010-10-05

    Epilepsy is one of the most common neurological disorders, with a prevalence of 1% and lifetime incidence of 3%. There are numerous epilepsy syndromes, most of which are considered to be genetic epilepsies. Despite the discovery of more than 20 genes for epilepsy to date, much of the genetic contribution to epilepsy is not yet known. Copy number variants have been established as an important source of mutation in other complex brain disorders, including intellectual disability, autism and schizophrenia. Recent advances in technology now facilitate genome-wide searches for copy number variants and are beginning to be applied to epilepsy. Here, we discuss what is currently known about the contribution of copy number variants to epilepsy, and how that knowledge is redefining classification of clinical and genetic syndromes.

  13. Genome wide copy number analysis of single cells

    Science.gov (United States)

    Baslan, Timour; Kendall, Jude; Rodgers, Linda; Cox, Hilary; Riggs, Mike; Stepansky, Asya; Troge, Jennifer; Ravi, Kandasamy; Esposito, Diane; Lakshmi, B.; Wigler, Michael; Navin, Nicholas; Hicks, James

    2016-01-01

    Summary Copy number variation (CNV) is increasingly recognized as an important contributor to phenotypic variation in health and disease. Most methods for determining CNV rely on admixtures of cells, where information regarding genetic heterogeneity is lost. Here, we present a protocol that allows for the genome wide copy number analysis of single nuclei isolated from mixed populations of cells. Single nucleus sequencing (SNS), combines flow sorting of single nuclei based on DNA content, whole genome amplification (WGA), followed by next generation sequencing to quantize genomic intervals in a genome wide manner. Multiplexing of single cells is discussed. Additionally, we outline informatic approaches that correct for biases inherent in the WGA procedure and allow for accurate determination of copy number profiles. All together, the protocol takes ~3 days from flow cytometry to sequence-ready DNA libraries. PMID:22555242

  14. Copy-number variants in neurodevelopmental disorders: promises and challenges.

    LENUS (Irish Health Repository)

    Merikangas, Alison K

    2012-02-01

    Copy-number variation (CNV) is the most prevalent type of structural variation in the human genome. There is emerging evidence that copy-number variants (CNVs) provide a new vista on understanding susceptibility to neuropsychiatric disorders. Some challenges in the interpretation of current CNV studies include the use of overlapping samples, differing phenotypic definitions, an absence of population norms for CNVs and a lack of consensus in methods for CNV detection and analysis. Here, we review current CNV association study methods and results in autism spectrum disorders (ASD) and schizophrenia, and provide suggestions for design approaches to future studies that might maximize the translation of this work to etiological understanding.

  15. Chromosome copy number variation and control in the ciliate Chilodonella uncinata.

    Directory of Open Access Journals (Sweden)

    Kevin J Spring

    Full Text Available Copy number variations are widespread in eukaryotes. The unusual genome architecture of ciliates, in particular, with its process of amitosis in macronuclear division, provides a valuable model in which to study copy number variation. The current model of amitosis envisions stochastic distribution of macronuclear chromosomes during asexual reproduction. This suggests that amitosis is likely to result in high levels of copy number variation in ciliates, as dividing daughter cells can have variable copy numbers of chromosomes if chromosomal distribution during amitosis is a stochastic process. We examined chromosomal distribution during amitosis in Chilodonella uncinata, a ciliate with gene-size macronuclear chromosomes. We quantified 4 chromosomes in evolving populations of C. uncinata and modeled the amitotic distribution process. We found that macronuclear chromosomes differ in copy number from one another but that copy number does not change as expected under a stochastic process. The chromosome carrying SSU increased in copy number, which is consistent with selection to increase abundance; however, two other studied chromosomes displayed much lower than expected among-line variance. Our models suggest that balancing selection is sufficient to explain the observed maintenance of chromosome copy during asexual reproduction.

  16. Abundant copy-number loss of CYCLOPS and STOP genes in gastric adenocarcinoma.

    Science.gov (United States)

    Cutcutache, Ioana; Wu, Alice Yingting; Suzuki, Yuka; McPherson, John Richard; Lei, Zhengdeng; Deng, Niantao; Zhang, Shenli; Wong, Wai Keong; Soo, Khee Chee; Chan, Weng Hoong; Ooi, London Lucien; Welsch, Roy; Tan, Patrick; Rozen, Steven G

    2016-04-01

    Gastric cancer, a leading cause of cancer death worldwide, has been little studied compared with other cancers that impose similar health burdens. Our goal is to assess genomic copy-number loss and the possible functional consequences and therapeutic implications thereof across a large series of gastric adenocarcinomas. We used high-density single-nucleotide polymorphism microarrays to determine patterns of copy-number loss and allelic imbalance in 74 gastric adenocarcinomas. We investigated whether suppressor of tumorigenesis and/or proliferation (STOP) genes are associated with genomic copy-number loss. We also analyzed the extent to which copy-number loss affects Copy-number alterations Yielding Cancer Liabilities Owing to Partial losS (CYCLOPS) genes-genes that may be attractive targets for therapeutic inhibition when partially deleted. The proportion of the genome subject to copy-number loss varies considerably from tumor to tumor, with a median of 5.5 %, and a mean of 12 % (range 0-58.5 %). On average, 91 STOP genes were subject to copy-number loss per tumor (median 35, range 0-452), and STOP genes tended to have lower copy-number compared with the rest of the genes. Furthermore, on average, 1.6 CYCLOPS genes per tumor were both subject to copy-number loss and downregulated, and 51.4 % of the tumors had at least one such gene. The enrichment of STOP genes in regions of copy-number loss indicates that their deletion may contribute to gastric carcinogenesis. Furthermore, the presence of several deleted and downregulated CYCLOPS genes in some tumors suggests potential therapeutic targets in these tumors.

  17. An efficient method for measuring copy number variation applied to improvement of nematode resistance in soybean.

    Science.gov (United States)

    Lee, Tong Geon; Diers, Brian W; Hudson, Matthew E

    2016-10-01

    Copy number variation (CNV) is implicated in important traits in multiple crop plants, but can be challenging to genotype using conventional methods. The Rhg1 locus of soybean, which confers resistance to soybean cyst nematode (SCN), is a CNV of multiple 31.2-kb genomic units each containing four genes. Reliable, high-throughput methods to quantify Rhg1 and other CNVs for selective breeding were developed. The CNV genotyping assay described here uses a homeologous gene copy within the paleopolyploid soybean genome to provide the internal control for a single-tube TaqMan copy number assay. Using this assay, CNV in breeding populations can be tracked with high precision. We also show that extensive CNV exists within Fayette, a released, inbred SCN-resistant soybean cultivar with a high copy number at Rhg1 derived from a single donor parent. Copy number at Rhg1 is therefore unstable within a released variety over a relatively small number of generations. Using this assay to select for individuals with altered copy number, plants were obtained with both increased copy number and increased SCN resistance relative to control plants. Thus, CNV genotyping technologies can be used as a new type of marker-assisted selection to select for desirable traits in breeding populations, and to control for undesirable variation within cultivars. © 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.

  18. Identifying Potential Regions of Copy Number Variation for Bipolar Disorder

    Directory of Open Access Journals (Sweden)

    Yi-Hsuan Chen

    2014-02-01

    Full Text Available Bipolar disorder is a complex psychiatric disorder with high heritability, but its genetic determinants are still largely unknown. Copy number variation (CNV is one of the sources to explain part of the heritability. However, it is a challenge to estimate discrete values of the copy numbers using continuous signals calling from a set of markers, and to simultaneously perform association testing between CNVs and phenotypic outcomes. The goal of the present study is to perform a series of data filtering and analysis procedures using a DNA pooling strategy to identify potential CNV regions that are related to bipolar disorder. A total of 200 normal controls and 200 clinically diagnosed bipolar patients were recruited in this study, and were randomly divided into eight control and eight case pools. Genome-wide genotyping was employed using Illumina Human Omni1-Quad array with approximately one million markers for CNV calling. We aimed at setting a series of criteria to filter out the signal noise of marker data and to reduce the chance of false-positive findings for CNV regions. We first defined CNV regions for each pool. Potential CNV regions were reported based on the different patterns of CNV status between cases and controls. Genes that were mapped into the potential CNV regions were examined with association testing, Gene Ontology enrichment analysis, and checked with existing literature for their associations with bipolar disorder. We reported several CNV regions that are related to bipolar disorder. Two CNV regions on chromosome 11 and 22 showed significant signal differences between cases and controls (p < 0.05. Another five CNV regions on chromosome 6, 9, and 19 were overlapped with results in previous CNV studies. Experimental validation of two CNV regions lent some support to our reported findings. Further experimental and replication studies could be designed for these selected regions.

  19. Peripheral blood mitochondrial DNA copy number is associated with prostate cancer risk and tumor burden.

    Directory of Open Access Journals (Sweden)

    Weimin Zhou

    Full Text Available Alterations of mitochondrial DNA (mtDNA have been associated with the risk of a number of human cancers; however, the relationship between mtDNA copy number in peripheral blood leukocytes (PBLs and the risk of prostate cancer (PCa has not been investigated. In a case-control study of 196 PCa patients and 196 age-paired healthy controls in a Chinese Han population, the association between mtDNA copy number in PBLs and PCa risk was evaluated. The relative mtDNA copy number was measured using quantitative real-time PCR; samples from three cases and two controls could not be assayed, leaving 193 cases and 194 controls for analysis. PCa patients had significantly higher mtDNA copy numbers than controls (medians 0.91 and 0.82, respectively; P<0.001. Dichotomized at the median value of mtDNA copy number in the controls, high mtDNA copy number was significantly associated with an increased risk of PCa (adjusted odds ratio= 1.85, 95% confidence interval: 1.21-2.83. A significant dose-response relationship was observed between mtDNA copy number and risk of PCa in quartile analysis (Ptrend = 0.011. Clinicopathological analysis showed that high mtDNA copy numbers in PCa patients were significantly associated with high Gleason score and advanced tumor stage, but not serum prostate-specific antigen level (P = 0.002, 0.012 and 0.544, respectively. These findings of the present study indicate that increased mtDNA copy number in PBLs is significantly associated with an increased risk of PCa and may be a reflection of tumor burden.

  20. Genomic Copy Number Variation in Disorders of Cognitive Development

    Science.gov (United States)

    Morrow, Eric M.

    2010-01-01

    Objective: To highlight recent discoveries in the area of genomic copy number variation in neuropsychiatric disorders including intellectual disability, autism, and schizophrenia. To emphasize new principles emerging from this area, involving the genetic architecture of disease, pathophysiology, and diagnosis. Method: Review of studies published…

  1. Copy number variations in affective disorders and meta-analysis

    DEFF Research Database (Denmark)

    Olsen, Line; Hansen, Thomas; Djurovic, Srdjan

    2011-01-01

    In two recent studies 10 copy number variants (CNV) were found to be overrepresented either among patients suffering from affective disorders in an Amish family or in the Wellcome Trust Case-Control Consortium study. Here, we investigate if these variants are associated with affective disorders...

  2. Bovine copy number variation and its implication in animal health

    Science.gov (United States)

    Recently it has become apparent that previously unappreciated genomic structural variation, including copy number variations (CNV), contributes significantly to individual health and disease in humans and rodents. As a complement to the bovine HapMap project, we initiated a systematic study of the C...

  3. Haplotyping and copy number estimation of the highly polymorphic human beta-defensin locus on 8p23 by 454 amplicon sequencing

    Directory of Open Access Journals (Sweden)

    Rosenstiel Philip

    2010-04-01

    Full Text Available Abstract Background The beta-defensin gene cluster (DEFB at chromosome 8p23.1 is one of the most copy number (CN variable regions of the human genome. Whereas individual DEFB CNs have been suggested as independent genetic risk factors for several diseases (e.g. psoriasis and Crohn's disease, the role of multisite sequence variations (MSV is less well understood and to date has only been reported for prostate cancer. Simultaneous assessment of MSVs and CNs can be achieved by PCR, cloning and Sanger sequencing, however, these methods are labour and cost intensive as well as prone to methodological bias introduced by bacterial cloning. Here, we demonstrate that amplicon sequencing of pooled individual PCR products by the 454 technology allows in-depth determination of MSV haplotypes and estimation of DEFB CNs in parallel. Results Six PCR products spread over ~87 kb of DEFB and harbouring 24 known MSVs were amplified from 11 DNA samples, pooled and sequenced on a Roche 454 GS FLX sequencer. From ~142,000 reads, ~120,000 haplotype calls (HC were inferred that identified 22 haplotypes ranging from 2 to 7 per amplicon. In addition to the 24 known MSVs, two additional sequence variations were detected. Minimal CNs were estimated from the ratio of HCs and compared to absolute CNs determined by alternative methods. Concordance in CNs was found for 7 samples, the CNs differed by one in 2 samples and the estimated minimal CN was half of the absolute in one sample. For 7 samples and 2 amplicons, the 454 haplotyping results were compared to those by cloning/Sanger sequencing. Intrinsic problems related to chimera formation during PCR and differences between haplotyping by 454 and cloning/Sanger sequencing are discussed. Conclusion Deep amplicon sequencing using the 454 technology yield thousands of HCs per amplicon for an affordable price and may represent an effective method for parallel haplotyping and CN estimation in small to medium-sized cohorts. The

  4. DUF1220-domain copy number implicated in human brain-size pathology and evolution

    National Research Council Canada - National Science Library

    Dumas, Laura J; O'Bleness, Majesta S; Davis, Jonathan M; Dickens, C Michael; Anderson, Nathan; Keeney, J G; Jackson, Jay; Sikela, Megan; Raznahan, Armin; Giedd, Jay; Rapoport, Judith; Nagamani, Sandesh S C; Erez, Ayelet; Brunetti-Pierri, Nicola; Sugalski, Rachel; Lupski, James R; Fingerlin, Tasha; Cheung, Sau Wai; Sikela, James M

    2012-01-01

    ... have been associated with microcephaly and macrocephaly, respectively. Given these findings and the high correlation between DUF1220 copy number and brain size across primate lineages (R(2) = 0.98; p = 1.8 × 10(-6...

  5. Quantum state discrimination using the minimum average number of copies

    CERN Document Server

    Slussarenko, Sergei; Li, Jun-Gang; Campbell, Nicholas; Wiseman, Howard M; Pryde, Geoff J

    2016-01-01

    In the task of discriminating between nonorthogonal quantum states from multiple copies, the key parameters are the error probability and the resources (number of copies) used. Previous studies have considered the task of minimizing the average error probability for fixed resources. Here we consider minimizing the average resources for a fixed admissible error probability. We derive a detection scheme optimized for the latter task, and experimentally test it, along with schemes previously considered for the former task. We show that, for our new task, our new scheme outperforms all previously considered schemes.

  6. Copy-number changes in evolution: rates, fitness effects and adaptive significance

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    Vaishali eKatju

    2013-12-01

    Full Text Available Gene copy-number differences due to gene duplications and deletions are rampant in natural populations and play a crucial role in the evolution of genome complexity. Per-locus analyses of gene duplication rates in the pre-genomic era revealed that gene duplication rates are much higher than the per nucleotide substitution rate. Analyses of gene duplication and deletion rates in mutation accumulation lines of model organisms have revealed that these high rates of copy-number mutations occur at a genome-wide scale. Furthermore, comparisons of the spontaneous duplication and deletion rates to copy-number polymorphism data and bioinformatic-based estimates of duplication rates from sequenced genomes suggest that the vast majority of gene duplications are detrimental and removed by natural selection. The rate at which new gene copies appear in populations greatly influences their evolutionary dynamics and standing gene copy-number variation in populations. The opportunity for mutations that result in the maintenance of duplicate copies, either through neofunctionalization or subfunctionalization, also depends on the equilibrium frequency of additional gene copies in the population, and hence on the spontaneous gene duplication (and loss rate. The duplication rate may therefore have profound effects on the role of adaptation in the evolution of duplicated genes as well as important consequences for the evolutionary potential of organisms. We further discuss the broad ramifications of this standing gene copy-number variation on fitness and adaptive potential from a population-genetic and genome-wide perspective.

  7. A multilevel model to address batch effects in copy number estimation using SNP arrays.

    Science.gov (United States)

    Scharpf, Robert B; Ruczinski, Ingo; Carvalho, Benilton; Doan, Betty; Chakravarti, Aravinda; Irizarry, Rafael A

    2011-01-01

    Submicroscopic changes in chromosomal DNA copy number dosage are common and have been implicated in many heritable diseases and cancers. Recent high-throughput technologies have a resolution that permits the detection of segmental changes in DNA copy number that span thousands of base pairs in the genome. Genomewide association studies (GWAS) may simultaneously screen for copy number phenotype and single nucleotide polymorphism (SNP) phenotype associations as part of the analytic strategy. However, genomewide array analyses are particularly susceptible to batch effects as the logistics of preparing DNA and processing thousands of arrays often involves multiple laboratories and technicians, or changes over calendar time to the reagents and laboratory equipment. Failure to adjust for batch effects can lead to incorrect inference and requires inefficient post hoc quality control procedures to exclude regions that are associated with batch. Our work extends previous model-based approaches for copy number estimation by explicitly modeling batch and using shrinkage to improve locus-specific estimates of copy number uncertainty. Key features of this approach include the use of biallelic genotype calls from experimental data to estimate batch-specific and locus-specific parameters of background and signal without the requirement of training data. We illustrate these ideas using a study of bipolar disease and a study of chromosome 21 trisomy. The former has batch effects that dominate much of the observed variation in the quantile-normalized intensities, while the latter illustrates the robustness of our approach to a data set in which approximately 27% of the samples have altered copy number. Locus-specific estimates of copy number can be plotted on the copy number scale to investigate mosaicism and guide the choice of appropriate downstream approaches for smoothing the copy number as a function of physical position. The software is open source and implemented in the R

  8. Copy number variations and cognitive phenotypes in unselected populations.

    Science.gov (United States)

    Männik, Katrin; Mägi, Reedik; Macé, Aurélien; Cole, Ben; Guyatt, Anna L; Shihab, Hashem A; Maillard, Anne M; Alavere, Helene; Kolk, Anneli; Reigo, Anu; Mihailov, Evelin; Leitsalu, Liis; Ferreira, Anne-Maud; Nõukas, Margit; Teumer, Alexander; Salvi, Erika; Cusi, Daniele; McGue, Matt; Iacono, William G; Gaunt, Tom R; Beckmann, Jacques S; Jacquemont, Sébastien; Kutalik, Zoltán; Pankratz, Nathan; Timpson, Nicholas; Metspalu, Andres; Reymond, Alexandre

    2015-05-26

    The association of copy number variations (CNVs), differing numbers of copies of genetic sequence at locations in the genome, with phenotypes such as intellectual disability has been almost exclusively evaluated using clinically ascertained cohorts. The contribution of these genetic variants to cognitive phenotypes in the general population remains unclear. To investigate the clinical features conferred by CNVs associated with known syndromes in adult carriers without clinical preselection and to assess the genome-wide consequences of rare CNVs (frequency ≤0.05%; size ≥250 kilobase pairs [kb]) on carriers' educational attainment and intellectual disability prevalence in the general population. The population biobank of Estonia contains 52,000 participants enrolled from 2002 through 2010. General practitioners examined participants and filled out a questionnaire of health- and lifestyle-related questions, as well as reported diagnoses. Copy number variant analysis was conducted on a random sample of 7877 individuals and genotype-phenotype associations with education and disease traits were evaluated. Our results were replicated on a high-functioning group of 993 Estonians and 3 geographically distinct populations in the United Kingdom, the United States, and Italy. Phenotypes of genomic disorders in the general population, prevalence of autosomal CNVs, and association of these variants with educational attainment (from less than primary school through scientific degree) and prevalence of intellectual disability. Of the 7877 in the Estonian cohort, we identified 56 carriers of CNVs associated with known syndromes. Their phenotypes, including cognitive and psychiatric problems, epilepsy, neuropathies, obesity, and congenital malformations are similar to those described for carriers of identical rearrangements ascertained in clinical cohorts. A genome-wide evaluation of rare autosomal CNVs (frequency, ≤0.05%; ≥250 kb) identified 831 carriers (10.5%) of the

  9. CCL3L1 copy number, HIV load, and immune reconstitution in sub-Saharan Africans

    Science.gov (United States)

    2013-01-01

    Background The role of copy number variation of the CCL3L1 gene, encoding MIP1α, in contributing to the host variation in susceptibility and response to HIV infection is controversial. Here we analyse a sub-Saharan African cohort from Tanzania and Ethiopia, two countries with a high prevalence of HIV-1 and a high co-morbidity of HIV with tuberculosis. Methods We use a form of quantitative PCR called the paralogue ratio test to determine CCL3L1 gene copy number in 1134 individuals and validate our copy number typing using array comparative genomic hybridisation and fiber-FISH. Results We find no significant association of CCL3L1 gene copy number with HIV load in antiretroviral-naïve patients prior to initiation of combination highly active anti-retroviral therapy. However, we find a significant association of low CCL3L1 gene copy number with improved immune reconstitution following initiation of highly active anti-retroviral therapy (p = 0.012), replicating a previous study. Conclusions Our work supports a role for CCL3L1 copy number in immune reconstitution following antiretroviral therapy in HIV, and suggests that the MIP1α -CCR5 axis might be targeted to aid immune reconstitution. PMID:24219137

  10. Low AMY1 Gene Copy Number Is Associated with Increased Body Mass Index in Prepubertal Boys.

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    M Loredana Marcovecchio

    Full Text Available Genome-wide association studies have identified more than 60 single nucleotide polymorphisms associated with Body Mass Index (BMI. Additional genetic variants, such as copy number variations (CNV, have also been investigated in relation to BMI. Recently, the highly polymorphic CNV in the salivary amylase (AMY1 gene, encoding an enzyme implicated in the first step of starch digestion, has been associated with obesity in adults and children. We assessed the potential association between AMY1 copy number and a wide range of BMI in a population of Italian school-children.744 children (354 boys, 390 girls, mean age (±SD: 8.4±1.4years underwent anthropometric assessments (height, weight and collection of saliva samples for DNA extraction. AMY1 copies were evaluated by quantitative PCR.A significant increase of BMI z-score by decreasing AMY1 copy number was observed in boys (β: -0.117, p = 0.033, but not in girls. Similarly, waist circumference (β: -0.155, p = 0.003, adjusted for age was negatively influenced by AMY1 copy number in boys. Boys with 8 or more AMY1 copy numbers presented a significant lower BMI z-score (p = 0.04 and waist circumference (p = 0.01 when compared to boys with less than 8 copy numbers.In this pediatric-only, population-based study, a lower AMY1 copy number emerged to be associated with increased BMI in boys. These data confirm previous findings from adult studies and support a potential role of a higher copy number of the salivary AMY1 gene in protecting from excess weight gain.

  11. Low AMY1 Gene Copy Number Is Associated with Increased Body Mass Index in Prepubertal Boys

    Science.gov (United States)

    Verginelli, Fabio; De Lellis, Laura; Capelli, Cristian; Verzilli, Delfina; Chiarelli, Francesco; Mohn, Angelika; Cama, Alessandro

    2016-01-01

    Background Genome-wide association studies have identified more than 60 single nucleotide polymorphisms associated with Body Mass Index (BMI). Additional genetic variants, such as copy number variations (CNV), have also been investigated in relation to BMI. Recently, the highly polymorphic CNV in the salivary amylase (AMY1) gene, encoding an enzyme implicated in the first step of starch digestion, has been associated with obesity in adults and children. We assessed the potential association between AMY1 copy number and a wide range of BMI in a population of Italian school-children. Methods 744 children (354 boys, 390 girls, mean age (±SD): 8.4±1.4years) underwent anthropometric assessments (height, weight) and collection of saliva samples for DNA extraction. AMY1 copies were evaluated by quantitative PCR. Results A significant increase of BMI z-score by decreasing AMY1 copy number was observed in boys (β: -0.117, p = 0.033), but not in girls. Similarly, waist circumference (β: -0.155, p = 0.003, adjusted for age) was negatively influenced by AMY1 copy number in boys. Boys with 8 or more AMY1 copy numbers presented a significant lower BMI z-score (p = 0.04) and waist circumference (p = 0.01) when compared to boys with less than 8 copy numbers. Conclusions In this pediatric-only, population-based study, a lower AMY1 copy number emerged to be associated with increased BMI in boys. These data confirm previous findings from adult studies and support a potential role of a higher copy number of the salivary AMY1 gene in protecting from excess weight gain. PMID:27149670

  12. A Method for Calling Copy Number Polymorphism Using Haplotypes

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    Gun Ho eJang

    2013-09-01

    Full Text Available Single nucleotide polymorphism (SNP and copy number variation (CNV are both widespread characteristic of the human genome, but are often called separately on common genotyping platforms. To capture integrated SNP and CNV information, methods have been developed for calling allelic specific copy numbers or so called copy number polymorphism (CNP, using limited inter-marker correlation. In this paper, we proposed a haplotype-based maximum likelihood method to call CNP, which takes advantage of the valuable multi-locus linkage disequilibrium (LD information in the population. We also developed a computationally efficient EM algorithm to estimate haplotype frequencies and optimize individual CNP calls simultaneously, even at presence of missing data. Through simulations, we demonstrated our model is more sensitive and accurate in detecting various CNV regions, compared with commonly-used CNV calling methods including PennCNV, another hidden Markov model using CNP, a scan statistic, segCNV, and cnvHap. Our method often performs better in the regions with higher LD, in longer CNV regions, and in common CNV than the opposite. We implemented our method on the genotypes of 90 HapMap CEU samples and 23 patients with acute lung injury (ALI. For each ALI patient the genotyping was performed twice. The CNPs from our method show good consistency and accuracy comparable to others.

  13. Determining frequent patterns of copy number alterations in cancer.

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    Franck Rapaport

    Full Text Available Cancer progression is often driven by an accumulation of genetic changes but also accompanied by increasing genomic instability. These processes lead to a complicated landscape of copy number alterations (CNAs within individual tumors and great diversity across tumor samples. High resolution array-based comparative genomic hybridization (aCGH is being used to profile CNAs of ever larger tumor collections, and better computational methods for processing these data sets and identifying potential driver CNAs are needed. Typical studies of aCGH data sets take a pipeline approach, starting with segmentation of profiles, calls of gains and losses, and finally determination of frequent CNAs across samples. A drawback of pipelines is that choices at each step may produce different results, and biases are propagated forward. We present a mathematically robust new method that exploits probe-level correlations in aCGH data to discover subsets of samples that display common CNAs. Our algorithm is related to recent work on maximum-margin clustering. It does not require pre-segmentation of the data and also provides grouping of recurrent CNAs into clusters. We tested our approach on a large cohort of glioblastoma aCGH samples from The Cancer Genome Atlas and recovered almost all CNAs reported in the initial study. We also found additional significant CNAs missed by the original analysis but supported by earlier studies, and we identified significant correlations between CNAs.

  14. Identification of candidate growth promoting genes in ovarian cancer through integrated copy number and expression analysis.

    Science.gov (United States)

    Ramakrishna, Manasa; Williams, Louise H; Boyle, Samantha E; Bearfoot, Jennifer L; Sridhar, Anita; Speed, Terence P; Gorringe, Kylie L; Campbell, Ian G

    2010-04-08

    Ovarian cancer is a disease characterised by complex genomic rearrangements but the majority of the genes that are the target of these alterations remain unidentified. Cataloguing these target genes will provide useful insights into the disease etiology and may provide an opportunity to develop novel diagnostic and therapeutic interventions. High resolution genome wide copy number and matching expression data from 68 primary epithelial ovarian carcinomas of various histotypes was integrated to identify genes in regions of most frequent amplification with the strongest correlation with expression and copy number. Regions on chromosomes 3, 7, 8, and 20 were most frequently increased in copy number (> 40% of samples). Within these regions, 703/1370 (51%) unique gene expression probesets were differentially expressed when samples with gain were compared to samples without gain. 30% of these differentially expressed probesets also showed a strong positive correlation (r > or =0.6) between expression and copy number. We also identified 21 regions of high amplitude copy number gain, in which 32 known protein coding genes showed a strong positive correlation between expression and copy number. Overall, our data validates previously known ovarian cancer genes, such as ERBB2, and also identified novel potential drivers such as MYNN, PUF60 and TPX2.

  15. Identification of candidate growth promoting genes in ovarian cancer through integrated copy number and expression analysis.

    Directory of Open Access Journals (Sweden)

    Manasa Ramakrishna

    Full Text Available Ovarian cancer is a disease characterised by complex genomic rearrangements but the majority of the genes that are the target of these alterations remain unidentified. Cataloguing these target genes will provide useful insights into the disease etiology and may provide an opportunity to develop novel diagnostic and therapeutic interventions. High resolution genome wide copy number and matching expression data from 68 primary epithelial ovarian carcinomas of various histotypes was integrated to identify genes in regions of most frequent amplification with the strongest correlation with expression and copy number. Regions on chromosomes 3, 7, 8, and 20 were most frequently increased in copy number (> 40% of samples. Within these regions, 703/1370 (51% unique gene expression probesets were differentially expressed when samples with gain were compared to samples without gain. 30% of these differentially expressed probesets also showed a strong positive correlation (r > or =0.6 between expression and copy number. We also identified 21 regions of high amplitude copy number gain, in which 32 known protein coding genes showed a strong positive correlation between expression and copy number. Overall, our data validates previously known ovarian cancer genes, such as ERBB2, and also identified novel potential drivers such as MYNN, PUF60 and TPX2.

  16. Estimating Copy Number and Allelic Variation at the Immunoglobulin Heavy Chain Locus Using Short Reads.

    Directory of Open Access Journals (Sweden)

    Shishi Luo

    2016-09-01

    Full Text Available The study of genomic regions that contain gene copies and structural variation is a major challenge in modern genomics. Unlike variation involving single nucleotide changes, data on the variation of copy number is difficult to collect and few tools exist for analyzing the variation between individuals. The immunoglobulin heavy variable (IGHV locus, which plays an integral role in the adaptive immune response, is an example of a complex genomic region that varies in gene copy number. Lack of standard methods to genotype this region prevents it from being included in association studies and is holding back the growing field of antibody repertoire analysis. Here we develop a method that takes short reads from high-throughput sequencing and outputs a genetic profile of the IGHV locus with the read coverage depth and a putative nucleotide sequence for each operationally defined gene cluster. Our operationally defined gene clusters aim to address a major challenge in studying the IGHV locus: the high sequence similarity between gene segments in different genomic locations. Tests on simulated data demonstrate that our approach can accurately determine the presence or absence of a gene cluster from reads as short as 70 bp. More detailed resolution on the copy number of gene clusters can be obtained from read coverage depth using longer reads (e.g., ≥ 100 bp. Detail at the nucleotide resolution of single copy genes (genes present in one copy per haplotype can be determined with 250 bp reads. For IGHV genes with more than one copy, accurate nucleotide-resolution reconstruction is currently beyond the means of our approach. When applied to a family of European ancestry, our pipeline outputs genotypes that are consistent with the family pedigree, confirms existing multigene variants and suggests new copy number variants. This study paves the way for analyzing population-level patterns of variation in IGHV gene clusters in larger diverse datasets and for

  17. Copy number variation of KIR genes influences HIV-1 control

    DEFF Research Database (Denmark)

    Pelak, Kimberly; Need, Anna C; Fellay, Jacques

    2011-01-01

    A genome-wide screen for large structural variants showed that a copy number variant (CNV) in the region encoding killer cell immunoglobulin-like receptors (KIR) associates with HIV-1 control as measured by plasma viral load at set point in individuals of European ancestry. This CNV encompasses...... the KIR3DL1-KIR3DS1 locus, encoding receptors that interact with specific HLA-Bw4 molecules to regulate the activation of lymphocyte subsets including natural killer (NK) cells. We quantified the number of copies of KIR3DS1 and KIR3DL1 in a large HIV-1 positive cohort, and showed that an increase in KIR3...... individuals with multiple copies of KIR3DL1, in the presence of KIR3DS1 and the appropriate ligands, inhibit HIV-1 replication more robustly, and associated with a significant expansion in the frequency of KIR3DS1+, but not KIR3DL1+, NK cells in their peripheral blood. Our results suggest that the relative...

  18. Effective Normalization for Copy Number Variation Detection from Whole Genome Sequencing

    NARCIS (Netherlands)

    Janevski, A.; Varadan, V.; Kamalakaran, S.; Banerjee, N.; Dimitrova, D.

    2012-01-01

    Background Whole genome sequencing enables a high resolution view ofthe human genome and provides unique insights into genome structureat an unprecedented scale. There have been a number of tools to infer copy number variation in the genome. These tools while validatedalso include a number of parame

  19. Potential Value of Genomic Copy Number Variations in Schizophrenia

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    Chuanjun Zhuo

    2017-06-01

    Full Text Available Schizophrenia is a devastating neuropsychiatric disorder affecting approximately 1% of the global population, and the disease has imposed a considerable burden on families and society. Although, the exact cause of schizophrenia remains unknown, several lines of scientific evidence have revealed that genetic variants are strongly correlated with the development and early onset of the disease. In fact, the heritability among patients suffering from schizophrenia is as high as 80%. Genomic copy number variations (CNVs are one of the main forms of genomic variations, ubiquitously occurring in the human genome. An increasing number of studies have shown that CNVs account for population diversity and genetically related diseases, including schizophrenia. The last decade has witnessed rapid advances in the development of novel genomic technologies, which have led to the identification of schizophrenia-associated CNVs, insight into the roles of the affected genes in their intervals in schizophrenia, and successful manipulation of the target CNVs. In this review, we focus on the recent discoveries of important CNVs that are associated with schizophrenia and outline the potential values that the study of CNVs will bring to the areas of schizophrenia research, diagnosis, and therapy. Furthermore, with the help of the novel genetic tool known as the Clustered Regularly Interspaced Short Palindromic Repeats-associated nuclease 9 (CRISPR/Cas9 system, the pathogenic CNVs as genomic defects could be corrected. In conclusion, the recent novel findings of schizophrenia-associated CNVs offer an exciting opportunity for schizophrenia research to decipher the pathological mechanisms underlying the onset and development of schizophrenia as well as to provide potential clinical applications in genetic counseling, diagnosis, and therapy for this complex mental disease.

  20. The Klinefelter syndrome is associated with high recurrence of copy number variations on the X chromosome with a potential role in the clinical phenotype.

    Science.gov (United States)

    Rocca, M S; Pecile, V; Cleva, L; Speltra, E; Selice, R; Di Mambro, A; Foresta, C; Ferlin, A

    2016-03-01

    The Klinefelter syndrome (KS) is the most frequent sex chromosomal disorder in males, characterized by at least one supernumerary X chromosome (most frequent karyotype 47,XXY). This syndrome presents with a broad range of phenotypes. The common characteristics include small testes and infertility, but KS subjects are at increased risk of hypogonadism, cognitive dysfunction, obesity, diabetes, metabolic syndrome, osteoporosis, and autoimmune disorders, which are present in variable proportion. Although part of the clinical variability might be linked to a different degree of testicular function observed in KS patients, genetic mechanisms of the supernumerary X chromosome might contribute. Gene-dosage effects and parental origin of the supernumerary X chromosome have been suggested to this regard. No study has been performed analyzing the genetic constitution of the X chromosome in terms of copy number variations (CNVs) and their possible involvement in phenotype of KS. To this aim, we performed a SNP arrays analysis on 94 KS and 85 controls. We found that KS subjects have more frequently than controls X-linked CNVs (39/94, [41.5%] with respect to 12/42, [28.6%] of females, and 8/43, [18.6%] of males, p < 0.01). The number of X-linked CNVs in KS patients was 4.58 ± 1.92 CNVs/subject, significantly higher with respect to that found in control females (1.50 ± 1.29 CNVs/subject) and males (1.14 ± 0.37 CNVs/subject). Importantly, 94.4% X-linked CNVs in KS subjects were duplications, higher with respect to control males (50.0%, p < 0.001) and females (83.3%, p = 0.1). Half of the X-linked CNVs fell within regions encompassing genes and most of them (90%) included genes escaping X-inactivation in the regions of X-Y homology, particularly in the pseudoautosomal region 1 (PAR1) and Xq21.31. This study described for the first time the genetic properties of the X chromosome in KS and suggests that X-linked CNVs (especially duplications) might contribute to the clinical

  1. An integrated Bayesian analysis of LOH and copy number data

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    Hutter Marcus

    2010-06-01

    Full Text Available Abstract Background Cancer and other disorders are due to genomic lesions. SNP-microarrays are able to measure simultaneously both genotype and copy number (CN at several Single Nucleotide Polymorphisms (SNPs along the genome. CN is defined as the number of DNA copies, and the normal is two, since we have two copies of each chromosome. The genotype of a SNP is the status given by the nucleotides (alleles which are present on the two copies of DNA. It is defined homozygous or heterozygous if the two alleles are the same or if they differ, respectively. Loss of heterozygosity (LOH is the loss of the heterozygous status due to genomic events. Combining CN and LOH data, it is possible to better identify different types of genomic aberrations. For example, a long sequence of homozygous SNPs might be caused by either the physical loss of one copy or a uniparental disomy event (UPD, i.e. each SNP has two identical nucleotides both derived from only one parent. In this situation, the knowledge of the CN can help in distinguishing between these two events. Results To better identify genomic aberrations, we propose a method (called gBPCR which infers the type of aberration occurred, taking into account all the possible influence in the microarray detection of the homozygosity status of the SNPs, resulting from an altered CN level. Namely, we model the distributions of the detected genotype, given a specific genomic alteration and we estimate the parameters involved on public reference datasets. The estimation is performed similarly to the modified Bayesian Piecewise Constant Regression, but with improved estimators for the detection of the breakpoints. Using artificial and real data, we evaluate the quality of the estimation of gBPCR and we also show that it outperforms other well-known methods for LOH estimation. Conclusions We propose a method (gBPCR for the estimation of both LOH and CN aberrations, improving their estimation by integrating both types

  2. The relationship between mitochondrial DNA copy number and stallion sperm function.

    Science.gov (United States)

    Darr, Christa R; Moraes, Luis E; Connon, Richard E; Love, Charles C; Teague, Sheila; Varner, Dickson D; Meyers, Stuart A

    2017-05-01

    Mitochondrial DNA (mtDNA) copy number has been utilized as a measure of sperm quality in several species including mice, dogs, and humans, and has been suggested as a potential biomarker of fertility in stallion sperm. The results of the present study extend this recent discovery using sperm samples from American Quarter Horse stallions of varying age. By determining copy number of three mitochondrial genes, cytochrome b (CYTB), NADH dehydrogenase 1 (ND1) and NADH dehydrogenase 4 (ND4), instead of a single gene, we demonstrate an improved understanding of mtDNA fate in stallion sperm mitochondria following spermatogenesis. Sperm samples from 37 stallions ranging from 3 to 24 years old were collected at four breeding ranches in north and central Texas during the 2015 breeding season. Samples were analyzed for sperm motion characteristics, nuclear DNA denaturability and mtDNA copy number. Mitochondrial DNA content in individual sperm was determined by real-time qPCR and normalized with a single copy nuclear gene, Beta actin. Exploratory correlation analysis revealed that total motility was negatively correlated with CYTB copy number and sperm chromatin structure. Stallion age did not have a significant effect on copy number for any of the genes. Copy number differences existed between the three genes with CYTB having the greatest number of copies (20.6 ± 1.2 copies, range: 6.0 to 41.1) followed by ND4 (15.5 ± 0.8 copies, range: 6.7 to 27.8) and finally ND1 (12.0 ± 1.0 copies, range: 0.4 to 26.6) (P copy number across mitochondrial genes is likely to be a result of mtDNA fragmentation and degradation since downregulation of sperm mtDNA occurs during spermatogenesis and may be important for normal sperm function. Beta regression analysis suggested that for every unit increase in mtDNA copy number of CYTB, there was a 4% decrease in the odds of sperm movement (P = 0.001). Influential analysis suggested that results are robust and not highly influenced by

  3. Copy number variation plays an important role in clinical epilepsy

    Science.gov (United States)

    Olson, Heather; Shen, Yiping; Avallone, Jennifer; Sheidley, Beth R.; Pinsky, Rebecca; Bergin, Ann M.; Berry, Gerard T.; Duffy, Frank H.; Eksioglu, Yaman; Harris, David J.; Hisama, Fuki M.; Ho, Eugenia; Irons, Mira; Jacobsen, Christina M.; James, Philip; Kothare, Sanjeev; Khwaja, Omar; Lipton, Jonathan; Loddenkemper, Tobias; Markowitz, Jennifer; Maski, Kiran; Megerian, J. Thomas; Neilan, Edward; Raffalli, Peter C.; Robbins, Michael; Roberts, Amy; Roe, Eugene; Rollins, Caitlin; Sahin, Mustafa; Sarco, Dean; Schonwald, Alison; Smith, Sharon E.; Soul, Janet; Stoler, Joan M.; Takeoka, Masanori; Tan, Wen-Han; Torres, Alcy R.; Tsai, Peter; Urion, David K.; Weissman, Laura; Wolff, Robert; Wu, Bai-Lin; Miller, David T.; Poduri, Annapurna

    2015-01-01

    Objective To evaluate the role of copy number abnormalities detectable by chromosomal microarray (CMA) testing in patients with epilepsy at a tertiary care center. Methods We identified patients with ICD-9 codes for epilepsy or seizures and clinical CMA testing performed between October 2006 and February 2011 at Boston Children’s Hospital. We reviewed medical records and included patients meeting criteria for epilepsy. We phenotypically characterized patients with epilepsy-associated abnormalities on CMA. Results Of 973 patients who had CMA and ICD-9 codes for epilepsy or seizures, 805 patients satisfied criteria for epilepsy. We observed 437 copy number variants (CNVs) in 323 patients (1–4 per patient), including 185 (42%) deletions and 252 (58%) duplications. Forty (9%) were confirmed de novo, 186 (43%) were inherited, and parental data were unavailable for 211 (48%). Excluding full chromosome trisomies, CNV size ranged from 18 kb to 142 Mb, and 34% were over 500 kb. In at least 40 cases (5%), the epilepsy phenotype was explained by a CNV, including 29 patients with epilepsy-associated syndromes and 11 with likely disease-associated CNVs involving epilepsy genes or “hotspots.” We observed numerous recurrent CNVs including 10 involving loss or gain of Xp22.31, a region described in patients with and without epilepsy. Interpretation Copy number abnormalities play an important role in patients with epilepsy. Given that the diagnostic yield of CMA for epilepsy patients is similar to the yield in autism spectrum disorders and in prenatal diagnosis, for which published guidelines recommend testing with CMA, we recommend the implementation of CMA in the evaluation of unexplained epilepsy. PMID:24811917

  4. Bias of selection on human copy-number variants.

    Directory of Open Access Journals (Sweden)

    2006-02-01

    Full Text Available Although large-scale copy-number variation is an important contributor to conspecific genomic diversity, whether these variants frequently contribute to human phenotype differences remains unknown. If they have few functional consequences, then copy-number variants (CNVs might be expected both to be distributed uniformly throughout the human genome and to encode genes that are characteristic of the genome as a whole. We find that human CNVs are significantly overrepresented close to telomeres and centromeres and in simple tandem repeat sequences. Additionally, human CNVs were observed to be unusually enriched in those protein-coding genes that have experienced significantly elevated synonymous and nonsynonymous nucleotide substitution rates, estimated between single human and mouse orthologues. CNV genes encode disproportionately large numbers of secreted, olfactory, and immunity proteins, although they contain fewer than expected genes associated with Mendelian disease. Despite mouse CNVs also exhibiting a significant elevation in synonymous substitution rates, in most other respects they do not differ significantly from the genomic background. Nevertheless, they encode proteins that are depleted in olfactory function, and they exhibit significantly decreased amino acid sequence divergence. Natural selection appears to have acted discriminately among human CNV genes. The significant overabundance, within human CNVs, of genes associated with olfaction, immunity, protein secretion, and elevated coding sequence divergence, indicates that a subset may have been retained in the human population due to the adaptive benefit of increased gene dosage. By contrast, the functional characteristics of mouse CNVs either suggest that advantageous gene copies have been depleted during recent selective breeding of laboratory mouse strains or suggest that they were preferentially fixed as a consequence of the larger effective population size of wild mice. It

  5. Prognostic significance of centromere 17 copy number gain in breast cancer depends on breast cancer subtype.

    Science.gov (United States)

    Lee, Kyuongyul; Jang, Min Hye; Chung, Yul Ri; Lee, Yangkyu; Kang, Eunyoung; Kim, Sung-Won; Kim, Yu Jung; Kim, Jee Hyun; Kim, In Ah; Park, So Yeon

    2017-03-01

    Increased copy number of chromosome enumeration probe (CEP) targeting centromere 17 is frequently encountered during HER2 in situ hybridization (ISH) in breast cancer. The aim of this study was to clarify the clinicopathologic significance of CEP17 copy number gain in a relatively large series of breast cancer patients. We analyzed 945 cases of invasive breast cancers whose HER2 fluorescence ISH reports were available from 2004 to 2011 at a single institution and evaluated the association of CEP17 copy number gain with clinicopathologic features of tumors and patient survival. We detected 186 (19.7%) cases of CEP17 copy number gain (CEP17≥3.0) among 945 invasive breast cancers. In survival analysis, CEP17 copy number gain was not associated with disease-free survival of the patients in the whole group. Nonetheless, it was found to be an independent adverse prognostic factor in the HER2-negative group but not in the HER2-positive group. In further subgroup analyses, CEP17 copy number gain was revealed as an independent poor prognostic factor in HER2-negative and hormone receptor-positive breast cancers, and it was associated with aggressive histologic variables including high T stage, high histologic grade, lymphovascular invasion, p53 overexpression, and high Ki-67 proliferative index. In conclusion, we found that elevated CEP17 count can serve as a prognostic marker in luminal/HER2-negative subtype of invasive breast cancer. We advocate the use of the dual-colored fluorescence ISH using CEP17 rather than the single-colored one because it gives additional valuable information on CEP17 copy number alterations. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Eclipse period of R1 plasmids during downshift from elevated copy number: Nonrandom selection of copies for replication.

    Science.gov (United States)

    Olsson, Jan A; Berg, Otto; Nordström, Kurt; Dasgupta, Santanu

    2012-03-01

    The classical Meselson-Stahl density-shift method was used to study replication of pOU71, a runaway-replication derivative of plasmid R1 in Escherichia coli. The miniplasmid maintained the normal low copy number of R1 during steady growth at 30°C, but as growth temperatures were raised above 34°C, the copy number of the plasmid increased to higher levels, and at 42°C, it replicated without control in a runaway replication mode with lethal consequences for the host. The eclipse periods (minimum time between successive replication of the same DNA) of the plasmid shortened with rising copy numbers at increasing growth temperatures (Olsson et al., 2003). In this work, eclipse periods were measured during downshifts in copy number of pOU71 after it had replicated at 39 and 42°C, resulting in 7- and 50-fold higher than normal plasmid copy number per cell, respectively. Eclipse periods for plasmid replication, measured during copy number downshift, suggested that plasmid R1, normally selected randomly for replication, showed a bias such that a newly replicated DNA had a higher probability of replication compared to the bulk of the R1 population. However, even the unexpected nonrandom replication followed the copy number kinetics such that every generation, the plasmids underwent the normal inherited number of replication, n, independent of the actual number of plasmid copies in a newborn cell.

  7. Analysis of copy number variations among diverse cattle breeds

    Science.gov (United States)

    Liu, George E.; Hou, Yali; Zhu, Bin; Cardone, Maria Francesca; Jiang, Lu; Cellamare, Angelo; Mitra, Apratim; Alexander, Leeson J.; Coutinho, Luiz L.; Dell'Aquila, Maria Elena; Gasbarre, Lou C.; Lacalandra, Gianni; Li, Robert W.; Matukumalli, Lakshmi K.; Nonneman, Dan; de A. Regitano, Luciana C.; Smith, Tim P.L.; Song, Jiuzhou; Sonstegard, Tad S.; Van Tassell, Curt P.; Ventura, Mario; Eichler, Evan E.; McDaneld, Tara G.; Keele, John W.

    2010-01-01

    Genomic structural variation is an important and abundant source of genetic and phenotypic variation. Here, we describe the first systematic and genome-wide analysis of copy number variations (CNVs) in modern domesticated cattle using array comparative genomic hybridization (array CGH), quantitative PCR (qPCR), and fluorescent in situ hybridization (FISH). The array CGH panel included 90 animals from 11 Bos taurus, three Bos indicus, and three composite breeds for beef, dairy, or dual purpose. We identified over 200 candidate CNV regions (CNVRs) in total and 177 within known chromosomes, which harbor or are adjacent to gains or losses. These 177 high-confidence CNVRs cover 28.1 megabases or ∼1.07% of the genome. Over 50% of the CNVRs (89/177) were found in multiple animals or breeds and analysis revealed breed-specific frequency differences and reflected aspects of the known ancestry of these cattle breeds. Selected CNVs were further validated by independent methods using qPCR and FISH. Approximately 67% of the CNVRs (119/177) completely or partially span cattle genes and 61% of the CNVRs (108/177) directly overlap with segmental duplications. The CNVRs span about 400 annotated cattle genes that are significantly enriched for specific biological functions, such as immunity, lactation, reproduction, and rumination. Multiple gene families, including ULBP, have gone through ruminant lineage-specific gene amplification. We detected and confirmed marked differences in their CNV frequencies across diverse breeds, indicating that some cattle CNVs are likely to arise independently in breeds and contribute to breed differences. Our results provide a valuable resource beyond microsatellites and single nucleotide polymorphisms to explore the full dimension of genetic variability for future cattle genomic research. PMID:20212021

  8. A map of copy number variations in Chinese populations.

    Directory of Open Access Journals (Sweden)

    Haiyi Lou

    Full Text Available 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 them within and between populations. However, CNV study of Chinese minorities, which harbor the majority of genetic diversity of Chinese populations, has been underrepresented considering the same efforts in other populations. Here we constructed, to our knowledge, a first CNV map in seven Chinese populations representing the major linguistic groups in China with 1,440 CNV regions identified using Affymetrix SNP 6.0 Array. Considerable differences in distributions of CNV regions between populations and substantial population structures were observed. We showed that ∼35% of CNV regions identified in minority ethnic groups are not shared by Han Chinese population, indicating that the contribution of the minorities to genetic architecture of Chinese population could not be ignored. We further identified highly differentiated CNV regions between populations. For example, a common deletion in Dong and Zhuang (44.4% and 50%, which overlaps two keratin-associated protein genes contributing to the structure of hair fibers, was not observed in Han Chinese. Interestingly, the most differentiated CNV deletion between HapMap CEU and YRI containing CCL3L1 gene reported in previous studies was also the highest differentiated regions between Tibetan and other populations. Besides, by jointly analyzing CNVs and SNPs, we found a CNV region containing gene CTDSPL were in almost perfect linkage disequilibrium between flanking SNPs in Tibetan while not in other populations except HapMap CHD. Furthermore, we found the SNP taggability of CNVs in Chinese populations was much lower than that in European populations. Our results suggest the necessity of a full characterization of CNVs in Chinese populations, and the CNV map we constructed serves as a

  9. Statistical tools for transgene copy number estimation based on real-time PCR.

    Science.gov (United States)

    Yuan, Joshua S; Burris, Jason; Stewart, Nathan R; Mentewab, Ayalew; Stewart, C Neal

    2007-11-01

    As compared with traditional transgene copy number detection technologies such as Southern blot analysis, real-time PCR provides a fast, inexpensive and high-throughput alternative. However, the real-time PCR based transgene copy number estimation tends to be ambiguous and subjective stemming from the lack of proper statistical analysis and data quality control to render a reliable estimation of copy number with a prediction value. Despite the recent progresses in statistical analysis of real-time PCR, few publications have integrated these advancements in real-time PCR based transgene copy number determination. Three experimental designs and four data quality control integrated statistical models are presented. For the first method, external calibration curves are established for the transgene based on serially-diluted templates. The Ct number from a control transgenic event and putative transgenic event are compared to derive the transgene copy number or zygosity estimation. Simple linear regression and two group T-test procedures were combined to model the data from this design. For the second experimental design, standard curves were generated for both an internal reference gene and the transgene, and the copy number of transgene was compared with that of internal reference gene. Multiple regression models and ANOVA models can be employed to analyze the data and perform quality control for this approach. In the third experimental design, transgene copy number is compared with reference gene without a standard curve, but rather, is based directly on fluorescence data. Two different multiple regression models were proposed to analyze the data based on two different approaches of amplification efficiency integration. Our results highlight the importance of proper statistical treatment and quality control integration in real-time PCR-based transgene copy number determination. These statistical methods allow the real-time PCR-based transgene copy number estimation

  10. Systematic Inference of Copy-Number Genotypes from Personal Genome Sequencing Data Reveals Extensive Olfactory Receptor Gene Content Diversity

    Science.gov (United States)

    Waszak, Sebastian M.; Hasin, Yehudit; Zichner, Thomas; Olender, Tsviya; Keydar, Ifat; Khen, Miriam; Stütz, Adrian M.; Schlattl, Andreas; Lancet, Doron; Korbel, Jan O.

    2010-01-01

    Copy-number variations (CNVs) are widespread in the human genome, but comprehensive assignments of integer locus copy-numbers (i.e., copy-number genotypes) that, for example, enable discrimination of homozygous from heterozygous CNVs, have remained challenging. Here we present CopySeq, a novel computational approach with an underlying statistical framework that analyzes the depth-of-coverage of high-throughput DNA sequencing reads, and can incorporate paired-end and breakpoint junction analysis based CNV-analysis approaches, to infer locus copy-number genotypes. We benchmarked CopySeq by genotyping 500 chromosome 1 CNV regions in 150 personal genomes sequenced at low-coverage. The assessed copy-number genotypes were highly concordant with our performed qPCR experiments (Pearson correlation coefficient 0.94), and with the published results of two microarray platforms (95–99% concordance). We further demonstrated the utility of CopySeq for analyzing gene regions enriched for segmental duplications by comprehensively inferring copy-number genotypes in the CNV-enriched >800 olfactory receptor (OR) human gene and pseudogene loci. CopySeq revealed that OR loci display an extensive range of locus copy-numbers across individuals, with zero to two copies in some OR loci, and two to nine copies in others. Among genetic variants affecting OR loci we identified deleterious variants including CNVs and SNPs affecting ∼15% and ∼20% of the human OR gene repertoire, respectively, implying that genetic variants with a possible impact on smell perception are widespread. Finally, we found that for several OR loci the reference genome appears to represent a minor-frequency variant, implying a necessary revision of the OR repertoire for future functional studies. CopySeq can ascertain genomic structural variation in specific gene families as well as at a genome-wide scale, where it may enable the quantitative evaluation of CNVs in genome-wide association studies involving high

  11. Conditionally amplifiable BACs: switching from single-copy to high-copy vectors and genomic clones.

    Science.gov (United States)

    Wild, Jadwiga; Hradecna, Zdenka; Szybalski, Waclaw

    2002-09-01

    The widely used, very-low-copy BAC (bacterial artificial chromosome) vectors are the mainstay of present genomic research. The principal advantage of BACs is the high stability of inserted clones, but an important disadvantage is the low yield of DNA, both for vectors alone and when carrying genomic inserts. We describe here a novel class of single-copy/high-copy (SC/HC) pBAC/oriV vectors that retain all the advantages of low-copy BAC vectors, but are endowed with a conditional and tightly controlled oriV/TrfA amplification system that allows: (1) a yield of ~100 copies of the vector per host cell when conditionally induced with L-arabinose, and (2) analogous DNA amplification (only upon induction and with copy number depending on the insert size) of pBAC/oriV clones carrying >100-kb inserts. Amplifiable clones and libraries facilitate high-throughput DNA sequencing and other applications requiring HC plasmid DNA. To turn on DNA amplification, which is driven by the oriV origin of replication, we used copy-up mutations in the gene trfA whose expression was very tightly controlled by the araC-P(araBAD) promoter/regulator system. This system is inducible by L-arabinose, and could be further regulated by glucose and fucose. Amplification of DNA upon induction with L-arabinose and its modulation by glucose are robust and reliable. Furthermore, we discovered that addition of 0.2% D-glucose to the growth medium helped toward the objective of obtaining a real SC state for all BAC systems, thus enhancing the stability of their maintenance, which became equivalent to cloning into the host chromosome

  12. DNA copy number changes define spatial patterns of heterogeneity in colorectal cancer

    Science.gov (United States)

    Mamlouk, Soulafa; Childs, Liam Harold; Aust, Daniela; Heim, Daniel; Melching, Friederike; Oliveira, Cristiano; Wolf, Thomas; Durek, Pawel; Schumacher, Dirk; Bläker, Hendrik; von Winterfeld, Moritz; Gastl, Bastian; Möhr, Kerstin; Menne, Andrea; Zeugner, Silke; Redmer, Torben; Lenze, Dido; Tierling, Sascha; Möbs, Markus; Weichert, Wilko; Folprecht, Gunnar; Blanc, Eric; Beule, Dieter; Schäfer, Reinhold; Morkel, Markus; Klauschen, Frederick; Leser, Ulf; Sers, Christine

    2017-01-01

    Genetic heterogeneity between and within tumours is a major factor determining cancer progression and therapy response. Here we examined DNA sequence and DNA copy-number heterogeneity in colorectal cancer (CRC) by targeted high-depth sequencing of 100 most frequently altered genes. In 97 samples, with primary tumours and matched metastases from 27 patients, we observe inter-tumour concordance for coding mutations; in contrast, gene copy numbers are highly discordant between primary tumours and metastases as validated by fluorescent in situ hybridization. To further investigate intra-tumour heterogeneity, we dissected a single tumour into 68 spatially defined samples and sequenced them separately. We identify evenly distributed coding mutations in APC and TP53 in all tumour areas, yet highly variable gene copy numbers in numerous genes. 3D morpho-molecular reconstruction reveals two clusters with divergent copy number aberrations along the proximal–distal axis indicating that DNA copy number variations are a major source of tumour heterogeneity in CRC. PMID:28120820

  13. Copy number variation of KIR genes influences HIV-1 control

    DEFF Research Database (Denmark)

    Pelak, Kimberly; Need, Anna C; Fellay, Jacques;

    2011-01-01

    A genome-wide screen for large structural variants showed that a copy number variant (CNV) in the region encoding killer cell immunoglobulin-like receptors (KIR) associates with HIV-1 control as measured by plasma viral load at set point in individuals of European ancestry. This CNV encompasses...... the KIR3DL1-KIR3DS1 locus, encoding receptors that interact with specific HLA-Bw4 molecules to regulate the activation of lymphocyte subsets including natural killer (NK) cells. We quantified the number of copies of KIR3DS1 and KIR3DL1 in a large HIV-1 positive cohort, and showed that an increase in KIR3......DS1 count associates with a lower viral set point if its putative ligand is present (p = 0.00028), as does an increase in KIR3DL1 count in the presence of KIR3DS1 and appropriate ligands for both receptors (p = 0.0015). We further provide functional data that demonstrate that NK cells from...

  14. Copy Number Alterations and Methylation in Ewing's Sarcoma

    Directory of Open Access Journals (Sweden)

    Mona S. Jahromi

    2011-01-01

    Full Text Available Ewing's sarcoma is the second most common bone malignancy affecting children and young adults. The prognosis is especially poor in metastatic or relapsed disease. The cell of origin remains elusive, but the EWS-FLI1 fusion oncoprotein is present in the majority of cases. The understanding of the molecular basis of Ewing's sarcoma continues to progress slowly. EWS-FLI1 affects gene expression, but other factors must also be at work such as mutations, gene copy number alterations, and promoter methylation. This paper explores in depth two molecular aspects of Ewing's sarcoma: copy number alterations (CNAs and methylation. While CNAs consistently have been reported in Ewing's sarcoma, their clinical significance has been variable, most likely due to small sample size and tumor heterogeneity. Methylation is thought to be important in oncogenesis and balanced karyotype cancers such as Ewing's, yet it has received only minimal attention in prior studies. Future CNA and methylation studies will help to understand the molecular basis of this disease.

  15. Plasmid copy number noise in monoclonal populations of bacteria

    Science.gov (United States)

    Wong Ng, Jérôme; Chatenay, Didier; Robert, Jérôme; Poirier, Michael Guy

    2010-01-01

    Plasmids are extra chromosomal DNA that can confer to their hosts’ supplementary characteristics such as antibiotic resistance. Plasmids code for their copy number through their own replication frequency. Even though the biochemical networks underlying the plasmid copy number (PCN) regulation processes have been studied and modeled, no measurement of the heterogeneity in PCN within a whole population has been done. We have developed a fluorescent-based measurement system, which enables determination of the mean and noise in PCN within a monoclonal population of bacteria. Two different fluorescent protein reporters were inserted: one on the chromosome and the other on the plasmid. The fluorescence of these bacteria was measured with a microfluidic flow cytometry device. We show that our measurements are consistent with known plasmid characteristics. We find that the partitioning system lowers the PCN mean and standard deviation. Finally, bacterial populations were allowed to grow without selective pressure. In this case, we were able to determine the plasmid loss rate and growth inhibition effect.

  16. Quantification of Plasmid Copy Number with Single Colour Droplet Digital PCR.

    Science.gov (United States)

    Plotka, Magdalena; Wozniak, Mateusz; Kaczorowski, Tadeusz

    2017-01-01

    Bacteria can be considered as biological nanofactories that manufacture a cornucopia of bioproducts most notably recombinant proteins. As such, they must perfectly match with appropriate plasmid vectors to ensure successful overexpression of target genes. Among many parameters that correlate positively with protein productivity plasmid copy number plays pivotal role. Therefore, development of new and more accurate methods to assess this critical parameter will result in optimization of expression of plasmid-encoded genes. In this study, we present a simple and highly accurate method for quantifying plasmid copy number utilizing an EvaGreen single colour, droplet digital PCR. We demonstrate the effectiveness of this method by examining the copy number of the pBR322 vector within Escherichia coli DH5α cells. The obtained results were successfully validated by real-time PCR. However, we observed a strong dependency of the plasmid copy number on the method chosen for isolation of the total DNA. We found that application of silica-membrane-based columns for DNA purification or DNA isolation with use of bead-beating, a mechanical cell disruption lead to determination of an average of 20.5 or 7.3 plasmid copies per chromosome, respectively. We found that recovery of the chromosomal DNA from purification columns was less efficient than plasmid DNA (46.5 ± 1.9% and 87.4 ± 5.5%, respectively) which may lead to observed differences in plasmid copy number. Besides, the plasmid copy number variations dependent on DNA template isolation method, we found that droplet digital PCR is a very convenient method for measuring bacterial plasmid content. Careful determination of plasmid copy number is essential for better understanding and optimization of recombinant proteins production process. Droplet digital PCR is a very precise method that allows performing thousands of individual PCR reactions in a single tube. The ddPCR does not depend on running standard curves and is a

  17. Mitochondrial DNA copy number in peripheral blood cells declines with age and is associated with general health among elderly

    DEFF Research Database (Denmark)

    Mengel-From, Jonas; Thinggaard, Mikael; Dalgård, Christine

    2014-01-01

    compared to nuclear DNA, i.e. the mitochondrial DNA copy number, was measured by PCR technology and used as a proxy for the content of mitochondria copies. In 1,067 Danish twins and singletons (18-93 years of age), with the majority being elderly individuals, the estimated mean mitochondrial DNA copy...... an individual was more than twice as steep as observed in the cross-sectional analysis [decline of mtDNA content: -1.27; 95 % CI (-1.71; -0.82)]. Subjects with low mitochondrial DNA copy number had poorer outcomes in terms of cognitive performance, physical strength, self-rated health, and higher all......-cause mortality than subjects with high mitochondrial DNA copy number, also when age was controlled for. The copy number mortality association can contribute to the smaller decline in a cross-sectional sample of the population compared to the individual, longitudinal decline. This study suggests that high...

  18. Copy number analysis of the low-copy repeats at the primate NPHP1 locus by array comparative genomic hybridization.

    Science.gov (United States)

    Yuan, Bo; Liu, Pengfei; Rogers, Jeffrey; Lupski, James R

    2016-06-01

    Array comparative genomic hybridization (aCGH) has been widely used to detect copy number variants (CNVs) in both research and clinical settings. A customizable aCGH platform may greatly facilitate copy number analyses in genomic regions with higher-order complexity, such as low-copy repeats (LCRs). Here we present the aCGH analyses focusing on the 45 kb LCRs [1] at the NPHP1 region with diverse copy numbers in humans. Also, the interspecies aCGH analysis comparing human and nonhuman primates revealed dynamic copy number transitions of the human 45 kb LCR orthologues during primate evolution and therefore shed light on the origin of complexity at this locus. The original aCGH data are available at GEO under GSE73962.

  19. Selection of suitable endogenous reference genes for relative copy number detection in sugarcane.

    Science.gov (United States)

    Xue, Bantong; Guo, Jinlong; Que, Youxiong; Fu, Zhiwei; Wu, Luguang; Xu, Liping

    2014-05-19

    Transgene copy number has a great impact on the expression level and stability of exogenous gene in transgenic plants. Proper selection of endogenous reference genes is necessary for detection of genetic components in genetically modification (GM) crops by quantitative real-time PCR (qPCR) or by qualitative PCR approach, especially in sugarcane with polyploid and aneuploid genomic structure. qPCR technique has been widely accepted as an accurate, time-saving method on determination of copy numbers in transgenic plants and on detection of genetically modified plants to meet the regulatory and legislative requirement. In this study, to find a suitable endogenous reference gene and its real-time PCR assay for sugarcane (Saccharum spp. hybrids) DNA content quantification, we evaluated a set of potential "single copy" genes including P4H, APRT, ENOL, CYC, TST and PRR, through qualitative PCR and absolute quantitative PCR. Based on copy number comparisons among different sugarcane genotypes, including five S. officinarum, one S. spontaneum and two S. spp. hybrids, these endogenous genes fell into three groups: ENOL-3--high copy number group, TST-1 and PRR-1--medium copy number group, P4H-1, APRT-2 and CYC-2--low copy number group. Among these tested genes, P4H, APRT and CYC were the most stable, while ENOL and TST were the least stable across different sugarcane genotypes. Therefore, three primer pairs of P4H-3, APRT-2 and CYC-2 were then selected as the suitable reference gene primer pairs for sugarcane. The test of multi-target reference genes revealed that the APRT gene was a specific amplicon, suggesting this gene is the most suitable to be used as an endogenous reference target for sugarcane DNA content quantification. These results should be helpful for establishing accurate and reliable qualitative and quantitative PCR analysis of GM sugarcane.

  20. Germline copy number variation and ovarian cancer survival

    Directory of Open Access Journals (Sweden)

    Brooke L Fridley

    2012-08-01

    Full Text Available Copy number variants (CNVs have been implicated in many complex diseases. We examined whether inherited CNVs were associated with overall survival among women with invasive epithelial ovarian cancer. Germline DNA from 1,056 cases (494 deceased, average of 3.7 years follow-up was interrogated with the Illumina 610quad genome-wide array containing, after quality control exclusions, 581,903 single nucleotide polymorphisms (SNPs and 17,917 CNV probes. Comprehensive analysis capitalized upon the strengths of three complementary approaches to CNV classification. First, to identify small CNVs, single markers were evaluated and, where associated with survival, consecutive markers were combined. Two chromosomal regions were associated with survival using this approach (14q31.3 rs2274736 p=1.59x10-6, p=0.001; 22q13.31 rs2285164 p=4.01x10-5, p=0.009, but were not significant after multiple testing correction. Second, to identify large CNVs, genome-wide segmentation was conducted to characterize chromosomal gains and losses, and association with survival was evaluated by segment. Four regions were associated with survival (1q21.3 loss p=0.005, 5p14.1 loss p=0.004, 9p23 loss p=0.002, and 15q22.31 gain p=0.002; however, again, after correcting for multiple testing, no regions were statistically significant, and none were in common with the single-marker approach. Finally, to evaluate associations with general amounts of copy number changes across the genome, we estimated CNV burden based on genome-wide numbers of gains and losses; no associations with survival were observed (p>0.40. Although CNVs that were not well-covered by the Illumina 610quad array merit investigation, these data suggest no association between inherited CNVs and survival after ovarian cancer.

  1. Quantification of protein copy number in single mitochondria: The Bcl-2 family proteins.

    Science.gov (United States)

    Chen, Chaoxiang; Zhang, Xiang; Zhang, Shuyue; Zhu, Shaobin; Xu, Jingyi; Zheng, Yan; Han, Jinyan; Zeng, Jin-Zhang; Yan, Xiaomei

    2015-12-15

    Bcl-2 family proteins, represented by antiapoptotic protein Bcl-2 and proapoptotic protein Bax, are key regulators of mitochondria-mediated apoptosis pathway. To build a quantitative model of how Bcl-2 family protein interactions control mitochondrial outer membrane permeabilization and subsequent cytochrome c release, it is essential to know the number of proteins in individual mitochondria. Here, we report an effective method to quantify the copy number and distribution of proteins in single mitochondria via immunofluorescent labeling and sensitive detection by a laboratory-built high sensitivity flow cytometer (HSFCM). Mitochondria isolated from HeLa cells were stained with Alexa Fluor 488 (AF488)-labeled monoclonal antibodies specifically targeting Bcl-2 or Bax and with nucleic acid dye. A series of fluorescent nanospheres with fluorescence intensity calibrated in the unit of molecules of equivalent soluble fluorochrome (MESF)-AF488 were used to construct a calibration curve for converting the immunofluorescence of a single mitochondrion to the number of antibodies bound to it and then to the number of proteins per mitochondrion. Under the normal condition, the measured mean copy numbers were 1300 and 220 per mitochondrion for Bcl-2 and Bax, respectively. A significant variation in protein copy number was identified, which ranged from 130 to 6000 (2.5-97.5%) for Bcl-2 and from 65 to 700 (2.5-97.5%) for Bax, respectively. We observed an approximately 4.4 fold increase of Bax copy number per mitochondrion upon 9h of apoptosis stimulation while the abundance of Bcl-2 remained almost unchanged. To the best of our knowledge, this is the first report of Bcl-2 family protein copy number and variance in single mitochondria. Collectively, we demonstrate that the HSFCM-based immunoassay provides a rapid and sensitive method for determining protein copy number distribution in single mitochondria. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Enhancing yields of low and single copy number plasmid DNAs from Escherichia coli cells.

    Science.gov (United States)

    Wood, Whitney N; Smith, Kyle D; Ream, Jennifer A; Kevin Lewis, L

    2017-02-01

    Many plasmids used for gene cloning and heterologous protein expression in Escherichia coli cells are low copy number or single copy number plasmids. The extraction of these types of plasmids from small bacterial cell cultures produces low DNA yields. In this study, we have quantitated yields of low copy and single copy number plasmid DNAs after growth of cells in four widely used broths (SB, SOC, TB, and 2xYT) and compared results to those obtained with LB, the most common E. coli cell growth medium. TB (terrific broth) consistently generated the greatest amount of plasmid DNA, in agreement with its ability to produce higher cell titers. The superiority of TB was primarily due to its high levels of yeast extract (24g/L) and was independent of glycerol, a unique component of this broth. Interestingly, simply preparing LB with similarly high levels of yeast extract (LB24 broth) resulted in plasmid yields that were equivalent to those of TB. By contrast, increasing ampicillin concentration to enhance plasmid retention did not improve plasmid DNA recovery. These experiments demonstrate that yields of low and single copy number plasmid DNAs from minipreps can be strongly enhanced using simple and inexpensive media. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Accurate and objective copy number profiling using real-time quantitative PCR.

    Science.gov (United States)

    D'haene, Barbara; Vandesompele, Jo; Hellemans, Jan

    2010-04-01

    Copy number changes are known to be involved in numerous human genetic disorders. In this context, qPCR-based copy number screening may serve as the method of choice for targeted screening of the relevant disease genes and their surrounding regulatory landscapes. qPCR has many advantages over alternative methods, such as its low consumable and instrumentation costs, fast turnaround and assay development time, high sensitivity and open format (independent of a single supplier). In this chapter we provide all relevant information for a successfully implement of qPCR-based copy number analysis. We emphasize the significance of thorough in silico and empirical validation of the primers, the need for a well thought-out experiment design, and the importance of quality controls along the entire workflow. Furthermore, we suggest an appropriate and practical way to calculate copy numbers and to objectively interpret the results. The provided guidelines will most certainly improve the quality and reliability of your qPCR-based copy number screening.

  4. Dietary starch intake modifies the relation between copy number variation in the salivary amylase gene and BMI.

    Science.gov (United States)

    Rukh, Gull; Ericson, Ulrika; Andersson-Assarsson, Johanna; Orho-Melander, Marju; Sonestedt, Emily

    2017-07-01

    Background: Studies have shown conflicting associations between the salivary amylase gene (AMY1) copy number and obesity. Salivary amylase initiates starch digestion in the oral cavity; starch is a major source of energy in the diet.Objective: We investigated the association between AMY1 copy number and obesity traits, and the effect of the interaction between AMY1 copy number and starch intake on these obesity traits.Design: We first assessed the association between AMY1 copy number (genotyped by digital droplet polymerase chain reaction) and obesity traits in 4800 individuals without diabetes (mean age: 57 y; 60% female) from the Malmö Diet and Cancer Cohort. Then we analyzed interactions between AMY1 copy number and energy-adjusted starch intake (obtained by a modified diet history method) on body mass index (BMI) and body fat percentage.Results:AMY1 copy number was not associated with BMI (P = 0.80) or body fat percentage (P = 0.38). We observed a significant effect of the interaction between AMY1 copy number and starch intake on BMI (P-interaction = 0.007) and body fat percentage (P-interaction = 0.03). Upon stratification by dietary starch intake, BMI tended to decrease with increasing AMY1 copy numbers in the low-starch intake group (P = 0.07) and tended to increase with increasing AMY1 copy numbers in the high-starch intake group (P = 0.08). The lowest mean BMI was observed in the group of participants with a low AMY1 copy number and a high dietary intake of starch.Conclusions: Our findings suggest an effect of the interaction between starch intake and AMY1 copy number on obesity. Individuals with high starch intake but low genetic capacity to digest starch had the lowest BMI, potentially because larger amounts of undigested starch are transported through the gastrointestinal tract, contributing to fewer calories extracted from ingested starch. © 2017 American Society for Nutrition.

  5. Copy number variations of the ATP-binding cassette transporter ABCC6 gene and its pseudogenes

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    Kringen Marianne K

    2012-08-01

    Full Text Available Abstract Background The ATP-binding cassette transporter ABCC6 gene is located on chromosome 16 between its two pseudogenes (ABCC6P1 and ABCC6P2. Previously, we have shown that ABCC6P1 is transcribed and affects ABCC6 at the transcriptional level. In this study we aimed to determine copy number variations of ABCC6, ABCC6P1 and ABCC6P2 in different populations. Moreover, we sought to study the transcription pattern of ABCC6 and ABCC6 pseudogenes in 39 different human tissues. Findings Genomic DNA from healthy individuals from five populations, Chinese (n = 24, Middle East (n = 20, Mexicans (n = 24, Caucasians (n = 50 and Africans (n = 24, were examined for copy number variations of ABCC6 and its pseudogenes by pyrosequencing and quantitative PCR. Copy number variation of ABCC6 was very rare (2/142; 1.4%. However, one or three copies of ABCC6P1 were relatively common (3% and 8%, respectively. Only one person had a single copy of ABCC6P2 while none had three copies. In Chinese, deletions or duplications of ABCC6P1 were more frequent than in any other population (9/24; 37.5%. The transcription pattern of ABCC6P2 was highly similar to ABCC6 and ABCC6P1, with highest transcription in liver and kidney. Interestingly, the total transcription level of pseudogenes, ABCC6P1 + ABCC6P2, was higher than ABCC6 in most tissues, including liver and kidney. Conclusions Copy number variations of the ABCC6 pseudogenes are quite common, especially in populations of Chinese ancestry. The expression pattern of ABCC6P2 in 39 human tissues was highly similar to that of ABCC6 and ABCC6P1 suggesting similar regulatory mechanisms for ABCC6 and its pseudogenes.

  6. Atrazine exposure elicits copy number alterations in the zebrafish genome.

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    Wirbisky, Sara E; Freeman, Jennifer L

    2017-04-01

    Atrazine is an agricultural herbicide used throughout the Midwestern United States that frequently contaminates potable water supplies resulting in human exposure. Using the zebrafish model system, an embryonic atrazine exposure was previously reported to decrease spawning rates with an increase in progesterone and ovarian follicular atresia in adult females. In addition, alterations in genes associated with distinct molecular pathways of the endocrine system were observed in brain and gonad tissue of the adult females and males. Current hypotheses for mechanistic changes in the developmental origins of health and disease include genetic (e.g., copy number alterations) or epigenetic (e.g., DNA methylation) mechanisms. As such, in the current study we investigated whether an atrazine exposure would generate copy number alterations (CNAs) in the zebrafish genome. A zebrafish fibroblast cell line was used to limit detection to CNAs caused by the chemical exposure. First, cells were exposed to a range of atrazine concentrations and a crystal violet assay was completed, showing confluency decreased by ~60% at 46.3μM. Cells were then exposed to 0, 0.463, 4.63, or 46.3μM atrazine and array comparative genomic hybridization completed. Results showed 34, 21, and 44 CNAs in the 0.463, 4.63, and 46.3μM treatments, respectively. Furthermore, CNAs were associated with previously reported gene expression alterations in adult male and female zebrafish. This study demonstrates that atrazine exposure can generate CNAs that are linked to gene expression alterations observed in adult zebrafish exposed to atrazine during embryogenesis providing a mechanism of the developmental origins of atrazine endocrine disruption. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Data analysis considerations for detecting copy number changes in formalin-fixed, paraffin-embedded tissues.

    Science.gov (United States)

    Jacobs, Sharoni

    2012-11-01

    The Whole Genome Sampling Analysis (WGSA) assay in combination with Affymetrix GeneChip Mapping Arrays is used for copy number analysis of high-quality DNA samples (i.e., samples that have been collected from blood, fresh or frozen tissue, or cell lines). Formalin-fixed, paraffin-embedded (FFPE) samples, however, represent the most prevalent form of archived clinical samples, but they provide additional challenges for molecular assays. FFPE processing usually results in the degradation of FFPE DNA and in the contamination and chemical modification of these DNA samples. In this article, we describe the steps needed to obtain reliable copy number predictions from degraded and contaminated FFPE samples.

  8. Integrated analysis of DNA copy number and gene expression microarray data using gene sets

    NARCIS (Netherlands)

    R.X. de Menezes (Renee); M. Boetzer (Marten); M. Sieswerda (Melle); G.J.B. van Ommen; J.M. Boer (Judith)

    2009-01-01

    textabstractBackground: Genes that play an important role in tumorigenesis are expected to show association between DNA copy number and RNA expression. Optimal power to find such associations can only be achieved if analysing copy number and gene expression jointly. Furthermore, some copy number

  9. Cyanobacteria Maintain Constant Protein Concentration despite Genome Copy-Number Variation.

    Science.gov (United States)

    Zheng, Xiao-Yu; O'Shea, Erin K

    2017-04-18

    The cyanobacterium Synechococcus elongatus PCC 7942 has multiple copies of its single chromosome, and the copy number varies in individual cells, providing an ideal system to study the effect of genome copy-number variation on cell size and gene expression. Using single-cell fluorescence imaging, we found that protein concentration remained constant across individual cells regardless of genome copy number. Cell volume and the total protein amount from a single gene were both positively, linearly correlated with genome copy number, suggesting that changes in cell volume play an important role in buffering genome copy-number variance. This study provides a quantitative examination of gene expression regulation in cells with variable genome copies and sheds light on the compensation mechanisms for variance in genome copy number. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  10. Copy number variants in the kallikrein gene cluster.

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    Pernilla Lindahl

    Full Text Available The kallikrein gene family (KLK1-KLK15 is the largest contiguous group of protease genes within the human genome and is associated with both risk and outcome of cancer and other diseases. We searched for copy number variants in all KLK genes using quantitative PCR analysis and analysis of inheritance patterns of single nucleotide polymorphisms. Two deletions were identified: one 2235-bp deletion in KLK9 present in 1.2% of alleles, and one 3394-bp deletion in KLK15 present in 4.0% of alleles. Each deletion eliminated one complete exon and created out-of-frame coding that eliminated the catalytic triad of the resulting truncated gene product, which therefore likely is a non-functional protein. Deletion breakpoints identified by DNA sequencing located the KLK9 deletion breakpoint to a long interspersed element (LINE repeated sequence, while the deletion in KLK15 is located in a single copy sequence. To search for an association between each deletion and risk of prostate cancer (PC, we analyzed a cohort of 667 biopsied men (266 PC cases and 401 men with no evidence of PC at biopsy using short deletion-specific PCR assays. There was no association between evidence of PC in this cohort and the presence of either gene deletion. Haplotyping revealed a single origin of each deletion, with most recent common ancestor estimates of 3000-8000 and 6000-14 000 years for the deletions in KLK9 and KLK15, respectively. The presence of the deletions on the same haplotypes in 1000 Genomes data of both European and African populations indicate an early origin of both deletions. The old age in combination with homozygous presence of loss-of-function variants suggests that some kallikrein-related peptidases have non-essential functions.

  11. Decoding NF1 Intragenic Copy-Number Variations.

    Science.gov (United States)

    Hsiao, Meng-Chang; Piotrowski, Arkadiusz; Callens, Tom; Fu, Chuanhua; Wimmer, Katharina; Claes, Kathleen B M; Messiaen, Ludwine

    2015-08-06

    Genomic rearrangements can cause both Mendelian and complex disorders. Currently, several major mechanisms causing genomic rearrangements, such as non-allelic homologous recombination (NAHR), non-homologous end joining (NHEJ), fork stalling and template switching (FoSTeS), and microhomology-mediated break-induced replication (MMBIR), have been proposed. However, to what extent these mechanisms contribute to gene-specific pathogenic copy-number variations (CNVs) remains understudied. Furthermore, few studies have resolved these pathogenic alterations at the nucleotide-level. Accordingly, our aim was to explore which mechanisms contribute to a large, unique set of locus-specific non-recurrent genomic rearrangements causing the genetic neurocutaneous disorder neurofibromatosis type 1 (NF1). Through breakpoint-spanning PCR as well as array comparative genomic hybridization, we have identified the breakpoints in 85 unrelated individuals carrying an NF1 intragenic CNV. Furthermore, we characterized the likely rearrangement mechanisms of these 85 CNVs, along with those of two additional previously published NF1 intragenic CNVs. Unlike the most typical recurrent rearrangements mediated by flanking low-copy repeats (LCRs), NF1 intragenic rearrangements vary in size, location, and rearrangement mechanisms. We propose the DNA-replication-based mechanisms comprising both FoSTeS and/or MMBIR and serial replication stalling to be the predominant mechanisms leading to NF1 intragenic CNVs. In addition to the loop within a 197-bp palindrome located in intron 40, four Alu elements located in introns 1, 2, 3, and 50 were also identified as intragenic-rearrangement hotspots within NF1.

  12. High Species C Human Adenovirus Genome Copy Numbers in the Treated Water Supply of a Neotropical Area of the Central-West Region of Brazil.

    Science.gov (United States)

    Silva, Hugo D; Fongaro, Gislaine; Garcíazapata, Marco T A; Melo, Arthur T O; Silveira-Lacerda, Elisângela P; de Faria, Karla M S; Anunciação, Carlos E

    2015-09-01

    There is little information about the presence of human adenovirus (HAdV) in drinking water in Neotropical regions. Thus, the present study sought to conduct quantification and molecular characterization of HAdVs detected in treated water samples from an area of the Cerrado ecoregion of Brazil. Between August and November 2012, samples were collected from four treated water reservoirs and their respective sites along the water distribution network of the city of Goiânia, for a total of 80 samples. All samples were concentrated and analyzed by qPCR, and selected samples were sequenced. Overall, 76.6 (10(0)-10(9) GC mL(-1)) and 37.5% (10(1)-10(8) GC mL(-1)) of samples drawn from reservoirs and their distribution sites, respectively, were positive for virus by qPCR. All samples selected for sequencing were characterized as species C human adenovirus. Such high HAdV counts have in treated water samples. This finding merits special attention, particularly from the sanitation authorities, because the high number of GC mL(-1) may be an indicative of risk to human health.

  13. Distribution of Disease-Associated Copy Number Variants across Distinct Disorders of Cognitive Development

    Science.gov (United States)

    Pescosolido, Matthew F.; Gamsiz, Ece D.; Nagpal, Shailender; Morrow, Eric M.

    2013-01-01

    Objective: The purpose of the present study was to discover the extent to which distinct "DSM" disorders share large, highly recurrent copy number variants (CNVs) as susceptibility factors. We also sought to identify gene mechanisms common to groups of diagnoses and/or specific to a given diagnosis based on associations with CNVs. Method:…

  14. Distribution of Disease-Associated Copy Number Variants across Distinct Disorders of Cognitive Development

    Science.gov (United States)

    Pescosolido, Matthew F.; Gamsiz, Ece D.; Nagpal, Shailender; Morrow, Eric M.

    2013-01-01

    Objective: The purpose of the present study was to discover the extent to which distinct "DSM" disorders share large, highly recurrent copy number variants (CNVs) as susceptibility factors. We also sought to identify gene mechanisms common to groups of diagnoses and/or specific to a given diagnosis based on associations with CNVs. Method:…

  15. Amylase activity is associated with AMY2B copy numbers in dog: implications for dog domestication, diet and diabetes.

    Science.gov (United States)

    Arendt, Maja; Fall, Tove; Lindblad-Toh, Kerstin; Axelsson, Erik

    2014-10-01

    High amylase activity in dogs is associated with a drastic increase in copy numbers of the gene coding for pancreatic amylase, AMY2B, that likely allowed dogs to thrive on a relatively starch-rich diet during early dog domestication. Although most dogs thus probably digest starch more efficiently than do wolves, AMY2B copy numbers vary widely within the dog population, and it is not clear how this variation affects the individual ability to handle starch nor how it affects dog health. In humans, copy numbers of the gene coding for salivary amylase, AMY1, correlate with both salivary amylase levels and enzyme activity, and high amylase activity is related to improved glycemic homeostasis and lower frequencies of metabolic syndrome. Here, we investigate the relationship between AMY2B copy numbers and serum amylase activity in dogs and show that amylase activity correlates with AMY2B copy numbers. We then describe how AMY2B copy numbers vary in individuals from 20 dog breeds and find strong breed-dependent patterns, indicating that the ability to digest starch varies both at the breed and individual level. Finally, to test whether AMY2B copy number is strongly associated with the risk of developing diabetes mellitus, we compare copy numbers in cases and controls as well as in breeds with varying diabetes susceptibility. Although we see no such association here, future studies using larger cohorts are needed before excluding a possible link between AMY2B and diabetes mellitus.

  16. Amylase activity is associated with AMY2B copy numbers in dog: implications for dog domestication, diet and diabetes

    Science.gov (United States)

    Arendt, Maja; Fall, Tove; Lindblad-Toh, Kerstin; Axelsson, Erik

    2014-01-01

    High amylase activity in dogs is associated with a drastic increase in copy numbers of the gene coding for pancreatic amylase, AMY2B, that likely allowed dogs to thrive on a relatively starch-rich diet during early dog domestication. Although most dogs thus probably digest starch more efficiently than do wolves, AMY2B copy numbers vary widely within the dog population, and it is not clear how this variation affects the individual ability to handle starch nor how it affects dog health. In humans, copy numbers of the gene coding for salivary amylase, AMY1, correlate with both salivary amylase levels and enzyme activity, and high amylase activity is related to improved glycemic homeostasis and lower frequencies of metabolic syndrome. Here, we investigate the relationship between AMY2B copy numbers and serum amylase activity in dogs and show that amylase activity correlates with AMY2B copy numbers. We then describe how AMY2B copy numbers vary in individuals from 20 dog breeds and find strong breed-dependent patterns, indicating that the ability to digest starch varies both at the breed and individual level. Finally, to test whether AMY2B copy number is strongly associated with the risk of developing diabetes mellitus, we compare copy numbers in cases and controls as well as in breeds with varying diabetes susceptibility. Although we see no such association here, future studies using larger cohorts are needed before excluding a possible link between AMY2B and diabetes mellitus. PMID:24975239

  17. The association between DNA copy number aberrations at chromosome 5q22 and gastric cancer.

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    Pei-Chien Tsai

    Full Text Available BACKGROUND: Gastric cancer is common cancer. Discovering novel genetic biomarkers might help to identify high-risk individuals. Copy number variation (CNV has recently been shown to influence risk for several cancers. The aim of the present study was sought to test the association between copy number at a variant region and GC. METHODS: A total of 110 gastric cancer patients and 325 healthy volunteers were enrolled in this study. We searched for a CNV and found a CNV (Variation 7468 containing part of the APC gene, the SRP19 gene and the REEP5 gene. We chose four probes targeting at APC-intron8, APC-exon9, SRP19 and REEP5 to interrogate this CNV. Specific Taqman probes labeled by different reporter fluorophores were used in a real-time PCR platform to obtain copy number. Both the original non-integer data and transformed integer data on copy number were used for analyses. RESULTS: Gastric caner patients had a lower non-integer copy number than controls for the APC-exon9 probe (Adjusted p = 0.026 and SRP19 probe (Adjusted p = 0.002. The analysis of integer copy number yielded a similar pattern although less significant (Adjusted p = 0.07 for APC-exon9 probe and Adjusted p = 0.02 for SRP19 probe. CONCLUSIONS: Losses of a CNV at 5q22, especially in the DNA region surrounding APC-exon 9, may be associated with a higher risk of gastric cancer.

  18. Copy number variations of 11 macronuclear chromosomes and their gene expression in Oxytricha trifallax.

    Science.gov (United States)

    Xu, Ke; Doak, Thomas G; Lipps, Hans J; Wang, Jingmei; Swart, Estienne C; Chang, Wei-Jen

    2012-08-15

    Ciliated protozoa are peculiar for their nuclear dimorphism, wherein two types of nuclei divide nuclear functions: a germline micronucleus (MIC) is transcriptionally inert during vegetative growth, but serves as the genetic blueprint for the somatic macronucleus (MAC), which is responsible for all transcripts supporting cell growth and reproduction. While all the advantages/disadvantages associated with nuclear dimorphism are not clear, an essential advantage seems to be the ability to produce a highly polyploid MAC, which then allows for the maintenance of extremely large single cells - many ciliate cells are larger than small metazoa. In some ciliate classes, chromosomes in the MAC are extensively fragmented to create extremely short chromosomes that often carry single genes, and these chromosomes may be present in different copy numbers, resulting in different ploidies. While using gene copy number to regulate gene expression is limited in most eukaryotic systems, the extensive fragmentation in some ciliate classes provides this opportunity to every MAC gene. However, it is still unclear if this mechanism is in fact used extensively in these ciliates. To address this, we have quantified copy numbers of 11 MAC chromosomes and their gene expression in Oxytricha trifallax (CI: Spirotrichea). We compared copy numbers between two subpopulations of O. trifallax, and copy numbers of 7 orthologous genes between O. trifallax and the closely related Stylonychia lemnae. We show that copy numbers of MAC chromosomes are variable, dynamic, and positively correlated to gene expression. These features might be conserved in all spirotrichs, and might exist in other classes of ciliates with heavily fragmented MAC chromosomes.

  19. Selection of Suitable Endogenous Reference Genes for Relative Copy Number Detection in Sugarcane

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    Bantong Xue

    2014-05-01

    Full Text Available Transgene copy number has a great impact on the expression level and stability of exogenous gene in transgenic plants. Proper selection of endogenous reference genes is necessary for detection of genetic components in genetically modification (GM crops by quantitative real-time PCR (qPCR or by qualitative PCR approach, especially in sugarcane with polyploid and aneuploid genomic structure. qPCR technique has been widely accepted as an accurate, time-saving method on determination of copy numbers in transgenic plants and on detection of genetically modified plants to meet the regulatory and legislative requirement. In this study, to find a suitable endogenous reference gene and its real-time PCR assay for sugarcane (Saccharum spp. hybrids DNA content quantification, we evaluated a set of potential “single copy” genes including P4H, APRT, ENOL, CYC, TST and PRR, through qualitative PCR and absolute quantitative PCR. Based on copy number comparisons among different sugarcane genotypes, including five S. officinarum, one S. spontaneum and two S. spp. hybrids, these endogenous genes fell into three groups: ENOL-3—high copy number group, TST-1 and PRR-1—medium copy number group, P4H-1, APRT-2 and CYC-2—low copy number group. Among these tested genes, P4H, APRT and CYC were the most stable, while ENOL and TST were the least stable across different sugarcane genotypes. Therefore, three primer pairs of P4H-3, APRT-2 and CYC-2 were then selected as the suitable reference gene primer pairs for sugarcane. The test of multi-target reference genes revealed that the APRT gene was a specific amplicon, suggesting this gene is the most suitable to be used as an endogenous reference target for sugarcane DNA content quantification. These results should be helpful for establishing accurate and reliable qualitative and quantitative PCR analysis of GM sugarcane.

  20. Reliable transgene-independent method for determining Sleeping Beauty transposon copy numbers

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    Kolacsek Orsolya

    2011-03-01

    Full Text Available Abstract Background The transposon-based gene delivery technique is emerging as a method of choice for gene therapy. The Sleeping Beauty (SB system has become one of the most favored methods, because of its efficiency and its random integration profile. Copy-number determination of the delivered transgene is a crucial task, but a universal method for measuring this is lacking. In this paper, we show that a real-time quantitative PCR-based, transgene-independent (qPCR-TI method is able to determine SB transposon copy numbers regardless of the genetic cargo. Results We designed a specific PCR assay to amplify the left inverted repeat-direct repeat region of SB, and used it together with the single-copy control gene RPPH1 and a reference genomic DNA of known copy number. The qPCR-TI method allowed rapid and accurate determination of SB transposon copy numbers in various cell types, including human embryonic stem cells. We also found that this sensitive, rapid, highly reproducible and non-radioactive method is just as accurate and reliable as the widely used blotting techniques or the transposon display method. Because the assay is specific for the inverted repeat region of the transposon, it could be used in any system where the SB transposon is the genetic vehicle. Conclusions We have developed a transgene-independent method to determine copy numbers of transgenes delivered by the SB transposon system. The technique is based on a quantitative real-time PCR detection method, offering a sensitive, non-radioactive, rapid and accurate approach, which has a potential to be used for gene therapy.

  1. Genomic variability in Mexican chicken population using Copy Number Variation

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    Erica Gorla

    2017-05-01

    Full Text Available Copy number variants (CNVs are polymorphisms which influence phenotypic variation and are an important source of genetic variability [1]. In Mexico the backyard poultry population is a unique widespread Creole chicken (Gallus gallus domesticus population, an undefined cross among different breeds brought to Mexico from Europe and under natural selection for almost 500 years [2-3]. The aim of this study was to investigate genomic variation in the Mexican chicken population using CNVs. A total of 256 DNA samples genotyped with Axiom® Genome-Wide Chicken Genotyping Array were used in the analyses. The individual CNV calling, based on log-R ratio and B-allele frequency values, was performed using the Hidden Markov Model (HMM of PennCNV software on the autosomes [4-5]. CNVs were summarized to CNV regions (CNVRs at a population level (i.e. overlapping CNVs, using BEDTools. The HMM detected a total of 1924 CNVs in the genome of 256 samples resulting, at population level, in 1216 CNV regions, of which 959 gains, 226 losses and 31 complex CNVRs (i.e. containing both losses and gains, covering a total of 47 Mb of sequence length corresponding to 5,12 % of the chicken galGal4 assembly autosome. A comparison among this study and 7 previous reports about CNVs in chicken was performed, finding that the 1,216 CNVRs detected in this study overlap with 617 regions (51% mapped by others studies.   This study allowed a deep insight into the structural variation in the genome of unselected Mexican chicken population, which up to now has not been never genetically characterized with SNP markers. Based on a cluster analysis (pvclust – R package on CNV markers the population, even if presenting extreme morphological variation, does not resulted divided in differentiated genetic subpopulations. Finally this study provides a CNV map based on the 600K SNP chip array jointly with a genome-wide gene copy number estimates in Mexican chicken population.

  2. Copy number gain of VCX, X-linked multi-copy gene, leads to cell proliferation and apoptosis during spermatogenesis

    Science.gov (United States)

    Ji, Juan; Qin, Yufeng; Wang, Rong; Huang, Zhenyao; Zhang, Yan; Zhou, Ran; Song, Ling; Ling, Xiufeng; Hu, Zhibin; Miao, Dengshun; Shen, Hongbing; Xia, Yankai; Wang, Xinru; Lu, Chuncheng

    2016-01-01

    Male factor infertility affects one-sixth of couples worldwide, and non-obstructive azoospermia (NOA) is one of the most severe forms. In recent years there has been increasing evidence to implicate the participation of X chromosome in the process of spermatogenesis. To uncover the roles of X-linked multi-copy genes in spermatogenesis, we performed systematic analysis of X-linked gene copy number variations (CNVs) and Y chromosome haplogrouping in 447 idiopathic NOA patients and 485 healthy controls. Interestingly, the frequency of individuals with abnormal level copy of Variable charge, X-linked (VCX) was significantly different between cases and controls after multiple test correction (p = 5.10 × 10−5). To discriminate the effect of gain/loss copies in these genes, we analyzed the frequency of X-linked multi-copy genes in subjects among subdivided groups. Our results demonstrated that individuals with increased copy numbers of Nuclear RNA export factor 2 (NXF2) (p = 9.21 × 10−8) and VCX (p = 1.97 × 10−4) conferred the risk of NOA. In vitro analysis demonstrated that increasing copy number of VCX could upregulate the gene expression and regulate cell proliferation and apoptosis. Our study establishes a robust association between the VCX CNVs and NOA risk. PMID:27705943

  3. Copy number gain of VCX, X-linked multi-copy gene, leads to cell proliferation and apoptosis during spermatogenesis.

    Science.gov (United States)

    Ji, Juan; Qin, Yufeng; Wang, Rong; Huang, Zhenyao; Zhang, Yan; Zhou, Ran; Song, Ling; Ling, Xiufeng; Hu, Zhibin; Miao, Dengshun; Shen, Hongbing; Xia, Yankai; Wang, Xinru; Lu, Chuncheng

    2016-11-29

    Male factor infertility affects one-sixth of couples worldwide, and non-obstructive azoospermia (NOA) is one of the most severe forms. In recent years there has been increasing evidence to implicate the participation of X chromosome in the process of spermatogenesis. To uncover the roles of X-linked multi-copy genes in spermatogenesis, we performed systematic analysis of X-linked gene copy number variations (CNVs) and Y chromosome haplogrouping in 447 idiopathic NOA patients and 485 healthy controls. Interestingly, the frequency of individuals with abnormal level copy of Variable charge, X-linked (VCX) was significantly different between cases and controls after multiple test correction (p = 5.10 × 10-5). To discriminate the effect of gain/loss copies in these genes, we analyzed the frequency of X-linked multi-copy genes in subjects among subdivided groups. Our results demonstrated that individuals with increased copy numbers of Nuclear RNA export factor 2 (NXF2) (p = 9.21 × 10-8) and VCX (p = 1.97 × 10-4) conferred the risk of NOA. In vitro analysis demonstrated that increasing copy number of VCX could upregulate the gene expression and regulate cell proliferation and apoptosis. Our study establishes a robust association between the VCX CNVs and NOA risk.

  4. Somatic Copy Number Alterations at Oncogenic Loci Show Diverse Correlations with Gene Expression

    Science.gov (United States)

    Roszik, Jason; Wu, Chang-Jiun; Siroy, Alan E.; Lazar, Alexander J.; Davies, Michael A.; Woodman, Scott E.; Kwong, Lawrence N.

    2016-01-01

    Somatic copy number alterations (SCNAs) affecting oncogenic drivers have a firmly established role in promoting cancer. However, no agreed-upon standard exists for calling locus-specific amplifications and deletions in each patient sample. Here, we report the correlative analysis of copy number amplitude and length with gene expression across 6,109 samples from The Cancer Genome Atlas (TCGA) dataset across 16 cancer types. Using specificity, sensitivity, and precision-based scores, we assigned optimized amplitude and length cutoffs for nine recurrent SCNAs affecting known oncogenic drivers, using mRNA expression as a functional readout. These cutoffs captured the majority of SCNA-driven, highly-expression-altered samples. The majority of oncogenes required only amplitude cutoffs, as high amplitude samples were almost invariably focal; however, CDKN2A and PTEN uniquely required both amplitude and length cutoffs as primary predictors. For PTEN, these extended to downstream AKT activation. In contrast, SCNA genes located peri-telomerically or in fragile sites showed poor expression-copy number correlations. Overall, our analyses identify optimized amplitude and length cutoffs as efficient predictors of gene expression changes for specific oncogenic SCNAs, yet warn against one-size-fits-all interpretations across all loci. Our results have implications for cancer data analyses and the clinic, where copy number and mutation data are increasingly used to personalize cancer therapy.

  5. Copy number polymorphism of the salivary amylase gene: implications in human nutrition research.

    Science.gov (United States)

    Santos, J L; Saus, E; Smalley, S V; Cataldo, L R; Alberti, G; Parada, J; Gratacòs, M; Estivill, X

    2012-01-01

    The salivary α-amylase is a calcium-binding enzyme that initiates starch digestion in the oral cavity. The α-amylase genes are located in a cluster on the chromosome that includes salivary amylase genes (AMY1), two pancreatic α-amylase genes (AMY2A and AMY2B) and a related pseudogene. The AMY1 genes show extensive copy number variation which is directly proportional to the salivary α-amylase content in saliva. The α-amylase amount in saliva is also influenced by other factors, such as hydration status, psychosocial stress level, and short-term dietary habits. It has been shown that the average copy number of AMY1 gene is higher in populations that evolved under high-starch diets versus low-starch diets, reflecting an intense positive selection imposed by diet on amylase copy number during evolution. In this context, a number of different aspects can be considered in evaluating the possible impact of copy number variation of the AMY1 gene on nutrition research, such as issues related to human diet gene evolution, action on starch digestion, effect on glycemic response after starch consumption, modulation of the action of α-amylases inhibitors, effect on taste perception and satiety, influence on psychosocial stress and relation to oral health.

  6. Genetic copy number variation and general cognitive ability.

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    Andrew K MacLeod

    Full Text Available Differences in genomic structure between individuals are ubiquitous features of human genetic variation. Specific copy number variants (CNVs have been associated with susceptibility to numerous complex psychiatric disorders, including attention-deficit-hyperactivity disorder, autism-spectrum disorders and schizophrenia. These disorders often display co-morbidity with low intelligence. Rare chromosomal deletions and duplications are associated with these disorders, so it has been suggested that these deletions or duplications may be associated with differences in intelligence. Here we investigate associations between large (≥500kb, rare (<1% population frequency CNVs and both fluid and crystallized intelligence in community-dwelling older people. We observe no significant associations between intelligence and total CNV load. Examining individual CNV regions previously implicated in neuropsychological disorders, we find suggestive evidence that CNV regions around SHANK3 are associated with fluid intelligence as derived from a battery of cognitive tests. This is the first study to examine the effects of rare CNVs as called by multiple algorithms on cognition in a large non-clinical sample, and finds no effects of such variants on general cognitive ability.

  7. Integrated analyses of copy number variations and gene expression in lung adenocarcinoma.

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    Tzu-Pin Lu

    Full Text Available Numerous efforts have been made to elucidate the etiology and improve the treatment of lung cancer, but the overall five-year survival rate is still only 15%. Identification of prognostic biomarkers for lung cancer using gene expression microarrays poses a major challenge in that very few overlapping genes have been reported among different studies. To address this issue, we have performed concurrent genome-wide analyses of copy number variation and gene expression to identify genes reproducibly associated with tumorigenesis and survival in non-smoking female lung adenocarcinoma. The genomic landscape of frequent copy number variable regions (CNVRs in at least 30% of samples was revealed, and their aberration patterns were highly similar to several studies reported previously. Further statistical analysis for genes located in the CNVRs identified 475 genes differentially expressed between tumor and normal tissues (p<10(-5. We demonstrated the reproducibility of these genes in another lung cancer study (p = 0.0034, Fisher's exact test, and showed the concordance between copy number variations and gene expression changes by elevated Pearson correlation coefficients. Pathway analysis revealed two major dysregulated functions in lung tumorigenesis: survival regulation via AKT signaling and cytoskeleton reorganization. Further validation of these enriched pathways using three independent cohorts demonstrated effective prediction of survival. In conclusion, by integrating gene expression profiles and copy number variations, we identified genes/pathways that may serve as prognostic biomarkers for lung tumorigenesis.

  8. Candidate predisposing germline copy number variants in early onset colorectal cancer patients.

    Science.gov (United States)

    Brea-Fernandez, A J; Fernandez-Rozadilla, C; Alvarez-Barona, M; Azuara, D; Ginesta, M M; Clofent, J; de Castro, L; Gonzalez, D; Andreu, M; Bessa, X; Llor, X; Xicola, R; Jover, R; Castells, A; Castellvi-Bel, S; Capella, G; Carracedo, A; Ruiz-Ponte, C

    2017-05-01

    A great proportion of the heritability of colorectal cancer (CRC) still remains unexplained, and rare variants, as well as copy number changes, have been proposed as potential candidates to explain the so-called 'missing heritability'. We aimed to identify rare high-to-moderately penetrant copy number variants (CNVs) in patients suspected of having hereditary CRC due to an early onset. We have selected for genome-wide copy number analysis, 27 MMR-proficient early onset CRC patients (1% in the in-house control CNV database (n = 629 healthy controls). Copy number assignment was checked by duplex real-time quantitative PCR or multiplex ligation probe amplification. Somatic mutation analysis in candidate genes included: loss of heterozygosity studies, point mutation screening, and methylation status of the promoter. We have identified two rare germline deletions involving the AK3 and SLIT2 genes in two patients. The search for a second somatic mutational event in the corresponding CRC tumors showed loss of heterozygosity in AK3, and promoter hypermethylation in SLIT2. Both genes have been previously related to colorectal carcinogenesis. These findings suggest that AK3 and SLIT2 may be potential candidates involved in genetic susceptibility to CRC.

  9. Selective constraint on copy number variation in human piwi-interacting RNA Loci.

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    David W Gould

    Full Text Available Piwi-interacting RNAs (piRNAs are a recently discovered class of small non-coding RNA found in animals. PiRNAs are primarily expressed in the germline where their best understood function is to repress transposable elements. Unlike previous studies that investigated the evolution of piRNA-generating loci at the level of nucleotide substitutions, here we studied the evolution of piRNA-generating loci at the level of copy number variation (i.e. duplications and deletions using genome-wide copy number variation data from three human populations. Our analysis shows that at the level of copy number variation there is strong selective constraint and a very high mutation rate in human piRNA-generating loci. Our results differ from a model of positive selection on copy number variation in piRNA-generating loci previously proposed in rodents. We discuss possible reasons for this difference based on the transposable element insertion histories in the rodent and primate lineages.

  10. Construction of plasmids with tunable copy numbers in Saccharomyces cerevisiae and their applications in pathway optimization and multiplex genome integration.

    Science.gov (United States)

    Lian, Jiazhang; Jin, Run; Zhao, Huimin

    2016-11-01

    The CEN/ARS-based low-copy plasmids and 2 μ-based high-copy plasmids have been broadly used for both fundamental studies and practical applications in Saccharomyces cerevisiae. However, the relative low copy numbers and narrow dynamic range limit their applications in many cases. In this study, the expression level of the selection marker proteins was engineered to increase the plasmid copy numbers. A series of plasmids with step-wise increased copy numbers were constructed. The copy number of the plasmids with engineered dominant markers (5-100 copies per cell) showed a positive correlation with the concentration of antibiotics supplemented to the growth media. Based on this finding, we developed a simple yet highly efficient strategy, named Pathway Optimization by Tuning Antibiotic Concentrations (POTAC) to rapidly balance the flux of multi-gene pathways at the DNA level in S. cerevisiae. As proof of concept, POTAC was used to optimize the lycopene and n-butanol biosynthetic pathways, increasing the production of lycopene and n-butanol by 10- and 100-fold, respectively. Additionally, multiplex genome integration with controllable copy numbers was attempted by combining the engineered dominant markers with the CRISPR/Cas9 system. Biotechnol. Bioeng. 2016;113: 2462-2473. © 2016 Wiley Periodicals, Inc.

  11. DUF1220-domain copy number implicated in human brain-size pathology and evolution.

    Science.gov (United States)

    Dumas, Laura J; O'Bleness, Majesta S; Davis, Jonathan M; Dickens, C Michael; Anderson, Nathan; Keeney, J G; Jackson, Jay; Sikela, Megan; Raznahan, Armin; Giedd, Jay; Rapoport, Judith; Nagamani, Sandesh S C; Erez, Ayelet; Brunetti-Pierri, Nicola; Sugalski, Rachel; Lupski, James R; Fingerlin, Tasha; Cheung, Sau Wai; Sikela, James M

    2012-09-07

    DUF1220 domains show the largest human-lineage-specific increase in copy number of any protein-coding region in the human genome and map primarily to 1q21, where deletions and reciprocal duplications have been associated with microcephaly and macrocephaly, respectively. Given these findings and the high correlation between DUF1220 copy number and brain size across primate lineages (R(2) = 0.98; p = 1.8 × 10(-6)), DUF1220 sequences represent plausible candidates for underlying 1q21-associated brain-size pathologies. To investigate this possibility, we used specialized bioinformatics tools developed for scoring highly duplicated DUF1220 sequences to implement targeted 1q21 array comparative genomic hybridization on individuals (n = 42) with 1q21-associated microcephaly and macrocephaly. We show that of all the 1q21 genes examined (n = 53), DUF1220 copy number shows the strongest association with brain size among individuals with 1q21-associated microcephaly, particularly with respect to the three evolutionarily conserved DUF1220 clades CON1(p = 0.0079), CON2 (p = 0.0134), and CON3 (p = 0.0116). Interestingly, all 1q21 DUF1220-encoding genes belonging to the NBPF family show significant correlations with frontal-occipital-circumference Z scores in the deletion group. In a similar survey of a nondisease population, we show that DUF1220 copy number exhibits the strongest correlation with brain gray-matter volume (CON1, p = 0.0246; and CON2, p = 0.0334). Notably, only DUF1220 sequences are consistently significant in both disease and nondisease populations. Taken together, these data strongly implicate the loss of DUF1220 copy number in the etiology of 1q21-associated microcephaly and support the view that DUF1220 domains function as general effectors of evolutionary, pathological, and normal variation in brain size. Copyright © 2012 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  12. Copy number variations in three children with sudden infant death.

    Science.gov (United States)

    Toruner, G A; Kurvathi, R; Sugalski, R; Shulman, L; Twersky, S; Pearson, P G; Tozzi, R; Schwalb, M N; Wallerstein, R

    2009-07-01

    Sudden death of an infant is a devastating event that needs an explanation. When an explanation cannot be found, the case is labeled as sudden infant death syndrome or unclassified sudden infant death. The influence of genetic factors has been recognized for sudden infant death, but copy number variations (CNVs) as potential risk factors have not been evaluated yet. Twenty-seven families were enrolled in this study. The tissue specimens from deceased children were obtained and array-based comparative genomic hybridization (array-CGH) experiments were performed on the genomic DNA isolated from these specimens using Agilent Technologies Custom 4 x 44K arrays. Quantitative polymerase chain reaction experiments were performed to confirm the overlapping duplication and deletion region in two different cases. A de novo CNV is detected in 3 of 27 cases (11%). In case 1, an approximately 3-Mb (chr 8: 143,211,215-qter) duplication on 8q24.3-qter and a 4.4-Mb deletion on the 22q13.3-qter (chr 22: 45,047,068-qter) were detected. Subtelomeric chromosome analysis of the father and the surviving sibling of case 1 showed a balanced reciprocal translocation, 46,XY,t(8;22)(q24.3;q13.3). A 240-kb (chr 6: 26,139,810-26,380,787) duplication and a 1.9-Mb deletion (chr 6: 26,085,971-27,966,150) at chromosome 6p22 were found in cases 2 and 3, respectively. Array-CGH and conventional cytogenetic studies did not reveal the observed CNVs in the parents and the siblings of cases 2 and 3. The detected CNVs in cases 2 and 3 encompassed several genes including the major histone cluster genes. Array-CGH analysis may be beneficial during the investigations after sudden infant death.

  13. Genomic DNA copy-number alterations of the let-7 family in human cancers.

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    Yanling Wang

    Full Text Available In human cancer, expression of the let-7 family is significantly reduced, and this is associated with shorter survival times in patients. However, the mechanisms leading to let-7 downregulation in cancer are still largely unclear. Since an alteration in copy-number is one of the causes of gene deregulation in cancer, we examined copy number alterations of the let-7 family in 2,969 cancer specimens from a high-resolution SNP array dataset. We found that there was a reduction in the copy number of let-7 genes in a cancer-type specific manner. Importantly, focal deletion of four let-7 family members was found in three cancer types: medulloblastoma (let-7a-2 and let-7e, breast cancer (let-7a-2, and ovarian cancer (let-7a-3/let-7b. For example, the genomic locus harboring let-7a-3/let-7b was deleted in 44% of the specimens from ovarian cancer patients. We also found a positive correlation between the copy number of let-7b and mature let-7b expression in ovarian cancer. Finally, we showed that restoration of let-7b expression dramatically reduced ovarian tumor growth in vitro and in vivo. Our results indicate that copy number deletion is an important mechanism leading to the downregulation of expression of specific let-7 family members in medulloblastoma, breast, and ovarian cancers. Restoration of let-7 expression in tumor cells could provide a novel therapeutic strategy for the treatment of cancer.

  14. Short copy number variations potentially associated with tonic immobility responses in newly hatched chicks.

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    Hideaki Abe

    Full Text Available INTRODUCTION: Tonic immobility (TI is fear-induced freezing that animals may undergo when confronted by a threat. It is principally observed in prey species as defence mechanisms. In our preliminary research, we detected large inter-individual variations in the frequency and duration of freezing behavior among newly hatched domestic chicks (Gallus gallus. In this study we aim to identify the copy number variations (CNVs in the genome of chicks as genetic candidates that underlie the behavioral plasticity to fearful stimuli. METHODS: A total of 110 domestic chicks were used for an association study between TI responses and copy number polymorphisms. Array comparative genomic hybridization (aCGH was conducted between chicks with high and low TI scores using an Agilent 4 × 180 custom microarray. We specifically focused on 3 genomic regions (>60 Mb of chromosome 1 where previous quantitative trait loci (QTL analysis showed significant F-values for fearful responses. RESULTS: ACGH successfully detected short CNVs within the regions overlapping 3 QTL peaks. Eleven of these identified loci were validated by real-time quantitative polymerase chain reaction (qPCR as copy number polymorphisms. Although there wkas no significant p value in the correlation analysis between TI scores and the relative copy number within each breed, several CNV loci showed significant differences in the relative copy number between 2 breeds of chicken (White Leghorn and Nagoya which had different quantitative characteristics of fear-induced responses. CONCLUSION: Our data shows the potential CNVs that may be responsible for innate fear response in domestic chicks.

  15. High-resolution analysis of DNA copy number alterations in rectal cancer. Correlation with metastasis, survival, and mRNA expression

    Energy Technology Data Exchange (ETDEWEB)

    Doyen, Jerome; Gerard, Jean-Pierre [Centre Antoine-Lacassagne, Department of Radiation Oncology, Nice (France); University of Nice Sophia-Antipolis, Nice (France); Letouze, Eric; Marisa, Laetitia; Reynies, Aurelien de [Ligue Nationale Contre Le Cancer, Programme Cartes d' Identite des Tumeurs, Paris (France); Milano, Gerard; Etienne-Grimaldi, Marie-Christine [University of Nice Sophia-Antipolis, Nice (France); Centre Antoine-Lacassagne, Oncopharmacology Unit, Nice (France); Olschwang, Sylviane [INSERM U1068, Marseille (France); Gaedcke, Jochen; Ghadimi, Michael [University Medical Center Goettingen, Department of General and Visceral Surgery, Goettingen (Germany)

    2014-11-15

    This study aimed to determine the candidate genes and chromosomal imbalances capable of predicting occurrences of metastasis in patients with rectal cancer. Fresh frozen tumor tissues from 80 patients with rectal cancer were prospectively collected and analyzed using Affymetrix HG-U133 Plus 2.0 gene expression arrays and high-resolution Illumina single-nucleotide polymorphism (SNP) arrays. Endpoints of the study were metastasis-free survival (MFS) and cancer-specific survival (CSS). The median follow-up was 102 months (1-146). Deletions of 8p and 1p36-35 correlated with worse MFS (p = 0.005 and p = 0.01, respectively) and CSS (p = 0.001 and p = 0.01, respectively). Multivariate analysis identified 8p deletion as an independent prognostic factor for MFS (p = 0.04) and CSS (p = 0.003); 97 genes located on the 8p chromosome were significantly underexpressed in tumors with 8p deletion. This study shows for the first time in rectal cancer an independent correlation of 8p deletion with MFS and CSS and highlights potential new tumor suppressor genes. (orig.) [German] Diese Studie zielt darauf ab, Kandidatengene und chromosomale Ungleichgewichte vorherzusagen und das Auftreten von Metastasen bei Rektumkarzinompatienten zu bestimmen. Frisch gefrorenes Tumorgewebe von 80 Patienten mit Rektumkarzinom wurde prospektiv erfasst und mit Affymetrix-(HG-U133-Plus-2.0)-Genexpressionsarrays und hochaufloesenden Illumina-Single-Nukleotid-Polymorphismus-(SNP-)Arrays analysiert. Endpunkte der Studie waren fernmetastasenfreies Ueberleben (MFU) und krebsspezifisches Ueberleben (KSU). Die mediane Nachbeobachtungszeit betrug 102 Monate (1-146 Monate). Die Deletionen von 8p und 1p36-35 waren mit schlechterem MFU (jeweils p = 0,005 und p = 0,01) und KSU (jeweils p = 0,001 und p = 0,01) korreliert. Die multivariate Analyse identifizierte - 8p als unabhaengigen prognostischen Faktor fuer MFU (p = 0,04) und KSU (p = 0,003). In Tumoren mit einer 8p-Deletion waren 97 Gene auf Chromosom 8p

  16. Copy-number variation and false positive prenatal aneuploidy screening results.

    Science.gov (United States)

    Snyder, Matthew W; Simmons, LaVone E; Kitzman, Jacob O; Coe, Bradley P; Henson, Jessica M; Daza, Riza M; Eichler, Evan E; Shendure, Jay; Gammill, Hilary S

    2015-04-23

    Investigations of noninvasive prenatal screening for aneuploidy by analysis of circulating cell-free DNA (cfDNA) have shown high sensitivity and specificity in both high-risk and low-risk cohorts. However, the overall low incidence of aneuploidy limits the positive predictive value of these tests. Currently, the causes of false positive results are poorly understood. We investigated four pregnancies with discordant prenatal test results and found in two cases that maternal duplications on chromosome 18 were the likely cause of the discordant results. Modeling based on population-level copy-number variation supports the possibility that some false positive results of noninvasive prenatal screening may be attributable to large maternal copy-number variants. (Funded by the National Institutes of Health and others.).

  17. Detection of genomic copy number changes in patients with idiopathic mental retardation by high-resolution X-array-CGH: important role for increased gene dosage of XLMR genes.

    Science.gov (United States)

    Froyen, Guy; Van Esch, Hilde; Bauters, Marijke; Hollanders, Karen; Frints, Suzanna G M; Vermeesch, Joris R; Devriendt, Koen; Fryns, Jean-Pierre; Marynen, Peter

    2007-10-01

    A tiling X-chromosome-specific genomic array with a theoretical resolution of 80 kb was developed to screen patients with idiopathic mental retardation (MR) for submicroscopic copy number differences. Four patients with aberrations previously detected at lower resolution were first analyzed. This facilitated delineation of the location and extent of the aberration at high resolution and subsequently, more precise genotype-phenotype analyses. A cohort of 108 patients was screened, 57 of which were suspected of X-linked mental retardation (XLMR), 26 were probands of brother pairs, and 25 were sporadic cases. A total of 15 copy number changes in 14 patients (13%) were detected, which included two deletions and 13 duplications ranging from 0.1 to 2.7 Mb. The aberrations are associated with the phenotype in five patients (4.6%), based on the following criteria: de novo aberration; involvement of a known or candidate X-linked nonsyndromic(syndromic) MR (MRX(S)) gene; segregation with the disease in the family; absence in control individuals; and skewed X-inactivation in carrier females. These include deletions that contain the MRX(S) genes CDKL5, OPHN1, and CASK, and duplications harboring CDKL5, NXF5, MECP2, and GDI1. In addition, seven imbalances were apparent novel polymorphic regions because they do not fulfill the proposed criteria. Taken together, our data strongly suggest that not only deletions but also duplications on the X chromosome contribute to the phenotype more often than expected, supporting the increased gene dosage mechanism for deregulation of normal cognitive development.

  18. Copy number variation in the genomes of twelve natural isolates of Caenorhabditis elegans

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    Flibotte Stephane

    2010-01-01

    Full Text Available Abstract Background Copy number variation is an important component of genetic variation in higher eukaryotes. The extent of natural copy number variation in C. elegans is unknown outside of 2 highly divergent wild isolates and the canonical N2 Bristol strain. Results We have used array comparative genomic hybridization (aCGH to detect copy number variation in the genomes of 12 natural isolates of Caenorhabditis elegans. Deletions relative to the canonical N2 strain are more common in these isolates than duplications, and indels are enriched in multigene families on the autosome arms. Among the strains in our study, the Hawaiian and Madeiran strains (CB4856 and JU258 carry the largest number of deletions, followed by the Vancouver strain (KR314. Overall we detected 510 different deletions affecting 1136 genes, or over 5% of the genes in the canonical N2 genome. The indels we identified had a median length of 2.7 kb. Since many deletions are found in multiple isolates, deletion loci were used as markers to derive an unrooted tree to estimate genetic relatedness among the strains. Conclusion Copy number variation is extensive in C. elegans, affecting over 5% of the genes in the genome. The deletions we have detected in natural isolates of C. elegans contribute significantly to the number of deletion alleles available to researchers. The relationships between strains are complex and different regions of the genome possess different genealogies due to recombination throughout the natural history of the species, which may not be apparent in studies utilizing smaller numbers of genetic markers.

  19. Macronuclear Actin copy number variations in single cells of different Pseudokeronopsis (Alveolata, Ciliophora) populations.

    Science.gov (United States)

    Huang, Lijuan; Lu, Xuefen; Zhu, Changyu; Lin, Xiaofeng; Yi, Zhenzhen

    2017-06-01

    Macronuclear chromosomes of ciliates, especially those of Spirotrichea, Armophorea and Phyllopharyngea, are extensively fragmented and their copy numbers vary significantly. A recent study suggested that parental RNA molecules regulate macronuclear copy number in offspring cells after conjugation. However, variations in patterns of macronuclear copy number during vegetative growth are not clear. Previous studies have reported macronuclear copy numbers of population averages, potentially masking individual variation. In the present investigation, we studied copy number variations among closely related species of Pseudokeronopsis and among individual cells during vegetative growth. We found that macronuclear copy numbers of Actin I, II in our Pseudokeronopsis populations are in the same range as in other spirotrichean species, but no close relationship is detected among morphologically related Pseudokeronopsis species. Copy numbers of three cells within each Pseudokeronopsis population range from 1.01 to 4.55 fold, suggesting that stochastic influences copy number during vegetative growth. Furthermore, the absence of a relationship between macronuclear copy numbers of Actin I and Actin II within Pseudokeronopsis is consistent with the fact that these genes are located on different gene-sized macronuclear chromosomes. Additionally, Actin II might have disappeared in P. carnea during evolution within the Actin gene family. Copyright © 2017 Elsevier GmbH. All rights reserved.

  20. Mitochondrial DNA copy number in whole blood and glioma risk: A case control study.

    Science.gov (United States)

    Shen, Jie; Song, Renduo; Lu, Zhimin; Zhao, Hua

    2016-12-01

    Alterations in mitochondrial DNA (mtDNA) copy number are observed in human gliomas. However, whether variations in mtDNA copy number in whole blood play any role in glioma carcinogenesis is still largely unknown. In current study with 395 glioma patients and 425 healthy controls, we intended to investigate the association between mtDNA copy number in whole blood and glioma risk. Overall, we found that levels of mtDNA copy number were significantly higher in glioma cases than healthy controls (mean: 1.48 vs. 1.32, P copy number were inversely correlated with age (P copy number than their counterparts (P = 0.02, P copy number levels were associated with a 1.63-fold increased risk of glioma (adjusted odds ratio (OR) = 1.63, 95% confidence interval (CI) = 1.23-2.14). In further quartile analysis, study subjects who had highest levels of mtNDA copy number had 1.75-fold increased risk of gliomas (adjOR = 1.75, 95%CI = 1.18-2.61). In brief, our findings support the role of mtDNA copy number in the glioma carcinogenesis. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  1. Determination of beta-defensin genomic copy number in different populations

    DEFF Research Database (Denmark)

    Fode, Peder; Jespersgaard, Cathrine; Hardwick, Robert J

    2011-01-01

    There have been conflicting reports in the literature on association of gene copy number with disease, including CCL3L1 and HIV susceptibility, and ß-defensins and Crohn's disease. Quantification of precise gene copy numbers is important in order to define any association of gene copy number...... with disease. At present, real-time quantitative PCR (QPCR) is the most commonly used method to determine gene copy number, however the Paralogue Ratio Test (PRT) is being used in more and more laboratories....

  2. A robust penalized method for the analysis of noisy DNA copy number data

    Directory of Open Access Journals (Sweden)

    Huang Jian

    2010-09-01

    Full Text Available Abstract Background Deletions and amplifications of the human genomic DNA copy number are the causes of numerous diseases, such as, various forms of cancer. Therefore, the detection of DNA copy number variations (CNV is important in understanding the genetic basis of many diseases. Various techniques and platforms have been developed for genome-wide analysis of DNA copy number, such as, array-based comparative genomic hybridization (aCGH and high-resolution mapping with high-density tiling oligonucleotide arrays. Since complicated biological and experimental processes are often associated with these platforms, data can be potentially contaminated by outliers. Results We propose a penalized LAD regression model with the adaptive fused lasso penalty for detecting CNV. This method contains robust properties and incorporates both the spatial dependence and sparsity of CNV into the analysis. Our simulation studies and real data analysis indicate that the proposed method can correctly detect the numbers and locations of the true breakpoints while appropriately controlling the false positives. Conclusions The proposed method has three advantages for detecting CNV change points: it contains robustness properties; incorporates both spatial dependence and sparsity; and estimates the true values at each marker accurately.

  3. The Orphan Gene dauerless Regulates Dauer Development and Intraspecific Competition in Nematodes by Copy Number Variation.

    Science.gov (United States)

    Mayer, Melanie G; Rödelsperger, Christian; Witte, Hanh; Riebesell, Metta; Sommer, Ralf J

    2015-06-01

    Many nematodes form dauer larvae when exposed to unfavorable conditions, representing an example of phenotypic plasticity and a major survival and dispersal strategy. In Caenorhabditis elegans, the regulation of dauer induction is a model for pheromone, insulin, and steroid-hormone signaling. Recent studies in Pristionchus pacificus revealed substantial natural variation in various aspects of dauer development, i.e. pheromone production and sensing and dauer longevity and fitness. One intriguing example is a strain from Ohio, having extremely long-lived dauers associated with very high fitness and often forming the most dauers in response to other strains' pheromones, including the reference strain from California. While such examples have been suggested to represent intraspecific competition among strains, the molecular mechanisms underlying these dauer-associated patterns are currently unknown. We generated recombinant-inbred-lines between the Californian and Ohioan strains and used quantitative-trait-loci analysis to investigate the molecular mechanism determining natural variation in dauer development. Surprisingly, we discovered that the orphan gene dauerless controls dauer formation by copy number variation. The Ohioan strain has one dauerless copy causing high dauer formation, whereas the Californian strain has two copies, resulting in strongly reduced dauer formation. Transgenic animals expressing multiple copies do not form dauers. dauerless is exclusively expressed in CAN neurons, and both CAN ablation and dauerless mutations increase dauer formation. Strikingly, dauerless underwent several duplications and acts in parallel or downstream of steroid-hormone signaling but upstream of the nuclear-hormone-receptor daf-12. We identified the novel or fast-evolving gene dauerless as inhibitor of dauer development. Our findings reveal the importance of gene duplications and copy number variations for orphan gene function and suggest daf-12 as major target for

  4. The Orphan Gene dauerless Regulates Dauer Development and Intraspecific Competition in Nematodes by Copy Number Variation.

    Directory of Open Access Journals (Sweden)

    Melanie G Mayer

    2015-06-01

    Full Text Available Many nematodes form dauer larvae when exposed to unfavorable conditions, representing an example of phenotypic plasticity and a major survival and dispersal strategy. In Caenorhabditis elegans, the regulation of dauer induction is a model for pheromone, insulin, and steroid-hormone signaling. Recent studies in Pristionchus pacificus revealed substantial natural variation in various aspects of dauer development, i.e. pheromone production and sensing and dauer longevity and fitness. One intriguing example is a strain from Ohio, having extremely long-lived dauers associated with very high fitness and often forming the most dauers in response to other strains' pheromones, including the reference strain from California. While such examples have been suggested to represent intraspecific competition among strains, the molecular mechanisms underlying these dauer-associated patterns are currently unknown. We generated recombinant-inbred-lines between the Californian and Ohioan strains and used quantitative-trait-loci analysis to investigate the molecular mechanism determining natural variation in dauer development. Surprisingly, we discovered that the orphan gene dauerless controls dauer formation by copy number variation. The Ohioan strain has one dauerless copy causing high dauer formation, whereas the Californian strain has two copies, resulting in strongly reduced dauer formation. Transgenic animals expressing multiple copies do not form dauers. dauerless is exclusively expressed in CAN neurons, and both CAN ablation and dauerless mutations increase dauer formation. Strikingly, dauerless underwent several duplications and acts in parallel or downstream of steroid-hormone signaling but upstream of the nuclear-hormone-receptor daf-12. We identified the novel or fast-evolving gene dauerless as inhibitor of dauer development. Our findings reveal the importance of gene duplications and copy number variations for orphan gene function and suggest daf-12 as

  5. miRNA Copy Number Variants Confer Susceptibility to Acute Anterior Uveitis With or Without Ankylosing Spondylitis.

    Science.gov (United States)

    Yang, Lu; Du, Liping; Yue, Yingying; Huang, Yike; Zhou, Qingyun; Cao, Shuang; Qi, Jian; Liang, Liang; Wu, Lili; Wang, Chaokui; Ye, Zi; Tian, Yuan; Kijlstra, Aize; Hou, Shengping; Yang, Peizeng

    2017-04-01

    To investigate the association of microRNA (miRNA) copy number variants (CNVs) with acute anterior uveitis (AAU) with or without ankylosing spondylitis (AS) and to assess underlying disease mechanisms. This study included 768 patients with AAU+AS+ or AAU+AS- and 660 controls from a Chinese Han population. Genotyping of CNVs was performed by TaqMan PCR. The expression of miRNAs, transfection efficiency of miR-9-3, and cytokine production were measured by real-time PCR, flow cytometry, or ELISA. The frequency of low copy numbers of miR-143, miR-146a, miR-9-3, and miR-205 and of high copy numbers of miR-301a and miR-23a was increased in patients with AAU+AS+ (P = 3.725 × 10-5 to 8.033 × 10-9). Additionally, the frequency of a low copy number of miR-146a and a high copy number of miR-23a and miR-205 was significantly increased in AAU+AS- patients (P = 0.002-0.001). The frequency of low copy number of miR-205 was increased in AAU+AS+ compared with AAU+AS- (P = 0.001). The mRNA expression of miR-9-3 was significantly decreased in patients with AAU+AS+ compared with controls and positively associated with its copy number. Additionally, the production of IL-1β and IL-6 was shown to be regulated by miR-9-3 in human primary retinal pigment epithelial cells. Low gene copy numbers of miR-143, miR-146a, miR-9-3, miR-205 and high gene copy numbers of miR-301a and miR-23a were associated with susceptibility to AAU+AS+. A low copy number of miR-146a and a high copy number of miR-23a and miR-205 were associated with AAU+AS-.

  6. Copy number analysis identifies novel interactions between genomic loci in ovarian cancer.

    Directory of Open Access Journals (Sweden)

    Kylie L Gorringe

    Full Text Available Ovarian cancer is a heterogeneous disease displaying complex genomic alterations, and consequently, it has been difficult to determine the most relevant copy number alterations with the scale of studies to date. We obtained genome-wide copy number alteration (CNA data from four different SNP array platforms, with a final data set of 398 ovarian tumours, mostly of the serous histological subtype. Frequent CNA aberrations targeted many thousands of genes. However, high-level amplicons and homozygous deletions enabled filtering of this list to the most relevant. The large data set enabled refinement of minimal regions and identification of rare amplicons such as at 1p34 and 20q11. We performed a novel co-occurrence analysis to assess cooperation and exclusivity of CNAs and analysed their relationship to patient outcome. Positive associations were identified between gains on 19 and 20q, gain of 20q and loss of X, and between several regions of loss, particularly 17q. We found weak correlations of CNA at genomic loci such as 19q12 with clinical outcome. We also assessed genomic instability measures and found a correlation of the number of higher amplitude gains with poorer overall survival. By assembling the largest collection of ovarian copy number data to date, we have been able to identify the most frequent aberrations and their interactions.

  7. Copy number analysis identifies novel interactions between genomic loci in ovarian cancer.

    Science.gov (United States)

    Gorringe, Kylie L; George, Joshy; Anglesio, Michael S; Ramakrishna, Manasa; Etemadmoghadam, Dariush; Cowin, Prue; Sridhar, Anita; Williams, Louise H; Boyle, Samantha E; Yanaihara, Nozomu; Okamoto, Aikou; Urashima, Mitsuyoshi; Smyth, Gordon K; Campbell, Ian G; Bowtell, David D L

    2010-09-10

    Ovarian cancer is a heterogeneous disease displaying complex genomic alterations, and consequently, it has been difficult to determine the most relevant copy number alterations with the scale of studies to date. We obtained genome-wide copy number alteration (CNA) data from four different SNP array platforms, with a final data set of 398 ovarian tumours, mostly of the serous histological subtype. Frequent CNA aberrations targeted many thousands of genes. However, high-level amplicons and homozygous deletions enabled filtering of this list to the most relevant. The large data set enabled refinement of minimal regions and identification of rare amplicons such as at 1p34 and 20q11. We performed a novel co-occurrence analysis to assess cooperation and exclusivity of CNAs and analysed their relationship to patient outcome. Positive associations were identified between gains on 19 and 20q, gain of 20q and loss of X, and between several regions of loss, particularly 17q. We found weak correlations of CNA at genomic loci such as 19q12 with clinical outcome. We also assessed genomic instability measures and found a correlation of the number of higher amplitude gains with poorer overall survival. By assembling the largest collection of ovarian copy number data to date, we have been able to identify the most frequent aberrations and their interactions.

  8. Gene expression profiling and gene copy-number changes in malignant mesothelioma cell lines.

    Science.gov (United States)

    Zanazzi, Claudia; Hersmus, Remko; Veltman, Imke M; Gillis, Ad J M; van Drunen, Ellen; Beverloo, H Berna; Hegmans, Joost P J J; Verweij, Marielle; Lambrecht, Bart N; Oosterhuis, J Wolter; Looijenga, Leendert H J

    2007-10-01

    Malignant mesothelioma (MM) is an asbestos-induced tumor that acquires aneuploid DNA content during the tumorigenic process. We used instable MM cell lines as an in vitro model to study the impact of DNA copy-number changes on gene expression profiling, in the course of their chromosomal redistribution process. Two MM cell lines, PMR-MM2 (early passages of in vitro culture) and PMR-MM7 (both early and late passages of in vitro culture), were cytogenetically characterized. Genomic gains and losses were precisely defined using microarray-based comparative genomic hybridization (array-CGH), and minimal overlapping analysis led to the identification of the common unbalanced genomic regions. Using the U133Plus 2.0 Affymetrix gene chip array, we analyzed PMR-MM7 early and late passages for genome-wide gene expression, and correlated the differentially expressed genes with copy-number changes. The presence of a high number of genetic imbalances occurring from early to late culture steps reflected the tendency of MM cells toward genomic instability. The selection of specific chromosomal abnormalities observed during subsequent cultures demonstrated the spontaneous evolution of the cancer cells in an in vitro environment. MM cell lines were characterized by copy-number changes associated with the TP53 apoptotic pathway already present at the first steps of in vitro culture. Prolonged culture led to acquisition of additional chromosomal copy-number changes associated with dysregulation of genes involved in cell adhesion, regulation of mitotic cell cycle, signal transduction, carbohydrate metabolism, motor activity, glycosaminoglycan biosynthesis, protein binding activity, lipid transport, ATP synthesis, and methyltransferase activity.

  9. Low copy number of the salivary amylase gene predisposes to obesity.

    Science.gov (United States)

    Falchi, Mario; El-Sayed Moustafa, Julia Sarah; Takousis, Petros; Pesce, Francesco; Bonnefond, Amélie; Andersson-Assarsson, Johanna C; Sudmant, Peter H; Dorajoo, Rajkumar; Al-Shafai, Mashael Nedham; Bottolo, Leonardo; Ozdemir, Erdal; So, Hon-Cheong; Davies, Robert W; Patrice, Alexandre; Dent, Robert; Mangino, Massimo; Hysi, Pirro G; Dechaume, Aurélie; Huyvaert, Marlène; Skinner, Jane; Pigeyre, Marie; Caiazzo, Robert; Raverdy, Violeta; Vaillant, Emmanuel; Field, Sarah; Balkau, Beverley; Marre, Michel; Visvikis-Siest, Sophie; Weill, Jacques; Poulain-Godefroy, Odile; Jacobson, Peter; Sjostrom, Lars; Hammond, Christopher J; Deloukas, Panos; Sham, Pak Chung; McPherson, Ruth; Lee, Jeannette; Tai, E Shyong; Sladek, Robert; Carlsson, Lena M S; Walley, Andrew; Eichler, Evan E; Pattou, Francois; Spector, Timothy D; Froguel, Philippe

    2014-05-01

    Common multi-allelic copy number variants (CNVs) appear enriched for phenotypic associations compared to their biallelic counterparts. Here we investigated the influence of gene dosage effects on adiposity through a CNV association study of gene expression levels in adipose tissue. We identified significant association of a multi-allelic CNV encompassing the salivary amylase gene (AMY1) with body mass index (BMI) and obesity, and we replicated this finding in 6,200 subjects. Increased AMY1 copy number was positively associated with both amylase gene expression (P = 2.31 × 10(-14)) and serum enzyme levels (P copy number was associated with increased BMI (change in BMI per estimated copy = -0.15 (0.02) kg/m(2); P = 6.93 × 10(-10)) and obesity risk (odds ratio (OR) per estimated copy = 1.19, 95% confidence interval (CI) = 1.13-1.26; P = 1.46 × 10(-10)). The OR value of 1.19 per copy of AMY1 translates into about an eightfold difference in risk of obesity between subjects in the top (copy number > 9) and bottom (copy number copy number distribution. Our study provides a first genetic link between carbohydrate metabolism and BMI and demonstrates the power of integrated genomic approaches beyond genome-wide association studies.

  10. Cheek swabs, SNP chips, and CNVs: Assessing the quality of copy number variant calls generated with subject-collected mail-in buccal brush DNA samples on a high-density genotyping microarray

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    Erickson Stephen W

    2012-06-01

    Full Text Available Abstract Background Multiple investigators have established the feasibility of using buccal brush samples to genotype single nucleotide polymorphisms (SNPs with high-density genome-wide microarrays, but there is currently no consensus on the accuracy of copy number variants (CNVs inferred from these data. Regardless of the source of DNA, it is more difficult to detect CNVs than to genotype SNPs using these microarrays, and it therefore remains an open question whether buccal brush samples provide enough high-quality DNA for this purpose. Methods To demonstrate the quality of CNV calls generated from DNA extracted from buccal samples, compared to calls generated from blood samples, we evaluated the concordance of calls from individuals who provided both sample types. The Illumina Human660W-Quad BeadChip was used to determine SNPs and CNVs of 39 Arkansas participants in the National Birth Defects Prevention Study (NBDPS, including 16 mother-infant dyads, who provided both whole blood and buccal brush DNA samples. Results We observed a 99.9% concordance rate of SNP calls in the 39 blood–buccal pairs. From the same dataset, we performed a similar analysis of CNVs. Each of the 78 samples was independently segmented into regions of like copy number using the Optimal Segmentation algorithm of Golden Helix SNP & Variation Suite 7. Across 640,663 loci on 22 autosomal chromosomes, segment-mean log R ratios had an average correlation of 0.899 between blood-buccal pairs of samples from the same individual, while the average correlation between all possible blood-buccal pairs of samples from unrelated individuals was 0.318. An independent analysis using the QuantiSNP algorithm produced average correlations of 0.943 between blood-buccal pairs from the same individual versus 0.332 between samples from unrelated individuals. Segment-mean log R ratios had an average correlation of 0.539 between mother-offspring dyads of buccal samples, which was not

  11. 5 CFR 2429.25 - Number of copies and paper size.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Number of copies and paper size. 2429.25... Requirements § 2429.25 Number of copies and paper size. Unless otherwise provided by the Authority or the... the exception of any prescribed forms, any document or paper filed with the Authority, General Counsel...

  12. Reduced purifying selection prevails over positive selection in human copy number variant evolution.

    NARCIS (Netherlands)

    Nguyen, D.Q.; Webber, C.; Hehir-Kwa, J.; Pfundt, R.; Veltman, J.A.; Ponting, C.P.

    2008-01-01

    Copy number variation is a dominant contributor to genomic variation and may frequently underlie an individual's variable susceptibilities to disease. Here we question our previous proposition that copy number variants (CNVs) are often retained in the human population because of their adaptive

  13. Copy number variation in Fayoumi and Leghorn chickens analyzed using array comparative genomic hybridization

    NARCIS (Netherlands)

    Abernathy, J.; Li, X.; Jia, X.; Chou, W.; Lamont, S.J.; Crooijmans, R.P.M.A.; Zhou, H.

    2014-01-01

    Copy number variation refers to regions along chromosomes that harbor a type of structural variation, such as duplications or deletions. Copy number variants (CNVs) play a role in many important traits as well as in genetic diversity. Previous analyses of chickens using array comparative genomic hyb

  14. 10 CFR 205.307 - Form and style; number of copies

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Form and style; number of copies 205.307 Section 205.307 Energy DEPARTMENT OF ENERGY OIL ADMINISTRATIVE PROCEDURES AND SANCTIONS Electric Power System Permits and... Electric Energy to A Foreign Country § 205.307 Form and style; number of copies An original and...

  15. Familial longevity study reveals a significant association of mitochondrial DNA copy number between centenarians and their offspring.

    Science.gov (United States)

    He, Yong-Han; Chen, Xiao-Qiong; Yan, Dong-Jing; Xiao, Fu-Hui; Lin, Rong; Liao, Xiao-Ping; Liu, Yao-Wen; Pu, Shao-Yan; Yu, Qin; Sun, Hong-Peng; Jiang, Jian-Jun; Cai, Wang-Wei; Kong, Qing-Peng

    2016-11-01

    Reduced mitochondrial function is an important cause of aging and age-related diseases. We previously revealed a relatively higher level of mitochondrial DNA (mtDNA) content in centenarians. However, it is still unknown whether such an mtDNA content pattern of centenarians could be passed on to their offspring and how it was regulated. To address these issues, we recruited 60 longevity families consisting of 206 family members (cohort 1) and explored their mtDNA copy number. The results showed that the first generation of the offspring (F1 offspring) had a higher level of mtDNA copy number than their spouses (p copy number in centenarians with that in F1 offspring (r = 0.54, p = 0.0008) but not with that in F1 spouses. These results were replicated in another independent cohort consisting of 153 subjects (cohort 2). RNA sequencing analysis suggests that the single-stranded DNA-binding protein 4 was significantly associated with mtDNA copy number and was highly expressed in centenarians as well as F1 offspring versus the F1 spouses, thus likely regulates the mtDNA copy number in the long-lived family members. In conclusion, our results suggest that the pattern of high mtDNA copy number is likely inheritable, which may act as a favorable factor to familial longevity through assuring adequate energy supply. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Copy-number and gene dependency analysis reveals partial copy loss of wild-type SF3B1 as a novel cancer vulnerability. | Office of Cancer Genomics

    Science.gov (United States)

    Genomic instability is a hallmark of human cancer, and results in widespread somatic copy number alterations. We used a genome-scale shRNA viability screen in human cancer cell lines to systematically identify genes that are essential in the context of particular copy-number alterations (copy-number associated gene dependencies). The most enriched class of copy-number associated gene dependencies was CYCLOPS (Copy-number alterations Yielding Cancer Liabilities Owing to Partial losS) genes, and spliceosome components were the most prevalent.

  17. Incorporating 16S Gene Copy Number Information Improves Estimates of Microbial Diversity and Abundance

    Science.gov (United States)

    Kembel, Steven W.; Wu, Martin; Eisen, Jonathan A.; Green, Jessica L.

    2012-01-01

    The abundance of different SSU rRNA (“16S”) gene sequences in environmental samples is widely used in studies of microbial ecology as a measure of microbial community structure and diversity. However, the genomic copy number of the 16S gene varies greatly – from one in many species to up to 15 in some bacteria and to hundreds in some microbial eukaryotes. As a result of this variation the relative abundance of 16S genes in environmental samples can be attributed both to variation in the relative abundance of different organisms, and to variation in genomic 16S copy number among those organisms. Despite this fact, many studies assume that the abundance of 16S gene sequences is a surrogate measure of the relative abundance of the organisms containing those sequences. Here we present a method that uses data on sequences and genomic copy number of 16S genes along with phylogenetic placement and ancestral state estimation to estimate organismal abundances from environmental DNA sequence data. We use theory and simulations to demonstrate that 16S genomic copy number can be accurately estimated from the short reads typically obtained from high-throughput environmental sequencing of the 16S gene, and that organismal abundances in microbial communities are more strongly correlated with estimated abundances obtained from our method than with gene abundances. We re-analyze several published empirical data sets and demonstrate that the use of gene abundance versus estimated organismal abundance can lead to different inferences about community diversity and structure and the identity of the dominant taxa in microbial communities. Our approach will allow microbial ecologists to make more accurate inferences about microbial diversity and abundance based on 16S sequence data. PMID:23133348

  18. Reduced purifying selection prevails over positive selection in human copy number variant evolution.

    Science.gov (United States)

    Nguyen, Duc-Quang; Webber, Caleb; Hehir-Kwa, Jayne; Pfundt, Rolph; Veltman, Joris; Ponting, Chris P

    2008-11-01

    Copy number variation is a dominant contributor to genomic variation and may frequently underlie an individual's variable susceptibilities to disease. Here we question our previous proposition that copy number variants (CNVs) are often retained in the human population because of their adaptive benefit. We show that genic biases of CNVs are best explained, not by positive selection, but by reduced efficiency of selection in eliminating deleterious changes from the human population. Of four CNV data sets examined, three exhibit significant increases in protein evolutionary rates. These increases appear to be attributable to the frequent coincidence of CNVs with segmental duplications (SDs) that recombine infrequently. Furthermore, human orthologs of mouse genes, which, when disrupted, result in pre- or postnatal lethality, are unusually depleted in CNVs. Together, these findings support a model of reduced purifying selection (Hill-Robertson interference) within copy number variable regions that are enriched in nonessential genes, allowing both the fixation of slightly deleterious substitutions and increased drift of CNV alleles. Additionally, all four CNV sets exhibited increased rates of interspecies chromosomal rearrangement and nucleotide substitution and an increased gene density. We observe that sequences with high G+C contents are most prone to copy number variation. In particular, frequently duplicated human SD sequence, or CNVs that are large and/or observed frequently, tend to be elevated in G+C content. In contrast, SD sequences that appear fixed in the human population lie more frequently within low G+C sequence. These findings provide an overarching view of how CNVs arise and segregate in the human population.

  19. Genome-wide copy number variation (CNV) in patients with autoimmune Addison's disease

    Science.gov (United States)

    2011-01-01

    Background Addison's disease (AD) is caused by an autoimmune destruction of the adrenal cortex. The pathogenesis is multi-factorial, involving genetic components and hitherto unknown environmental factors. The aim of the present study was to investigate if gene dosage in the form of copy number variation (CNV) could add to the repertoire of genetic susceptibility to autoimmune AD. Methods A genome-wide study using the Affymetrix GeneChip® Genome-Wide Human SNP Array 6.0 was conducted in 26 patients with AD. CNVs in selected genes were further investigated in a larger material of patients with autoimmune AD (n = 352) and healthy controls (n = 353) by duplex Taqman real-time polymerase chain reaction assays. Results We found that low copy number of UGT2B28 was significantly more frequent in AD patients compared to controls; conversely high copy number of ADAM3A was associated with AD. Conclusions We have identified two novel CNV associations to ADAM3A and UGT2B28 in AD. The mechanism by which this susceptibility is conferred is at present unclear, but may involve steroid inactivation (UGT2B28) and T cell maturation (ADAM3A). Characterization of these proteins may unravel novel information on the pathogenesis of autoimmunity. PMID:21851588

  20. Genome-wide copy number variation (CNV in patients with autoimmune Addison's disease

    Directory of Open Access Journals (Sweden)

    Brønstad Ingeborg

    2011-08-01

    Full Text Available Abstract Background Addison's disease (AD is caused by an autoimmune destruction of the adrenal cortex. The pathogenesis is multi-factorial, involving genetic components and hitherto unknown environmental factors. The aim of the present study was to investigate if gene dosage in the form of copy number variation (CNV could add to the repertoire of genetic susceptibility to autoimmune AD. Methods A genome-wide study using the Affymetrix GeneChip® Genome-Wide Human SNP Array 6.0 was conducted in 26 patients with AD. CNVs in selected genes were further investigated in a larger material of patients with autoimmune AD (n = 352 and healthy controls (n = 353 by duplex Taqman real-time polymerase chain reaction assays. Results We found that low copy number of UGT2B28 was significantly more frequent in AD patients compared to controls; conversely high copy number of ADAM3A was associated with AD. Conclusions We have identified two novel CNV associations to ADAM3A and UGT2B28 in AD. The mechanism by which this susceptibility is conferred is at present unclear, but may involve steroid inactivation (UGT2B28 and T cell maturation (ADAM3A. Characterization of these proteins may unravel novel information on the pathogenesis of autoimmunity.

  1. Proteomic changes resulting from gene copy number variations in cancer cells.

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    Tamar Geiger

    2010-09-01

    Full Text Available Along the transformation process, cells accumulate DNA aberrations, including mutations, translocations, amplifications, and deletions. Despite numerous studies, the overall effects of amplifications and deletions on the end point of gene expression--the level of proteins--is generally unknown. Here we use large-scale and high-resolution proteomics combined with gene copy number analysis to investigate in a global manner to what extent these genomic changes have a proteomic output and therefore the ability to affect cellular transformation. We accurately measure expression levels of 6,735 proteins and directly compare them to the gene copy number. We find that the average effect of these alterations on the protein expression is only a few percent. Nevertheless, by using a novel algorithm, we find the combined impact that many of these regional chromosomal aberrations have at the protein level. We show that proteins encoded by amplified oncogenes are often overexpressed, while adjacent amplified genes, which presumably do not promote growth and survival, are attenuated. Furthermore, regulation of biological processes and molecular complexes is independent of general copy number changes. By connecting the primary genome alteration to their proteomic consequences, this approach helps to interpret the data from large-scale cancer genomics efforts.

  2. Rare Copy Number Variants Identified Suggest the Regulating Pathways in Hypertension-Related Left Ventricular Hypertrophy.

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    Hoh Boon-Peng

    Full Text Available Left ventricular hypertrophy (LVH is an independent risk factor for cardiovascular morbidity and mortality, and a powerful predictor of adverse cardiovascular outcomes in the hypertensive patients. It has complex multifactorial and polygenic basis for its pathogenesis. We hypothesized that rare copy number variants (CNVs contribute to the LVH pathogenesis in hypertensive patients. Copy number variants (CNV were identified in 258 hypertensive patients, 95 of whom had LVH, after genotyping with a high resolution SNP array. Following stringent filtering criteria, we identified 208 rare, or private CNVs that were only present in our patients with hypertension related LVH. Preliminary findings from Gene Ontology and pathway analysis of this study confirmed the involvement of the genes known to be functionally involved in cardiac development and phenotypes, in line with previously reported transcriptomic studies. Network enrichment analyses suggested that the gene-set was, directly or indirectly, involved in the transcription factors regulating the "foetal cardiac gene programme" which triggered the hypertrophic cascade, confirming previous reports. These findings suggest that multiple, individually rare copy number variants altering genes may contribute to the pathogenesis of hypertension-related LVH. In summary, we have provided further supporting evidence that rare CNV could potentially impact this common and complex disease susceptibility with lower heritability.

  3. Allele-specific copy-number discovery from whole-genome and whole-exome sequencing

    Science.gov (United States)

    Wang, WeiBo; Wang, Wei; Sun, Wei; Crowley, James J.; Szatkiewicz, Jin P.

    2015-01-01

    Copy-number variants (CNVs) are a major form of genetic variation and a risk factor for various human diseases, so it is crucial to accurately detect and characterize them. It is conceivable that allele-specific reads from high-throughput sequencing data could be leveraged to both enhance CNV detection and produce allele-specific copy number (ASCN) calls. Although statistical methods have been developed to detect CNVs using whole-genome sequence (WGS) and/or whole-exome sequence (WES) data, information from allele-specific read counts has not yet been adequately exploited. In this paper, we develop an integrated method, called AS-GENSENG, which incorporates allele-specific read counts in CNV detection and estimates ASCN using either WGS or WES data. To evaluate the performance of AS-GENSENG, we conducted extensive simulations, generated empirical data using existing WGS and WES data sets and validated predicted CNVs using an independent methodology. We conclude that AS-GENSENG not only predicts accurate ASCN calls but also improves the accuracy of total copy number calls, owing to its unique ability to exploit information from both total and allele-specific read counts while accounting for various experimental biases in sequence data. Our novel, user-friendly and computationally efficient method and a complete analytic protocol is freely available at https://sourceforge.net/projects/asgenseng/. PMID:25883151

  4. c-myc copy number gain is a powerful prognosticator of disease outcome in cervical dysplasia.

    Science.gov (United States)

    Kübler, Kirsten; Heinenberg, Sally; Rudlowski, Christian; Keyver-Paik, Mignon-Denise; Abramian, Alina; Merkelbach-Bruse, Sabine; Büttner, Reinhard; Kuhn, Walther; Schildhaus, Hans-Ulrich

    2015-01-20

    Cervical carcinoma develops from preneoplasia by a multistep process. Although most low-grade dysplastic lesions will regress without intervention and even high-grade changes exhibit a substantial rate of regression, a small percentage of dysplasia will progress over time. Thus, indicators are needed to estimate the biological risk and to help avoid overtreatment in women who desire to preserve fertility. In addition to the classical biomarkers, PCR-ELISA-determined HPV genotype and immunohistochemically assessed p16INK4a and Ki-67 expression, cells with integrated HPV and copy number gain of TERC and c-myc were quantified in a panel of 104 benign, intraepithelial neoplastic (CIN I, II, III) and cancerous lesions using fluorescence in situ hybridization. Optimal cut-off values were calculated; Kaplan-Meier curves and a Cox proportional hazard regression model were used to evaluate prognostic signatures. The assay reliably identified HPV integration, TERC and c-myc copy number gain as determined by comparisons with established biomarkers. All biomarker levels increased with the progression of the disease. However, only c-myc copy number gain independently prognosticated a low probability of dysplastic regression. Our results suggest that c-myc plays a key role in the process of dysplastic transformation and might thus be exploited for treatment and follow-up decision-making of cervical dysplasia.

  5. Copy number of tandem direct repeats within the inverted repeats of Marek's disease virus DNA.

    Science.gov (United States)

    Kanamori, A; Nakajima, K; Ikuta, K; Ueda, S; Kato, S; Hirai, K

    1986-12-01

    We previously reported that DNA of the oncogenic strain BC-1 of Marek's disease virus serotype 1 (MDV1) contains three units of tandem direct repeats with 132 base pair (bp) repeats within the inverted repeats of the long regions of the MDV1 genome, whereas the attenuated, nononcogenic viral DNA contains multiple units of tandem direct repeats (Maotani et al., 1986). In the present study, the difference in the copy numbers of 132 bp repeats of oncogenic and nononcogenic MDV1 DNAs in other strains of MDV1 was investigated by Southern blot hybridization. The main copy numbers in different oncogenic MDV1 strains differed: those of BC-1, JM and highly oncogenic Md5 were 3, 5 to 12 and 2, respectively. The viral DNA population with two units of repeats was small, but detectable, in cells infected with either the oncogenic BC-1 or JM strain. The MDV1 DNA in various MD cell lines contained either two units or both two and three units of repeats. The significance of the copy number of repeats in oncogenicity of MDV1 is discussed.

  6. Sequence diversity and copy number variation of Mutator-like transposases in wheat

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    Nobuaki Asakura

    2008-01-01

    Full Text Available Partial transposase-coding sequences of Mutator-like elements (MULEs were isolated from a wild einkorn wheat, Triticum urartu, by degenerate PCR. The isolated sequences were classified into a MuDR or Class I clade and divided into two distinct subclasses (subclass I and subclass II. The average pair-wise identity between members of both subclasses was 58.8% at the nucleotide sequence level. Sequence diversity of subclass I was larger than that of subclass II. DNA gel blot analysis showed that subclass I was present as low copy number elements in the genomes of all Triticum and Aegilops accessions surveyed, while subclass II was present as high copy number elements. These two subclasses seemed uncapable of recognizing each other for transposition. The number of copies of subclass II elements was much higher in Aegilops with the S, Sl and D genomes and polyploid Triticum species than in diploid Triticum with the A genome, indicating that active transposition occurred in S, Sl and D genomes before polyploidization. DNA gel blot analysis of six species selected from three subfamilies of Poaceae demonstrated that only the tribe Triticeae possessed both subclasses. These results suggest that the differentiation of these two subclasses occurred before or immediately after the establishment of the tribe Triticeae.

  7. ReadDepth: a parallel R package for detecting copy number alterations from short sequencing reads.

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    Christopher A Miller

    Full Text Available Copy number alterations are important contributors to many genetic diseases, including cancer. We present the readDepth package for R, which can detect these aberrations by measuring the depth of coverage obtained by massively parallel sequencing of the genome. In addition to achieving higher accuracy than existing packages, our tool runs much faster by utilizing multi-core architectures to parallelize the processing of these large data sets. In contrast to other published methods, readDepth does not require the sequencing of a reference sample, and uses a robust statistical model that accounts for overdispersed data. It includes a method for effectively increasing the resolution obtained from low-coverage experiments by utilizing breakpoint information from paired end sequencing to do positional refinement. We also demonstrate a method for inferring copy number using reads generated by whole-genome bisulfite sequencing, thus enabling integrative study of epigenomic and copy number alterations. Finally, we apply this tool to two genomes, showing that it performs well on genomes sequenced to both low and high coverage. The readDepth package runs on Linux and MacOSX, is released under the Apache 2.0 license, and is available at http://code.google.com/p/readdepth/.

  8. Detection of CAPN10 copy number variation in Thai patients with type 2 diabetes by denaturing high performance liquid chromatography and real-time quantitative polymerase chain reaction

    Science.gov (United States)

    Plengvidhya, Nattachet; Chanprasert, Kanjana; Tangjittipokin, Watip; Thongnoppakhun, Wanna; Yenchitsomanus, Pa-thai

    2015-01-01

    Aims/Introduction A combination of multiple genetic and environmental factors contribute to the pathogenesis of type 2 diabetes. Copy number variations (CNVs) are associated with complex human diseases. However, CNVs can cause genotype deviation from the Hardy–Weinberg equilibrium (HWE). A genetic case–control association study in 216 Thai diabetic patients and 192 non-diabetic controls found that, after excluding genotyping errors, genotype distribution of calpain 10 (CAPN10) SNP44 (rs2975760) deviated from HWE. Here, we aimed to detect CNV within the CAPN10 SNP44 region. Materials and Methods CNV within the CAPN10 SNP44 region was detected using denaturing high-performance liquid chromatography, and the results confirmed by real-time quantitative polymerase chain reaction with SYBR Green I. Results Both methods successfully identified CNV in the CAPN10 SNP44 region, obtaining concordant results. Correction of genotype calling based on the status of identified CNVs showed that the CAPN10 SNP44 genotype is in good agreement with HWE (P > 0.05). However, no association between CNV genotypes and risk of type 2 diabetes was observed. Conclusions Identified CNVs for CAPN10 SNP44 genotypes lead to deviation from HWE. Furthermore, both denaturing high-performance liquid chromatography and real-time quantitative polymerase chain reaction are useful for detecting CNVs. PMID:26543536

  9. sCNAphase: using haplotype resolved read depth to genotype somatic copy number alterations from low cellularity aneuploid tumors.

    Science.gov (United States)

    Chen, Wenhan; Robertson, Alan J; Ganesamoorthy, Devika; Coin, Lachlan J M

    2017-03-17

    Accurate identification of copy number alterations is an essential step in understanding the events driving tumor progression. While a variety of algorithms have been developed to use high-throughput sequencing data to profile copy number changes, no tool is able to reliably characterize ploidy and genotype absolute copy number from tumor samples that contain less than 40% tumor cells. To increase our power to resolve the copy number profile from low-cellularity tumor samples, we developed a novel approach that pre-phases heterozygote germline single nucleotide polymorphisms (SNPs) in order to replace the commonly used 'B-allele frequency' with a more powerful 'parental-haplotype frequency'. We apply our tool-sCNAphase-to characterize the copy number and loss-of-heterozygosity profiles of four publicly available breast cancer cell-lines. Comparisons to previous spectral karyotyping and microarray studies revealed that sCNAphase reliably identified overall ploidy as well as the individual copy number mutations from each cell-line. Analysis of artificial cell-line mixtures demonstrated the capacity of this method to determine the level of tumor cellularity, consistently identify sCNAs and characterize ploidy in samples with as little as 10% tumor cells. This novel methodology has the potential to bring sCNA profiling to low-cellularity tumors, a form of cancer unable to be accurately studied by current methods. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  10. Increased pfmdr1 copy number in Plasmodium falciparum isolates from Suriname.

    Science.gov (United States)

    Labadie-Bracho, Mergiory; Adhin, Malti R

    2013-07-01

    Amplification of the pfmdr1 gene is associated with clinical failures and reduced in vivo and in vitro sensitivity to both mefloquine and artemether-lumefantrine in South-East Asia. Several African countries have reported the absence or very low prevalence of increased copy number, whilst South American reports are limited to Peru without and Venezuela with increased pfmdr1 multiplication. The relative pfmdr1 copy numbers were assessed in 68 isolates from Suriname collected from different endemic villages (2005) and from mining areas (2009). 11% of the isolates harbour multiple copies of the pfmdr1 gene. Isolates originating from mining areas do not yet display a higher tendency for increased copy number and no significant differences could be registered within a time span of 4 years, but the mere presence of increased copy number warrants caution and should be considered as an early warning sign for emerging drug resistance in Suriname and South America.

  11. Copy-number gains of HUWE1 due to replication- and recombination-based rearrangements.

    Science.gov (United States)

    Froyen, Guy; Belet, Stefanie; Martinez, Francisco; Santos-Rebouças, Cíntia Barros; Declercq, Matthias; Verbeeck, Jelle; Donckers, Lene; Berland, Siren; Mayo, Sonia; Rosello, Monica; Pimentel, Márcia Mattos Gonçalves; Fintelman-Rodrigues, Natalia; Hovland, Randi; Rodrigues dos Santos, Suely; Raymond, F Lucy; Bose, Tulika; Corbett, Mark A; Sheffield, Leslie; van Ravenswaaij-Arts, Conny M A; Dijkhuizen, Trijnie; Coutton, Charles; Satre, Veronique; Siu, Victoria; Marynen, Peter

    2012-08-10

    We previously reported on nonrecurrent overlapping duplications at Xp11.22 in individuals with nonsyndromic intellectual disability (ID) harboring HSD17B10, HUWE1, and the microRNAs miR-98 and let-7f-2 in the smallest region of overlap. Here, we describe six additional individuals with nonsyndromic ID and overlapping microduplications that segregate in the families. High-resolution mapping of the 12 copy-number gains reduced the minimal duplicated region to the HUWE1 locus only. Consequently, increased mRNA levels were detected for HUWE1, but not HSD17B10. Marker and SNP analysis, together with identification of two de novo events, suggested a paternally derived intrachromosomal duplication event. In four independent families, we report on a polymorphic 70 kb recurrent copy-number gain, which harbors part of HUWE1 (exon 28 to 3' untranslated region), including miR-98 and let-7f-2. Our findings thus demonstrate that HUWE1 is the only remaining dosage-sensitive gene associated with the ID phenotype. Junction and in silico analysis of breakpoint regions demonstrated simple microhomology-mediated rearrangements suggestive of replication-based duplication events. Intriguingly, in a single family, the duplication was generated through nonallelic homologous recombination (NAHR) with the use of HUWE1-flanking imperfect low-copy repeats, which drive this infrequent NAHR event. The recurrent partial HUWE1 copy-number gain was also generated through NAHR, but here, the homologous sequences used were identified as TcMAR-Tigger DNA elements, a template that has not yet been reported for NAHR. In summary, we showed that an increased dosage of HUWE1 causes nonsyndromic ID and demonstrated that the Xp11.22 region is prone to recombination- and replication-based rearrangements.

  12. [Research on potential interaction between mitochondrial DNA copy number and related factors on risk of hypertension in coal miners].

    Science.gov (United States)

    Guo, J Y; Lei, L J; Qiao, N; Fan, G Q; Sun, C M; Huang, J J; Wang, T

    2017-01-10

    Objective: To investigate the effects of mitochondrial DNA (mtDNA) copy number in peripheral blood and related factors on the risk of hypertension in coal miners. Methods: A case-control study was conducted in 378 coal miners with hypertension and 325 healthy coal miners recruited from Datong Coal Mine Group. A standard questionnaire was used to collect their general information, such as demographic characteristics, habits and occupational history. Fluorescence quantitative PCR was performed to detect the copy number of mtDNA. Logistic regression model was applied for identifying the related risk factors of hypertension and analyzing the interaction between mtDNA copy number and risk factors. Results: The prevalence of hypertension of high mtDNA copy number was lower than mtDNA copy numberin 0-5.67 group, but the difference was not statistically significant (P=0.414). Alcohol drinking (OR=1.80, 95% CI: 1.26-2.56), family history of hypertension (OR=1.74, 95% CI: 1.20- 2.50), work shifts (OR=0.69, 95% CI: 0.48-0.99), education level (P=0.012) and family monthly income level (P=0.001) were related to the prevalence of hypertension. There were potential interactions between mtDNA copy number and alcohol drinking, family monthly income level, family history of hypertension, respectively. Alcohol drinking was a risk factor for hypertension [1.77 (1.25-2.50)]. Potential interactions between mtDNA copy number and alcohol drinking reduced the risk of hypertension (OR=1.20, 95% CI: 1.07-1.35). Family history of hypertension was a risk factor for hypertension [1.81(1.26-2.59)]. Potential interactions between mtDNA copy number and family history of hypertension reduced the risk of hypertension (OR=1.24, 95%CI: 1.09-1.41). Family monthly income level was a protect factor for hypertension [0.55(0.46-0.66)]. Potential interactions between mtDNA copy number and family monthly income level increased the protection role of hypertension (OR=0.90, 95% CI: 0.86-0.94). Conclusion: mt

  13. Copy number gain at Xp22.31 includes complex duplication rearrangements and recurrent triplications.

    Science.gov (United States)

    Liu, Pengfei; Erez, Ayelet; Nagamani, Sandesh C Sreenath; Bi, Weimin; Carvalho, Claudia M B; Simmons, Alexandra D; Wiszniewska, Joanna; Fang, Ping; Eng, Patricia A; Cooper, M Lance; Sutton, V Reid; Roeder, Elizabeth R; Bodensteiner, John B; Delgado, Mauricio R; Prakash, Siddharth K; Belmont, John W; Stankiewicz, Pawel; Berg, Jonathan S; Shinawi, Marwan; Patel, Ankita; Cheung, Sau Wai; Lupski, James R

    2011-05-15

    Genomic instability is a feature of the human Xp22.31 region wherein deletions are associated with X-linked ichthyosis, mental retardation and attention deficit hyperactivity disorder. A putative homologous recombination hotspot motif is enriched in low copy repeats that mediate recurrent deletion at this locus. To date, few efforts have focused on copy number gain at Xp22.31. However, clinical testing revealed a high incidence of duplication of Xp22.31 in subjects ascertained and referred with neurobehavioral phenotypes. We systematically studied 61 unrelated subjects with rearrangements revealing gain in copy number, using multiple molecular assays. We detected not only the anticipated recurrent and simple nonrecurrent duplications, but also unexpectedly identified recurrent triplications and other complex rearrangements. Breakpoint analyses enabled us to surmise the mechanisms for many of these rearrangements. The clinical significance of the recurrent duplications and triplications were assessed using different approaches. We cannot find any evidence to support pathogenicity of the Xp22.31 duplication. However, our data suggest that the Xp22.31 duplication may serve as a risk factor for abnormal phenotypes. Our findings highlight the need for more robust Xp22.31 triplication detection in that such further gain may be more penetrant than the duplications. Our findings reveal the distribution of different mechanisms for genomic duplication rearrangements at a given locus, and provide insights into aspects of strand exchange events between paralogous sequences in the human genome.

  14. Cell-free DNA copy number variations in plasma from colorectal cancer patients.

    Science.gov (United States)

    Li, Jian; Dittmar, Rachel L; Xia, Shu; Zhang, Huijuan; Du, Meijun; Huang, Chiang-Ching; Druliner, Brooke R; Boardman, Lisa; Wang, Liang

    2017-08-01

    To evaluate the clinical utility of cell-free DNA (cfDNA), we performed whole-genome sequencing to systematically examine plasma cfDNA copy number variations (CNVs) in a cohort of patients with colorectal cancer (CRC, n = 80), polyps (n = 20), and healthy controls (n = 35). We initially compared cfDNA yield in 20 paired serum-plasma samples and observed significantly higher cfDNA concentration in serum (median = 81.20 ng, range 7.18-500 ng·mL(-1) ) than in plasma (median = 5.09 ng, range 3.76-62.8 ng·mL(-1) ) (P copy number analysis showed common CNVs in multiple chromosomal regions, including amplifications on 1q, 8q, and 5q and deletions on 1p, 4q, 8p, 17p, 18q, and 22q. Copy number changes were also evident in genes critical to the cell cycle, DNA repair, and WNT signaling pathways. To evaluate whether cumulative copy number changes were associated with tumor stages, we calculated plasma genomic abnormality in colon cancer (PGA-C) score by summing the most significant CNVs. The PGA-C score showed predictive performance with an area under the curve from 0.54 to 0.84 for CRC stages I-IV. Locus-specific copy number analysis identified nine genomic regions where CNVs were significantly associated with survival in stage III-IV CRC patients. A multivariate model using six of nine genomic regions demonstrated a significant association of high-risk score with shorter survival (HR = 5.33, 95% CI = 6.76-94.44, P < 0.0001). Our study demonstrates the importance of using plasma (rather than serum) to test tumor-related genomic variations. Plasma cfDNA-based tests can capture tumor-specific genetic changes and may provide a measurable classifier for assessing clinical outcomes in advanced CRC patients. © 2017 The Authors. Published by FEBS Press and John Wiley & Sons Ltd.

  15. Copy number of the transposon, Pokey, in rDNA is positively correlated with rDNA copy number in Daphnia obtuse [corrected].

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    Kaitlynn LeRiche

    Full Text Available Pokey is a class II DNA transposon that inserts into 28S ribosomal RNA (rRNA genes and other genomic regions of species in the subgenus, Daphnia. Two divergent lineages, PokeyA and PokeyB have been identified. Recombination between misaligned rRNA genes changes their number and the number of Pokey elements. We used quantitative PCR (qPCR to estimate rRNA gene and Pokey number in isolates from natural populations of Daphnia obtusa, and in clonally-propagated mutation accumulation lines (MAL initiated from a single D. obtusa female. The change in direction and magnitude of Pokey and rRNA gene number did not show a consistent pattern across ∼ 87 generations in the MAL; however, Pokey and rRNA gene number changed in concert. PokeyA and 28S gene number were positively correlated in the isolates from both natural populations and the MAL. PokeyB number was much lower than PokeyA in both MAL and natural population isolates, and showed no correlation with 28S gene number. Preliminary analysis did not detect PokeyB outside rDNA in any isolates and detected only 0 to 4 copies of PokeyA outside rDNA indicating that Pokey may be primarily an rDNA element in D. obtusa. The recombination rate in this species is high and the average size of the rDNA locus is about twice as large as that in other Daphnia species such as D. pulicaria and D. pulex, which may have facilitated expansion of PokeyA to much higher numbers in D. obtusa rDNA than these other species.

  16. Decreases in average bacterial community rRNA operon copy number during succession.

    Science.gov (United States)

    Nemergut, Diana R; Knelman, Joseph E; Ferrenberg, Scott; Bilinski, Teresa; Melbourne, Brett; Jiang, Lin; Violle, Cyrille; Darcy, John L; Prest, Tiffany; Schmidt, Steven K; Townsend, Alan R

    2016-05-01

    Trait-based studies can help clarify the mechanisms driving patterns of microbial community assembly and coexistence. Here, we use a trait-based approach to explore the importance of rRNA operon copy number in microbial succession, building on prior evidence that organisms with higher copy numbers respond more rapidly to nutrient inputs. We set flasks of heterotrophic media into the environment and examined bacterial community assembly at seven time points. Communities were arrayed along a geographic gradient to introduce stochasticity via dispersal processes and were analyzed using 16 S rRNA gene pyrosequencing, and rRNA operon copy number was modeled using ancestral trait reconstruction. We found that taxonomic composition was similar between communities at the beginning of the experiment and then diverged through time; as well, phylogenetic clustering within communities decreased over time. The average rRNA operon copy number decreased over the experiment, and variance in rRNA operon copy number was lowest both early and late in succession. We then analyzed bacterial community data from other soil and sediment primary and secondary successional sequences from three markedly different ecosystem types. Our results demonstrate that decreases in average copy number are a consistent feature of communities across various drivers of ecological succession. Importantly, our work supports the scaling of the copy number trait over multiple levels of biological organization, ranging from cells to populations and communities, with implications for both microbial ecology and evolution.

  17. Integration of transcript expression, copy number and LOH analysis of infiltrating ductal carcinoma of the breast

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    Hawthorn Lesleyann

    2010-08-01

    Full Text Available Abstract Background A major challenge in the interpretation of genomic profiling data generated from breast cancer samples is the identification of driver genes as distinct from bystander genes which do not impact tumorigenesis. One way to assess the relative importance of alterations in the transcriptome profile is to combine parallel analyses that assess changes in the copy number alterations (CNAs. This integrated analysis permits the identification of genes with altered expression that map within specific chromosomal regions which demonstrate copy number alterations, providing a mechanistic approach to identify the 'driver genes'. Methods We have performed whole genome analysis of CNAs using the Affymetrix 250K Mapping array on 22 infiltrating ductal carcinoma samples (IDCs. Analysis of transcript expression alterations was performed using the Affymetrix U133 Plus2.0 array on 16 IDC samples. Fourteen IDC samples were analyzed using both platforms and the data integrated. We also incorporated data from loss of heterozygosity (LOH analysis to identify genes showing altered expression in LOH regions. Results Common chromosome gains and amplifications were identified at 1q21.3, 6p21.3, 7p11.2-p12.1, 8q21.11 and 8q24.3. A novel amplicon was identified at 5p15.33. Frequent losses were found at 1p36.22, 8q23.3, 11p13, 11q23, and 22q13. Over 130 genes were identified with concurrent increases or decreases in expression that mapped to these regions of copy number alterations. LOH analysis revealed three tumors with whole chromosome or p arm allelic loss of chromosome 17. Genes were identified that mapped to copy neutral LOH regions. LOH with accompanying copy loss was detected on Xp24 and Xp25 and genes mapping to these regions with decreased expression were identified. Gene expression data highlighted the PPARα/RXRα Activation Pathway as down-regulated in the tumor samples. Conclusion We have demonstrated the utility of the application of

  18. Molecular profiling of gene copy number abnormalities in key regulatory genes in high-risk B-lineage acute lymphoblastic leukemia: frequency and their association with clinicopathological findings in Indian patients.

    Science.gov (United States)

    Bhandari, Prerana; Ahmad, Firoz; Das, Bibhu Ranjan

    2017-05-01

    Genes related to key cellular pathways are frequently altered in B cell ALL and are associated with poor survival especially in high-risk (HR) subgroups. We examined gene copy number abnormalities (CNA) in 101 Indian HR B cell ALL patients and their correlation with clinicopathological features by multiplex ligation-dependent probe amplification. Overall, CNA were detected in 59 (59%) cases, with 26, 10 and 23% of cases harboring 1, 2 or +3 CNA. CNA were more prevalent in BCR-ABL1 (60%), pediatric (64%) and high WCC (WBC count) (63%) patients. Frequent genes deletions included CDNK2A/B (26%), IKZF1 (25%), PAX5 (14%), JAK2 (7%), BTG1 (6%), RB1 (5%), EBF1 (4%), ETV6 (4%), while PAR1 region genes were predominantly duplicated (20%). EBF1 deletions selectively associated with adults, IKZF1 deletions occurred frequently in high WCC and BCR-ABL1 cases, while PAR1 region gains significantly associated with MLL-AF4 cases. IKZF1 haploinsufficiency group was predominant, especially in adults (65%), high WCC (60%) patients and BCR-ABL1-negative (78%) patients. Most cases harbored multiple concurrent CNA, with IKZF1 concomitantly occurring with CDNK2A/B, PAX5 and BTG1, while JAK2 occurred with CDNK2A/B and PAX5. Mutually exclusive CNA included ETV6 and IKZF1/RB1, and EBF1 and JAK2. Our results corroborate with global reports, aggregating molecular markers in Indian HR B-ALL cases. Integration of CNA data from rapid methods like MLPA, onto background of existing gold-standard methods detecting significant chromosomal abnormalities, provides a comprehensive genetic profile in B-ALL.

  19. Assessing Mitochondrial DNA Variation and Copy Number in Lymphocytes of ~2,000 Sardinians Using Tailored Sequencing Analysis Tools.

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    Jun Ding

    2015-07-01

    Full Text Available DNA sequencing identifies common and rare genetic variants for association studies, but studies typically focus on variants in nuclear DNA and ignore the mitochondrial genome. In fact, analyzing variants in mitochondrial DNA (mtDNA sequences presents special problems, which we resolve here with a general solution for the analysis of mtDNA in next-generation sequencing studies. The new program package comprises 1 an algorithm designed to identify mtDNA variants (i.e., homoplasmies and heteroplasmies, incorporating sequencing error rates at each base in a likelihood calculation and allowing allele fractions at a variant site to differ across individuals; and 2 an estimation of mtDNA copy number in a cell directly from whole-genome sequencing data. We also apply the methods to DNA sequence from lymphocytes of ~2,000 SardiNIA Project participants. As expected, mothers and offspring share all homoplasmies but a lesser proportion of heteroplasmies. Both homoplasmies and heteroplasmies show 5-fold higher transition/transversion ratios than variants in nuclear DNA. Also, heteroplasmy increases with age, though on average only ~1 heteroplasmy reaches the 4% level between ages 20 and 90. In addition, we find that mtDNA copy number averages ~110 copies/lymphocyte and is ~54% heritable, implying substantial genetic regulation of the level of mtDNA. Copy numbers also decrease modestly but significantly with age, and females on average have significantly more copies than males. The mtDNA copy numbers are significantly associated with waist circumference (p-value = 0.0031 and waist-hip ratio (p-value = 2.4×10-5, but not with body mass index, indicating an association with central fat distribution. To our knowledge, this is the largest population analysis to date of mtDNA dynamics, revealing the age-imposed increase in heteroplasmy, the relatively high heritability of copy number, and the association of copy number with metabolic traits.

  20. K13 mutations and pfmdr1 copy number variation in Plasmodium falciparum malaria in Myanmar.

    Science.gov (United States)

    Win, Aye A; Imwong, Mallika; Kyaw, Myat P; Woodrow, Charles J; Chotivanich, Kesinee; Hanboonkunupakarn, Borimas; Pukrittayakamee, Sasithon

    2016-02-24

    Artemisinin-based combination therapy has been first-line treatment for falciparum malaria in Myanmar since 2005. The wide extent of artemisinin resistance in the Greater Mekong sub-region and the presence of mefloquine resistance at the Myanmar-Thailand border raise concerns over resistance patterns in Myanmar. The availability of molecular markers for resistance to both drugs enables assessment even in remote malaria-endemic areas. A total of 250 dried blood spot samples collected from patients with Plasmodium falciparum malarial infection in five malaria-endemic areas across Myanmar were analysed for kelch 13 sequence (k13) and pfmdr1 copy number variation. K13 mutations in the region corresponding to amino acids 210-726 (including the propeller region of the protein) were detected by nested PCR amplification and sequencing, and pfmdr1 copy number variation by real-time PCR. In two sites, a sub-set of patients were prospectively followed up for assessment of day-3 parasite clearance rates after a standard course of artemether-lumefantrine. K13 mutations and pfmdr1 amplification were successfully analysed in 206 and 218 samples, respectively. Sixty-nine isolates (33.5 %) had mutations within the k13 propeller region with 53 of these (76.8 %) having mutations already known to be associated with artemisinin resistance. F446I (32 isolates) and P574L (15 isolates) were the most common examples. K13 mutation was less common in sites in western border regions (29 of 155 isolates) compared to samples from the east and north (40 of 51 isolates; p < 0.0001). The overall proportion of parasites with multiple pfmdr1 copies (greater than 1.5) was 5.5 %. Seven samples showed both k13 mutation and multiple copies of pfmdr1. Only one of 36 patients followed up after artemether-lumefantrine treatment still had parasites at day 3; molecular analysis indicated wild-type k13 and single copy pfmdr1. The proportion of P. falciparum isolates with mutations in the propeller region of k

  1. Post-polyploidisation morphotype diversification associates with gene copy number variation

    Science.gov (United States)

    Schiessl, Sarah; Huettel, Bruno; Kuehn, Diana; Reinhardt, Richard; Snowdon, Rod

    2017-01-01

    Genetic models for polyploid crop adaptation provide important information relevant for future breeding prospects. A well-suited model is Brassica napus, a recent allopolyploid closely related to Arabidopsis thaliana. Flowering time is a major adaptation trait determining life cycle synchronization with the environment. Here we unravel natural genetic variation in B. napus flowering time regulators and investigate associations with evolutionary diversification into different life cycle morphotypes. Deep sequencing of 35 flowering regulators was performed in 280 diverse B. napus genotypes. High sequencing depth enabled high-quality calling of single-nucleotide polymorphisms (SNPs), insertion-deletions (InDels) and copy number variants (CNVs). By combining these data with genotyping data from the Brassica 60 K Illumina® Infinium SNP array, we performed a genome-wide marker distribution analysis across the 4 ecogeographical morphotypes. Twelve haplotypes, including Bna.FLC.A10, Bna.VIN3.A02 and the Bna.FT promoter on C02_random, were diagnostic for the diversification of winter and spring types. The subspecies split between oilseed/kale (B. napus ssp. napus) and swedes/rutabagas (B. napus ssp. napobrassica) was defined by 13 haplotypes, including genomic rearrangements encompassing copies of Bna.FLC, Bna.PHYA and Bna.GA3ox1. De novo variation in copies of important flowering-time genes in B. napus arose during allopolyploidisation, enabling sub-functionalisation that allowed different morphotypes to appropriately fine-tune their lifecycle. PMID:28165502

  2. Use of Quantitative Polymerase Chain Reaction for Determining Copy Numbers of Transgenes in Lesquerella fendleri

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    Grace Q. Chen

    2010-01-01

    Full Text Available Problem statement: In transgenic plants, the number of transgene copies could greatly influence the level of expression and genetic stability of the target gene, thus it is important to develop an efficient method for accurate estimation of transgene copies. The quantitative Polymerase Chain Reaction (qPCR technique is becoming more efficient nowadays to determine copy numbers of transgenes in transgenic plants, being used here, for the first time in quantifying copy numbers of transgenes in Lesquerella fendleri. Approach: The system utilized a known one copy gene, LfKCS4/5, from L. fendleri as an endogenous calibrator and the threshold Crossing point (Ct measured by Applied Biosystem 7500 system to calculate the copy numbers of transgenes in primary transgenic lines (T0 generation. Results: The qPCR condition was optimized and each primer set had a PCR efficiency of 0.99 or 1.01. Our data demonstrated unambiguous 2-fold discrimination of the copy number of β-glucuronidase gene (gusA and hygromycine phosphotransferase II (hptII genes in 12 T0 lines. Most of the lines contained one or two copies of each gene. Eight out of 12 samples (66.7% showed more copies of gusA gene than that of hptII gene, suggesting rearrangements of the Transferred (T-DNA. Possible modifications of the T-DNA cassette in L. fendleri are discussed based on main models of T-DNA integration in the plant genome. Conclusion: The qPCR described in this study is an efficient method and it is particularly useful in identification and selection of transgenic plants with desirable copy numbers at early stage.

  3. Beta-defensin genomic copy number is not a modifier locus for cystic fibrosis

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    Burgess Juliana

    2005-12-01

    Full Text Available Abstract Human beta-defensin 2 (DEFB4, also known as DEFB2 or hBD-2 is a salt-sensitive antimicrobial protein that is expressed in lung epithelia. Previous work has shown that it is encoded in a cluster of beta-defensin genes at 8p23.1, which varies in copy number between 2 and 12 in different individuals. We determined the copy number of this locus in 355 patients with cystic fibrosis (CF, and tested for correlation between beta-defensin cluster genomic copy number and lung disease associated with CF. No significant association was found.

  4. Mitochondrial DNA copy number in peripheral blood cells declines with age and is associated with general health among elderly.

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    Mengel-From, Jonas; Thinggaard, Mikael; Dalgård, Christine; Kyvik, Kirsten Ohm; Christensen, Kaare; Christiansen, Lene

    2014-09-01

    The role of the mitochondria in disease, general health and aging has drawn much attention over the years. Several attempts have been made to describe how the numbers of mitochondria correlate with age, although with inconclusive results. In this study, the relative quantity of mitochondrial DNA compared to nuclear DNA, i.e. the mitochondrial DNA copy number, was measured by PCR technology and used as a proxy for the content of mitochondria copies. In 1,067 Danish twins and singletons (18-93 years of age), with the majority being elderly individuals, the estimated mean mitochondrial DNA copy number in peripheral blood cells was similar for those 18-48 years of age [mean relative mtDNA content: 61.0; 95 % CI (52.1; 69.9)], but declined by -0.54 mtDNA 95 % CI (-0.63; -0.45) every year for those older than approximately 50 years of age. However, the longitudinal, yearly decline within an individual was more than twice as steep as observed in the cross-sectional analysis [decline of mtDNA content: -1.27; 95 % CI (-1.71; -0.82)]. Subjects with low mitochondrial DNA copy number had poorer outcomes in terms of cognitive performance, physical strength, self-rated health, and higher all-cause mortality than subjects with high mitochondrial DNA copy number, also when age was controlled for. The copy number mortality association can contribute to the smaller decline in a cross-sectional sample of the population compared to the individual, longitudinal decline. This study suggests that high mitochondrial DNA copy number in blood is associated with better health and survival among elderly.

  5. Association between TLR7 copy number variations and hepatitis B virus infection outcome in Chinese.

    Science.gov (United States)

    Li, Fang; Li, Xu; Zou, Gui-Zhou; Gao, Yu-Feng; Ye, Jun

    2017-03-07

    To explore whether copy number variations (CNVs) of toll-like receptor 7 (TLR7) are associated with susceptibility to chronic hepatitis B virus (HBV) infection. This study included 623 patients (495 males and 128 females) with chronic hepatitis B virus infection (CHB) and 300 patients (135 females and 165 males) with acute hepatitis B virus infection (AHB) as controls. All CHB patients were further categorized according to disease progression after HBV infection (CHB, liver cirrhosis, or hepatocellular carcinoma). Copy numbers of the TLR7 gene were measured using the AccuCopy method. χ(2) tests were used to evaluate the association between TLR7 CNVs and infection type. P values, odds ratios, and 95% confidence intervals (CIs) were used to estimate the effects of risk. Among male patients, there were significant differences between the AHB group and CHB group in the distribution of TLR7 CNVs. Low copy number of TLR7 was significantly associated with chronic HBV infection (OR = 0.329, 95%CI: 0.229-0.473, P copy number was also found between AHB and CHB female patients, with low copy number again associated with an increased risk of chronic HBV infection (OR = 0.292, 95%CI: 0.173-0.492, P copy number among the three types of chronic HBV infection (CHB, liver cirrhosis, or hepatocellular carcinoma). In addition, there was no association between TLR7 copy number and titer of the HBV e antigen. Low TLR7 copy number is a risk factor for chronic HBV infection but is not associated with later stages of disease progression.

  6. Association between TLR7 copy number variations and hepatitis B virus infection outcome in Chinese

    Science.gov (United States)

    Li, Fang; Li, Xu; Zou, Gui-Zhou; Gao, Yu-Feng; Ye, Jun

    2017-01-01

    AIM To explore whether copy number variations (CNVs) of toll-like receptor 7 (TLR7) are associated with susceptibility to chronic hepatitis B virus (HBV) infection. METHODS This study included 623 patients (495 males and 128 females) with chronic hepatitis B virus infection (CHB) and 300 patients (135 females and 165 males) with acute hepatitis B virus infection (AHB) as controls. All CHB patients were further categorized according to disease progression after HBV infection (CHB, liver cirrhosis, or hepatocellular carcinoma). Copy numbers of the TLR7 gene were measured using the AccuCopy method. χ2 tests were used to evaluate the association between TLR7 CNVs and infection type. P values, odds ratios, and 95% confidence intervals (CIs) were used to estimate the effects of risk. RESULTS Among male patients, there were significant differences between the AHB group and CHB group in the distribution of TLR7 CNVs. Low copy number of TLR7 was significantly associated with chronic HBV infection (OR = 0.329, 95%CI: 0.229-0.473, P < 0.001). Difference in TLR7 copy number was also found between AHB and CHB female patients, with low copy number again associated with an increased risk of chronic HBV infection (OR = 0.292, 95%CI: 0.173-0.492, P < 0.001). However, there were no significant differences in TLR7 copy number among the three types of chronic HBV infection (CHB, liver cirrhosis, or hepatocellular carcinoma). In addition, there was no association between TLR7 copy number and titer of the HBV e antigen. CONCLUSION Low TLR7 copy number is a risk factor for chronic HBV infection but is not associated with later stages of disease progression.

  7. A genome wide association study between copy number variation (CNV) and human height in Chinese population

    Institute of Scientific and Technical Information of China (English)

    Xi Li; Liang Zhang; Han Yan; Feng Pan; Zhixin Zhang; Yumei Peng; Qi Zhou; Lina He; Xuezhen Zhu; Jing Cheng; Lishu Zhang; Lijun Tan; Yaozhong Liu; Qing Tian; Hongwen Deng; Xiaogang Liu; Shufeng Lei; Tielin Yang; Xiangding Chen; Fang Zhang; Yue Fang; Yan Guo

    2010-01-01

    Copy number variation (CNV) is a type of genetic variation which may have important roles in phenotypic variability and disease susceptibility. To hunt for genetic variants underlying human height variation, we performed a genome wide CNV association study for human height in 618 Chinese unrelated subjects using Affymetrix 500K array set. After adjusting for age and sex, we found that four CNVs at 6p21.3, 8p23.3-23.2, 9p23 and 16p12.1 were associated with human height (with borderline significant p value: 0.013, 0.011, 0.024, 0.049; respectively). However, after multiple tests correction, none of them was associated with human height. We observed that the gain of copy number (more than 2 copies) at 8p23.3-23.2 was associated with lower height (normal copy number vs. gain of copy number; 161.2 cm vs. 153.7 cm, p = 0.011), which accounted for 0.9% of height variation. Loss of copy number (less than 2 copies) at 6p21.3 was associated with 0.8% lower height (loss of copy number vs. normal copy number: 154.5 cm vs. 161.1 cm, p = 0.013). Since no important genes influencing height located in CNVs at loci of 8p23.3-23.2 and 6p21.3, the two CNVs may cause the structural rearrangements of neighbored important candidate genes, thus regulates the variation of height. Our results expand our knowledge of the genetic factors underlying height variation and the biological regulation of human height.

  8. Mitochondrial DNA copy number variation as a potential predictor of renal cell carcinoma.

    Science.gov (United States)

    Elsayed, Eman T; Hashad, Mohamed M; Elgohary, Iman E

    2017-07-24

    Peripheral blood mitochondrial DNA (mtDNA) copy number alteration has been suggested as a risk factor for several types of cancer. The aim of the present study was to assess the role of peripheral blood mtDNA copy number variation as a noninvasive biomarker in the prediction and early detection of renal cell carcinoma (RCC) in a cohort of Egyptian patients. Quantitative real-time polymerase chain reaction (qPCR) was used to measure peripheral blood mtDNA copy numbers in 57 patients with newly diagnosed, early-stage localized RCC and 60 age- and sex-matched healthy individuals as a control group. Median mtDNA copy number was significantly higher in RCC cases than in controls (166 vs. 91, pcopy number was associated with an 18-fold increased risk of RCC (95% confidence interval: 5.065-63.9). On receiver operating characteristic curve analysis, it was found that mtDNA could distinguish between RCC patients and healthy controls, with 86% sensitivity, 80% specificity, 80.3% positive predictive value and 85.7% negative predictive value at a cutoff value of 108.5. Our results showed that increased peripheral blood mtDNA copy number was associated with increased risk of RCC. Therefore, RCC might be considered as part of a range of potential tumors in cases with elevated blood mtDNA copy number.

  9. The Porcine TSPY Gene Is Tricopy but Not a Copy Number Variant.

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    Anh T Quach

    Full Text Available The testis-specific protein Y-encoded (TSPY gene is situated on the mammalian Y-chromosome and exhibits some remarkable biological characteristics. It has the highest known copy number (CN of all protein coding genes in the human and bovine genomes (up to 74 and 200, respectively and also shows high individual variability. Although the biological function of TSPY has not yet been elucidated, its specific expression in the testis and several identified binding domains within the protein suggests roles in male reproduction. Here we describe the porcine TSPY, as a multicopy gene with three copies located on the short arm of the Y-chromosome with no variation at three exon loci among 20 animals of normal reproductive health from four breeds of domestic pigs (Piétrain, Landrace, Duroc and Yorkshire. To further investigate the speculation that porcine TSPY is not a copy number variant, we have included five Low-fertility boars and five boars with exceptional High-fertility records. Interestingly, there was no difference between the High- and Low-fertile groups, but we detected slightly lower TSPY CN at all three exons (2.56-2.85 in both groups, as compared to normal animals, which could be attributed to technical variability or somatic mosaicism. The results are based on both relative quantitative real-time PCR (qPCR and droplet digital PCR (ddPCR. Chromosomal localization of the porcine TSPY was done using fluorescence in situ hybridization (FISH with gene specific PCR probes.

  10. Reduced mtDNA copy number increases the sensitivity of tumor cells to chemotherapeutic drugs.

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    Mei, H; Sun, S; Bai, Y; Chen, Y; Chai, R; Li, H

    2015-04-02

    Many cancer drugs are toxic to cells by activating apoptotic pathways. Previous studies have shown that mitochondria have key roles in apoptosis in mammalian cells, but the role of mitochondrial DNA (mtDNA) copy number variation in the pathogenesis of tumor cell apoptosis remains largely unknown. We used the HEp-2, HNE2, and A549 tumor cell lines to explore the relationship between mtDNA copy number variation and cell apoptosis. We first induced apoptosis in three tumor cell lines and one normal adult human skin fibroblast cell line (HSF) with cisplatin (DDP) or doxorubicin (DOX) treatment and found that the mtDNA copy number significantly increased in apoptotic tumor cells, but not in HSF cells. We then downregulated the mtDNA copy number by transfection with shRNA-TFAM plasmids or treatment with ethidium bromide and found that the sensitivity of tumor cells to DDP or DOX was significantly increased. Furthermore, we observed that levels of reactive oxygen species (ROS) increased significantly in tumor cells with lower mtDNA copy numbers, and this might be related to a low level of antioxidant gene expression. Finally, we rescued the increase of ROS in tumor cells with lipoic acid or N-acetyl-L-cysteine and found that the apoptosis rate decreased. Our studies suggest that the increase of mtDNA copy number is a self-protective mechanism of tumor cells to prevent apoptosis and that reduced mtDNA copy number increases ROS levels in tumor cells, increases the tumor cells' sensitivity to chemotherapeutic drugs, and increases the rate of apoptosis. This research provides evidence that mtDNA copy number variation might be a promising new therapeutic target for the clinical treatment of tumors.

  11. Reduced mtDNA copy number increases the sensitivity of tumor cells to chemotherapeutic drugs

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    Mei, H; Sun, S; Bai, Y; Chen, Y; Chai, R; Li, H

    2015-01-01

    Many cancer drugs are toxic to cells by activating apoptotic pathways. Previous studies have shown that mitochondria have key roles in apoptosis in mammalian cells, but the role of mitochondrial DNA (mtDNA) copy number variation in the pathogenesis of tumor cell apoptosis remains largely unknown. We used the HEp-2, HNE2, and A549 tumor cell lines to explore the relationship between mtDNA copy number variation and cell apoptosis. We first induced apoptosis in three tumor cell lines and one normal adult human skin fibroblast cell line (HSF) with cisplatin (DDP) or doxorubicin (DOX) treatment and found that the mtDNA copy number significantly increased in apoptotic tumor cells, but not in HSF cells. We then downregulated the mtDNA copy number by transfection with shRNA-TFAM plasmids or treatment with ethidium bromide and found that the sensitivity of tumor cells to DDP or DOX was significantly increased. Furthermore, we observed that levels of reactive oxygen species (ROS) increased significantly in tumor cells with lower mtDNA copy numbers, and this might be related to a low level of antioxidant gene expression. Finally, we rescued the increase of ROS in tumor cells with lipoic acid or N-acetyl-L-cysteine and found that the apoptosis rate decreased. Our studies suggest that the increase of mtDNA copy number is a self-protective mechanism of tumor cells to prevent apoptosis and that reduced mtDNA copy number increases ROS levels in tumor cells, increases the tumor cells' sensitivity to chemotherapeutic drugs, and increases the rate of apoptosis. This research provides evidence that mtDNA copy number variation might be a promising new therapeutic target for the clinical treatment of tumors. PMID:25837486

  12. CNVkit: Genome-Wide Copy Number Detection and Visualization from Targeted DNA Sequencing.

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    Eric Talevich

    2016-04-01

    Full Text Available Germline copy number variants (CNVs and somatic copy number alterations (SCNAs are of significant importance in syndromic conditions and cancer. Massively parallel sequencing is increasingly used to infer copy number information from variations in the read depth in sequencing data. However, this approach has limitations in the case of targeted re-sequencing, which leaves gaps in coverage between the regions chosen for enrichment and introduces biases related to the efficiency of target capture and library preparation. We present a method for copy number detection, implemented in the software package CNVkit, that uses both the targeted reads and the nonspecifically captured off-target reads to infer copy number evenly across the genome. This combination achieves both exon-level resolution in targeted regions and sufficient resolution in the larger intronic and intergenic regions to identify copy number changes. In particular, we successfully inferred copy number at equivalent to 100-kilobase resolution genome-wide from a platform targeting as few as 293 genes. After normalizing read counts to a pooled reference, we evaluated and corrected for three sources of bias that explain most of the extraneous variability in the sequencing read depth: GC content, target footprint size and spacing, and repetitive sequences. We compared the performance of CNVkit to copy number changes identified by array comparative genomic hybridization. We packaged the components of CNVkit so that it is straightforward to use and provides visualizations, detailed reporting of significant features, and export options for integration into existing analysis pipelines. CNVkit is freely available from https://github.com/etal/cnvkit.

  13. Genome-wide detection of copy number variations among diverse horse breeds by array CGH.

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    Wang, Wei; Wang, Shenyuan; Hou, Chenglin; Xing, Yanping; Cao, Junwei; Wu, Kaifeng; Liu, Chunxia; Zhang, Dong; Zhang, Li; Zhang, Yanru; Zhou, Huanmin

    2014-01-01

    Recent studies have found that copy number variations (CNVs) are widespread in human and animal genomes. CNVs are a significant source of genetic variation, and have been shown to be associated with phenotypic diversity. However, the effect of CNVs on genetic variation in horses is not well understood. In the present study, CNVs in 6 different breeds of mare horses, Mongolia horse, Abaga horse, Hequ horse and Kazakh horse (all plateau breeds) and Debao pony and Thoroughbred, were determined using aCGH. In total, seven hundred CNVs were identified ranging in size from 6.1 Kb to 0.57 Mb across all autosomes, with an average size of 43.08 Kb and a median size of 15.11 Kb. By merging overlapping CNVs, we found a total of three hundred and fifty-three CNV regions (CNVRs). The length of the CNVRs ranged from 6.1 Kb to 1.45 Mb with average and median sizes of 38.49 Kb and 13.1 Kb. Collectively, 13.59 Mb of copy number variation was identified among the horses investigated and accounted for approximately 0.61% of the horse genome sequence. Five hundred and eighteen annotated genes were affected by CNVs, which corresponded to about 2.26% of all horse genes. Through the gene ontology (GO), genetic pathway analysis and comparison of CNV genes among different breeds, we found evidence that CNVs involving 7 genes may be related to the adaptation to severe environment of these plateau horses. This study is the first report of copy number variations in Chinese horses, which indicates that CNVs are ubiquitous in the horse genome and influence many biological processes of the horse. These results will be helpful not only in mapping the horse whole-genome CNVs, but also to further research for the adaption to the high altitude severe environment for plateau horses.

  14. Detection of copy number variations and their effects in Chinese bulls

    KAUST Repository

    Zhang, Liangzhi

    2014-06-17

    Background: Copy number variations (CNVs) are a main source of genomic structural variations underlying animal evolution and production traits. Here, with one pure-blooded Angus bull as reference, we describe a genome-wide analysis of CNVs based on comparative genomic hybridization arrays in 29 Chinese domesticated bulls and examined their effects on gene expression and cattle growth traits.Results: We identified 486 copy number variable regions (CNVRs), covering 2.45% of the bovine genome, in 24 taurine (Bos taurus), together with 161 ones in 2 yaks (Bos grunniens) and 163 ones in 3 buffaloes (Bubalus bubalis). Totally, we discovered 605 integrated CNVRs, with more " loss" events than both " gain" and " both" ones, and clearly clustered them into three cattle groups. Interestingly, we confirmed their uneven distributions across chromosomes, and the differences of mitochondrion DNA copy number (gain: taurine, loss: yak & buffalo). Furthermore, we confirmed approximately 41.8% (253/605) and 70.6% (427/605) CNVRs span cattle genes and quantitative trait loci (QTLs), respectively. Finally, we confirmed 6 CNVRs in 9 chosen ones by using quantitative PCR, and further demonstrated that CNVR22 had significantly negative effects on expression of PLA2G2D gene, and both CNVR22 and CNVR310 were associated with body measurements in Chinese cattle, suggesting their key effects on gene expression and cattle traits.Conclusions: The results advanced our understanding of CNV as an important genomic structural variation in taurine, yak and buffalo. This study provides a highly valuable resource for Chinese cattle\\'s evolution and breeding researches. 2014 Zhang et al.; licensee BioMed Central Ltd.

  15. Telomere length is correlated with mitochondrial DNA copy number in intestinal, but not diffuse, gastric cancer.

    Science.gov (United States)

    Jung, Soo-Jung; Cho, Ji-Hyoung; Park, Won-Jin; Heo, Yu-Ran; Lee, Jae-Ho

    2017-07-01

    A positive correlation between telomere length and mitochondrial DNA (mtDNA) copy number has previously been observed in healthy individuals, and in patients with psychiatric disorders. In the present study, telomere length and mtDNA copy number were evaluated in gastric cancer (GC) tissue samples. DNA was extracted from 109 GC samples (including 82 intestinal, and 27 diffuse cases), and the telomere length and mtDNA copy number were analyzed using a quantitative-polymerase chain reaction assay. The relative telomere length and mtDNA copy number in tumor tissue, as compared with in normal tissue, (mean ± standard deviation) in all GC samples were 11.48±1.14 and 14.86±1.35, respectively. Telomere length and mtDNA copy number were not identified as exhibiting clinical or prognostic value for GC. However, positive correlations between telomere length and mitochondrial DNA copy number were identified in GC (r=0.408, P<0.001) and in the adjacent normal mucosa (r=0.363; P<0.001). When stratified by Lauren classification, the correlation was identified in intestinal type GC samples (r=0.461; P<0.001), but not in diffuse type GC samples (r=0.225; P=0.260). This result indicated that loss of the correlation of telomeres and mitochondrial function may induce the initiation or progression of GC pathogenesis.

  16. TOP1 gene copy numbers are increased in cancers of the bile duct and pancreas

    DEFF Research Database (Denmark)

    Grunnet, Mie; Calatayud, Dan; Schultz, Nicolai Aa.

    2015-01-01

    ) poison. Top1 protein, TOP1 gene copy number and mRNA expression, respectively, have been proposed as predictive biomarkers of response to irinotecan in other cancers. Here we investigate the occurrence of TOP1 gene aberrations in cancers of the bile ducts and pancreas. Material and methods. TOP1...... and centromere 20 (CEN-20) numbers were investigated by fluorescence in situ hybridization analyses in tumor tissue from 226 patients. The frequencies of aberration in the TOP1 gene copy number, the CEN-20 copy number and the TOP1/CEN-20 ratio were analyzed. As TOP1 is located on chromosome 20, the CEN-20 probe...... was included to distinguish between chromosomal and gene amplifications. Results. In PC, 29.8% had an increased TOP1 copy number (≥3.5n gene copies per cell) and 10.8% had a TOP1/CEN-20 ratio >1.5. In bile duct cancer, 12.8 % had an increased TOP1 copy number and 6.4% had a TOP1/CEN-20 ratio >1.5. Neither...

  17. Genomic copy number alterations of primary and secondary metastasizing pleomorphic adenomas.

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    Mariano, Fernanda Viviane; Gondak, Rogério de Oliveira; Martins, Antonio Santos; Coletta, Ricardo Della; Paes de Almeida, Oslei; Kowalski, Luiz Paulo; Krepischi, Ana Cristina Victorino; Altemani, Albina

    2015-09-01

    Metastasizing pleomorphic adenoma (MPA) is a rare tumour, and its mechanism of metastasis still is unknown. To date, there has been no study on MPA genomics. We analysed primary and secondary MPAs with array comparative genomic hybridization to identify somatic copy number alterations and affected genes. Tumour DNA samples from primary (parotid salivary gland) and secondary (scalp skin) MPAs were subjected to array comparative genomic hybridization investigation, and the data were analysed with NEXUS COPY NUMBER DISCOVERY. The primary MPA showed copy number losses affecting 3p22.2p14.3 and 19p13.3p123, and a complex pattern of four different deletions at chromosome 6. The 3p deletion encompassed several genes: CTNNB1, SETD2, BAP1, and PBRM1, among others. The secondary MPA showed a genomic profile similar to that of the primary MPA, with acquisition of additional copy number changes affecting 9p24.3p13.1 (loss), 19q11q13.43 (gain), and 22q11.1q13.33 (gain). Our findings indicated a clonal origin of the secondary MPA, as both tumours shared a common profile of genomic copy number alterations. Furthermore, we were able to detect in the primary tumour a specific pattern of copy number alterations that could explain the metastasizing characteristic, whereas the secondary MPA showed a more unbalanced genome. © 2015 John Wiley & Sons Ltd.

  18. Copy number analysis of ductal carcinoma in situ with and without recurrence.

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    Gorringe, Kylie L; Hunter, Sally M; Pang, Jia-Min; Opeskin, Ken; Hill, Prue; Rowley, Simone M; Choong, David Y H; Thompson, Ella R; Dobrovic, Alexander; Fox, Stephen B; Mann, G Bruce; Campbell, Ian G

    2015-09-01

    Ductal carcinoma in situ (DCIS) is a non-obligate precursor of invasive breast cancer and a frequent mammographic finding requiring treatment. Up to 25% of DCIS can recur and half of recurrences are invasive, but there are no reliable biomarkers for recurrence. We hypothesised that copy number aberrations could predict likelihood of recurrence. We analysed a cohort of pure DCIS cases treated only with wide local excision for genome-wide copy number and loss of heterozygosity using Affymetrix OncoScan MIP arrays. Cases included those without recurrence within 7 years (n = 25) and with recurrence between 1 and 5 years after diagnosis (n = 15). Pure DCIS were broadly similar in copy number changes compared with invasive breast cancer, with the consistent exception of a greater frequency of ERBB2 amplification in DCIS. There were no significant differences in age or ER status between the cases with a recurrence vs those without. Overall, the DCIS cases with recurrence had more copy number events than the DCIS without recurrence. The increased copy number appeared non-random with several genomic regions showing an increase in frequency in recurrent cases, including 20 q gain, ERBB2 amplification and 15q loss. Copy number changes may provide prognostic information for DCIS recurrence, but validation in additional cohorts is required.

  19. A novel technique for measuring variations in DNA copy-number: competitive genomic polymerase chain reaction

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    Nakagawara Akira

    2007-07-01

    Full Text Available Background Changes in genomic copy number occur in many human diseases including cancer. Characterization of these changes is important for both basic understanding and diagnosis of these diseases. Microarrays have recently become the standard technique and are commercially available. However, it is useful to have an affordable technique to complement them. Results We describe a novel polymerase chain reaction (PCR-based technique, termed competitive genomic PCR (CGP. The main characteristic of CGP is that different adaptors are added to the sample and control genomic DNAs after appropriate restriction enzyme digestion. These adaptor-supplemented DNAs are subjected to competitive PCR using an adaptor-primer and a locus-specific primer. The amplified products are then separated according to size differences between the adaptors. CGP eliminates the tedious steps inherent in quantitative PCR and achieves moderate throughput. Assays with different X chromosome numbers showed that it can provide accurate quantification. High-resolution analysis of neuroblastoma cell lines around the MYCN locus revealed novel junctions for amplification, which were not detected by a commercial array. Conclusion CGP is a moderate throughput technique for analyzing changes in genomic copy numbers. Because CGP can measure any genomic locus using PCR primers, it is especially useful for detailed analysis of a genomic region of interest.

  20. Chemiluminescent Detection for Estimating Relative Copy Numbers of Porcine Endogenous Retrovirus Proviruses from Chinese Minipigs Based on Magnetic Nanoparticles.

    Science.gov (United States)

    Yang, Haowen; Liu, Ming; Zhou, Bingcong; Deng, Yan; He, Nongyue; Jiang, Hesheng; Guo, Yafen; Lan, Ganqiu; Jiang, Qinyang; Yang, Xiurong; Li, Zhiyang

    2016-06-01

    Chinese Bama minipigs could be potential donors for the supply of xenografts because they are genetically stable, highly inbred, and inexpensive. However, porcine endogenous retrovirus (PERV) is commonly integrated in pig genomes and could cause a cross-species infection by xenotransplantation. For screening out the pigs with low copy numbers of PERV proviruses, we have developed a novel semiquantitative analysis approach based on magnetic nanoparticles (MNPs) and chemiluminescence (CL) for estimating relative copy numbers (RCNs) of PERV proviruses in Chinese Bama minipigs. The CL intensities of PERV proviruses and the housekeeping gene glyceraldehyde-3-phosphate dehydrogenase (GAPDH) were respectively determined with this method, and the RCNs of PERV proviruses were calculated by the equation: RCN of PERV provirus = CL intensity of PERV provirus/CL intensity of GAPDH. The results showed that PERVs were integrated in the genomes of Bama minipigs at different copy numbers, and the copy numbers of PERV-C subtype were greatly low. Two Bama minipigs with low copy numbers of PERV proviruses were detected out and could be considered as xenograft donor candidates. Although only semiquantitation can be achieved, this approach has potential for screening out safe and suitable pig donors for xenotransplantation.

  1. Between-species differences in gene copy number are enriched among functions critical for adaptive evolution in Arabidopsis halleri.

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    Suryawanshi, Vasantika; Talke, Ina N; Weber, Michael; Eils, Roland; Brors, Benedikt; Clemens, Stephan; Krämer, Ute

    2016-12-22

    Gene copy number divergence between species is a form of genetic polymorphism that contributes significantly to both genome size and phenotypic variation. In plants, copy number expansions of single genes were implicated in cultivar- or species-specific tolerance of high levels of soil boron, aluminium or calamine-type heavy metals, respectively. Arabidopsis halleri is a zinc- and cadmium-hyperaccumulating extremophile species capable of growing on heavy-metal contaminated, toxic soils. In contrast, its non-accumulating sister species A. lyrata and the closely related reference model species A. thaliana exhibit merely basal metal tolerance. For a genome-wide assessment of the role of copy number divergence (CND) in lineage-specific environmental adaptation, we conducted cross-species array comparative genome hybridizations of three plant species and developed a global signal scaling procedure to adjust for sequence divergence. In A. halleri, transition metal homeostasis functions are enriched twofold among the genes detected as copy number expanded. Moreover, biotic stress functions including mostly disease Resistance (R) gene-related genes are enriched twofold among genes detected as copy number reduced, when compared to the abundance of these functions among all genes. Our results provide genome-wide support for a link between evolutionary adaptation and CND in A. halleri as shown previously for Heavy metal ATPase4. Moreover our results support the hypothesis that elemental defences, which result from the hyperaccumulation of toxic metals, allow the reduction of classical defences against biotic stress as a trade-off.

  2. Clinical Omics Analysis of Colorectal Cancer Incorporating Copy Number Aberrations and Gene Expression Data

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    Tsuyoshi Yoshida

    2010-07-01

    Full Text Available Background: Colorectal cancer (CRC is one of the most frequently occurring cancers in Japan, and thus a wide range of methods have been deployed to study the molecular mechanisms of CRC. In this study, we performed a comprehensive analysis of CRC, incorporating copy number aberration (CRC and gene expression data. For the last four years, we have been collecting data from CRC cases and organizing the information as an “omics” study by integrating many kinds of analysis into a single comprehensive investigation. In our previous studies, we had experienced difficulty in finding genes related to CRC, as we observed higher noise levels in the expression data than in the data for other cancers. Because chromosomal aberrations are often observed in CRC, here, we have performed a combination of CNA analysis and expression analysis in order to identify some new genes responsible for CRC. This study was performed as part of the Clinical Omics Database Project at Tokyo Medical and Dental University. The purpose of this study was to investigate the mechanism of genetic instability in CRC by this combination of expression analysis and CNA, and to establish a new method for the diagnosis and treatment of CRC. Materials and methods: Comprehensive gene expression analysis was performed on 79 CRC cases using an Affymetrix Gene Chip, and comprehensive CNA analysis was performed using an Affymetrix DNA Sty array. To avoid the contamination of cancer tissue with normal cells, laser micro-dissection was performed before DNA/RNA extraction. Data analysis was performed using original software written in the R language. Result: We observed a high percentage of CNA in colorectal cancer, including copy number gains at 7, 8q, 13 and 20q, and copy number losses at 8p, 17p and 18. Gene expression analysis provided many candidates for CRC-related genes, but their association with CRC did not reach the level of statistical significance. The combination of CNA and gene

  3. Copy number variation in CNP267 region may be associated with hip bone size.

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    Shan-Lin Liu

    Full Text Available Osteoporotic hip fracture (HF is a serious global public health problem associated with high morbidity and mortality. Hip bone size (BS has been identified as one of key measurable risk factors for HF, independent of bone mineral density (BMD. Hip BS is highly genetically determined, but genetic factors underlying BS variation are still poorly defined. Here, we performed an initial genome-wide copy number variation (CNV association analysis for hip BS in 1,627 Chinese Han subjects using Affymetrix GeneChip Human Mapping SNP 6.0 Array and a follow-up replicate study in 2,286 unrelated US Caucasians sample. We found that a copy number polymorphism (CNP267 located at chromosome 2q12.2 was significantly associated with hip BS in both initial Chinese and replicate Caucasian samples with p values of 4.73E-03 and 5.66E-03, respectively. An important candidate gene, four and a half LIM domains 2 (FHL2, was detected at the downstream of CNP267, which plays important roles in bone metabolism by binding to several bone formation regulator, such as insulin-like growth factor-binding protein 5 (IGFBP-5 and androgen receptor (AR. Our findings suggest that CNP267 region may be associated with hip BS which might influence the FHL2 gene downstream.

  4. Genome-wide analysis of copy number variation in type 1 diabetes.

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    Britney L Grayson

    Full Text Available Type 1 diabetes (T1D tends to cluster in families, suggesting there may be a genetic component predisposing to disease. However, a recent large-scale genome-wide association study concluded that identified genetic factors, single nucleotide polymorphisms, do not account for overall familiality. Another class of genetic variation is the amplification or deletion of >1 kilobase segments of the genome, also termed copy number variations (CNVs. We performed genome-wide CNV analysis on a cohort of 20 unrelated adults with T1D and a control (Ctrl cohort of 20 subjects using the Affymetrix SNP Array 6.0 in combination with the Birdsuite copy number calling software. We identified 39 CNVs as enriched or depleted in T1D versus Ctrl. Additionally, we performed CNV analysis in a group of 10 monozygotic twin pairs discordant for T1D. Eleven of these 39 CNVs were also respectively enriched or depleted in the Twin cohort, suggesting that these variants may be involved in the development of islet autoimmunity, as the presently unaffected twin is at high risk for developing islet autoimmunity and T1D in his or her lifetime. These CNVs include a deletion on chromosome 6p21, near an HLA-DQ allele. CNVs were found that were both enriched or depleted in patients with or at high risk for developing T1D. These regions may represent genetic variants contributing to development of islet autoimmunity in T1D.

  5. DNA Copy Number Changes at 8q11–24 in Metastasized Colorectal Cancer

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    T. E. Buffart

    2005-01-01

    Full Text Available Background: C-Myc, a well-known oncogene located on 8q24.12–q24.23, is often amplified and over-expressed in both primary and metastasizing colorectal cancer. In addition, PRL-3 (also known as PTP4A3, a tyrosine phosphatase located on 8q24.3, is amplified in colorectal cancer metastasis. Beside PRL-3 and c-myc, other oncogenes located on the 8q23–24 region might be involved in this process. Therefore, the present study aims to correlate DNA copy number status of a series of genes at 8q23–24 in colorectal cancer at high resolution in correlation to metastatic disease. Materials and Methods: Thirty-two cases of colorectal cancer, 10 stage B1, 10 B2 and 12 D (Astler–Coller with their corresponding liver metastasis and one colorectal cell line (colo205, previously analyzed by array-CGH, were included in this study. A chromosome 8 specific MLPA probe mixture was used to analyze the presence of DNA copy number changes. The probe mixture contained 29 probes covering 25 genes on chromosome 8, as well as 6 control probes on other chromosomes. Results and Discussion: MLPA results obtained of the colo205 colorectal cell line were comparable with previous array-CGH results, thus validating the MLPA probe mixture. Astler–Coller B1 and B2 colorectal cancers differed significantly in DNA copy number of the genes, MOS (p = 0.04, MYC (p = 0.007, DDEF1 (p = 0.004, PTK2 (p = 0.02 and PTP4A3 (p = 0.04. When comparing these with Astler–Coller D primary tumors, significant differences were seen for several genes as well (MYC (p < 0.000, DDEF1 (p < 0.000, SLA (p < 0.000, PTK2 (p < 0.000, PTP4A3 (p = 0.002, and RECQL4 (p = 0.01. When comparing primary Astler–Coller D tumors and their corresponding liver metastases, a similar pattern of gains and losses was observed. Most of the liver metastases showed higher DNA copy number ratios than the corresponding primary tumors, but this difference was only significant for TPD52 (p = 0.02 and EIF3S6 (p = 0

  6. Association Between Copy Number Variations of TLR7 and Ocular Behçet's Disease in a Chinese Han Population.

    Science.gov (United States)

    Fang, Jing; Chen, Lu; Tang, Jihong; Hou, Shengping; Liao, Dan; Ye, Zi; Wang, Chaokui; Cao, Qinfeng; Kijlstra, Aize; Yang, Peizeng

    2015-02-03

    The purpose of this study was to test whether gene copy number variations (CNVs) of Toll-like receptors (TLRs) are associated with uveitis. Copy number variations of TLRs were detected by real-time PCR. The first stage of the study consisted of enrolling 400 Behçet's disease (BD) patients, 400 Vogt-Koyanagi-Harada syndrome patients, 400 patients with acute anterior uveitis associated with or without ankylosing spondylitis, and 600 healthy subjects. The second stage included another set of 578 BD patients and 1000 healthy controls. The frequencies of TLR gene copy number types (TLR1, TLR2, TLR3, TLR5, TLR6, TLR7, TLR9, TLR10) were compared among patients and controls by using the χ(2) test. Real-time PCR was used to detect mRNA expression from peripheral blood mononuclear cells (PBMCs) obtained from healthy controls following stimulation with the TLR7 agonist R848. Levels of TNF-α, IL-6, IL-1β, and IFN-β in culture supernatants were measured by ELISA. All TLRs tested, except for TLR7, had a gene copy number of two in more than 98% of individuals tested. In the first stage, we found a significantly increased frequency of more than one copy of TLR7 (located on the X chromosome) in male BD patients and more than two copies in female patients (correction of P value [PC] = 0.021; PC = 0.048, respectively). A second stage and combined study confirmed the association (PC = 1.14 × 10(-6); PC = 9.12 × 10(-5), respectively). TLR7 mRNA expression in PBMCs was increased in healthy male carriers having more than one copy of TLR7 or females having more than two copies following stimulation with R848 (P = 0.021, P = 0.006, respectively). No effect of the various TLR7 copies on the release of TNF-α, IL-6, IL-1β, and IFN-β could be detected. This study provides evidence that a high copy number of TLR7 confers risk for BD in a Chinese Han population. (http://www.chictr.org number, ChiCTR-CCC-12002184.). Copyright 2015 The Association for Research in Vision and Ophthalmology

  7. Copy-number and gene dependency analysis reveals partial copy loss of wild-type SF3B1 as a novel cancer vulnerability.

    Science.gov (United States)

    Paolella, Brenton R; Gibson, William J; Urbanski, Laura M; Alberta, John A; Zack, Travis I; Bandopadhayay, Pratiti; Nichols, Caitlin A; Agarwalla, Pankaj K; Brown, Meredith S; Lamothe, Rebecca; Yu, Yong; Choi, Peter S; Obeng, Esther A; Heckl, Dirk; Wei, Guo; Wang, Belinda; Tsherniak, Aviad; Vazquez, Francisca; Weir, Barbara A; Root, David E; Cowley, Glenn S; Buhrlage, Sara J; Stiles, Charles D; Ebert, Benjamin L; Hahn, William C; Reed, Robin; Beroukhim, Rameen

    2017-02-08

    Genomic instability is a hallmark of human cancer, and results in widespread somatic copy number alterations. We used a genome-scale shRNA viability screen in human cancer cell lines to systematically identify genes that are essential in the context of particular copy-number alterations (copy-number associated gene dependencies). The most enriched class of copy-number associated gene dependencies was CYCLOPS (Copy-number alterations Yielding Cancer Liabilities Owing to Partial losS) genes, and spliceosome components were the most prevalent. One of these, the pre-mRNA splicing factor SF3B1, is also frequently mutated in cancer. We validated SF3B1 as a CYCLOPS gene and found that human cancer cells harboring partial SF3B1 copy-loss lack a reservoir of SF3b complex that protects cells with normal SF3B1 copy number from cell death upon partial SF3B1 suppression. These data provide a catalog of copy-number associated gene dependencies and identify partial copy-loss of wild-type SF3B1 as a novel, non-driver cancer gene dependency.

  8. Identification of chloroquine resistance Pfcrt-K76T and determination of Pfmdr1-N86Y copy number by SYBR Green I qPCR

    Directory of Open Access Journals (Sweden)

    Addimas Tajebe

    2015-03-01

    Conclusions: The study showed high prevalence level and fixation of Pfcrt, 76T mutation after chloroquine withdrawal. The prevalence of Pfmdr1 copy number variant suggested that the presence of modulating factor for emergence of Plasmodium falciparum strains with higher copy numbers. However, the prevalence level was not statistically significant.

  9. HaplotypeCN: copy number haplotype inference with Hidden Markov Model and localized haplotype clustering.

    Directory of Open Access Journals (Sweden)

    Yen-Jen Lin

    Full Text Available Copy number variation (CNV has been reported to be associated with disease and various cancers. Hence, identifying the accurate position and the type of CNV is currently a critical issue. There are many tools targeting on detecting CNV regions, constructing haplotype phases on CNV regions, or estimating the numerical copy numbers. However, none of them can do all of the three tasks at the same time. This paper presents a method based on Hidden Markov Model to detect parent specific copy number change on both chromosomes with signals from SNP arrays. A haplotype tree is constructed with dynamic branch merging to model the transition of the copy number status of the two alleles assessed at each SNP locus. The emission models are constructed for the genotypes formed with the two haplotypes. The proposed method can provide the segmentation points of the CNV regions as well as the haplotype phasing for the allelic status on each chromosome. The estimated copy numbers are provided as fractional numbers, which can accommodate the somatic mutation in cancer specimens that usually consist of heterogeneous cell populations. The algorithm is evaluated on simulated data and the previously published regions of CNV of the 270 HapMap individuals. The results were compared with five popular methods: PennCNV, genoCN, COKGEN, QuantiSNP and cnvHap. The application on oral cancer samples demonstrates how the proposed method can facilitate clinical association studies. The proposed algorithm exhibits comparable sensitivity of the CNV regions to the best algorithm in our genome-wide study and demonstrates the highest detection rate in SNP dense regions. In addition, we provide better haplotype phasing accuracy than similar approaches. The clinical association carried out with our fractional estimate of copy numbers in the cancer samples provides better detection power than that with integer copy number states.

  10. A prospective study of mitochondrial DNA copy number and the risk of prostate cancer.

    Science.gov (United States)

    Moore, Amy; Lan, Qing; Hofmann, Jonathan N; Liu, Chin-San; Cheng, Wen-Ling; Lin, Ta-Tsung; Berndt, Sonja I

    2017-06-01

    Evidence suggests that mitochondrial DNA (mtDNA) copy number increases in response to DNA damage. Increased mtDNA copy number has been observed in prostate cancer (PCa) cells, suggesting a role in PCa development, but this association has not yet been investigated prospectively. We conducted a nested case-control study (793 cases and 790 controls) of men randomized to the screening arm of the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO) to evaluate the association between pre-diagnosis mtDNA copy number, measured in peripheral blood leukocytes, and the risk of PCa. We used logistic regression to estimate odds ratios (OR) and 95% confidence intervals (CI) and polytomous logistic regression to analyze differences in associations by non-aggressive (Stage I/II AND Gleason grade copy number was not significantly associated with PCa risk overall (OR 1.23, 95% CI 0.97-1.55, p = 0.089), increasing mtDNA copy number was associated with an increased risk of non-aggressive PCa (OR 1.29, 95% CI 1.01-1.65, p = 0.044) compared to controls. No association was observed with aggressive PCa (OR 1.02, 95% CI 0.64-1.63, p = 0.933). Higher mtDNA copy number was also associated with increased PSA levels among controls (p = 0.014). These results suggest that alterations in mtDNA copy number may reflect disruption of the normal prostate glandular architecture seen in early-stage disease, as opposed to reflecting the large number of tumor cells seen with advanced PCa.

  11. HaplotypeCN: Copy Number Haplotype Inference with Hidden Markov Model and Localized Haplotype Clustering

    Science.gov (United States)

    Lin, Yen-Jen; Chen, Yu-Tin; Hsu, Shu-Ni; Peng, Chien-Hua; Tang, Chuan-Yi; Yen, Tzu-Chen; Hsieh, Wen-Ping

    2014-01-01

    Copy number variation (CNV) has been reported to be associated with disease and various cancers. Hence, identifying the accurate position and the type of CNV is currently a critical issue. There are many tools targeting on detecting CNV regions, constructing haplotype phases on CNV regions, or estimating the numerical copy numbers. However, none of them can do all of the three tasks at the same time. This paper presents a method based on Hidden Markov Model to detect parent specific copy number change on both chromosomes with signals from SNP arrays. A haplotype tree is constructed with dynamic branch merging to model the transition of the copy number status of the two alleles assessed at each SNP locus. The emission models are constructed for the genotypes formed with the two haplotypes. The proposed method can provide the segmentation points of the CNV regions as well as the haplotype phasing for the allelic status on each chromosome. The estimated copy numbers are provided as fractional numbers, which can accommodate the somatic mutation in cancer specimens that usually consist of heterogeneous cell populations. The algorithm is evaluated on simulated data and the previously published regions of CNV of the 270 HapMap individuals. The results were compared with five popular methods: PennCNV, genoCN, COKGEN, QuantiSNP and cnvHap. The application on oral cancer samples demonstrates how the proposed method can facilitate clinical association studies. The proposed algorithm exhibits comparable sensitivity of the CNV regions to the best algorithm in our genome-wide study and demonstrates the highest detection rate in SNP dense regions. In addition, we provide better haplotype phasing accuracy than similar approaches. The clinical association carried out with our fractional estimate of copy numbers in the cancer samples provides better detection power than that with integer copy number states. PMID:24849202

  12. Identification of chloroquine resistance Pfcrt-K76T and determination of Pfmdr1-N86Y copy number by SYBR Green I qPCR

    Institute of Scientific and Technical Information of China (English)

    Addimas; Tajebe; Mulugeta; Aemero; Kimani; Francis; Gabriel; Magoma

    2015-01-01

    Objective:To identify prevalence of chloroquine resistance point mutation at(Pfcrt,K76T)and(Pfindr1.N86Y) copy number variation.Methods:SYBR Green I based real time PCR was used.One hundred and thirty-three samples were analyzed for(Pfcrt,K76T) and(Pfmdr1.N86Y) copy number from dried blood spot.Parasite DNA was extracted using high pure DNA preparation kit.The amplification of DNA was done by using AccuPower 2* GreenStar ’’ qPCR Master mix.For quantification purpose a new primer pair was designed for 178 base pair template from complete genome sequence of Plasmodium falciparum strain 3D7 at NCBI.Absolute quantification method was used to determine the Pfmdr1-N86 Y copy number variations.Standard curve was built from strain3D7 gDNA since it has single copy of Pfindr1 per haploid genome.The known positive controls with single and multi-copy number of Pfindr1 gene were included in each experiment.The copy number ratio of the samples to the standard calibrator was made to obtain the fold difference among the samples with respect to copy number variation.Results:Out of 133 samples 73(54.89%) were confirmed as mutant(Pfcrt,76T) and the remaining 60(45.11%) were genotyped as wild type(Pfcrt,K76).The(Pfindr1.N86Y) copy number variation was determined for 133 clinical samples.Out of these samples 61(45.86%)had single copy and the remaining 72(54.14%) had multi-copy numbers higher than 1.5 copies per genome.Thirty-four(25.56%) multi-copies were between 1.5 and 2.5 copies per genome while 38(28.57%) were more than 2.5 copies per genome.The minimum and maximum copies per genome were 0.474 and 4.741.respectively.Conclusions:The study showed high prevalence level and fixation of Pfcrt.76 T mutation after chloroquine withdrawal.The prevalence of Pfindr1 copy number variant suggested that the presence of modulating factor for emergence of Plasmodium falciparum strains with higher copy numbers.However,the prevalence level was not statistically significant.

  13. Association between Leukocyte Mitochondrial DNA Copy Number and Regular Exercise in Postmenopausal Women.

    Science.gov (United States)

    Chang, Yu Kyung; Kim, Da Eun; Cho, Soo Hyun; Kim, Jung-Ha

    2016-11-01

    Previous studies suggest that habitual exercise can improve skeletal mitochondrial function; however, to date, the association between exercise and mitochondrial function in peripheral leukocytes has not been reported. The aim of this study was to evaluate the relationship between regular exercise and mitochondrial function by measuring leukocyte mitochondrial DNA (mtDNA) copy number in postmenopausal women. This cross-sectional study included 144 relatively healthy, non-diabetic, non-smoking, postmenopausal women. Clinical parameters, including anthropometric measurements and cardio-metabolic parameters, were assessed. Regular exercise was defined as at least 150 minutes per week of moderate-intensity activity, or an equivalent combination of moderate and vigorous-intensity activity, over a duration of at least 6 months. Leukocyte mtDNA copy numbers were measured using real-time polymerase chain reaction assays, and these were normalized to the β-globin copy number to give the relative mtDNA copy number. The mtDNA copy number of peripheral leukocytes was significantly greater in the exercise group (1.33±0.02) than in the no exercise group (1.05±0.02, Pcopy number (β=0.25, Pcopy number in postmenopausal women.

  14. EGFR expression and copy number changes in low T-stage oral squamous cell carcinomas.

    Science.gov (United States)

    Rössle, Matthias; Weber, Claudia S; Züllig, Lena; Graf, Nicole; Jochum, Wolfram; Stöckli, Sandro J; Moch, Holger; Huber, Gerhard F

    2013-08-01

    EGFR-directed therapies are used to treat patients with advanced head and neck squamous cell carcinoma (SCC). As it is still unclear whether or not EGFR amplification represents an early or late event in head and neck SCC progression, we aimed to determine the frequency of abnormalities of EGFR protein and gene copy numbers in early oral SCC. A tissue microarray of cancer tissue from 120 patients with pT1/2 oral SCC was constructed. We investigated EGFR protein expression by immunohistochemistry. EGFR gene copy enumeration was performed using fluorescence in-situ hybridization (FISH) and the novel automated silver in-situ hybridization (SISH) technology. Of early oral SCC, 19.3% showed high, 57.1% moderate and 23.6% low EGFR expression. EGFR amplification/polysomy was identified in 8% and 9% of cases by FISH and SISH, respectively. EGFR-SISH had a high concordance with EGFR-FISH (kappa value = 1.0), and both methods showed high conformity with EGFR immunohistochemistry (P = 0.001 and P = 0.006, respectively). No correlation was found of EGFR protein expression or gene amplification status with pT or pN stage. Only a small subgroup of early oral SCC is characterized by EGFR amplification, which can be identified reliably using EGFR-SISH technology. This finding suggests that EGFR gene amplification mostly occurs in advanced stages of oral SCC. © 2013 John Wiley & Sons Ltd.

  15. iGC-an integrated analysis package of gene expression and copy number alteration.

    Science.gov (United States)

    Lai, Yi-Pin; Wang, Liang-Bo; Wang, Wei-An; Lai, Liang-Chuan; Tsai, Mong-Hsun; Lu, Tzu-Pin; Chuang, Eric Y

    2017-01-14

    With the advancement in high-throughput technologies, researchers can simultaneously investigate gene expression and copy number alteration (CNA) data from individual patients at a lower cost. Traditional analysis methods analyze each type of data individually and integrate their results using Venn diagrams. Challenges arise, however, when the results are irreproducible and inconsistent across multiple platforms. To address these issues, one possible approach is to concurrently analyze both gene expression profiling and CNAs in the same individual. We have developed an open-source R/Bioconductor package (iGC). Multiple input formats are supported and users can define their own criteria for identifying differentially expressed genes driven by CNAs. The analysis of two real microarray datasets demonstrated that the CNA-driven genes identified by the iGC package showed significantly higher Pearson correlation coefficients with their gene expression levels and copy numbers than those genes located in a genomic region with CNA. Compared with the Venn diagram approach, the iGC package showed better performance. The iGC package is effective and useful for identifying CNA-driven genes. By simultaneously considering both comparative genomic and transcriptomic data, it can provide better understanding of biological and medical questions. The iGC package's source code and manual are freely available at https://www.bioconductor.org/packages/release/bioc/html/iGC.html .

  16. Functional impact of global rare copy number variation in autism spectrum disorders.

    Science.gov (United States)

    Pinto, Dalila; Pagnamenta, Alistair T; Klei, Lambertus; Anney, Richard; Merico, Daniele; Regan, Regina; Conroy, Judith; Magalhaes, Tiago R; Correia, Catarina; Abrahams, Brett S; Almeida, Joana; Bacchelli, Elena; Bader, Gary D; Bailey, Anthony J; Baird, Gillian; Battaglia, Agatino; Berney, Tom; Bolshakova, Nadia; Bölte, Sven; Bolton, Patrick F; Bourgeron, Thomas; Brennan, Sean; Brian, Jessica; Bryson, Susan E; Carson, Andrew R; Casallo, Guillermo; Casey, Jillian; Chung, Brian H Y; Cochrane, Lynne; Corsello, Christina; Crawford, Emily L; Crossett, Andrew; Cytrynbaum, Cheryl; Dawson, Geraldine; de Jonge, Maretha; Delorme, Richard; Drmic, Irene; Duketis, Eftichia; Duque, Frederico; Estes, Annette; Farrar, Penny; Fernandez, Bridget A; Folstein, Susan E; Fombonne, Eric; Freitag, Christine M; Gilbert, John; Gillberg, Christopher; Glessner, Joseph T; Goldberg, Jeremy; Green, Andrew; Green, Jonathan; Guter, Stephen J; Hakonarson, Hakon; Heron, Elizabeth A; Hill, Matthew; Holt, Richard; Howe, Jennifer L; Hughes, Gillian; Hus, Vanessa; Igliozzi, Roberta; Kim, Cecilia; Klauck, Sabine M; Kolevzon, Alexander; Korvatska, Olena; Kustanovich, Vlad; Lajonchere, Clara M; Lamb, Janine A; Laskawiec, Magdalena; Leboyer, Marion; Le Couteur, Ann; Leventhal, Bennett L; Lionel, Anath C; Liu, Xiao-Qing; Lord, Catherine; Lotspeich, Linda; Lund, Sabata C; Maestrini, Elena; Mahoney, William; Mantoulan, Carine; Marshall, Christian R; McConachie, Helen; McDougle, Christopher J; McGrath, Jane; McMahon, William M; Merikangas, Alison; Migita, Ohsuke; Minshew, Nancy J; Mirza, Ghazala K; Munson, Jeff; Nelson, Stanley F; Noakes, Carolyn; Noor, Abdul; Nygren, Gudrun; Oliveira, Guiomar; Papanikolaou, Katerina; Parr, Jeremy R; Parrini, Barbara; Paton, Tara; Pickles, Andrew; Pilorge, Marion; Piven, Joseph; Ponting, Chris P; Posey, David J; Poustka, Annemarie; Poustka, Fritz; Prasad, Aparna; Ragoussis, Jiannis; Renshaw, Katy; Rickaby, Jessica; Roberts, Wendy; Roeder, Kathryn; Roge, Bernadette; Rutter, Michael L; Bierut, Laura J; Rice, John P; Salt, Jeff; Sansom, Katherine; Sato, Daisuke; Segurado, Ricardo; Sequeira, Ana F; Senman, Lili; Shah, Naisha; Sheffield, Val C; Soorya, Latha; Sousa, Inês; Stein, Olaf; Sykes, Nuala; Stoppioni, Vera; Strawbridge, Christina; Tancredi, Raffaella; Tansey, Katherine; Thiruvahindrapduram, Bhooma; Thompson, Ann P; Thomson, Susanne; Tryfon, Ana; Tsiantis, John; Van Engeland, Herman; Vincent, John B; Volkmar, Fred; Wallace, Simon; Wang, Kai; Wang, Zhouzhi; Wassink, Thomas H; Webber, Caleb; Weksberg, Rosanna; Wing, Kirsty; Wittemeyer, Kerstin; Wood, Shawn; Wu, Jing; Yaspan, Brian L; Zurawiecki, Danielle; Zwaigenbaum, Lonnie; Buxbaum, Joseph D; Cantor, Rita M; Cook, Edwin H; Coon, Hilary; Cuccaro, Michael L; Devlin, Bernie; Ennis, Sean; Gallagher, Louise; Geschwind, Daniel H; Gill, Michael; Haines, Jonathan L; Hallmayer, Joachim; Miller, Judith; Monaco, Anthony P; Nurnberger, John I; Paterson, Andrew D; Pericak-Vance, Margaret A; Schellenberg, Gerard D; Szatmari, Peter; Vicente, Astrid M; Vieland, Veronica J; Wijsman, Ellen M; Scherer, Stephen W; Sutcliffe, James S; Betancur, Catalina

    2010-07-15

    The autism spectrum disorders (ASDs) are a group of conditions characterized by impairments in reciprocal social interaction and communication, and the presence of restricted and repetitive behaviours. Individuals with an ASD vary greatly in cognitive development, which can range from above average to intellectual disability. Although ASDs are known to be highly heritable ( approximately 90%), the underlying genetic determinants are still largely unknown. Here we analysed the genome-wide characteristics of rare (<1% frequency) copy number variation in ASD using dense genotyping arrays. When comparing 996 ASD individuals of European ancestry to 1,287 matched controls, cases were found to carry a higher global burden of rare, genic copy number variants (CNVs) (1.19 fold, P = 0.012), especially so for loci previously implicated in either ASD and/or intellectual disability (1.69 fold, P = 3.4 x 10(-4)). Among the CNVs there were numerous de novo and inherited events, sometimes in combination in a given family, implicating many novel ASD genes such as SHANK2, SYNGAP1, DLGAP2 and the X-linked DDX53-PTCHD1 locus. We also discovered an enrichment of CNVs disrupting functional gene sets involved in cellular proliferation, projection and motility, and GTPase/Ras signalling. Our results reveal many new genetic and functional targets in ASD that may lead to final connected pathways.

  17. Identification of copy number alterations associated with the progression of DCIS to invasive ductal carcinoma.

    Science.gov (United States)

    Johnson, Clint E; Gorringe, Kylie L; Thompson, Ella R; Opeskin, Ken; Boyle, Samantha E; Wang, Yuker; Hill, Prue; Mann, G Bruce; Campbell, Ian G

    2012-06-01

    Ductal carcinoma in situ (DCIS) is a non-obligate precursor to invasive ductal carcinoma (IDC). Annotation of the genetic differences between the two lesions may assist in the identification of genes that promote the invasive phenotype. Synchronous DCIS and IDC cells were microdissected from FFPE tissue and analysed by molecular inversion probe (MIP) copy number arrays. Matched IDC and DCIS showed highly similar copy number profiles (average of 83% of the genome shared) indicating a common clonal origin although there is evidence that the DCIS continues to evolve in parallel with the co-existing IDC. Four chromosomal regions of loss (3q, 6q, 8p and 11q) and four regions of gain (5q, 16p, 19q and 20) were recurrently affected in IDC but not in DCIS. CCND1 and MYC showed increased amplitude of gain in IDC. One region of loss (17p11.2) was specific to DCIS. IDC-specific regions include genes with previous links to breast cancer progression and potential therapeutic targets such as AXL, SPHK1 and PLAUR.

  18. Association of nsv823469 copy number loss with decreased risk of chronic obstructive pulmonary disease and pulmonary function in Chinese.

    Science.gov (United States)

    Chen, Xiaoliang; Lu, Xiaoxiao; Chen, Jiansong; Wu, Di; Qiu, Fuman; Xiong, Huali; Pan, Zihua; Yang, Lei; Yang, Binyao; Xie, Chenli; Zhou, Yifeng; Huang, Dongsheng; Zhou, Yumin; Lu, Jiachun

    2017-01-12

    It is highly possible that copy number variations (CNVs) in susceptible regions have effects on chronic obstructive pulmonary disease (COPD) development, while long noncoding RNA (lncRNAs) have been shown to cause COPD. We hypothesized that the common CNV, named nsv823469 located on 6p22.1, and covering lncRNAs (major histocompatibility complex, class I, A (HLA-A) and HLA complex group 4B (HCG4B)) has an effect on COPD risk. This association was assessed through a two-stage case-control study, and was further confirmed with COPD and pulmonary function-based family analyses, respectively. The copy number loss (0-copy/1-copy) of nsv823469 significantly decreased risk of COPD compared with normal (2-copy) (OR = 0.77, 95% CI = 0.69-0.85). The loss allele, inducing copy number loss of nsv823469, has a tendency to transmit to offspring or siblings (P = 0.010) and is associated with forced expiratory volume in 1 second (FEV1) (P = 0.030). Furthermore, the copy number loss of nsv823469 in normal pulmonary tissue decreases the expression levels of HCG4B (r = 0.315, P = 0.031) and HLA-A (r = 0.296, P = 0.044). Our data demonstrates that nsv823469 plays a role in COPD and pulmonary function inheritance by potentially altering expression of HCG4B.

  19. Modulation of Mitochondrial DNA Copy Number to Induce Hepatocytic Differentiation of Human Amniotic Epithelial Cells.

    Science.gov (United States)

    Vaghjiani, Vijesh; Cain, Jason E; Lee, William; Vaithilingam, Vijayaganapathy; Tuch, Bernard E; St John, Justin C

    2017-09-05

    Mitochondrial deoxyribonucleic acid (mtDNA) copy number is tightly regulated during pluripotency and differentiation. There is increased demand of cellular adenosine triphosphate (ATP) during differentiation for energy-intensive cell types such as hepatocytes and neurons to meet the cell's functional requirements. During hepatocyte differentiation, mtDNA copy number should be synchronously increased to generate sufficient ATP through oxidative phosphorylation. Unlike bone marrow mesenchymal cells, mtDNA copy number failed to increase by 28 days of differentiation of human amniotic epithelial cells (hAEC) into hepatocyte-like cells (HLC) despite their expression of some end-stage hepatic markers. This was due to higher levels of DNA methylation at exon 2 of POLGA, the mtDNA-specific replication factor. Treatment with a DNA demethylation agent, 5-azacytidine, resulted in increased mtDNA copy number, reduced DNA methylation at exon 2 of POLGA, and reduced hepatic gene expression. Depletion of mtDNA followed by subsequent differentiation did not increase mtDNA copy number, but reduced DNA methylation at exon 2 of POLGA and increased expression of hepatic and pluripotency genes. We encapsulated hAEC in barium alginate microcapsules and subsequently differentiated them into HLC. Encapsulation resulted in no net increase of mtDNA copy number but a significant reduction in DNA methylation of POLGA. RNAseq analysis showed that differentiated HLC express hepatocyte-specific genes but also increased expression of inflammatory interferon genes. Differentiation in encapsulated cells showed suppression of inflammatory genes as well as increased expression of genes associated with hepatocyte function pathways and networks. This study demonstrates that an increase in classical hepatic gene expression can be achieved in HLC through encapsulation, although they fail to effectively regulate mtDNA copy number.

  20. Comparative analysis of copy number detection by whole-genome BAC and oligonucleotide array CGH

    Directory of Open Access Journals (Sweden)

    Bejjani Bassem A

    2010-06-01

    Full Text Available Abstract Background Microarray-based comparative genomic hybridization (aCGH is a powerful diagnostic tool for the detection of DNA copy number gains and losses associated with chromosome abnormalities, many of which are below the resolution of conventional chromosome analysis. It has been presumed that whole-genome oligonucleotide (oligo arrays identify more clinically significant copy-number abnormalities than whole-genome bacterial artificial chromosome (BAC arrays, yet this has not been systematically studied in a clinical diagnostic setting. Results To determine the difference in detection rate between similarly designed BAC and oligo arrays, we developed whole-genome BAC and oligonucleotide microarrays and validated them in a side-by-side comparison of 466 consecutive clinical specimens submitted to our laboratory for aCGH. Of the 466 cases studied, 67 (14.3% had a copy-number imbalance of potential clinical significance detectable by the whole-genome BAC array, and 73 (15.6% had a copy-number imbalance of potential clinical significance detectable by the whole-genome oligo array. However, because both platforms identified copy number variants of unclear clinical significance, we designed a systematic method for the interpretation of copy number alterations and tested an additional 3,443 cases by BAC array and 3,096 cases by oligo array. Of those cases tested on the BAC array, 17.6% were found to have a copy-number abnormality of potential clinical significance, whereas the detection rate increased to 22.5% for the cases tested by oligo array. In addition, we validated the oligo array for detection of mosaicism and found that it could routinely detect mosaicism at levels of 30% and greater. Conclusions Although BAC arrays have faster turnaround times, the increased detection rate of oligo arrays makes them attractive for clinical cytogenetic testing.

  1. Performance of Molecular Inversion Probes (MIP) in Allele CopyNumber Determination

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yuker; Moorhead, Martin; Karlin-Neumann, George; Wang,Nicolas J.; Ireland, James; Lin, Steven; Chen, Chunnuan; Heiser, LauraM.; Chin, Koei; Esserman, Laura; Gray, Joe W.; Spellman, Paul T.; Faham,Malek

    2007-05-14

    We have developed a new protocol for using MolecularInversion Probes (MIP) to accurately and specifically measure allele copynumber (ACN). The new protocol provides for significant improvementsincluding the reduction of input DNA (from 2?g) by more than 25 fold (to75ng total genomic DNA), higher overall precision resulting in one orderof magnitude lower false positive rate, and greater dynamic range withaccurate absolute copy number up to 60 copies.

  2. Simple screening method for copy number variations associated with physical features.

    Science.gov (United States)

    Ueki, Misuzu; Takeshita, Haruo; Fujihara, Junko; Kimura-Kataoka, Kaori; Iida, Reiko; Yasuda, Toshihiro

    2017-03-01

    Recent studies of copy number variations (CNVs) associated with physical features, such as body mass index, body height or bone length, have suggested that such CNVs could serve as markers in forensic cases involving unidentified individuals. However, the process of cataloging CNVs has been slow because of the cumbersome nature and low reliability of the procedures involved. Here we describe a simple quantitative real-time PCR (Q-PCR) method for screening of medicolegally useful CNVs, which does not require reference DNA with known copy number. The first step is to prepare a chimeric plasmid vector including one copy each of the single-copy gene-specific sequence as the internal standard, and the target CNV-specific sequence. To assess the validity of this new method, we analyzed CNVs in the LTBP1 and ETV6 gene regions, both of which are candidate CNVs associated with body height. The PCR efficiencies for the single-copy (reference) gene and the target CNV were similar, indicating that quantitation was reliable. Furthermore, simulated analysis of the LTBP1 CNV using mock samples prepared by mixing vectors in varying proportions showed that this analytical method allowed correct determination of the LTBP1 copy number. These results demonstrated that our simple method has considerable potential for screening of trait-related CNVs that would be useful for forensic casework. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Array-based comparative genomic hybridization for genome-wide screening of DNA copy number in bladder tumors.

    NARCIS (Netherlands)

    Veltman, J.A.; Fridlyand, J.; Pejavar, S.; Olshen, A.B.; Korkola, J.E.; Vries, S. de; Carroll, P.; Kuo, W.L.; Pinkel, D.; Albertson, D.; Cordon-Cardo, C.; Jain, A.N.; Waldman, F.M.

    2003-01-01

    Genome-wide copy number profiles were characterized in 41 primary bladder tumors using array-based comparative genomic hybridization (array CGH). In addition to previously identified alterations in large chromosomal regions, alterations were identified in many small genomic regions, some with high-l

  4. A Hidden Markov Model to estimate population mixture and allelic copy-numbers in cancers using Affymetrix SNP arrays

    Directory of Open Access Journals (Sweden)

    Torring Niels

    2007-11-01

    Full Text Available Abstract Background Affymetrix SNP arrays can interrogate thousands of SNPs at the same time. This allows us to look at the genomic content of cancer cells and to investigate the underlying events leading to cancer. Genomic copy-numbers are today routinely derived from SNP array data, but the proposed algorithms for this task most often disregard the genotype information available from germline cells in paired germline-tumour samples. Including this information may deepen our understanding of the "true" biological situation e.g. by enabling analysis of allele specific copy-numbers. Here we rely on matched germline-tumour samples and have developed a Hidden Markov Model (HMM to estimate allelic copy-number changes in tumour cells. Further with this approach we are able to estimate the proportion of normal cells in the tumour (mixture proportion. Results We show that our method is able to recover the underlying copy-number changes in simulated data sets with high accuracy (above 97.71%. Moreover, although the known copy-numbers could be well recovered in simulated cancer samples with more than 70% cancer cells (and less than 30% normal cells, we demonstrate that including the mixture proportion in the HMM increases the accuracy of the method. Finally, the method is tested on HapMap samples and on bladder and prostate cancer samples. Conclusion The HMM method developed here uses the genotype calls of germline DNA and the allelic SNP intensities from the tumour DNA to estimate allelic copy-numbers (including changes in the tumour. It differentiates between different events like uniparental disomy and allelic imbalances. Moreover, the HMM can estimate the mixture proportion, and thus inform about the purity of the tumour sample.

  5. Cardiometabolic phenotypes and mitochondrial DNA copy number in two cohorts of UK women.

    Science.gov (United States)

    Guyatt, Anna L; Burrows, Kimberley; Guthrie, Philip A I; Ring, Sue; McArdle, Wendy; Day, Ian N M; Ascione, Raimondo; Lawlor, Debbie A; Gaunt, Tom R; Rodriguez, Santiago

    2017-08-15

    The mitochondrial genome is present at variable copy number between individuals. Mitochondria are vulnerable to oxidative stress, and their dysfunction may be associated with cardiovascular disease. The association of mitochondrial DNA copy number with cardiometabolic risk factors (lipids, glycaemic traits, inflammatory markers, anthropometry and blood pressure) was assessed in two independent cohorts of European origin women, one in whom outcomes were measured at mean (SD) age 30 (4.3) years (N=2278) and the second at 69.4 (5.5) years (N=2872). Mitochondrial DNA copy number was assayed by quantitative polymerase chain reaction. Associations were adjusted for smoking, sociodemographic status, laboratory factors and white cell traits. Out of a total of 12 outcomes assessed in both cohorts, mitochondrial DNA copy number showed little or no association with the majority (point estimates were close to zero and nearly all p-values were >0.01). The strongest evidence was for an inverse association in the older cohort with insulin (standardised beta [95%CI]: -0.06, [-0.098, -0.022], p=0.002), but this association did not replicate in the younger cohort. Our findings do not provide support for variation in mitochondrial DNA copy number having an important impact on cardio-metabolic risk factors in European origin women. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  6. Dietary Variation and Evolution of Gene Copy Number among Dog Breeds.

    Science.gov (United States)

    Reiter, Taylor; Jagoda, Evelyn; Capellini, Terence D

    2016-01-01

    Prolonged human interactions and artificial selection have influenced the genotypic and phenotypic diversity among dog breeds. Because humans and dogs occupy diverse habitats, ecological contexts have likely contributed to breed-specific positive selection. Prior to the advent of modern dog-feeding practices, there was likely substantial variation in dietary landscapes among disparate dog breeds. As such, we investigated one type of genetic variant, copy number variation, in three metabolic genes: glucokinase regulatory protein (GCKR), phytanol-CoA 2-hydroxylase (PHYH), and pancreatic α-amylase 2B (AMY2B). These genes code for proteins that are responsible for metabolizing dietary products that originate from distinctly different food types: sugar, meat, and starch, respectively. After surveying copy number variation among dogs with diverse dietary histories, we found no correlation between diet and positive selection in either GCKR or PHYH. Although it has been previously demonstrated that dogs experienced a copy number increase in AMY2B relative to wolves during or after the dog domestication process, we demonstrate that positive selection continued to act on amylase copy number in dog breeds that consumed starch-rich diets in time periods after domestication. Furthermore, we found that introgression with wolves is not responsible for deterioration of positive selection on AMY2B among diverse dog breeds. Together, this supports the hypothesis that the amylase copy number expansion is found universally in dogs.

  7. Dietary Variation and Evolution of Gene Copy Number among Dog Breeds.

    Directory of Open Access Journals (Sweden)

    Taylor Reiter

    Full Text Available Prolonged human interactions and artificial selection have influenced the genotypic and phenotypic diversity among dog breeds. Because humans and dogs occupy diverse habitats, ecological contexts have likely contributed to breed-specific positive selection. Prior to the advent of modern dog-feeding practices, there was likely substantial variation in dietary landscapes among disparate dog breeds. As such, we investigated one type of genetic variant, copy number variation, in three metabolic genes: glucokinase regulatory protein (GCKR, phytanol-CoA 2-hydroxylase (PHYH, and pancreatic α-amylase 2B (AMY2B. These genes code for proteins that are responsible for metabolizing dietary products that originate from distinctly different food types: sugar, meat, and starch, respectively. After surveying copy number variation among dogs with diverse dietary histories, we found no correlation between diet and positive selection in either GCKR or PHYH. Although it has been previously demonstrated that dogs experienced a copy number increase in AMY2B relative to wolves during or after the dog domestication process, we demonstrate that positive selection continued to act on amylase copy number in dog breeds that consumed starch-rich diets in time periods after domestication. Furthermore, we found that introgression with wolves is not responsible for deterioration of positive selection on AMY2B among diverse dog breeds. Together, this supports the hypothesis that the amylase copy number expansion is found universally in dogs.

  8. Sample processing considerations for detecting copy number changes in formalin-fixed, paraffin-embedded tissues.

    Science.gov (United States)

    Jacobs, Sharoni

    2012-11-01

    The Whole Genome Sampling Analysis (WGSA) assay in combination with Affymetrix GeneChip Mapping Arrays is used for copy number analysis of high-quality DNA samples (i.e., samples that have been collected from blood, fresh or frozen tissue, or cell lines). Formalin-fixed, paraffin-embedded (FFPE) samples, however, represent the most prevalent form of archived clinical samples, but they provide additional challenges for molecular assays. FFPE processing usually results in the degradation of FFPE DNA and in the contamination and chemical modification of these DNA samples. Because of these issues, FFPE DNA is not suitable for all molecular assays designed for high-quality DNA samples. Strategies recommended for processing FFPE DNA samples through WGSA and to the Mapping arrays are described here.

  9. Canine Mammary Tumours Are Affected by Frequent Copy Number Aberrations, including Amplification of MYC and Loss of PTEN.

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    Kaja S Borge

    Full Text Available Copy number aberrations frequently occur during the development of many cancers. Such events affect dosage of involved genes and may cause further genomic instability and progression of cancer. In this survey, canine SNP microarrays were used to study 117 canine mammary tumours from 69 dogs.We found a high occurrence of copy number aberrations in canine mammary tumours, losses being more frequent than gains. Increased frequency of aberrations and loss of heterozygosity were positively correlated with increased malignancy in terms of histopathological diagnosis. One of the most highly recurrently amplified regions harbored the MYC gene. PTEN was located to a frequently lost region and also homozygously deleted in five tumours. Thus, deregulation of these genes due to copy number aberrations appears to be an important event in canine mammary tumour development. Other potential contributors to canine mammary tumour pathogenesis are COL9A3, INPP5A, CYP2E1 and RB1. The present study also shows that a more detailed analysis of chromosomal aberrations associated with histopathological parameters may aid in identifying specific genes associated with canine mammary tumour progression.The high frequency of copy number aberrations is a prominent feature of canine mammary tumours as seen in other canine and human cancers. Our findings share several features with corresponding studies in human breast tumours and strengthen the dog as a suitable model organism for this disease.

  10. Micro-Scale Genomic DNA Copy Number Aberrations as Another Means of Mutagenesis in Breast Cancer

    Science.gov (United States)

    Chao, Hann-Hsiang; He, Xiaping; Parker, Joel S.; Zhao, Wei; Perou, Charles M.

    2012-01-01

    Introduction In breast cancer, the basal-like subtype has high levels of genomic instability relative to other breast cancer subtypes with many basal-like-specific regions of aberration. There is evidence that this genomic instability extends to smaller scale genomic aberrations, as shown by a previously described micro-deletion event in the PTEN gene in the Basal-like SUM149 breast cancer cell line. Methods We sought to identify if small regions of genomic DNA copy number changes exist by using a high density, gene-centric Comparative Genomic Hybridizations (CGH) array on cell lines and primary tumors. A custom tiling array for CGH (244,000 probes, 200 bp tiling resolution) was created to identify small regions of genomic change, which was focused on previously identified basal-like-specific, and general cancer genes. Tumor genomic DNA from 94 patients and 2 breast cancer cell lines was labeled and hybridized to these arrays. Aberrations were called using SWITCHdna and the smallest 25% of SWITCHdna-defined genomic segments were called micro-aberrations (micro-aberrations, most of which are undetectable using typical-density genome-wide aCGH arrays. The basal-like subtype exhibited the highest incidence of these events. These micro-aberrations sometimes altered expression of the involved gene. We confirmed the presence of the PTEN micro-amplification in SUM149 and by mRNA-seq showed that this resulted in loss of expression of all exons downstream of this event. Micro-aberrations disproportionately affected the 5′ regions of the affected genes, including the promoter region, and high frequency of micro-aberrations was associated with poor survival. Conclusion Using a high-probe-density, gene-centric aCGH microarray, we present evidence of small-scale genomic aberrations that can contribute to gene inactivation. These events may contribute to tumor formation through mechanisms not detected using conventional DNA copy number analyses. PMID:23284754

  11. Copy number variations in spermatogenic failure patients with chromosomal abnormalities and unexplained azoospermia.

    Science.gov (United States)

    Dong, Y; Pan, Y; Wang, R; Zhang, Z; Xi, Q; Liu, R-Z

    2015-12-07

    Male infertility is mostly caused by spermatogenic failure. Currently, routine genetic analyses of unexplained azoospermia or oligozoospermia are limited to the investigation of Y chromosomal microdeletions and chromosome karyotype analyses. The aim of this study was to find spermatogenic failure genes in patients with chromosomal abnormalities and unexplained azoospermia caused by copy number variations in order to provide a theoretical basis for further research. Spermatogenic failure patients consisting of 13 males with chromosomal abnormalities and 20 with unexplained azoospermia were enrolled. The subjects underwent high-throughput genome-wide sequencing to find copy number variants (CNVs), and the results were analyzed using the Database of Genomic Variants, Online Mendelian Inheritance in Man database, and PubMed. The results showed that 16 CNVs were detected in 11 patients with chromosome abnormalities, and 26 CNVs were found in 16 males with azoospermia. Our data showed CNV-involved loci including: three times on 11p11.12 and 14q11.2 and twice on 6p21.32, 13q11, 15q11.11, 16p12.2, and 21q22.3. Some CNVs may involve changes in genetic structure and function or gene mutations, which may affect gene expression in testicular tissues and lead to spermatogenic failure. The involved genes include EDDM3A, EDDM3B, HLA-DRB1, HLA-DQA1, POTE B, GOLGA8C, DNMT3L, ALF, NPHP1, NRG1, RID2, ADAMTS20, TWF1, COX10, MAK, and DNEL1. By applying high throughput genome-wide sequencing to determine CNVs, we provide a number of candidate genes possibly contributing to spermatogenic failure.

  12. DNA copy number aberrations in breast cancer by array comparative genomic hybridization

    DEFF Research Database (Denmark)

    Li, J.; Wang, K.; Li, S.;

    2009-01-01

    Array comparative genomic hybridization (CGH) has been popularly used for analyzing DNA copy number variations in diseases like cancer. In this study, we investigated 82 sporadic samples from 49 breast cancer patients using 1-Mb resolution bacterial artificial chromosome CGH arrays. A number of h...

  13. 10 CFR 51.66 - Environmental report-number of copies; distribution.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Environmental report-number of copies; distribution. 51.66... Implementing Section 102(2) Environmental Reports-Materials Licenses § 51.66 Environmental report—number of... submit to the Director of Nuclear Material Safety and Safeguards an environmental report or...

  14. Spectrum of EGFR gene copy number changes and KRAS gene mutation status in Korean triple negative breast cancer patients.

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    Yoonjung Kim

    Full Text Available Anti-epidermal growth factor receptor (EGFR therapy has been tried in triple negative breast cancer (TNBC patients without evaluation of molecular and clinical predictors in several randomized clinical studies. Only fewer than 20% of metastatic TNBCs showed response to anti-EGFR therapy. In order to increase the overall response rate, first step would be to classify TNBC into good or poor responders according to oncogenic mutation profiles. This study provides the molecular characteristics of TNBCs including EGFR gene copy number changes and mutation status of EGFR and KRAS gene in Korean TNBC patients. Mutation analysis for EGFR, KRAS, BRAF and TP53 from a total of 105 TNBC tissue samples was performed by direct sequencing, peptide nucleic acid-mediated PCR clamping method and real-time PCR. Copy number changes of EGFR gene were evaluated using multiplex ligation-dependent probe amplification. Out of all 105 TNBCs, 15.2% (16/105 showed EGFR copy number changes. Among them, increased or decreased EGFR copy number was detected in 13 (5 single copy gain, 2 amplification and 4 high-copy number amplification and 3 cases (3 hemizygous deletion, respectively. The mutation frequencies of KRAS, EGFR and TP53 gene were 1.9% (G12V and G12D, 1.0% (exon 19 del and 31.4%, respectively. There was no BRAF V600E mutation found. Future studies are needed to evaluate the clinical outcomes of TNBC patients who undergo anti-EGFR therapy according to the genetic status of EGFR.

  15. BIOFILTER AS A FUNCTIONAL ANNOTATION PIPELINE FOR COMMON AND RARE COPY NUMBER BURDEN.

    Science.gov (United States)

    Kim, Dokyoon; Lucas, Anastasia; Glessner, Joseph; Verma, Shefali S; Bradford, Yuki; Li, Ruowang; Frase, Alex T; Hakonarson, Hakon; Peissig, Peggy; Brilliant, Murray; Ritchie, Marylyn D

    2016-01-01

    Recent studies on copy number variation (CNV) have suggested that an increasing burden of CNVs is associated with susceptibility or resistance to disease. A large number of genes or genomic loci contribute to complex diseases such as autism. Thus, total genomic copy number burden, as an accumulation of copy number change, is a meaningful measure of genomic instability to identify the association between global genetic effects and phenotypes of interest. However, no systematic annotation pipeline has been developed to interpret biological meaning based on the accumulation of copy number change across the genome associated with a phenotype of interest. In this study, we develop a comprehensive and systematic pipeline for annotating copy number variants into genes/genomic regions and subsequently pathways and other gene groups using Biofilter - a bioinformatics tool that aggregates over a dozen publicly available databases of prior biological knowledge. Next we conduct enrichment tests of biologically defined groupings of CNVs including genes, pathways, Gene Ontology, or protein families. We applied the proposed pipeline to a CNV dataset from the Marshfield Clinic Personalized Medicine Research Project (PMRP) in a quantitative trait phenotype derived from the electronic health record - total cholesterol. We identified several significant pathways such as toll-like receptor signaling pathway and hepatitis C pathway, gene ontologies (GOs) of nucleoside triphosphatase activity (NTPase) and response to virus, and protein families such as cell morphogenesis that are associated with the total cholesterol phenotype based on CNV profiles (permutation p-value Biofilter can be used for CNV data from any genotyping or sequencing platform and to explore CNV enrichment for any traits or phenotypes. Biofilter continues to be a powerful bioinformatics tool for annotating, filtering, and constructing biologically informed models for association analysis - now including copy number

  16. Application of BAC-probes to visualize copy number variants (CNVs).

    Science.gov (United States)

    Weise, Anja; Othman, Moneeb A K; Bhatt, Samarth; Löhmer, Sharon; Liehr, Thomas

    2015-01-01

    Copy number variations (CNVs) are structural variations of the human genome. These alterations result in variant copy numbers of certain stretches of DNA. In other words, some regions may be present in more or less copies than in a reference genome; however, these copy number changes do not have any impact on the phenotype. Also, CNVs may be extremely large and cytogenetically detectable or submicroscopic but still spanning several megabasepairs (Mb). In the recent years, array technology has identified especially the latter ones as so-called copy number variant (CNV) polymorphisms. These CNVs are detected in ~12 % of the human genome sequences and may comprise several hundred kilobasepairs. CNVs contribute significantly to the inter-individual differences in humans, and can range between 0.5 and 1.5 Mb amongst different genomes, well within the level of detection using cytogenetics techniques. Thus, they can be visualized by FISH using bacterial artificial chromosomes (BACs) as probes. Here we describe a method that enables discrimination of individual homologous chromosomes at the single cell level based on CNVs in the genome, called parental origin determination fluorescence in situ hybridization (POD-FISH). Possible fields of applications of this single cell-directed approach are in analyses of the parental origin of single chromosomes in inherited and acquired chromosomal aberrations.

  17. Use of competitive PCR to assay copy number of repetitive elements in banana.

    Science.gov (United States)

    Baurens, F C; Noyer, J L; Lanaud, C; Lagoda, P J

    1996-11-27

    Banana is one of the most important subtropical fruit crops. Genetic improvement by traditional breeding strategies is difficult and better knowledge of genomic structure is needed. Repeated sequences are powerful markers for genetic fingerprinting. The method proposed here to determine the copy number of nuclear repetitive elements is based on competitive reverse transcription-polymerase chain reaction and can also be used for quantifying cytosolic sequences. The reliability of this method was investigated on crude preparations of total DNA. Variations due to the heterogeneity of crude DNA extracts showed that a single locus reference is needed for accurate quantification. A mapped microsatellite locus was used to normalize copy number measurements. Copy number assay of repetitive elements using this method clearly distinguishes between the two banana subspecies investigated: Musa acuminata spp. banskii and M. acuminata spp. malaccensis. Two repetitive sequence families, pMaCIR1115 and pA9-26, were assayed that cover up to 1% of the M. acuminata genome. Their copy number varied up to six fold between the two subspecies. Furthermore, sequence quantification showed that mitochondrial genomes are present in crude leaf-extracted banana DNA at up to 40 copies per cell.

  18. EPSPS Gene Copy Number and Whole-Plant Glyphosate Resistance Level in Kochia scoparia.

    Science.gov (United States)

    Gaines, Todd A; Barker, Abigail L; Patterson, Eric L; Westra, Philip; Westra, Eric P; Wilson, Robert G; Jha, Prashant; Kumar, Vipan; Kniss, Andrew R

    2016-01-01

    Glyphosate-resistant (GR) Kochia scoparia has evolved in dryland chemical fallow systems throughout North America and the mechanism of resistance involves 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) gene duplication. Agricultural fields in four states were surveyed for K. scoparia in 2013 and tested for glyphosate-resistance level and EPSPS gene copy number. Glyphosate resistance was confirmed in K. scoparia populations collected from sugarbeet fields in Colorado, Wyoming, and Nebraska, and Montana. Glyphosate resistance was also confirmed in K. scoparia accessions collected from wheat-fallow fields in Montana. All GR samples had increased EPSPS gene copy number, with median population values up to 11 from sugarbeet fields and up to 13 in Montana wheat-fallow fields. The results indicate that glyphosate susceptibility can be accurately diagnosed using EPSPS gene copy number.

  19. CCL3L gene copy number and survival in an HIV-1 infected Zimbabwean population

    DEFF Research Database (Denmark)

    Larsen, Margit Hørup; Thørner, Lise Wegner; Zinyama, Rutendo

    2012-01-01

    The C-C motif chemokine ligand 3-like (CCL3L) protein is a potent chemoattractant which by binding to C-C chemokine receptor type 5 (CCR5) inhibits human immunodeficiency virus (HIV) entry. Copy number variation (CNV) of the CCL3L has been shown to be associated with HIV susceptibility and progre......The C-C motif chemokine ligand 3-like (CCL3L) protein is a potent chemoattractant which by binding to C-C chemokine receptor type 5 (CCR5) inhibits human immunodeficiency virus (HIV) entry. Copy number variation (CNV) of the CCL3L has been shown to be associated with HIV susceptibility.......9), viral load (P=0.9), or CCL3 protein levels (P=1.0). Survival among the HIV infected individuals did not differ according to CCL3L copy number. In this cohort, CCL3L CNV did not affect HIV status, pathogenesis, or survival....

  20. Relative Copy Number Variations of CYP2C19 in South Indian Population

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    Anichavezhi Devendran

    2012-01-01

    Full Text Available CYP2C19 is a polymorphic enzyme involved in the metabolism of clinically important drugs. Genotype-phenotype association studies of CYP2C19 have reported wide ranges in the metabolic ratios of its substrates. These discrepancies could be attributed to the variations in the promoter region and this aspect has been reported recently. The observations in the recent reports on the influence of promoter region variants on the metabolism of CYP2C19 substrates might also have been influenced by the copy number variations of CYP2C19. In this paper, we describe copy number variations of CYP2C19 using real-time polymerase chain reaction by comparative Ct method. No copy number variations were observed in the south Indian population indicating the observed discrepancies in genotype-phenotype association studies might be due to the regulatory region polymorphisms as reported earlier.

  1. Genome-wide copy number profiling to detect gene amplifications in neural progenitor cells

    Directory of Open Access Journals (Sweden)

    U. Fischer

    2014-12-01

    Full Text Available DNA sequence amplification occurs at defined stages during normal development in amphibians and flies and seems to be restricted in humans to drug-resistant and tumor cells only. We used array-CGH to discover copy number changes including gene amplifications and deletions during differentiation of human neural progenitor cells. Here, we describe cell culture features, DNA extraction, and comparative genomic hybridization (CGH analysis tailored towards the identification of genomic copy number changes. Further detailed analysis of amplified chromosome regions associated with this experiment, was published by Fischer and colleagues in PLOS One in 2012 (Fischer et al., 2012. We provide detailed information on deleted chromosome regions during differentiation and give an overview on copy number changes during differentiation induction for two representative chromosome regions.

  2. Gyrase activity and number of copies of the gyrase B subunit gene in Haemophilus influenzae

    Energy Technology Data Exchange (ETDEWEB)

    Cabrera-Juarez, E.; Setlow, J.K.

    1985-11-01

    Gyrase activities in extracts of various strains of Haemophilus influenzae can differ by more than an order of magnitude. Measurements of in vitro activity and copy number indicated that most of these differences arose from variations in the number of copies of the gene for the gyrase B subunit, with some strains containing multicopy plasmids coding for that subunit. The quantitative relationship between gyrase and copy number depended on the mutations in the plasmids and in the host. The possibility that the in vivo gyrase activity did not reflect the in vitro data was explored by measurement of alkaline phosphatase and ATPase activity in the extracts. Alkaline phosphatase activity increased with increasing gyrase activity measured in vitro, but ATPase activity did not. The authors conclude that extra supercoiling enhanced transcription of the alkaline phosphatase gene but not the ATPase gene and that it is unlikely that there is much discrepancy between gyrase activity assayed in vitro and the activity in the cell.

  3. Mitochondrial DNA Copy Number in Peripheral Blood Cells and Risk of Developing Breast Cancer.

    Science.gov (United States)

    Lemnrau, Alina; Brook, Mark N; Fletcher, Olivia; Coulson, Penny; Tomczyk, Katarzyna; Jones, Michael; Ashworth, Alan; Swerdlow, Anthony; Orr, Nick; Garcia-Closas, Montserrat

    2015-07-15

    Increased mitochondrial DNA (mtDNA) copy number in peripheral blood cells (PBC) has been associated with the risk of developing several tumor types. Here we evaluate sources of variation of this biomarker and its association with breast cancer risk in a prospective cohort study. mtDNA copy number was measured using quantitative real-time PCR on PBC DNA samples from participants in the UK-based Breakthrough Generations Study. Temporal and assay variation was evaluated in a serial study of 91 women, with two blood samples collected approximately 6-years apart. Then, associations with breast cancer risk factors and risk were evaluated in 1,108 cases and 1,099 controls using a nested case-control design. In the serial study, mtDNA copy number showed low assay variation but large temporal variation [assay intraclass correlation coefficient (ICC), 79.3%-87.9%; temporal ICC, 38.3%). Higher mtDNA copy number was significantly associated with younger age at blood collection, being premenopausal, having an older age at menopause, and never taking HRT, both in cases and controls. Based on measurements in a single blood sample taken on average 6 years before diagnosis, higher mtDNA copy number was associated with increased breast cancer risk [OR (95% CI) for highest versus lowest quartile, 1.37 (1.02-1.83); P trend = 0.007]. In conclusion, mtDNA copy number is associated with breast cancer risk and represents a promising biomarker for risk assessment. The relatively large temporal variation should be taken into account in future analyses.

  4. Sequenza: allele-specific copy number and mutation profiles from tumor sequencing data.

    Science.gov (United States)

    Favero, F; Joshi, T; Marquard, A M; Birkbak, N J; Krzystanek, M; Li, Q; Szallasi, Z; Eklund, A C

    2015-01-01

    Exome or whole-genome deep sequencing of tumor DNA along with paired normal DNA can potentially provide a detailed picture of the somatic mutations that characterize the tumor. However, analysis of such sequence data can be complicated by the presence of normal cells in the tumor specimen, by intratumor heterogeneity, and by the sheer size of the raw data. In particular, determination of copy number variations from exome sequencing data alone has proven difficult; thus, single nucleotide polymorphism (SNP) arrays have often been used for this task. Recently, algorithms to estimate absolute, but not allele-specific, copy number profiles from tumor sequencing data have been described. We developed Sequenza, a software package that uses paired tumor-normal DNA sequencing data to estimate tumor cellularity and ploidy, and to calculate allele-specific copy number profiles and mutation profiles. We applied Sequenza, as well as two previously published algorithms, to exome sequence data from 30 tumors from The Cancer Genome Atlas. We assessed the performance of these algorithms by comparing their results with those generated using matched SNP arrays and processed by the allele-specific copy number analysis of tumors (ASCAT) algorithm. Comparison between Sequenza/exome and SNP/ASCAT revealed strong correlation in cellularity (Pearson's r = 0.90) and ploidy estimates (r = 0.42, or r = 0.94 after manual inspecting alternative solutions). This performance was noticeably superior to previously published algorithms. In addition, in artificial data simulating normal-tumor admixtures, Sequenza detected the correct ploidy in samples with tumor content as low as 30%. The agreement between Sequenza and SNP array-based copy number profiles suggests that exome sequencing alone is sufficient not only for identifying small scale mutations but also for estimating cellularity and inferring DNA copy number aberrations. © The Author 2014. Published by Oxford University Press on behalf of

  5. Loss of the Association between Telomere Length and Mitochondrial DNA Copy Number Contribute to Colorectal Carcinogenesis.

    Science.gov (United States)

    Lee, Hyunsu; Cho, Ji-Hyoung; Park, Won-Jin; Jung, Soo-Jung; Choi, In-Jang; Lee, Jae-Ho

    2017-05-09

    Positive association between telomere length and mitochondrial DNA (mtDNA) copy number were introduced in healthy and patients with psychiatric disorder. Based on frequent genetic changes of telomere and mitochondria in colorectal carcinomas (CRC), we studied their clinical characteristics and their association in colorectal carcinogenesis. DNA was extracted from 109 CRCs, 64 colorectal tubular adenomas (TAs), and 28 serrated polyps (SPs), and then, telomere length and mtDNA copy number were analyzed in these legions by using a real-time PCR assay. Telomere length and mtDNA copy number (mean ± S.D) in CRCs was 1.87 ± 1.52 and 1.61 ± 1.37, respectively. In TAs and SPs, relative mtDNA copy number was 0.92 ± 0.71 and 1.84 ± 1.06, respectively, shoing statistical difference (p = 0.017). However, telomere length was similar in these precancerous legions. Telomere length and mtDNA copy number did not show clinical and prognostic values in CRCs, however, positive correlation between telomere length and mitochondrial DNA copy number were found in CRC (r = 0.408, p < 0.001). However, this association was not shown in precancerous lesions (r = -0.031, p = 0.765). This result suggests that loss of co-regulation between telomeres and mitochondrial function may induce the initiation or play a role as trigger factor of colorectal carcinogenesis.

  6. Platform comparison of detecting copy number variants with microarrays and whole-exome sequencing

    Directory of Open Access Journals (Sweden)

    Joep de Ligt

    2014-12-01

    Full Text Available Copy number variation (CNV is a common source of genetic variation that has been implicated in many genomic disorders, Mendelian diseases, and common/complex traits. Genomic microarrays are often employed for CNV detection. More recently, whole-exome sequencing (WES has enabled detection of clinically relevant point mutations and small insertion—deletion exome wide. We evaluated (de Ligt et al. 2013 [1] the utility of short-read WES (SOLiD 5500xl to detect clinically relevant CNVs in DNA from 10 patients with intellectual disability and compared these results to data from three independent high-resolution microarray platforms. Calls made by the different platforms and detection software are available at dbVar under nstd84.

  7. Global diversity, population stratification, and selection of human copy number variation

    Science.gov (United States)

    Sudmant, Peter H.; Mallick, Swapan; Nelson, Bradley J.; Hormozdiari, Fereydoun; Krumm, Niklas; Huddleston, John; Coe, Bradley P.; Baker, Carl; Nordenfelt, Susanne; Bamshad, Michael; Jorde, Lynn B.; Posukh, Olga L.; Sahakyan, Hovhannes; Watkins, W. Scott; Yepiskoposyan, Levon; Abdullah, M. Syafiq; Bravi, Claudio M.; Capelli, Cristian; Hervig, Tor; Wee, Joseph T. S.; Tyler-Smith, Chris; van Driem, George; Romero, Irene Gallego; Jha, Aashish R.; Karachanak-Yankova, Sena; Toncheva, Draga; Comas, David; Henn, Brenna; Kivisild, Toomas; Ruiz-Linares, Andres; Sajantila, Antti; Metspalu, Ene; Parik, Jüri; Villems, Richard; Starikovskaya, Elena B.; Ayodo, George; Beall, Cynthia M.; Di Rienzo, Anna; Hammer, Michael; Khusainova, Rita; Khusnutdinova, Elza; Klitz, William; Winkler, Cheryl; Labuda, Damian; Metspalu, Mait; Tishkoff, Sarah A.; Dryomov, Stanislav; Sukernik, Rem; Patterson, Nick; Reich, David; Eichler, Evan E.

    2015-01-01

    In order to explore the diversity and selective signatures of duplication and deletion human copy number variants (CNVs), we sequenced 236 individuals from 125 distinct human populations. We observed that duplications exhibit fundamentally different population genetic and selective signatures than deletions and are more likely to be stratified between human populations. Through reconstruction of the ancestral human genome, we identify megabases of DNA lost in different human lineages and pinpoint large duplications that introgressed from the extinct Denisova lineage now found at high frequency exclusively in Oceanic populations. We find that the proportion of CNV base pairs to single nucleotide variant base pairs is greater among non-Africans than it is among African populations, but we conclude that this difference is likely due to unique aspects of non-African population history as opposed to differences in CNV load. PMID:26249230

  8. Low copy number DNA profiling from isolated sperm using the aureka®-micromanipulation system.

    Science.gov (United States)

    Schneider, C; Müller, U; Kilper, R; Siebertz, B

    2012-07-01

    A new cell isolation technique linked to the aureka® micromanipulation system (aureka®) was used to pick sperm from mixed samples containing sperm and epithelial cells. Both cell types were stained using the HY-LITER™ high-resolution, fluorescent staining kit. To isolate a single sperm of interest under a fluorescent microscope, a specific microsphere picking technique was used. This sensitive and reliable cell identification and isolation technique enables low-copy-number (LCN) DNA profiling, as few as 20 sperm are sufficient for obtaining a full short tandem repeat (STR) profile without any allelic drop out. The presented protocol covers the whole workflow, from sample staining and cell pick up to STR analysis.

  9. Topoisomerase I copy number alterations as biomarker for irinotecan efficacy in metastatic colorectal cancer

    DEFF Research Database (Denmark)

    Palshof, Jesper Andreas; Høgdall, Estrid Vilma Solyom; Poulsen, Tim Svenstrup

    2017-01-01

    Background No biomarker exists to guide the optimal choice of chemotherapy for patients with metastatic colorectal cancer. We examined the copy numbers (CN) of topoisomerase I (TOP1) as well as the ratios of TOP1/CEN-20 and TOP1/CEN-2 as biomarkers for irinotecan efficacy in patients with metasta......Background No biomarker exists to guide the optimal choice of chemotherapy for patients with metastatic colorectal cancer. We examined the copy numbers (CN) of topoisomerase I (TOP1) as well as the ratios of TOP1/CEN-20 and TOP1/CEN-2 as biomarkers for irinotecan efficacy in patients...

  10. Copy Number Variation Analysis by Array Analysis of Single Cells Following Whole Genome Amplification.

    Science.gov (United States)

    Dimitriadou, Eftychia; Zamani Esteki, Masoud; Vermeesch, Joris Robert

    2015-01-01

    Whole genome amplification is required to ensure the availability of sufficient material for copy number variation analysis of a genome deriving from an individual cell. Here, we describe the protocols we use for copy number variation analysis of non-fixed single cells by array-based approaches following single-cell isolation and whole genome amplification. We are focusing on two alternative protocols, an isothermal and a PCR-based whole genome amplification method, followed by either comparative genome hybridization (aCGH) or SNP array analysis, respectively.

  11. Importance of rare gene copy number alterations for personalized tumor characterization and survival analysis.

    Science.gov (United States)

    Seifert, Michael; Friedrich, Betty; Beyer, Andreas

    2016-10-03

    It has proven exceedingly difficult to ascertain rare copy number alterations (CNAs) that may have strong effects in individual tumors. We show that a regulatory network inferred from gene expression and gene copy number data of 768 human cancer cell lines can be used to quantify the impact of patient-specific CNAs on survival signature genes. A focused analysis of tumors from six tissues reveals that rare patient-specific gene CNAs often have stronger effects on signature genes than frequent gene CNAs. Further comparison to a related network-based approach shows that the integration of indirectly acting gene CNAs significantly improves the survival analysis.

  12. SMN1 and SMN2 copy numbers in cell lines derived from patients with spinal muscular atrophy as measured by array digital PCR.

    Science.gov (United States)

    Stabley, Deborah L; Harris, Ashlee W; Holbrook, Jennifer; Chubbs, Nicholas J; Lozo, Kevin W; Crawford, Thomas O; Swoboda, Kathryn J; Funanage, Vicky L; Wang, Wenlan; Mackenzie, William; Scavina, Mena; Sol-Church, Katia; Butchbach, Matthew E R

    2015-07-01

    Proximal spinal muscular atrophy (SMA) is an early-onset motor neuron disease characterized by loss of α-motor neurons and associated muscle atrophy. SMA is caused by deletion or other disabling mutation of survival motor neuron 1 (SMN1). In the human genome, a large duplication of the SMN-containing region gives rise to a second copy of this gene (SMN2) that is distinguishable by a single nucleotide change in exon 7. Within the SMA population, there is substantial variation in SMN2 copy number; in general, those individuals with SMA who have a high SMN2 copy number have a milder disease. Because SMN2 functions as a disease modifier, its accurate copy number determination may have clinical relevance. In this study, we describe the development of an assay to assess SMN1 and SMN2 copy numbers in DNA samples using an array-based digital PCR (dPCR) system. This dPCR assay can accurately and reliably measure the number of SMN1 and SMN2 copies in DNA samples. In a cohort of SMA patient-derived cell lines, the assay confirmed a strong inverse correlation between SMN2 copy number and disease severity. Array dPCR is a practical technique to determine, accurately and reliably, SMN1 and SMN2 copy numbers from SMA samples.

  13. Extensive genome heterogeneity leads to preferential allele expression and copy number-dependent expression in cultivated potato.

    Science.gov (United States)

    Pham, Gina M; Newton, Linsey; Wiegert-Rininger, Krystle; Vaillancourt, Brieanne; Douches, David S; Buell, C Robin

    2017-09-04

    Relative to homozygous diploids, the presence of multiple homologs or homeologs in polyploids affords greater tolerance to mutations that can impact genome evolution. In this study, we describe sequence and structural variation in the genomes of six accessions of cultivated potato (Solanum tuberosum L.), a vegetatively propagated autotetraploid, and their impact on the transcriptome. Sequence diversity was high with a mean SNP rate of approximately 1 per 50 bases suggestive of high levels of allelic diversity. Additive gene expression was observed in leaves (3,605 genes) and tubers (6,156 genes) that contrasted the preferential allele expression of between 2,180 and 3,502 and 3,367 and 5,270 genes in the leaf and tuber transcriptome, respectively. Preferential allele expression was significantly associated with evolutionarily conserved genes suggesting selection of specific alleles of genes responsible for biological processes common to angiosperms during the breeding selection process. Copy number variation was rampant with between 16,098 and 18,921 genes in each cultivar exhibiting duplication or deletion. Copy number variable genes tended to be evolutionarily recent, lowly expressed, and enriched in genes that show increased expression in response to biotic and abiotic stress treatments suggestive of a role in adaptation. Gene copy number impacts on gene expression were detected with 528 genes having correlations between copy number and gene expression. Collectively, these data suggest that in addition to allelic variation of coding sequence, the heterogenous nature of the tetraploid potato genome contributes to a highly dynamic transcriptome impacted by allele preferential and copy number-dependent expression effects. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  14. Rare de novo copy number variants in patients with congenital pulmonary atresia.

    Directory of Open Access Journals (Sweden)

    Li Xie

    Full Text Available BACKGROUND: Ongoing studies using genomic microarrays and next-generation sequencing have demonstrated that the genetic contributions to cardiovascular diseases have been significantly ignored in the past. The aim of this study was to identify rare copy number variants in individuals with congenital pulmonary atresia (PA. METHODS AND RESULTS: Based on the hypothesis that rare structural variants encompassing key genes play an important role in heart development in PA patients, we performed high-resolution genome-wide microarrays for copy number variations (CNVs in 82 PA patient-parent trios and 189 controls with an Illumina SNP array platform. CNVs were identified in 17/82 patients (20.7%, and eight of these CNVs (9.8% are considered potentially pathogenic. Five de novo CNVs occurred at two known congenital heart disease (CHD loci (16p13.1 and 22q11.2. Two de novo CNVs that may affect folate and vitamin B12 metabolism were identified for the first time. A de novo 1-Mb deletion at 17p13.2 may represent a rare genomic disorder that involves mild intellectual disability and associated facial features. CONCLUSIONS: Rare CNVs contribute to the pathogenesis of PA (9.8%, suggesting that the causes of PA are heterogeneous and pleiotropic. Together with previous data from animal models, our results might help identify a link between CHD and folate-mediated one-carbon metabolism (FOCM. With the accumulation of high-resolution SNP array data, these previously undescribed rare CNVs may help reveal critical gene(s in CHD and may provide novel insights about CHD pathogenesis.

  15. Pfmdr1 copy number and arteminisin derivatives combination therapy failure in falciparum malaria in Cambodia

    Directory of Open Access Journals (Sweden)

    Wongsrichanalai Chansuda

    2009-01-01

    Full Text Available Abstract Background The combination of artesunate and mefloquine was introduced as the national first-line treatment for Plasmodium falciparum malaria in Cambodia in 2000. However, recent clinical trials performed at the Thai-Cambodian border have pointed to the declining efficacy of both artesunate-mefloquine and artemether-lumefantrine. Since pfmdr1 modulates susceptibility to mefloquine and artemisinin derivatives, the aim of this study was to assess the link between pfmdr1 copy number, in vitro susceptibility to individual drugs and treatment failure to combination therapy. Methods Blood samples were collected from P. falciparum-infected patients enrolled in two in vivo efficacy studies in north-western Cambodia: 135 patients were treated with artemether-lumefantrine (AL group in Sampovloun in 2002 and 2003, and 140 patients with artesunate-mefloquine (AM group in Sampovloun and Veal Veng in 2003 and 2004. At enrollment, the in vitro IC50 was tested and the strains were genotyped for pfmdr1 copy number by real-time PCR. Results The pfmdr1 copy number was analysed for 115 isolates in the AM group, and for 109 isolates in the AL group. Parasites with increased pfmdr1 copy number had significantly reduced in vitro susceptibility to mefloquine, lumefantrine and artesunate. There was no association between pfmdr1 polymorphisms and in vitro susceptibilities. In the patients treated with AM, the mean pfmdr1copy number was lower in subjects with adequate clinical and parasitological response compared to those who experienced late treatment failure (n = 112, p p = 0.364. The presence of three or more copies of pfmdr1 were associated with recrudescence in artesunate-mefloquine treated patients (hazard ratio (HR = 7.80 [95%CI: 2.09–29.10], N = 115, p = 0.002 but not with recrudescence in artemether-lumefantrine treated patients (HR = 1.03 [95%CI: 0.24–4.44], N = 109, p = 0.969. Conclusion This study shows that pfmdr1 copy number is a molecular

  16. Inducible amplification of gene copy number and heterologous protein production in the yeast Kluyveromyces lactis.

    Science.gov (United States)

    Morlino, G B; Tizzani, L; Fleer, R; Frontali, L; Bianchi, M M

    1999-11-01

    Heterologous protein production can be doubled by increasing the copy number of the corresponding heterologous gene. We constructed a host-vector system in the yeast Kluyveromyces lactis that was able to induce copy number amplification of pKD1 plasmid-based vectors upon expression of an integrated copy of the plasmid recombinase gene. We increased the production and secretion of two heterologous proteins, glucoamylase from the yeast Arxula adeninivorans and mammalian interleukin-1beta, following gene dosage amplification when the heterologous genes were carried by pKD1-based vectors. The choice of the promoters for expression of the integrated recombinase gene and of the episomal heterologous genes are critical for the mitotic stability of the host-vector system.

  17. Effect of Promoters and Plasmid Copy Number on Cyt1A Synthesis and Crystal Assembly in Bacillus thuringiensis.

    Science.gov (United States)

    Park, Hyun-Woo; Hice, Robert H; Federici, Brian A

    2016-01-01

    Cyt1Aa is a major mosquitocidal protein synthesized during sporulation of Bacillus thuringiensis subsp. israelensis, composing more than 50% of its parasporal body. This high level of synthesis is due to several factors including three strong sporulation-dependent promoters, a strong transcription termination sequence, and an associated 20-kDa helper protein. Cyt1Aa's toxicity is low compared to the Cry proteins of this species, namely, Cry4Aa, Cry4Ba, and Cry11Aa, but it nevertheless plays an important role in the biology of B. thuringiensis subsp. israelensis in that it synergizes their mosquitocidal toxicity and suppresses the evolution of resistance. In the present study, the effects of using different cyt1Aa promoter combinations and plasmid copy number on synthesis of Cyt1Aa were evaluated. Using the 4Q7 (plasmid-cured) strain of B. thuringiensis subsp. israelensis as an experimental host, a plasmid copy number of two or three yielded no Cyt1Aa, whereas a copy number of four yielded only small crystals, even when expression was driven by one of the wild-type promoters. However, using all three wild-type promoters and a plasmid copy number of 20 yielded Cyt1A crystals tenfold larger than those produced by one promoter and a plasmid copy number of four. High levels of Cyt1Aa synthesis resulted in significantly fewer spores per unit medium and imperfectly formed crystals. Similar results were obtained when Cyt1Aa synthesis was evaluated using the same expression constructs in a mutant strain of B. thuringiensis subsp. israelensis that lacks the cyt1Aa gene.

  18. Accurate measurement of transgene copy number in crop plants using droplet digital PCR.

    Science.gov (United States)

    Collier, Ray; Dasgupta, Kasturi; Xing, Yan-Ping; Hernandez, Bryan Tarape; Shao, Min; Rohozinski, Dominica; Kovak, Emma; Lin, Jeanie; de Oliveira, Maria Luiza P; Stover, Ed; McCue, Kent F; Harmon, Frank G; Blechl, Ann; Thomson, James G; Thilmony, Roger

    2017-06-01

    Genetic transformation is a powerful means for the improvement of crop plants, but requires labor- and resource-intensive methods. An efficient method for identifying single-copy transgene insertion events from a population of independent transgenic lines is desirable. Currently, transgene copy number is estimated by either Southern blot hybridization analyses or quantitative polymerase chain reaction (qPCR) experiments. Southern hybridization is a convincing and reliable method, but it also is expensive, time-consuming and often requires a large amount of genomic DNA and radioactively labeled probes. Alternatively, qPCR requires less DNA and is potentially simpler to perform, but its results can lack the accuracy and precision needed to confidently distinguish between one- and two-copy events in transgenic plants with large genomes. To address this need, we developed a droplet digital PCR-based method for transgene copy number measurement in an array of crops: rice, citrus, potato, maize, tomato and wheat. The method utilizes specific primers to amplify target transgenes, and endogenous reference genes in a single duplexed reaction containing thousands of droplets. Endpoint amplicon production in the droplets is detected and quantified using sequence-specific fluorescently labeled probes. The results demonstrate that this approach can generate confident copy number measurements in independent transgenic lines in these crop species. This method and the compendium of probes and primers will be a useful resource for the plant research community, enabling the simple and accurate determination of transgene copy number in these six important crop species. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

  19. Genome-wide copy number variation analysis in a Chinese autism spectrum disorder cohort

    Science.gov (United States)

    Guo, Hui; Peng, Yu; Hu, Zhengmao; Li, Ying; Xun, Guanglei; Ou, Jianjun; Sun, Liangdan; Xiong, Zhimin; Liu, Yanling; Wang, Tianyun; Chen, Jingjing; Xia, Lu; Bai, Ting; Shen, Yidong; Tian, Qi; Hu, Yiqiao; Shen, Lu; Zhao, Rongjuan; Zhang, Xuejun; Zhang, Fengyu; Zhao, Jingping; Zou, Xiaobing; Xia, Kun

    2017-01-01

    Autism spectrum disorder (ASD) describes a group of neurodevelopmental disorders with high heritability, although the underlying genetic determinants of ASDs remain largely unknown. Large-scale whole-genome studies of copy number variation in Han Chinese samples are still lacking. We performed a genome-wide copy number variation analysis of 343 ASD trios, 203 patients with sporadic cases and 988 controls in a Chinese population using Illumina genotyping platforms to identify CNVs and related genes that may contribute to ASD risk. We identified 32 rare CNVs larger than 1 Mb in 31 patients. ASD patients were found to carry a higher global burden of rare, large CNVs than controls. Recurrent de novo or case-private CNVs were found at 15q11-13, Xp22.3, 15q13.1–13.2, 3p26.3 and 2p12. The de novo 15q11–13 duplication was more prevalent in this Chinese population than in those with European ancestry. Several genes, including GRAMD2 and STAM, were implicated as novel ASD risk genes when integrating whole-genome CNVs and whole-exome sequencing data. We also identified several CNVs that include known ASD genes (SHANK3, CDH10, CSMD1) or genes involved in nervous system development (NYAP2, ST6GAL2, GRM6). Besides, our study also implicated Contactins-NYAPs-WAVE1 pathway in ASD pathogenesis. Our findings identify ASD-related CNVs in a Chinese population and implicate novel ASD risk genes and related pathway for further study. PMID:28281572

  20. Diversity and population-genetic properties of copy number variations and multicopy genes in cattle.

    Science.gov (United States)

    Bickhart, Derek M; Xu, Lingyang; Hutchison, Jana L; Cole, John B; Null, Daniel J; Schroeder, Steven G; Song, Jiuzhou; Garcia, Jose Fernando; Sonstegard, Tad S; Van Tassell, Curtis P; Schnabel, Robert D; Taylor, Jeremy F; Lewin, Harris A; Liu, George E

    2016-06-01

    The diversity and population genetics of copy number variation (CNV) in domesticated animals are not well understood. In this study, we analysed 75 genomes of major taurine and indicine cattle breeds (including Angus, Brahman, Gir, Holstein, Jersey, Limousin, Nelore, and Romagnola), sequenced to 11-fold coverage to identify 1,853 non-redundant CNV regions. Supported by high validation rates in array comparative genomic hybridization (CGH) and qPCR experiments, these CNV regions accounted for 3.1% (87.5 Mb) of the cattle reference genome, representing a significant increase over previous estimates of the area of the genome that is copy number variable (∼2%). Further population genetics and evolutionary genomics analyses based on these CNVs revealed the population structures of the cattle taurine and indicine breeds and uncovered potential diversely selected CNVs near important functional genes, including AOX1, ASZ1, GAT, GLYAT, and KRTAP9-1 Additionally, 121 CNV gene regions were found to be either breed specific or differentially variable across breeds, such as RICTOR in dairy breeds and PNPLA3 in beef breeds. In contrast, clusters of the PRP and PAG genes were found to be duplicated in all sequenced animals, suggesting that subfunctionalization, neofunctionalization, or overdominance play roles in diversifying those fertility-related genes. These CNV results provide a new glimpse into the diverse selection histories of cattle breeds and a basis for correlating structural variation with complex traits in the future. Published by Oxford University Press on behalf of Kazusa DNA Research Institute 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  1. Mitochondrial DNA copy number is regulated by DNA methylation and demethylation of POLGA in stem and cancer cells and their differentiated progeny.

    Science.gov (United States)

    Lee, W; Johnson, J; Gough, D J; Donoghue, J; Cagnone, G L M; Vaghjiani, V; Brown, K A; Johns, T G; St John, J C

    2015-02-26

    Mitochondrial DNA (mtDNA) copy number is strictly regulated during differentiation so that cells with a high requirement for ATP generated through oxidative phosphorylation have high mtDNA copy number, whereas those with a low requirement have few copies. Using immunoprecipitation of DNA methylation on 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC), which distinguish between de novo DNA methylation and demethylation, respectively, we set out to determine whether DNA methylation at exon 2 of the human mtDNA-specific polymerase (DNA polymerase gamma A (POLGA)) regulates cell-specific mtDNA copy number in highly proliferative and terminally differentiated cells. Highly proliferative cancer and pluripotent and multipotent cells possessed low mtDNA copy number and were highly methylated at exon 2 of POLGA in contrast to post-mitotic cells. Unlike neural stem cells, cancer cells were unable to differentiate and remained extensively DNA methylated at exon 2 of POLGA. However, mtDNA depletion of cancer cells reduced DNA methylation at exon 2 of POLGA as they replenished mtDNA to form tumours in mice. Glioblastoma cells treated with the DNA demethylation agent 5-azacytidine over 28 days of astrocyte-induced differentiation demethylated exon 2 of POLGA leading to increased mtDNA copy number and expression of the astrocyte endpoint marker glial fibrillary acidic protein (GFAP). However, the demethylation agent vitamin C (VitC) was unable to sustain increased mtDNA copy number and differentiation, as was the case when VitC was withdrawn after short-term treatment. These data demonstrate that DNA demethylation of POLGA is an essential regulator of mtDNA copy number and cellular fate and that cancer cells are only able to modulate DNA methylation of POLGA and mtDNA copy number in the presence of a DNA demethylation agent that inhibits de novo methyltransferase 1 activity.

  2. Epidermal growth factor receptor and AKT1 gene copy numbers by multi-gene fluorescence in situ hybridization impact on prognosis in breast cancer.

    Science.gov (United States)

    Li, Jiao; Su, Wei; Zhang, Sheng; Hu, Yunhui; Liu, Jingjing; Zhang, Xiaobei; Bai, Jingchao; Yuan, Weiping; Hu, Linping; Cheng, Tao; Zetterberg, Anders; Lei, Zhenmin; Zhang, Jin

    2015-05-01

    The epidermal growth factor receptor (EGFR)/PI3K/AKT signaling pathway aberrations play significant roles in breast cancer occurrence and development. However, the status of EGFR and AKT1 gene copy numbers remains unclear. In this study, we showed that the rates of EGFR and AKT1 gene copy number alterations were associated with the prognosis of breast cancer. Among 205 patients, high EGFR and AKT1 gene copy numbers were observed in 34.6% and 27.8% of cases by multi-gene fluorescence in situ hybridization, respectively. Co-heightened EGFR/AKT1 gene copy numbers were identified in 11.7% cases. No changes were found in 49.3% of patients. Although changes in EGFR and AKT1 gene copy numbers had no correlation with patients' age, tumor stage, histological grade and the expression status of other molecular makers, high EGFR (P = 0.0002) but not AKT1 (P = 0.1177) gene copy numbers correlated with poor 5-year overall survival. The patients with co-heightened EGFR/AKT1 gene copy numbers displayed a poorer prognosis than those with tumors with only high EGFR gene copy numbers (P = 0.0383). Both Univariate (U) and COX multivariate (C) analyses revealed that high EGFR and AKT1 gene copy numbers (P = 0.000 [U], P = 0.0001 [C]), similar to histological grade (P = 0.001 [U], P = 0.012 [C]) and lymph node metastasis (P = 0.046 [U], P = 0.158 [C]), were independent prognostic indicators of 5-year overall survival. These results indicate that high EGFR and AKT1 gene copy numbers were relatively frequent in breast cancer. Co-heightened EGFR/AKT1 gene copy numbers had a worse outcome than those with only high EGFR gene copy numbers, suggesting that evaluation of these two genes together may be useful for selecting patients for anti-EGFR-targeted therapy or anti-EGFR/AKT1-targeted therapy and for predicting outcomes. © 2015 The Authors. Cancer Science published by Wiley Publishing Asia Pty Ltd on behalf of Japanese Cancer Association.

  3. Whole-genome sequencing reveals the diversity of cattle copy number variations and multicopy genes

    Science.gov (United States)

    Structural and functional impacts of copy number variations (CNVs) on livestock genomes are not yet well understood. We identified 1853 CNV regions using population-scale sequencing data generated from 75 cattle representing 8 breeds (Angus, Brahman, Gir, Holstein, Jersey, Limousin, Nelore, Romagnol...

  4. Diversity and population-genetic properties of copy number variations and multicopy genes in cattle

    Science.gov (United States)

    The diversity and population-genetics of copy number variation (CNV) in domesticated animals are not well understood. In this study, we analyzed 75 genomes of major taurine and indicine cattle breeds (including Angus, Brahman, Gir, Holstein, Jersey, Limousin, Nelore, Romagnola), sequenced to 11-fold...

  5. Copy number variations of chromosome 16p13.1 region associated with schizophrenia

    NARCIS (Netherlands)

    Ingason, A.; Rujescu, D.; Cichon, S.; Sigurdsson, E.; Sigmundsson, T.; Pietilainen, O.P.H.; Buizer-Voskamp, J.E.; Strengman, E.; Francks, C.; Muglia, P.; Gylfason, A.; Gustafsson, O.; Olason, P.I.; Steinberg, S.; Hansen, T.; Jakobsen, K.D.; Rasmussen, H.B.; Giegling, I.; Moller, H.J.; Hartmann, A.; Crombie, C.; Fraser, G.; Walker, N.; Lonnqvist, J.; Suvisaari, J.; Tuulio-Henriksson, A.; Bramon, E.; Kiemeney, L.A.L.M.; Franke, B.; Murray, R.; Vassos, E.; Toulopoulou, T.; Muhleisen, T.W.; Tosato, S.; Ruggeri, M.; Djurovic, S.; Andreassen, O.A.; Zhang, Z.; Werge, T.; Ophoff, R.A.; Rietschel, M.; Nothen, M.M.; Petursson, H.; Stefansson, H.; Peltonen, L.; Collier, D.; Stefansson, K.; St Clair, D.M.

    2011-01-01

    Deletions and reciprocal duplications of the chromosome 16p13.1 region have recently been reported in several cases of autism and mental retardation (MR). As genomic copy number variants found in these two disorders may also associate with schizophrenia, we examined 4345 schizophrenia patients and 3

  6. Genome-Wide Analysis Shows Increased Frequency of Copy Number Variation Deletions in Dutch Schizophrenia Patients

    NARCIS (Netherlands)

    Buizer-Voskamp, Jacobine E.; Muntjewerff, Jan-Willem; Strengman, Eric; Sabatti, Chiara; Stefansson, Hreinn; Vorstman, Jacob A. S.; Ophoff, Roel A.; GROUP investigators, [No Value

    2011-01-01

    Background: Since 2008, multiple studies have reported on copy number variations (CNVs) in schizophrenia. However, many regions are unique events with minimal overlap between studies. This makes it difficult to gain a comprehensive overview of all CNVs involved in the etiology of schizophrenia. We p

  7. Alpha-defensin DEFA1A3 gene copy number elevation in Danish Crohn's disease patients

    DEFF Research Database (Denmark)

    Jespersgaard, Cathrine; Fode, Peder; Dybdahl, Marianne

    2011-01-01

    BACKGROUND AND PURPOSE OF STUDY: Extensive copy number variation is observed for the DEFA1A3 gene encoding alpha-defensins 1-3. The objective of this study was to determine the involvement of alpha-defensins in colonic tissue from Crohn's disease (CD) patients and the possible genetic association...

  8. Social Responsiveness Scale-aided analysis of the clinical impact of copy number variations in autism.

    NARCIS (Netherlands)

    Daalen, E. van; Kemner, C.; Verbeek, N.E.; Zwaag, B. van der; Dijkhuizen, T.; Rump, P.; Houben, R.; Slot, R. van 't; Jonge, M.V. de; Staal, W.G.; Beemer, F.A.; Vorstman, J.A.; Burbach, J.P.H.; Amstel, H.K. van; Hochstenbach, R.; Brilstra, E.H.; Poot, M.

    2011-01-01

    Recent array-based studies have detected a wealth of copy number variations (CNVs) in patients with autism spectrum disorders (ASD). Since CNVs also occur in healthy individuals, their contributions to the patient's phenotype remain largely unclear. In a cohort of children with symptoms of ASD, diag

  9. Reduction in mitochondrial DNA copy number in peripheral leukocytes after onset of Huntington's disease

    DEFF Research Database (Denmark)

    Petersen, Maria Hvidberg; Budtz-Jørgensen, Esben; Sørensen, Sven Asger;

    2014-01-01

    to the investigation of the mitochondrial DNA (mtDNA) copy number relative to nuclear DNA (nDNA) in leukocytes from carriers of the HD mutation compared to healthy individuals. We found significantly reduced mtDNA/nDNA in HD mutation carriers compared to controls. A longitudinal study of archive DNA sample pairs from...

  10. Copy number variation in obsessive-compulsive disorder and tourette syndrome: A cross-disorder study

    NARCIS (Netherlands)

    L.M. McGrath; D. Yu (D.); C.R. Marshall (Christian); L.K. Davis (Lea); B. Thiruvahindrapuram (Bhooma); B. Li (Bingbin); C. Cappi (Carolina); G. Gerber (Gloria); A. de Wolf (Anneke); F.A. Schroeder (Frederick); L. Osiecki (Lisa); C. O'Dushlaine (Colm); A. Kirby (Andrew); C. Illmann (Cornelia); S. Haddad (Stephen); P. Gallagher (Patience); J. Fagerness (Jesen); C.L. Barr; L. Bellodi (Laura); F. Benarroch (Fortu); O.J. Bienvenu (Oscar); D.W. Black (Donald W); J. Bloch (Jocelyne); R.D. Bruun (Ruth); C.L. Budman (Cathy); B. Camarena (Beatriz); D. Cath (Daniëlle); M.C. Cavallini (Maria); S. Chouinard; V. Coric (Vladimir); C. Cullen; R. Delorme (Richard); D.A.J.P. Denys (Damiaan); E.M. Derks (Eske); Y. Dion (Yves); M.C. Rosário (Maria); C.E. Eapen (Chundamannil Eapen); P. Evans; P. Falkai (Peter); T.V. Fernandez (Thomas); H. Garrido (Helena); D. Geller (Daniel); H.J. Grabe (Hans Jörgen); M. Grados (Marco); B.D. Greenberg (Benjamin); V. Gross-Tsur (Varda); E. Grünblatt (Edna); M.L. Heiman (Mark); S.M.J. Hemmings (Sian); L.D. Herrera (Luis); A.G. Hounie (Ana); J. Jankovic (Joseph); J.L. Kennedy; R.A. King; R. Kurlan; N. Lanzagorta (Nuria); M. Leboyer (Marion); J.F. Leckman; L. Lennertz (Leonhard); C. Lochner (Christine); T.L. Lowe (Thomas); H.N. Lyon (Helen); F. MacCiardi (Fabio); W. Maier (Wolfgang); J.T. McCracken (James); W.M. McMahon (William); D.L. Murphy (Dennis); A.L. Naarden (Allan); E. Nurmi (Erika); A.J. Pakstis; C. Pato (Carlos); C. Pato (Carlos); J. Piacentini (John); C. Pittenger (Christopher); M.N. Pollak (Michael); V.I. Reus (Victor); M.A. Richter (Margaret); M. Riddle (Mark); M.M. Robertson; D. Rosenberg (David); G.A. Rouleau; S. Ruhrmann (Stephan); A.S. Sampaio (Aline); J. Samuels (Jonathan); P. Sandor (Paul); B. Sheppard (Brooke); H.S. Singer (Harvey); J.H. Smit (Jan); D.J. Stein (Dan); J.A. Tischfield (Jay); H. Vallada (Homero); J. Veenstra-Vanderweele (Jeremy); S. Walitza (Susanne); Y. Wang (Ying); A. Wendland (Annika); Y.Y. Shugart; E.C. Miguel (Euripedes); H. Nicolini (Humberto); B.A. Oostra (Ben); R. Moessner (Rainald); M. Wagner (Michael); A. Ruiz-Linares (Andres); P. Heutink (Peter); G. Nestadt (Gerald); N.B. Freimer (Nelson); T.L. Petryshen (Tracey); D. Posthuma (Danielle); M.A. Jenike (Michael); N.J. Cox (Nancy); G.L. Hanna (Gregory); H. Brentani (Helena); S.W. Scherer (Stephen); P.D. Arnold (Paul); S.E. Stewart; C. Mathews; J.A. Knowles (James A); E.H. Cook (Edwin); D.L. Pauls (David); K. Wang (Kai); J.M. Scharf; B.M. Neale (Benjamin)

    2014-01-01

    textabstractObjective Obsessive-compulsive disorder (OCD) and Tourette syndrome (TS) are heritable neurodevelopmental disorders with a partially shared genetic etiology. This study represents the first genome-wide investigation of large (>500 kb), rare (<1%) copy number variants (CNVs) in OCD and th

  11. Identification of copy number variants defining genomic differences among major human groups.

    Directory of Open Access Journals (Sweden)

    Lluís Armengol

    Full Text Available BACKGROUND: Understanding the genetic contribution to phenotype variation of human groups is necessary to elucidate differences in disease predisposition and response to pharmaceutical treatments in different human populations. METHODOLOGY/PRINCIPAL FINDINGS: We have investigated the genome-wide profile of structural variation on pooled samples from the three populations studied in the HapMap project by comparative genome hybridization (CGH in different array platforms. We have identified and experimentally validated 33 genomic loci that show significant copy number differences from one population to the other. Interestingly, we found an enrichment of genes related to environment adaptation (immune response, lipid metabolism and extracellular space within these regions and the study of expression data revealed that more than half of the copy number variants (CNVs translate into gene-expression differences among populations, suggesting that they could have functional consequences. In addition, the identification of single nucleotide polymorphisms (SNPs that are in linkage disequilibrium with the copy number alleles allowed us to detect evidences of population differentiation and recent selection at the nucleotide variation level. CONCLUSIONS: Overall, our results provide a comprehensive view of relevant copy number changes that might play a role in phenotypic differences among major human populations, and generate a list of interesting candidates for future studies.

  12. Investigation of Copy Number Variation in Children with Conotruncal Heart Defects

    Directory of Open Access Journals (Sweden)

    Carla Marques Rondon Campos

    2015-01-01

    Full Text Available Background: Congenital heart defects (CHD are the most prevalent group of structural abnormalities at birth and one of the main causes of infant morbidity and mortality. Studies have shown a contribution of the copy number variation in the genesis of cardiac malformations. Objectives: Investigate gene copy number variation (CNV in children with conotruncal heart defect. Methods: Multiplex ligation-dependent probe amplification (MLPA was performed in 39 patients with conotruncal heart defect. Clinical and laboratory assessments were conducted in all patients. The parents of the probands who presented abnormal findings were also investigated. Results: Gene copy number variation was detected in 7/39 patients: 22q11.2 deletion, 22q11.2 duplication, 15q11.2 duplication, 20p12.2 duplication, 19p deletion, 15q and 8p23.2 duplication with 10p12.31 duplication. The clinical characteristics were consistent with those reported in the literature associated with the encountered microdeletion/microduplication. None of these changes was inherited from the parents. Conclusions: Our results demonstrate that the technique of MLPA is useful in the investigation of microdeletions and microduplications in conotruncal congenital heart defects. Early diagnosis of the copy number variation in patients with congenital heart defect assists in the prevention of morbidity and decreased mortality in these patients.

  13. Investigation of Copy Number Variation in Children with Conotruncal Heart Defects

    Energy Technology Data Exchange (ETDEWEB)

    Campos, Carla Marques Rondon, E-mail: carlamcampos@uol.com.br [Universidade Federal de Mato Grosso, Cuiabá, MT (Brazil); Zanardo, Evelin Aline; Dutra, Roberta Lelis [Departamento de Patologia - Laboratório de Citogenômica - LIM 03 - Universidade de São Paulo, São Paulo, SP (Brazil); Kulikowski, Leslie Domenici [Universidade de São Paulo, São Paulo, SP (Brazil); Departamento de Patologia - Laboratório de Citogenômica - LIM 03 - Universidade de São Paulo, São Paulo, SP (Brazil); Kim, Chong Ae [Universidade de São Paulo, São Paulo, SP (Brazil)

    2015-01-15

    Congenital heart defects (CHD) are the most prevalent group of structural abnormalities at birth and one of the main causes of infant morbidity and mortality. Studies have shown a contribution of the copy number variation in the genesis of cardiac malformations. Investigate gene copy number variation (CNV) in children with conotruncal heart defect. Multiplex ligation-dependent probe amplification (MLPA) was performed in 39 patients with conotruncal heart defect. Clinical and laboratory assessments were conducted in all patients. The parents of the probands who presented abnormal findings were also investigated. Gene copy number variation was detected in 7/39 patients: 22q11.2 deletion, 22q11.2 duplication, 15q11.2 duplication, 20p12.2 duplication, 19p deletion, 15q and 8p23.2 duplication with 10p12.31 duplication. The clinical characteristics were consistent with those reported in the literature associated with the encountered microdeletion/microduplication. None of these changes was inherited from the parents. Our results demonstrate that the technique of MLPA is useful in the investigation of microdeletions and microduplications in conotruncal congenital heart defects. Early diagnosis of the copy number variation in patients with congenital heart defect assists in the prevention of morbidity and decreased mortality in these patients.

  14. Copy number variation associates with mortality in long-lived individuals

    DEFF Research Database (Denmark)

    Nygaard, Marianne; Debrabant, Birgit; Tan, Qihua

    2016-01-01

    Copy number variants (CNVs) represent a significant source of genetic variation in the human genome and have been implicated in numerous diseases and complex traits. To date, only a few studies have investigated the role of CNVs in human lifespan. To investigate the impact of CNVs on prospective...

  15. Subtelomeric Rearrangements and Copy Number Variations in People with Intellectual Disabilities

    Science.gov (United States)

    Christofolini, D. M.; De Paula Ramos, M. A.; Kulikowski, L. D.; Da Silva Bellucco, F. T.; Belangero, S. I. N.; Brunoni, D.; Melaragno, M. I.

    2010-01-01

    Background: The most prevalent type of structural variation in the human genome is represented by copy number variations that can affect transcription levels, sequence, structure and function of genes. Method: In the present study, we used the multiplex ligation-dependent probe amplification (MLPA) technique and quantitative PCR for the detection…

  16. 10 CFR 51.58 - Environmental report-number of copies; distribution.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Environmental report-number of copies; distribution. 51.58... Implementing Section 102(2) Environmental Reports-Production and Utilization Facilities § 51.58 Environmental... appropriate, of an environmental report or any supplement to an environmental report. These reports must...

  17. Pyruvate Kinase and Fcγ Receptor Gene Copy Numbers Associated With Malaria Phenotypes.

    Science.gov (United States)

    Faik, Imad; van Tong, Hoang; Lell, Bertrand; Meyer, Christian G; Kremsner, Peter G; Velavan, Thirumalaisamy P

    2017-07-15

    Genetic factors are associated with susceptibility to many infectious diseases and may be determinants of clinical progression. Gene copy number variation (CNV) has been shown to be associated with phenotypes of numerous diseases, including malaria. We quantified gene copy numbers of the pyruvate kinase, liver, and red blood cell (PKLR) gene as well as of the Fcγ receptor 2A and Fcγ receptor 2C (FCGR2A, FCGR2C) and Fcγ receptor 3 (FCGR3) genes using real-time quantitative polymerase chain reaction (RT-qPCR) assays in Gabonese children with severe (n = 184) or and mild (n = 189) malaria and in healthy Gabonese and white individuals (n = 76 each). The means of PKLR, FCGR2A, FCGR2C, and FCGR3 copy numbers were significantly higher among children with severe malaria compared to those with mild malaria (P malaria severity. Copy numbers of the FCGR2A and FCGR2C genes were significantly lower (P = .005) in Gabonese individuals compared with white individuals. In conclusion, CNV of the PKLR, FCGR2A, FCGR2C, and FCGR3 genes is associated with malaria severity, and our results provide evidence for a role of CNV in host responses to malaria. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

  18. Copy number variation in obsessive-compulsive disorder and tourette syndrome: A cross-disorder study

    NARCIS (Netherlands)

    L.M. McGrath; D. Yu (D.); C.R. Marshall (Christian); L.K. Davis (Lea); B. Thiruvahindrapuram (Bhooma); B. Li (Bingbin); C. Cappi (Carolina); G. Gerber (Gloria); A. de Wolf (Anneke); F.A. Schroeder (Frederick); L. Osiecki (Lisa); C. O'Dushlaine (Colm); A. Kirby (Andrew); C. Illmann (Cornelia); S. Haddad (Stephen); P. Gallagher (Patience); J. Fagerness (Jesen); C.L. Barr; L. Bellodi (Laura); F. Benarroch (Fortu); O.J. Bienvenu (Oscar); D.W. Black (Donald W); J. Bloch (Jocelyne); R.D. Bruun (Ruth); C.L. Budman (Cathy); B. Camarena (Beatriz); D. Cath (Daniëlle); M.C. Cavallini (Maria); S. Chouinard; V. Coric (Vladimir); C. Cullen; R. Delorme (Richard); D.A.J.P. Denys (Damiaan); E.M. Derks (Eske); Y. Dion (Yves); M.C. Rosário (Maria); C.E. Eapen (Chundamannil Eapen); P. Evans; P. Falkai (Peter); T.V. Fernandez (Thomas); H. Garrido (Helena); D. Geller (Daniel); H.J. Grabe (Hans Jörgen); M. Grados (Marco); B.D. Greenberg (Benjamin); V. Gross-Tsur (Varda); E. Grünblatt (Edna); M.L. Heiman (Mark); S.M.J. Hemmings (Sian); L.D. Herrera (Luis); A.G. Hounie (Ana); J. Jankovic (Joseph); J.L. Kennedy; R.A. King; R. Kurlan; N. Lanzagorta (Nuria); M. Leboyer (Marion); J.F. Leckman; L. Lennertz (Leonhard); C. Lochner (Christine); T.L. Lowe (Thomas); H.N. Lyon (Helen); F. MacCiardi (Fabio); W. Maier (Wolfgang); J.T. McCracken (James); W.M. McMahon (William); D.L. Murphy (Dennis); A.L. Naarden (Allan); E. Nurmi (Erika); A.J. Pakstis; C. Pato (Carlos); C. Pato (Carlos); J. Piacentini (John); C. Pittenger (Christopher); M.N. Pollak (Michael); V.I. Reus (Victor); M.A. Richter (Margaret); M. Riddle (Mark); M.M. Robertson; D. Rosenberg (David); G.A. Rouleau; S. Ruhrmann (Stephan); A.S. Sampaio (Aline); J. Samuels (Jonathan); P. Sandor (Paul); B. Sheppard (Brooke); H.S. Singer (Harvey); J.H. Smit (Jan); D.J. Stein (Dan); J.A. Tischfield (Jay); H. Vallada (Homero); J. Veenstra-Vanderweele (Jeremy); S. Walitza (Susanne); Y. Wang (Ying); A. Wendland (Annika); Y.Y. Shugart; E.C. Miguel (Euripedes); H. Nicolini (Humberto); B.A. Oostra (Ben); R. Moessner (Rainald); M. Wagner (Michael); A. Ruiz-Linares (Andres); P. Heutink (Peter); G. Nestadt (Gerald); N.B. Freimer (Nelson); T.L. Petryshen (Tracey); D. Posthuma (Danielle); M.A. Jenike (Michael); N.J. Cox (Nancy); G.L. Hanna (Gregory); H. Brentani (Helena); S.W. Scherer (Stephen); P.D. Arnold (Paul); S.E. Stewart; C. Mathews; J.A. Knowles (James A); E.H. Cook (Edwin); D.L. Pauls (David); K. Wang (Kai); J.M. Scharf; B.M. Neale (Benjamin)

    2014-01-01

    textabstractObjective Obsessive-compulsive disorder (OCD) and Tourette syndrome (TS) are heritable neurodevelopmental disorders with a partially shared genetic etiology. This study represents the first genome-wide investigation of large (>500 kb), rare (<1%) copy number variants (CNVs) in OCD and

  19. Copy number variants on the X chromosome in women with primary ovarian insufficiency

    NARCIS (Netherlands)

    Knauff, Erik A. H.; Blauw, Hylke M.; Pearson, Peter L.; Kok, Klaas; Wijmenga, Cisca; Veldink, Jan H.; van den Berg, Leonard H.; Bouchard, Philippe; Fauser, Bart C. J. M.; Franke, Lude

    2011-01-01

    Objective: To investigate whether submicroscopic copy number variants (CNVs) on the X chromosome can be identified in women with primary ovarian insufficiency (POI), defined as spontaneous secondary amenorrhea before 40 years of age accompanied by follicle-stimulating hormone levels above 40 IU/L on

  20. Decreased mtDNA Copy Number of Gastric Cancer: a New Tumor Marker?

    Institute of Scientific and Technical Information of China (English)

    FanLi; XiaosongWang; ChengboHan; JieLin

    2004-01-01

    OBJECTIVE To explore the relationship between mtDNA (mitochondrial DNA) and gastric cancer by comparing the difference of mtDNA copy number in gastric cancers and paracancerous tissues.METHODS The HV1 (hypervariable region) and HV2 of the mitochondrial Dloop region from 20 cases of gastric cancer and 20 paracancerous tissues were amplified by PCR with 13-actin serving as a quantitative standard marker. The products were separated by polyacrylamide gel electrophoresis (PAGE) and silver stained in order to compare the difference in mtDNA copy number between gastric cancers and paracancerous tissues. The mtDNA copy number was determined for gastric cancer shaving various pathological characteristics and the results compared with previous immunohistochemical staininq of the tumors,RESULTS There was a significantly quantitative difference in HV1, HV2 (standardized with β-actin) between gastric cancers and paracancerous tissues (P0.05).CONCLUSION The occurrence of gastric cancer was closely associated with decreased mtDNA copy number, which may be a new tumor marker.

  1. rSW-seq: Algorithm for detection of copy number alterations in deep sequencing data

    Directory of Open Access Journals (Sweden)

    Kim Tae-Min

    2010-08-01

    Full Text Available Abstract Background Recent advances in sequencing technologies have enabled generation of large-scale genome sequencing data. These data can be used to characterize a variety of genomic features, including the DNA copy number profile of a cancer genome. A robust and reliable method for screening chromosomal alterations would allow a detailed characterization of the cancer genome with unprecedented accuracy. Results We develop a method for identification of copy number alterations in a tumor genome compared to its matched control, based on application of Smith-Waterman algorithm to single-end sequencing data. In a performance test with simulated data, our algorithm shows >90% sensitivity and >90% precision in detecting a single copy number change that contains approximately 500 reads for the normal sample. With 100-bp reads, this corresponds to a ~50 kb region for 1X genome coverage of the human genome. We further refine the algorithm to develop rSW-seq, (recursive Smith-Waterman-seq to identify alterations in a complex configuration, which are commonly observed in the human cancer genome. To validate our approach, we compare our algorithm with an existing algorithm using simulated and publicly available datasets. We also compare the sequencing-based profiles to microarray-based results. Conclusion We propose rSW-seq as an efficient method for detecting copy number changes in the tumor genome.

  2. Copy number variation in obsessive-compulsive disorder and tourette syndrome : a cross-disorder study

    NARCIS (Netherlands)

    McGrath, Lauren M; Yu, Dongmei; Marshall, Christian; Davis, Lea K; Thiruvahindrapuram, Bhooma; Li, Bingbin; Cappi, Carolina; Gerber, Gloria; Wolf, Aaron; Schroeder, Frederick A; Osiecki, Lisa; O'Dushlaine, Colm; Kirby, Andrew; Illmann, Cornelia; Haddad, Stephen; Gallagher, Patience; Fagerness, Jesen A; Barr, Cathy L; Bellodi, Laura; Benarroch, Fortu; Bienvenu, O Joseph; Black, Donald W; Bloch, Michael H; Bruun, Ruth D; Budman, Cathy L; Camarena, Beatriz; Cath, Danielle C; Cavallini, Maria C; Chouinard, Sylvain; Coric, Vladimir; Cullen, Bernadette; Delorme, Richard; Denys, D.; Derks, Eske M; Dion, Yves; Rosário, Maria C; Eapen, Valsama; Evans, Patrick; Falkai, Peter; Fernandez, Thomas V; Garrido, Helena; Geller, Daniel; Grabe, Hans J; Grados, Marco A; Greenberg, Benjamin D; Gross-Tsur, Varda; Grünblatt, Edna; Heiman, Gary A; Hemmings, Sian M J; Herrera, Luis D; Hounie, Ana G; Jankovic, Joseph; Kennedy, James L; King, Robert A; Kurlan, Roger; Lanzagorta, Nuria; Leboyer, Marion; Leckman, James F; Lennertz, Leonhard; Lochner, Christine; Lowe, Thomas L; Lyon, Gholson J; Macciardi, Fabio; Maier, Wolfgang; McCracken, James T; McMahon, William; Murphy, Dennis L; Naarden, Allan L; Neale, Benjamin M; Nurmi, Erika; Pakstis, Andrew J; Pato, Michele T; Pato, Carlos N; Piacentini, John; Pittenger, Christopher; Pollak, Yehuda; Reus, Victor I; Richter, Margaret A; Riddle, Mark; Robertson, Mary M; Rosenberg, David; Rouleau, Guy A; Ruhrmann, Stephan; Sampaio, Aline S; Samuels, Jack; Sandor, Paul; Sheppard, Brooke; Singer, Harvey S; Smit, Jan H; Stein, Dan J; Tischfield, Jay A; Vallada, Homero; Veenstra-VanderWeele, Jeremy; Walitza, Susanne; Wang, Ying; Wendland, Jens R; Shugart, Yin Yao; Miguel, Euripedes C; Nicolini, Humberto; Oostra, Ben A; Moessner, Rainald; Wagner, Michael; Ruiz-Linares, Andres; Heutink, Peter; Nestadt, Gerald; Freimer, Nelson; Petryshen, Tracey; Posthuma, Danielle; Jenike, Michael A; Cox, Nancy J; Hanna, Gregory L; Brentani, Helena; Scherer, Stephen W; Arnold, Paul D; Stewart, S Evelyn; Mathews, Carol A; Knowles, James A; Cook, Edwin H; Pauls, David L; Wang, Kai; Scharf, Jeremiah M

    2014-01-01

    OBJECTIVE: Obsessive-compulsive disorder (OCD) and Tourette syndrome (TS) are heritable neurodevelopmental disorders with a partially shared genetic etiology. This study represents the first genome-wide investigation of large (>500 kb), rare (<1%) copy number variants (CNVs) in OCD and the largest g

  3. Copy number variation in obsessive-compulsive disorder and tourette syndrome : a cross-disorder study

    NARCIS (Netherlands)

    McGrath, Lauren M; Yu, Dongmei; Marshall, Christian; Davis, Lea K; Thiruvahindrapuram, Bhooma; Li, Bingbin; Cappi, Carolina; Gerber, Gloria; Wolf, Aaron; Schroeder, Frederick A; Osiecki, Lisa; O'Dushlaine, Colm; Kirby, Andrew; Illmann, Cornelia; Haddad, Stephen; Gallagher, Patience; Fagerness, Jesen A; Barr, Cathy L; Bellodi, Laura; Benarroch, Fortu; Bienvenu, O Joseph; Black, Donald W; Bloch, Michael H; Bruun, Ruth D; Budman, Cathy L; Camarena, Beatriz; Cath, Danielle C|info:eu-repo/dai/nl/194111423; Cavallini, Maria C; Chouinard, Sylvain; Coric, Vladimir; Cullen, Bernadette; Delorme, Richard; Denys, Damiaan; Derks, Eske M; Dion, Yves; Rosário, Maria C; Eapen, Valsama; Evans, Patrick; Falkai, Peter; Fernandez, Thomas V; Garrido, Helena; Geller, Daniel; Grabe, Hans J; Grados, Marco A; Greenberg, Benjamin D; Gross-Tsur, Varda; Grünblatt, Edna; Heiman, Gary A; Hemmings, Sian M J; Herrera, Luis D; Hounie, Ana G; Jankovic, Joseph; Kennedy, James L; King, Robert A; Kurlan, Roger; Lanzagorta, Nuria; Leboyer, Marion; Leckman, James F; Lennertz, Leonhard; Lochner, Christine; Lowe, Thomas L; Lyon, Gholson J; Macciardi, Fabio; Maier, Wolfgang; McCracken, James T; McMahon, William; Murphy, Dennis L; Naarden, Allan L; Neale, Benjamin M; Nurmi, Erika; Pakstis, Andrew J; Pato, Michele T; Pato, Carlos N; Piacentini, John; Pittenger, Christopher; Pollak, Yehuda; Reus, Victor I; Richter, Margaret A; Riddle, Mark; Robertson, Mary M; Rosenberg, David; Rouleau, Guy A; Ruhrmann, Stephan; Sampaio, Aline S; Samuels, Jack; Sandor, Paul; Sheppard, Brooke; Singer, Harvey S; Smit, Jan H|info:eu-repo/dai/nl/113700644; Stein, Dan J; Tischfield, Jay A; Vallada, Homero; Veenstra-VanderWeele, Jeremy; Walitza, Susanne; Wang, Ying; Wendland, Jens R; Shugart, Yin Yao; Miguel, Euripedes C; Nicolini, Humberto; Oostra, Ben A; Moessner, Rainald; Wagner, Michael; Ruiz-Linares, Andres; Heutink, Peter; Nestadt, Gerald; Freimer, Nelson; Petryshen, Tracey; Posthuma, Danielle; Jenike, Michael A; Cox, Nancy J; Hanna, Gregory L; Brentani, Helena; Scherer, Stephen W; Arnold, Paul D; Stewart, S Evelyn; Mathews, Carol A; Knowles, James A; Cook, Edwin H; Pauls, David L; Wang, Kai; Scharf, Jeremiah M

    OBJECTIVE: Obsessive-compulsive disorder (OCD) and Tourette syndrome (TS) are heritable neurodevelopmental disorders with a partially shared genetic etiology. This study represents the first genome-wide investigation of large (>500 kb), rare (<1%) copy number variants (CNVs) in OCD and the largest

  4. Copy number polymorphisms in new HapMap III and Singapore populations.

    Science.gov (United States)

    Ku, Chee-Seng; Teo, Shu-Mei; Naidoo, Nasheen; Sim, Xueling; Teo, Yik-Ying; Pawitan, Yudi; Seielstad, Mark; Chia, Kee-Seng; Salim, Agus

    2011-08-01

    Copy number variations can be identified using newer genotyping arrays with higher single nucleotide polymorphisms (SNPs) density and copy number probes accompanied by newer algorithms. McCarroll et al. (2008) applied these to the HapMap II samples and identified 1316 copy number polymorphisms (CNPs). In our study, we applied the same approach to 859 samples from three Singapore populations and seven HapMap III populations. Approximately 50% of the 1291 autosomal CNPs were found to be polymorphic only in populations of non-African ancestry. Pairwise comparisons among the 10 populations showed substantial differences in the CNPs frequencies. Additionally, 698 CNPs showed significant differences with false discovery rate (FDR)macular degeneration), GSTTI (metabolism of various carcinogenic compounds and cancers) and UGT2B17 (prostate cancer and graft-versus-host disease). The correlations between CNPs and genome-wide association studies-SNPs were investigated and several loci, which were previously unreported, that may potentially be implicated in complex diseases and traits were found; for example, childhood acute lymphoblastic leukaemia, age-related macular degeneration, breast cancer, response to antipsychotic treatment, rheumatoid arthritis and type-1 diabetes. Additionally, we also found 5014 novel copy number loci that have not been reported previously by McCarroll et al. (2008) in the 10 populations.

  5. Copy number variation in obsessive-compulsive disorder and tourette syndrome : a cross-disorder study

    NARCIS (Netherlands)

    McGrath, Lauren M; Yu, Dongmei; Marshall, Christian; Davis, Lea K; Thiruvahindrapuram, Bhooma; Li, Bingbin; Cappi, Carolina; Gerber, Gloria; Wolf, Aaron; Schroeder, Frederick A; Osiecki, Lisa; O'Dushlaine, Colm; Kirby, Andrew; Illmann, Cornelia; Haddad, Stephen; Gallagher, Patience; Fagerness, Jesen A; Barr, Cathy L; Bellodi, Laura; Benarroch, Fortu; Bienvenu, O Joseph; Black, Donald W; Bloch, Michael H; Bruun, Ruth D; Budman, Cathy L; Camarena, Beatriz; Cath, Danielle C; Cavallini, Maria C; Chouinard, Sylvain; Coric, Vladimir; Cullen, Bernadette; Delorme, Richard; Denys, Damiaan; Derks, Eske M; Dion, Yves; Rosário, Maria C; Eapen, Valsama; Evans, Patrick; Falkai, Peter; Fernandez, Thomas V; Garrido, Helena; Geller, Daniel; Grabe, Hans J; Grados, Marco A; Greenberg, Benjamin D; Gross-Tsur, Varda; Grünblatt, Edna; Heiman, Gary A; Hemmings, Sian M J; Herrera, Luis D; Hounie, Ana G; Jankovic, Joseph; Kennedy, James L; King, Robert A; Kurlan, Roger; Lanzagorta, Nuria; Leboyer, Marion; Leckman, James F; Lennertz, Leonhard; Lochner, Christine; Lowe, Thomas L; Lyon, Gholson J; Macciardi, Fabio; Maier, Wolfgang; McCracken, James T; McMahon, William; Murphy, Dennis L; Naarden, Allan L; Neale, Benjamin M; Nurmi, Erika; Pakstis, Andrew J; Pato, Michele T; Pato, Carlos N; Piacentini, John; Pittenger, Christopher; Pollak, Yehuda; Reus, Victor I; Richter, Margaret A; Riddle, Mark; Robertson, Mary M; Rosenberg, David; Rouleau, Guy A; Ruhrmann, Stephan; Sampaio, Aline S; Samuels, Jack; Sandor, Paul; Sheppard, Brooke; Singer, Harvey S; Smit, Jan H; Stein, Dan J; Tischfield, Jay A; Vallada, Homero; Veenstra-VanderWeele, Jeremy; Walitza, Susanne; Wang, Ying; Wendland, Jens R; Shugart, Yin Yao; Miguel, Euripedes C; Nicolini, Humberto; Oostra, Ben A; Moessner, Rainald; Wagner, Michael; Ruiz-Linares, Andres; Heutink, Peter; Nestadt, Gerald; Freimer, Nelson; Petryshen, Tracey; Posthuma, Danielle; Jenike, Michael A; Cox, Nancy J; Hanna, Gregory L; Brentani, Helena; Scherer, Stephen W; Arnold, Paul D; Stewart, S Evelyn; Mathews, Carol A; Knowles, James A; Cook, Edwin H; Pauls, David L; Wang, Kai; Scharf, Jeremiah M

    2014-01-01

    OBJECTIVE: Obsessive-compulsive disorder (OCD) and Tourette syndrome (TS) are heritable neurodevelopmental disorders with a partially shared genetic etiology. This study represents the first genome-wide investigation of large (>500 kb), rare (<1%) copy number variants (CNVs) in OCD and the largest g

  6. Copy number variation in obsessive-compulsive disorder and tourette syndrome: A cross-disorder study

    NARCIS (Netherlands)

    L.M. McGrath; D. Yu (D.); C.R. Marshall (Christian); L.K. Davis (Lea); B. Thiruvahindrapuram (Bhooma); B. Li (Bingbin); C. Cappi (Carolina); G. Gerber (Gloria); A. de Wolf (Anneke); F.A. Schroeder (Frederick); L. Osiecki (Lisa); C. O'Dushlaine (Colm); A. Kirby (Andrew); C. Illmann (Cornelia); S. Haddad (Stephen); P. Gallagher (Patience); J. Fagerness (Jesen); C.L. Barr; L. Bellodi (Laura); F. Benarroch (Fortu); O.J. Bienvenu (Oscar); D.W. Black (Donald W); J. Bloch (Jocelyne); R.D. Bruun (Ruth); C.L. Budman (Cathy); B. Camarena (Beatriz); D. Cath (Daniëlle); M.C. Cavallini (Maria); S. Chouinard; V. Coric (Vladimir); C. Cullen; R. Delorme (Richard); D.A.J.P. Denys (Damiaan); E.M. Derks (Eske); Y. Dion (Yves); M.C. Rosário (Maria); C.E. Eapen (Chundamannil Eapen); P. Evans; P. Falkai (Peter); T.V. Fernandez (Thomas); H. Garrido (Helena); D. Geller (Daniel); H.J. Grabe (Hans Jörgen); M. Grados (Marco); B.D. Greenberg (Benjamin); V. Gross-Tsur (Varda); E. Grünblatt (Edna); M.L. Heiman (Mark); S.M.J. Hemmings (Sian); L.D. Herrera (Luis); A.G. Hounie (Ana); J. Jankovic (Joseph); J.L. Kennedy; R.A. King; R. Kurlan; N. Lanzagorta (Nuria); M. Leboyer (Marion); J.F. Leckman; L. Lennertz (Leonhard); C. Lochner (Christine); T.L. Lowe (Thomas); H.N. Lyon (Helen); F. MacCiardi (Fabio); W. Maier (Wolfgang); J.T. McCracken (James); W.M. McMahon (William); D.L. Murphy (Dennis); A.L. Naarden (Allan); E. Nurmi (Erika); A.J. Pakstis; C. Pato (Carlos); C. Pato (Carlos); J. Piacentini (John); C. Pittenger (Christopher); M.N. Pollak (Michael); V.I. Reus (Victor); M.A. Richter (Margaret); M. Riddle (Mark); M.M. Robertson; D. Rosenberg (David); G.A. Rouleau; S. Ruhrmann (Stephan); A.S. Sampaio (Aline); J. Samuels (Jonathan); P. Sandor (Paul); B. Sheppard (Brooke); H.S. Singer (Harvey); J.H. Smit (Jan); D.J. Stein (Dan); J.A. Tischfield (Jay); H. Vallada (Homero); J. Veenstra-Vanderweele (Jeremy); S. Walitza (Susanne); Y. Wang (Ying); A. Wendland (Annika); Y.Y. Shugart; E.C. Miguel (Euripedes); H. Nicolini (Humberto); B.A. Oostra (Ben); R. Moessner (Rainald); M. Wagner (Michael); A. Ruiz-Linares (Andres); P. Heutink (Peter); G. Nestadt (Gerald); N.B. Freimer (Nelson); T.L. Petryshen (Tracey); D. Posthuma (Danielle); M.A. Jenike (Michael); N.J. Cox (Nancy); G.L. Hanna (Gregory); H. Brentani (Helena); S.W. Scherer (Stephen); P.D. Arnold (Paul); S.E. Stewart; C. Mathews; J.A. Knowles (James A); E.H. Cook (Edwin); D.L. Pauls (David); K. Wang (Kai); J.M. Scharf; B.M. Neale (Benjamin)

    2014-01-01

    textabstractObjective Obsessive-compulsive disorder (OCD) and Tourette syndrome (TS) are heritable neurodevelopmental disorders with a partially shared genetic etiology. This study represents the first genome-wide investigation of large (>500 kb), rare (<1%) copy number variants (CNVs) in OCD and th

  7. 17 CFR 230.424 - Filing of prospectuses, number of copies.

    Science.gov (United States)

    2010-04-01

    ... asset-backed securities on a delayed basis under § 230.415(a)(1)(x) that is required to be filed... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Filing of prospectuses, number of copies. 230.424 Section 230.424 Commodity and Securities Exchanges SECURITIES AND EXCHANGE...

  8. Genome-wide analysis of copy number variants in attention deficit hyperactivity disorder: the role of rare variants and duplications at 15q13.3.

    NARCIS (Netherlands)

    Williams, N.M.; Franke, B.; Mick, E.; Anney, R.J.; Freitag, C.M.; Gill, M.; Thapar, A.; O'Donovan, M.C.; Owen, M.J.; Holmans, P.; Kent, L.; Middleton, F.; Zhang-James, Y.; Liu, L.; Meyer, J.; Nguyen, T.T.M.; Romanos, J.; Romanos, M.; Seitz, C.; Renner, T.J.; Walitza, S.; Warnke, A.; Palmason, H.; Buitelaar, J.K.; Rommelse, N.N.; Arias Vasquez, A.; Hawi, Z.; Langley, K.; Sergeant, J.A.; Steinhausen, H.C.; Roeyers, H.; Biederman, J.; Zaharieva, I.; Hakonarson, H.; Elia, J.; Lionel, A.C.; Crosbie, J.; Marshall, C.R.; Schachar, R.; Scherer, S.W.; Todorov, A.; Smalley, S.L.; Loo, S.; Nelson, S.; Shtir, C.; Asherson, P.; Reif, A.; Lesch, K.P.; Faraone, S.V.

    2012-01-01

    OBJECTIVE: Attention deficit hyperactivity disorder (ADHD) is a common, highly heritable psychiatric disorder. Because of its multifactorial etiology, however, identifying the genes involved has been difficult. The authors followed up on recent findings suggesting that rare copy number variants (CNV

  9. Copy number variation of functional RBMY1 is associated with sperm motility: an azoospermia factor-linked candidate for asthenozoospermia.

    Science.gov (United States)

    Yan, Yuanlong; Yang, Xiling; Liu, Yunqiang; Shen, Ying; Tu, Wenling; Dong, Qiang; Yang, Dong; Ma, Yongyi; Yang, Yuan

    2017-05-12

    population. A difference in the distribution of RBMY1 copy number was observed between the group with normal sperm motility and the group with asthenozoospermia. A positive correlation between the RBMY1 copy dosage and sperm motility was identified, and the males with fewer than six copies of RBMY1 showed an elevated risk for asthenozoospermia relative to those with six RBMY1 copies, the most common dosage in the population. The RBMY1 copy dosage was positively correlated with its mRNA and protein level in the testis. Sperm with high motility were found to carry more RBMY1 protein than those with relatively low motility. The RBMY1 protein was confirmed to predominantly localize in the neck and mid-piece region of sperm as well as the principal piece of the sperm tail. Our population study completes a chain of evidence suggesting that RBMY1 influences the susceptibility of males to asthenozoospermia by modulating sperm motility. High sequence similarity between the RBMY1 functional copies and a large number of pseudogenes potentially reduces the accuracy of the copy number detection. The mechanism underlying the CNV in RBMY1 is still unclear, and the effect of the structural variations in the RBMY1 copy cluster on the copy dosage of other protein-coding genes located in the region cannot be excluded, which may potentially bias our observations. Asthenozoospermia is a multi-factor complex disease with a limited number of proven susceptibility genes. This study identified a novel genomic candidate independently contributing to the condition, enriching our understanding of the role of AZF-linked genes in male reproduction. Our finding provides insight into the physiological and pathological characteristics of RBMY1 in terms of sperm motility, supplies persuasive evidence of the significance of RBMY1 copy number analysis in the clinical counselling of male infertility resulting from asthenozoospermia. This work was funded by the National Natural Science Foundation of China (Nos

  10. CBF2A-CBF4B genomic region copy numbers alongside the circadian clock play key regulatory mechanisms driving expression of FR-H2 CBFs.

    Science.gov (United States)

    Dhillon, Taniya; Morohashi, Kengo; Stockinger, Eric J

    2017-06-01

    The C-Repeat Binding Factors (CBFs) are DNA-binding transcriptional activators that were identified using Arabidopsis thaliana. In barley, Hordeum vulgare, a cluster of CBF genes reside at FROST RESISTANCE-H2, one of two loci having major effects on winter-hardiness. FR-H2 was revealed in a population derived from the winter barley 'Nure' and the spring barley 'Trèmois'. 'Nure' harbors two to three copies of CBF2A and CBF4B as a consequence of tandem iteration of the genomic region encompassing these genes whereas 'Trèmois' harbors single copies, and these copy number differences are associated with their transcript level differences. Here we explore further the relationship between FR-H2 CBF gene copy number and transcript levels using 'Admire', a winter barley accumulating FR-H2 CBF gene transcripts to very high levels, and a group of lines related to 'Admire' through descent. DNA blot hybridization indicated the CBF2A-CBF4B genomic region is present in 7-8 copies in 'Admire' and is highly variable in copy number across the lines related to 'Admire'. At normal growth temperatures transcript levels of CBF12, CBF14, and CBF16 were higher in lines having greater CBF2A-CBF4B genomic region copy numbers than in lines having fewer copy numbers at peak expression level time points controlled by the circadian clock. Chromatin immunoprecipitation indicated CBF2 was at the CBF12 and CBF16 promoters at normal growth temperatures. These data support a scenario in which CBF2A-CBF4B genomic region copy numbers affect expression of other FR-H2 CBFs through a mechansim in which these other FR-H2 CBFs are activated by those in the copy number variable unit.

  11. Expression, tandem repeat copy number variation and stability of four macrosatellite arrays in the human genome

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    Chadwick Brian P

    2010-11-01

    Full Text Available Abstract Background Macrosatellites are some of the largest variable number tandem repeats in the human genome, but what role these unusual sequences perform is unknown. Their importance to human health is clearly demonstrated by the 4q35 macrosatellite D4Z4 that is associated with the onset of the muscle degenerative disease facioscapulohumeral muscular dystrophy. Nevertheless, many other macrosatellite arrays in the human genome remain poorly characterized. Results Here we describe the organization, tandem repeat copy number variation, transmission stability and expression of four macrosatellite arrays in the human genome: the TAF11-Like array located on chromosomes 5p15.1, the SST1 arrays on 4q28.3 and 19q13.12, the PRR20 array located on chromosome 13q21.1, and the ZAV array at 9q32. All are polymorphic macrosatellite arrays that at least for TAF11-Like and SST1 show evidence of meiotic instability. With the exception of the SST1 array that is ubiquitously expressed, all are expressed at high levels in the testis and to a lesser extent in the brain. Conclusions Our results extend the number of characterized macrosatellite arrays in the human genome and provide the foundation for formulation of hypotheses to begin assessing their functional role in the human genome.

  12. Genomic Pathology of SLE-Associated Copy-Number Variation at the FCGR2C/FCGR3B/FCGR2B Locus

    OpenAIRE

    Mueller, Michael; Barros, Paula; Witherden, Abigail S.; Roberts, Amy L.; Zhang, Zhou; Schaschl, Helmut; Yu, Chack-Yung; Hurles, Matthew E.; Schaffner, Catherine; Floto, R. Andres; Game, Laurence; Steinberg, Karyn Meltz; Wilson, Richard K.; Graves, Tina A.; Eichler, Evan E.

    2013-01-01

    Reduced FCGR3B copy number is associated with increased risk of systemic lupus erythematosus (SLE). The five FCGR2/FCGR3 genes are arranged across two highly paralogous genomic segments on chromosome 1q23. Previous studies have suggested mechanisms for structural rearrangements at the FCGR2/FCGR3 locus and have proposed mechanisms whereby altered FCGR3B copy number predisposes to autoimmunity, but the high degree of sequence similarity between paralogous segments has prevented precise definit...

  13. American College of Medical Genetics standards and guidelines for interpretation and reporting of postnatal constitutional copy number variants.

    Science.gov (United States)

    Kearney, Hutton M; Thorland, Erik C; Brown, Kerry K; Quintero-Rivera, Fabiola; South, Sarah T

    2011-07-01

    Genomic microarrays used to assess DNA copy number are now recommended as first-tier tests for the postnatal evaluation of individuals with intellectual disability, autism spectrum disorders, and/or multiple congenital anomalies. Application of this technology has resulted in the discovery of widespread copy number variation in the human genome, both polymorphic variation in healthy individuals and novel pathogenic copy number imbalances. To assist clinical laboratories in the evaluation of copy number variants and to promote consistency in interpretation and reporting of genomic microarray results, the American College of Medical Genetics has developed the following professional guidelines for the interpretation and reporting of copy number variation. These guidelines apply primarily to evaluation of constitutional copy number variants detected in the postnatal setting.

  14. Validity of Low Copy Number Typing and Applications to Forensic Science

    OpenAIRE

    Budowle, Bruce; Eisenberg, Arthur J.; Van Daal, Angela

    2009-01-01

    Low copy number (LCN) typing, particularly for current short tandem repeat (STR) typing, refers to the analysis of any sample that contains less than 200 pg of template DNA. Generally, LCN typing simply can be defined as the analysis of any DNA sample where the results are below the stochastic threshold for reliable interpretation. There are a number of methodologies to increase sensitivity of detection to enable LCN typing. These approaches encompass modifications during the polymerase chain...

  15. Copy number alteration and uniparental disomy analysis categorizes Japanese papillary thyroid carcinomas into distinct groups.

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    Michiko Matsuse

    Full Text Available The aim of the present study was to investigate chromosomal aberrations in sporadic Japanese papillary thyroid carcinomas (PTCs, concomitant with the analysis of oncogene mutational status. Twenty-five PTCs (11 with BRAF(V600E, 4 with RET/PTC1, and 10 without mutation in HRAS, KRAS, NRAS, BRAF, RET/PTC1, or RET/PTC3 were analyzed using Genome-Wide Human SNP Array 6.0 which allows us to detect copy number alteration (CNA and uniparental disomy (UPD, also referred to as copy neutral loss of heterozygosity, in a single experiment. The Japanese PTCs showed relatively stable karyotypes. Seven cases (28% showed CNA(s, and 6 (24% showed UPD(s. Interestingly, CNA and UPD were rarely overlapped in the same tumor; the only one advanced case showed both CNA and UPD with a highly complex karyotype. Thirteen (52% showed neither CNA nor UPD. Regarding CNA, deletions tended to be more frequent than amplifications. The most frequent and recurrent region was the deletion in chromosome 22; however, it was found in only 4 cases (16%. The degree of genomic instability did not depend on the oncogene status. However, in oncogene-positive cases (BRAF(V600E and RET/PTC1, tumors with CNA/UPD were less frequent (5/15, 33%, whereas tumors with CNA/UPD were more frequent in oncogene-negative cases (7/10, 70%, suggesting that chromosomal aberrations may play a role in the development of PTC, especially in oncogene-negative tumors. These data suggest that Japanese PTCs may be classified into three distinct groups: CNA(+, UPD(+, and no chromosomal aberrations. BRAF(V600E mutational status did not correlate with any parameters of chromosomal defects.

  16. A copy number variation in human NCF1 and its pseudogenes

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    Chambers Isfahan

    2010-02-01

    Full Text Available Abstract Background Neutrophil cytosolic factor-1 (NCF1 is a component of NADPH oxidase. The NCF1 gene colocalizes with two pseudogenes (NCF1B and NCF1C. These two pseudogenes have a GT deletion in exon 2, resulting in a frameshift and an early stop codon. Here, we report a copy number variation (CNV of the NCF1 pseudogenes and their alternative spliced expressions. Results We examined three normal populations (86 individuals. We observed the 2:2:2 pattern (NCF1B:NCF1:NCF1C in only 26 individuals. On average, each African- American has 1.4 ± 0.8 (Mean ± SD copies of NCF1B and 2.3 ± 0.6 copies of NCF1C; each Caucasian has 1.8 ± 0.7 copies of NCF1B and 1.9 ± 0.4 copies of NCF1C; and each Mexican has 1.6 ± 0.6 copies of NCF1B and 1.0 ± 0.4 copies of NCF1C. Mexicans have significantly less NCF1C copies than African-Americans (p = 6e-15 and Caucasians (p = 3e-11. Mendelian transmission of this CNV was observed in two CEPH pedigrees. Moreover, we cloned two alternative spliced transcripts generated from these two pseudogenes that adopt alternative exon-2 instead of their defective exon 2. The NCF1 pseudogene expression responded robustly to PMA induction during macrophage differentiation. NCF1B decreased from 32.9% to 8.3% in the cDNA pool transcribed from 3 gene copies. NCF1Ψs also displayed distinct expression patterns in different human tissues. Conclusions Our results suggest that these two pseudogenes may adopt an alternative exon-2 in different tissues and in response to external stimuli. The GT deletion is insufficient to define them as functionless pseudogenes; this CNV may have biological relevance.

  17. Tandem duplication and copy number polymorphism of the SRY gene in patients with sex chromosome anomalies and males exposed to natural background radiation.

    Science.gov (United States)

    Premi, Sanjay; Srivastava, Jyoti; Chandy, Sebastian Padinjarel; Ahmad, Jamal; Ali, Sher

    2006-02-01

    Mutations in the SRY gene encompassing the HMG box have been well characterized in gonadal dysgenesis, male infertility and other types of sex chromosome related anomalies (SCRA). However, no information is available on copy number status of this gene under such abnormal conditions. Employing 'Taqman Probe Assay' specific to the SRY gene, we screened 16 DNA samples from patients with SCRA and 36 samples from males exposed to high levels of natural background radiation (HNBR). Patients with SCRA showed 2-16 copies of the SRY gene of which, one, Oxen (49, XYYYY) had eight copies with sequences different from one another. Of the 36 HNBR samples, 12 had one copy whereas 24 harboured 2-8 copies of the SRY gene. A HNBR male 33F had one normal and one mutated copy of this gene. Analysis of 25 DNA samples from blood and semen of normal males showed only one copy of this gene. Despite multiple copies in affected males, fluorescence in-situ hybridization (FISH) with SRY probe detected a single signal on the Y chromosome in HNBR males suggesting its possible localized tandem duplication. Copy number status of the other Y-linked loci is envisaged to augment DNA diagnostics facilitating genetic counselling to affected patients.

  18. Genome-wide copy number profiling of mouse neural stem cells during differentiation

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    U. Fischer

    2015-09-01

    Full Text Available There is growing evidence that gene amplifications were present in neural stem and progenitor cells during differentiation. We used array-CGH to discover copy number changes including gene amplifications and deletions during differentiation of mouse neural stem cells using TGF-ß and FCS for differentiation induction. Array data were deposited in GEO (Gene Expression Omnibus, NCBI under accession number GSE35523. Here, we describe in detail the cell culture features and our TaqMan qPCR-experiments to validate the array-CGH analysis. Interpretation of array-CGH experiments regarding gene amplifications in mouse and further detailed analysis of amplified chromosome regions associated with these experiments were published by Fischer and colleagues in Oncotarget (Fischer et al., 2015. We provide additional information on deleted chromosome regions during differentiation and give an impressive overview on copy number changes during differentiation induction at a time line.

  19. Change and Significance of Mitochondrial DNA Copy Number in Esophageal Squamous Cell Carcinoma

    Institute of Scientific and Technical Information of China (English)

    Zongwen Liu; Zhihua Zhao; Qiumin Zhao; Shenglei Li; Dongling Gao; Xia Pang; Kuisheng Chen; Yunhan Zhang

    2007-01-01

    OBJECTIVE To compare the differences of mitochondrial DNA (mtDNA)copies among the tissues of esophageal squamous cell carcinoma (ESCC),para-neoplastic tissue and normal mucous membrane of the esophagus,and to study the relationship between the mtDNA and the occurrence and development of esophageal squamous cell carcinoma.METHODS The mtDNA copies of 42 specimens with the ESCC,paraneoplastic mucous tissue and normal mucous membrane of the esophagus were determined using real-time fluorescence quantitative PCR.The mtDNA was analyzed using agarose gel electrophoresis.RESULTS The mtDNA from all of the tissues (42/42) from the ESCC,para-neoplastic tissue and normal esophageal mucous membranes was analyzed.showing thal there were an average mtDNA copy number of 27.1894x106 μg DNA.9.4102x106 μg DNA and 5.9347x106 μg DNA,from the respective tissues.There were significant differences (F=27.83,P<0.05) in mtDNA copy number among the three.A positive band was shown at 403 bp after qel electrophoresis of the PCR products.and the lane where the ESCC mtDNA located was rather bright.which was in accordance with the result of the real-time PCR determination.CONCLUSION An increase in the mtDNA copy number is related to the occurrence and development of ESCC.

  20. Copy number variation of age-related macular degeneration relevant genes in the Korean population.

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    Jung Hyun Park

    Full Text Available PURPOSE: Studies that analyzed single nucleotide polymorphisms (SNP in various genes have shown that genetic factors are strongly associated with age-related macular degeneration (AMD susceptibility. Copy number variation (CNV may be an additional type of genetic variation that contributes to AMD pathogenesis. This study investigated CNV in 4 AMD-relevant genes in Korean AMD patients and control subjects. METHODS: Four CNV candidate regions located in AMD-relevant genes (VEGFA, ARMS2/HTRA1, CFH and VLDLR, were selected based on the outcomes of our previous study which elucidated common CNVs in the Asian populations. Real-time PCR based TaqMan Copy Number Assays were performed on CNV candidates in 273 AMD patients and 257 control subjects. RESULTS: The predicted copy number (PCN, 0, 1, 2 or 3+ of each region was called using the CopyCaller program. All candidate genes except ARMS2/HTRA1 showed CNV in at least one individual, in which losses of VEGFA and VLDLR represent novel findings in the Asian population. When the frequencies of PCN were compared, only the gain in VLDLR showed significant differences between AMD patients and control subjects (p = 0.025. Comparisons of the raw copy values (RCV revealed that 3 of 4 candidate genes showed significant differences (2.03 vs. 1.92 for VEGFA, p<0.01; 2.01 vs. 1.97 for CFH, p<0.01; 1.97 vs. 2.01, p<0.01 for ARMS2/HTRA1. CONCLUSION: CNVs located in AMD-relevant genes may be associated with AMD susceptibility. Further investigations encompassing larger patient cohorts are needed to elucidate the role of CNV in AMD pathogenesis.

  1. Differences in AMY1 Gene Copy Numbers Derived from Blood, Buccal Cells and Saliva Using Quantitative and Droplet Digital PCR Methods: Flagging the Pitfall

    Science.gov (United States)

    Ong, Siong Gim; Chan, Yiong Huak; Heng, Chew Kiat

    2017-01-01

    Introduction The human salivary (AMY1) gene, encoding salivary α-amylase, has variable copy number variants (CNVs) in the human genome. We aimed to determine if real-time quantitative polymerase chain reaction (qPCR) and the more recently available Droplet Digital PCR (ddPCR) can provide a precise quantification of the AMY1 gene copy number in blood, buccal cells and saliva samples derived from the same individual. Methods Seven participants were recruited and DNA was extracted from the blood, buccal cells and saliva samples provided by each participant. Taqman assay real-time qPCR and ddPCR were conducted to quantify AMY1 gene copy numbers. Statistical analysis was carried out to determine the difference in AMY1 gene copy number between the different biological specimens and different assay methods. Results We found significant within-individual difference (p<0.01) in AMY1 gene copy number between different biological samples as determined by qPCR. However, there was no significant within-individual difference in AMY1 gene copy number between different biological samples as determined by ddPCR. We also found that AMY1 gene copy number of blood samples were comparable between qPCR and ddPCR, while there is a significant difference (p<0.01) between AMY1 gene copy numbers measured by qPCR and ddPCR for both buccal swab and saliva samples. Conclusions Despite buccal cells and saliva samples being possible sources of DNA, it is pertinent that ddPCR or a single biological sample, preferably blood sample, be used for determining highly polymorphic gene copy numbers like AMY1, due to the large within-individual variability between different biological samples if real time qPCR is employed. PMID:28125683

  2. Accurate determination of plasmid copy number of flow-sorted cells using droplet digital PCR.

    Science.gov (United States)

    Jahn, Michael; Vorpahl, Carsten; Türkowsky, Dominique; Lindmeyer, Martin; Bühler, Bruno; Harms, Hauke; Müller, Susann

    2014-06-17

    Many biotechnological processes rely on the expression of a plasmid-based target gene. A constant and sufficient number of plasmids per cell is desired for efficient protein production. To date, only a few methods for the determination of plasmid copy number (PCN) are available, and most of them average the PCN of total populations disregarding heterogeneous distributions. Here, we utilize the highly precise quantification of DNA molecules by droplet digital PCR (ddPCR) and combine it with cell sorting using flow cytometry. A duplex PCR assay was set up requiring only 1000 sorted cells for precise determination of PCN. The robustness of this method was proven by thorough optimization of cell sorting, cell disruption, and PCR conditions. When non plasmid-harboring cells of Pseudomonas putida KT2440 were spiked with different dilutions of the expression plasmid pA-EGFP_B, a PCN from 1 to 64 could be accurately detected. As a proof of principle, induced cultures of P. putida KT2440 producing an EGFP-fused model protein by means of the plasmid pA-EGFP_B were investigated by flow cytometry and showed two distinct subpopulations, fluorescent and nonfluorescent cells. These two subpopulations were sorted for PCN determination with ddPCR. A remarkably diverging plasmid distribution was found within the population, with nonfluorescent cells showing a much lower PCN (≤1) than fluorescent cells (PCN of up to 5) under standard conditions.

  3. The potential role for use of mitochondrial DNA copy number as predictive biomarker in presbycusis

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    Falah M

    2016-10-01

    Full Text Available Masoumeh Falah,1,2 Massoud Houshmand,3 Mohammad Najafi,2 Maryam Balali,1 Saeid Mahmoudian,1 Alimohamad Asghari,4 Hessamaldin Emamdjomeh,1 Mohammad Farhadi1 1ENT and Head & Neck Research Center and Department, Iran University of Medical Sciences, Tehran, Iran; 2Cellular and Molecular Research Center, Biochemistry Department, Iran University of Medical Sciences, Tehran, Iran; 3Department of Medical Genetics, National Institute for Genetic Engineering and Biotechnology, Tehran, Iran; 4Skull base research center, Iran University of Medical Sciences, Tehran, Iran Objectives: Age-related hearing impairment, or presbycusis, is the most common communication disorder and neurodegenerative disease in the elderly. Its prevalence is expected to increase, due to the trend of growth of the elderly population. The current diagnostic test for detection of presbycusis is implemented after there has been a change in hearing sensitivity. Identification of a pre-diagnostic biomarker would raise the possibility of preserving hearing sensitivity before damage occurs. Mitochondrial dysfunction, including the production of reactive oxygen species and induction of expression of apoptotic genes, participates in the progression of presbycusis. Mitochondrial DNA sequence variation has a critical role in presbycusis. However, the nature of the relationship between mitochondrial DNA copy number, an important biomarker in many other diseases, and presbycusis is undetermined.Methods: Fifty-four subjects with presbycusis and 29 healthy controls were selected after ear, nose, throat examination and pure-tone audiometry. DNA was extracted from peripheral blood samples. The copy number of mitochondrial DNA relative to the nuclear genome was measured by quantitative real-time polymerase chain reaction.Results: Subjects with presbycusis had a lower median mitochondrial DNA copy number than healthy subjects and the difference was statistically significant (P=0.007. Mitochondrial DNA

  4. Association testing of copy number variants in schizophrenia and autism spectrum disorders

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    Crespi Bernard J

    2012-05-01

    Full Text Available Abstract Background Autism spectrum disorders and schizophrenia have been associated with an overlapping set of copy number variant loci, but the nature and degree of overlap in copy number variants (deletions compared to duplications between these two disorders remains unclear. Methods We systematically evaluated three lines of evidence: (1 the statistical bases for associations of autism spectrum disorders and schizophrenia with a set of the primary CNVs thus far investigated, from previous studies; (2 data from case series studies on the occurrence of these CNVs in autism spectrum disorders, especially among children, and (3 data on the extent to which the CNVs were associated with intellectual disability and developmental, speech, or language delays. We also conducted new analyses of existing data on these CNVs in autism by pooling data from seven case control studies. Results Four of the CNVs considered, dup 1q21.1, dup 15q11-q13, del 16p11.2, and dup 22q11.21, showed clear statistical evidence as autism risk factors, whereas eight CNVs, del 1q21.1, del 3q29, del 15q11.2, del 15q13.3, dup 16p11.2, dup 16p13.1, del 17p12, and del 22q11.21, were strongly statistically supported as risk factors for schizophrenia. Three of the CNVs, dup 1q21.1, dup 16p11.2, and dup 16p13.1, exhibited statistical support as risk factors for both autism and schizophrenia, although for each of these CNVs statistical significance was nominal for tests involving one of the two disorders. For the CNVs that were statistically associated with schizophrenia but were not statistically associated with autism, a notable number of children with the CNVs have been diagnosed with autism or ASD; children with these CNVs also demonstrate a high incidence of intellectual disability and developmental, speech, or language delays. Conclusions These findings suggest that although CNV loci notably overlap between autism and schizophrenia, the degree of strongly statistically

  5. Copy number variations in Saudi family with intellectual disability and epilepsy

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    Muhammad I. Naseer

    2016-10-01

    Full Text Available Abstract Background Epilepsy is genetically complex but common brain disorder of the world affecting millions of people with almost of all age groups. Novel Copy number variations (CNVs are considered as important reason for the numerous neurodevelopmental disorders along with intellectual disability and epilepsy. DNA array based studies contribute to explain a more severe clinical presentation of the disease but interoperation of many detected CNVs are still challenging. Results In order to study novel CNVs with epilepsy related genes in Saudi family with six affected and two normal individuals with several forms of epileptic seizures, intellectual disability (ID, and minor dysmorphism, we performed the high density whole genome Agilent sure print G3 Hmn CGH 2x 400 K array-CGH chips analysis. Our results showed de novo deletions, duplications and deletion plus duplication on differential chromosomal regions in the affected individuals that were not shown in the normal fathe and normal kids by using Agilent CytoGenomics 3.0.6.6 softwear. Copy number gain were observed in the chromosome 1, 16 and 22 with LCE3C, HPR, GSTT2, GSTTP2, DDT and DDTL genes respectively whereas the deletions observed in the chromosomal regions 8p23-p21 (4303127–4337759 and the potential gene in this region is CSMD1 (OMIM: 612279. Moreover, the array CGH results deletions and duplication were also validated by using primer design of deleted regions utilizing the flanked SNPs using simple PCR and also by using quantitative real time PCR. Conclusions We found some of the de novo deletions and duplication in our study in Saudi family with intellectual disability and epilepsy. Our results suggest that array-CGH should be used as a first line of genetic test for epilepsy except there is a strong indication for a monogenic syndrome. The advanced high through put array-CGH technique used in this study aim to collect the data base and to identify new mechanisms describing

  6. Understanding the impact of 1q21.1 copy number variant

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    Harvard Chansonette

    2011-08-01

    Full Text Available Abstract Background 1q21.1 Copy Number Variant (CNV is associated with a highly variable phenotype ranging from congenital anomalies, learning deficits/intellectual disability (ID, to a normal phenotype. Hence, the clinical significance of this CNV can be difficult to evaluate. Here we described the consequences of the 1q21.1 CNV on genome-wide gene expression and function of selected candidate genes within 1q21.1 using cell lines from clinically well described subjects. Methods and Results Eight subjects from 3 families were included in the study: six with a 1q21.1 deletion and two with a 1q21.1 duplication. High resolution Affymetrix 2.7M array was used to refine the 1q21.1 CNV breakpoints and exclude the presence of secondary CNVs of pathogenic relevance. Whole genome expression profiling, studied in lymphoblast cell lines (LBCs from 5 subjects, showed enrichment of genes from 1q21.1 in the top 100 genes ranked based on correlation of expression with 1q21.1 copy number. The function of two top genes from 1q21.1, CHD1L/ALC1 and PRKAB2, was studied in detail in LBCs from a deletion and a duplication carrier. CHD1L/ALC1 is an enzyme with a role in chromatin modification and DNA damage response while PRKAB2 is a member of the AMP kinase complex, which senses and maintains systemic and cellular energy balance. The protein levels for CHD1L/ALC1 and PRKAB2 were changed in concordance with their copy number in both LBCs. A defect in chromatin remodeling was documented based on impaired decatenation (chromatid untangling checkpoint (DCC in both LBCs. This defect, reproduced by CHD1L/ALC1 siRNA, identifies a new role of CHD1L/ALC1 in DCC. Both LBCs also showed elevated levels of micronuclei following treatment with a Topoisomerase II inhibitor suggesting increased DNA breaks. AMP kinase function, specifically in the deletion containing LBCs, was attenuated. Conclusion Our studies are unique as they show for the first time that the 1q21.1 CNV not only

  7. Microarray MAPH: accurate array-based detection of relative copy number in genomic DNA

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    Chan Alan

    2006-06-01

    Full Text Available Abstract Background Current methods for measurement of copy number do not combine all the desirable qualities of convenience, throughput, economy, accuracy and resolution. In this study, to improve the throughput associated with Multiplex Amplifiable Probe Hybridisation (MAPH we aimed to develop a modification based on the 3-Dimensional, Flow-Through Microarray Platform from PamGene International. In this new method, electrophoretic analysis of amplified products is replaced with photometric analysis of a probed oligonucleotide array. Copy number analysis of hybridised probes is based on a dual-label approach by comparing the intensity of Cy3-labelled MAPH probes amplified from test samples co-hybridised with similarly amplified Cy5-labelled reference MAPH probes. The key feature of using a hybridisation-based end point with MAPH is that discrimination of amplified probes is based on sequence and not fragment length. Results In this study we showed that microarray MAPH measurement of PMP22 gene dosage correlates well with PMP22 gene dosage determined by capillary MAPH and that copy number was accurately reported in analyses of DNA from 38 individuals, 12 of which were known to have Charcot-Marie-Tooth disease type 1A (CMT1A. Conclusion Measurement of microarray-based endpoints for MAPH appears to be of comparable accuracy to electrophoretic methods, and holds the prospect of fully exploiting the potential multiplicity of MAPH. The technology has the potential to simplify copy number assays for genes with a large number of exons, or of expanded sets of probes from dispersed genomic locations.

  8. Detection of clinically relevant exonic copy-number changes by array CGH.

    Science.gov (United States)

    Boone, Philip M; Bacino, Carlos A; Shaw, Chad A; Eng, Patricia A; Hixson, Patricia M; Pursley, Amber N; Kang, Sung-Hae L; Yang, Yaping; Wiszniewska, Joanna; Nowakowska, Beata A; del Gaudio, Daniela; Xia, Zhilian; Simpson-Patel, Gayle; Immken, LaDonna L; Gibson, James B; Tsai, Anne C-H; Bowers, Jennifer A; Reimschisel, Tyler E; Schaaf, Christian P; Potocki, Lorraine; Scaglia, Fernando; Gambin, Tomasz; Sykulski, Maciej; Bartnik, Magdalena; Derwinska, Katarzyna; Wisniowiecka-Kowalnik, Barbara; Lalani, Seema R; Probst, Frank J; Bi, Weimin; Beaudet, Arthur L; Patel, Ankita; Lupski, James R; Cheung, Sau Wai; Stankiewicz, Pawel

    2010-12-01

    Array comparative genomic hybridization (aCGH) is a powerful tool for the molecular elucidation and diagnosis of disorders resulting from genomic copy-number variation (CNV). However, intragenic deletions or duplications--those including genomic intervals of a size smaller than a gene--have remained beyond the detection limit of most clinical aCGH analyses. Increasing array probe number improves genomic resolution, although higher cost may limit implementation, and enhanced detection of benign CNV can confound clinical interpretation. We designed an array with exonic coverage of selected disease and candidate genes and used it clinically to identify losses or gains throughout the genome involving at least one exon and as small as several hundred base pairs in size. In some patients, the detected copy-number change occurs within a gene known to be causative of the observed clinical phenotype, demonstrating the ability of this array to detect clinically relevant CNVs with subkilobase resolution. In summary, we demonstrate the utility of a custom-designed, exon-targeted oligonucleotide array to detect intragenic copy-number changes in patients with various clinical phenotypes.

  9. The copy number of Epstein-Barr virus latent genome correlates with the oncogenicity by the activation level of LMP1 and NF-κB.

    Science.gov (United States)

    Zuo, Lielian; Yu, Haibo; Liu, Lingzhi; Tang, Yunlian; Wu, Hongzhuan; Yang, Jing; Zhu, Meijuan; Du, Shujuan; Zhao, Lian; Cao, Li; Li, Guiyuan; Lu, Jianhong

    2015-12-01

    A tumor model that Epstein-Barr virus (EBV) latent infection facilitated the tumorigenicity was previously established using the Maxi-EBV system. In the present approach, EBV-lost cell clones demonstrated significantly decreased tumorigenesis. On the other hand, the LMP1 gene in Maxi-EBV genome was replaced by that of nasopharyngeal carcinoma origin. The resultant cell line, 293-1/NL showed much lower malignancy than the original 293-EBV. The result was opposite to our expectation. The change of 293 sublineage cells for EBV harboring also got similar result. To seek the underlying reason, the copy number of EBV genome in all the cell lines was detected. The result indicated that 293-EBV contained about 4.5-fold higher EBV copies than 293-1/NL did. Parallel EBV genomes led to relatively stable copies in different 293 sublineages, suggesting the viral genome structure is a factor for the sustainability of EBV's copy number. Moreover, the LMP1 transcription in high copy-containing cells showed abnormally high level. Furthermore, the main LMP1-driven pathway, transcription factor NF-κB, was highly activated in high-copy cells. Here we first manifest by experimental model that the copy number of EBV latent genome correlates with the viral pathogenesis, which depends on the activation level of LMP1 and NF-κB. Overall, both the presence and amount of EBV genome are crucial for the viral oncogenicity.

  10. CODEX: a normalization and copy number variation detection method for whole exome sequencing.

    Science.gov (United States)

    Jiang, Yuchao; Oldridge, Derek A; Diskin, Sharon J; Zhang, Nancy R

    2015-03-31

    High-throughput sequencing of DNA coding regions has become a common way of assaying genomic variation in the study of human diseases. Copy number variation (CNV) is an important type of genomic variation, but detecting and characterizing CNV from exome sequencing is challenging due to the high level of biases and artifacts. We propose CODEX, a normalization and CNV calling procedure for whole exome sequencing data. The Poisson latent factor model in CODEX includes terms that specifically remove biases due to GC content, exon capture and amplification efficiency, and latent systemic artifacts. CODEX also includes a Poisson likelihood-based recursive segmentation procedure that explicitly models the count-based exome sequencing data. CODEX is compared to existing methods on a population analysis of HapMap samples from the 1000 Genomes Project, and shown to be more accurate on three microarray-based validation data sets. We further evaluate performance on 222 neuroblastoma samples with matched normals and focus on a well-studied rare somatic CNV within the ATRX gene. We show that the cross-sample normalization procedure of CODEX removes more noise than normalizing the tumor against the matched normal and that the segmentation procedure performs well in detecting CNVs with nested structures.

  11. Mitochondrial DNA copy number - but not a mitochondrial tandem CC to TT transition - is increased in sun-exposed skin.

    Science.gov (United States)

    Gebhard, Daniel; Mahler, Bettina; Matt, Katja; Burger, Katharina; Bergemann, Jörg

    2014-03-01

    Mitochondrial DNA (mtDNA) mutations are causatively associated with photo-ageing and are used as biomarkers of UV exposure. The most prominent mitochondrial mutation is the common deletion (CD), which is induced in many tissues by oxidative stress. More photo-specific mutations might be CC to TT tandem transitions which arise from UV-induced cyclobutane pyrimidine dimers. As nucleotide excision repair is absent in mitochondria, this DNA damage can presumably not be repaired resulting in high mitochondrial mutation levels. Here, we analysed levels of the CD, a mitochondrial and a chromosomal tandem transition in epidermis and dermis from exposed and less UV-exposed skin. We also analysed mtDNA copy number, for which changes as a result of oxidative stress have been described in different experimental settings. Whereas mitochondrial tandem transition levels were surprisingly low with no discernible correlation with UV exposure, mtDNA copy number and CD were significantly increased in UV-exposed samples.

  12. New cytogenetically visible copy number variant in region 8q21.2

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    Ewers Elisabeth

    2011-01-01

    Full Text Available Abstract Background Cytogenetically visible unbalanced chromosomal abnormalities (UBCA, reported for >50 euchromatic regions of almost all human autosomes, are comprised of a few megabases of DNA, and carriers are in many cases clinically healthy. It may be speculated, that some of the UBCA may be similar or identical to copy number variants (CNV of the human genome. Results Here we report on a yet unreported cytogenetically visible copy number variant (CNV in the long arm of chromosome 8, region 8q21.2, detected in three unrelated clinically healthy carriers. Conclusion The first description of a cytogenetically visible CNV/UBCA in 8q21.2 shows that banding cytogenetics is far from being outdated. It is a cost efficient, up-to-date method for a single cell specific overview on the whole genome, still prepared to deliver unexpected findings.

  13. Copy Number Variants Associated with 14 Cases of Self-Injurious Behavior.

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    Matthew D Shirley

    Full Text Available Copy number variants (CNVs were detected and analyzed in 14 probands with autism and intellectual disability with self-injurious behavior (SIB resulting in tissue damage. For each proband we obtained a clinical history and detailed behavioral descriptions. Genetic anomalies were observed in all probands, and likely clinical significance could be established in four cases. This included two cases having novel, de novo copy number variants and two cases having variants likely to have functional significance. These cases included segmental trisomy 14, segmental monosomy 21, and variants predicted to disrupt the function of ZEB2 (encoding a transcription factor and HTR2C (encoding a serotonin receptor. Our results identify variants in regions previously implicated in intellectual disability and suggest candidate genes that could contribute to the etiology of SIB.

  14. Model-integrated estimation of normal tissue contamination for cancer SNP allelic copy number data.

    Science.gov (United States)

    Stjernqvist, Susann; Rydén, Tobias; Greenman, Chris D

    2011-01-01

    SNP allelic copy number data provides intensity measurements for the two different alleles separately. We present a method that estimates the number of copies of each allele at each SNP position, using a continuous-index hidden Markov model. The method is especially suited for cancer data, since it includes the fraction of normal tissue contamination, often present when studying data from cancer tumors, into the model. The continuous-index structure takes into account the distances between the SNPs, and is thereby appropriate also when SNPs are unequally spaced. In a simulation study we show that the method performs favorably compared to previous methods even with as much as 70% normal contamination. We also provide results from applications to clinical data produced using the Affymetrix genome-wide SNP 6.0 platform.

  15. Copy number variants and genetic traits: closer to the resolution of phenotypic to genotypic variability.

    Science.gov (United States)

    Beckmann, Jacques S; Estivill, Xavier; Antonarakis, Stylianos E

    2007-08-01

    A considerable and unanticipated plasticity of the human genome, manifested as inter-individual copy number variation, has been discovered. These structural changes constitute a major source of inter-individual genetic variation that could explain variable penetrance of inherited (Mendelian and polygenic) diseases and variation in the phenotypic expression of aneuploidies and sporadic traits, and might represent a major factor in the aetiology of complex, multifactorial traits. For these reasons, an effort should be made to discover all common and rare copy number variants (CNVs) in the human population. This will also enable systematic exploration of both SNPs and CNVs in association studies to identify the genomic contributors to the common disorders and complex traits.

  16. ascatNgs: Identifying Somatically Acquired Copy-Number Alterations from Whole-Genome Sequencing Data.

    Science.gov (United States)

    Raine, Keiran M; Van Loo, Peter; Wedge, David C; Jones, David; Menzies, Andrew; Butler, Adam P; Teague, Jon W; Tarpey, Patrick; Nik-Zainal, Serena; Campbell, Peter J

    2016-12-08

    We have developed ascatNgs to aid researchers in carrying out Allele-Specific Copy number Analysis of Tumours (ASCAT). ASCAT is capable of detecting DNA copy number changes affecting a tumor genome when comparing to a matched normal sample. Additionally, the algorithm estimates the amount of tumor DNA in the sample, known as Aberrant Cell Fraction (ACF). ASCAT itself is an R-package which requires the generation of many file types. Here, we present a suite of tools to help handle this for the user. Our code is available on our GitHub site (https://github.com/cancerit). This unit describes both 'one-shot' execution and approaches more suitable for large-scale compute farms. © 2016 by John Wiley & Sons, Inc.

  17. A multi-megabase copy number gain causes maternal transmission ratio distortion on mouse chromosome 2.

    Directory of Open Access Journals (Sweden)

    John P Didion

    2015-02-01

    Full Text Available Significant departures from expected Mendelian inheritance ratios (transmission ratio distortion, TRD are frequently observed in both experimental crosses and natural populations. TRD on mouse Chromosome (Chr 2 has been reported in multiple experimental crosses, including the Collaborative Cross (CC. Among the eight CC founder inbred strains, we found that Chr 2 TRD was exclusive to females that were heterozygous for the WSB/EiJ allele within a 9.3 Mb region (Chr 2 76.9 - 86.2 Mb. A copy number gain of a 127 kb-long DNA segment (designated as responder to drive, R2d emerged as the strongest candidate for the causative allele. We mapped R2d sequences to two loci within the candidate interval. R2d1 is located near the proximal boundary, and contains a single copy of R2d in all strains tested. R2d2 maps to a 900 kb interval, and the number of R2d copies varies from zero in classical strains (including the mouse reference genome to more than 30 in wild-derived strains. Using real-time PCR assays for the copy number, we identified a mutation (R2d2WSBdel1 that eliminates the majority of the R2d2WSB copies without apparent alterations of the surrounding WSB/EiJ haplotype. In a three-generation pedigree segregating for R2d2WSBdel1, the mutation is transmitted to the progeny and Mendelian segregation is restored in females heterozygous for R2d2WSBdel1, thus providing direct evidence that the copy number gain is causal for maternal TRD. We found that transmission ratios in R2d2WSB heterozygous females vary between Mendelian segregation and complete distortion depending on the genetic background, and that TRD is under genetic control of unlinked distorter loci. Although the R2d2WSB transmission ratio was inversely correlated with average litter size, several independent lines of evidence support the contention that female meiotic drive is the cause of the distortion. We discuss the implications and potential applications of this novel meiotic drive system.

  18. A Multi-Megabase Copy Number Gain Causes Maternal Transmission Ratio Distortion on Mouse Chromosome 2

    Science.gov (United States)

    Didion, John P.; Morgan, Andrew P.; Clayshulte, Amelia M.-F.; Mcmullan, Rachel C.; Yadgary, Liran; Petkov, Petko M.; Bell, Timothy A.; Gatti, Daniel M.; Crowley, James J.; Hua, Kunjie; Aylor, David L.; Bai, Ling; Calaway, Mark; Chesler, Elissa J.; French, John E.; Geiger, Thomas R.; Gooch, Terry J.; Garland, Theodore; Harrill, Alison H.; Hunter, Kent; McMillan, Leonard; Holt, Matt; Miller, Darla R.; O'Brien, Deborah A.; Paigen, Kenneth; Pan, Wenqi; Rowe, Lucy B.; Shaw, Ginger D.; Simecek, Petr; Sullivan, Patrick F.; Svenson, Karen L; Weinstock, George M.; Threadgill, David W.; Pomp, Daniel; Churchill, Gary A.; Pardo-Manuel de Villena, Fernando

    2015-01-01

    Significant departures from expected Mendelian inheritance ratios (transmission ratio distortion, TRD) are frequently observed in both experimental crosses and natural populations. TRD on mouse Chromosome (Chr) 2 has been reported in multiple experimental crosses, including the Collaborative Cross (CC). Among the eight CC founder inbred strains, we found that Chr 2 TRD was exclusive to females that were heterozygous for the WSB/EiJ allele within a 9.3 Mb region (Chr 2 76.9 – 86.2 Mb). A copy number gain of a 127 kb-long DNA segment (designated as responder to drive, R2d) emerged as the strongest candidate for the causative allele. We mapped R2d sequences to two loci within the candidate interval. R2d1 is located near the proximal boundary, and contains a single copy of R2d in all strains tested. R2d2 maps to a 900 kb interval, and the number of R2d copies varies from zero in classical strains (including the mouse reference genome) to more than 30 in wild-derived strains. Using real-time PCR assays for the copy number, we identified a mutation (R2d2WSBdel1) that eliminates the majority of the R2d2WSB copies without apparent alterations of the surrounding WSB/EiJ haplotype. In a three-generation pedigree segregating for R2d2WSBdel1, the mutation is transmitted to the progeny and Mendelian segregation is restored in females heterozygous for R2d2WSBdel1, thus providing direct evidence that the copy number gain is causal for maternal TRD. We found that transmission ratios in R2d2WSB heterozygous females vary between Mendelian segregation and complete distortion depending on the genetic background, and that TRD is under genetic control of unlinked distorter loci. Although the R2d2WSB transmission ratio was inversely correlated with average litter size, several independent lines of evidence support the contention that female meiotic drive is the cause of the distortion. We discuss the implications and potential applications of this novel meiotic drive system. PMID

  19. Characterization of an inducible promoter in different DNA copy number conditions.

    Science.gov (United States)

    Zucca, Susanna; Pasotti, Lorenzo; Mazzini, Giuliano; De Angelis, Maria Gabriella Cusella; Magni, Paolo

    2012-03-28

    The bottom-up programming of living organisms to implement novel user-defined biological capabilities is one of the main goals of synthetic biology. Currently, a predominant problem connected with the construction of even simple synthetic biological systems is the unpredictability of the genetic circuitry when assembled and incorporated in living cells. Copy number, transcriptional/translational demand and toxicity of the DNA-encoded functions are some of the major factors which may lead to cell overburdening and thus to nonlinear effects on system output. It is important to disclose the linearity working boundaries of engineered biological systems when dealing with such phenomena. The output of an N-3-oxohexanoyl-L-homoserine lactone (HSL)-inducible RFP-expressing device was studied in Escherichia coli in different copy number contexts, ranging from 1 copy per cell (integrated in the genome) to hundreds (via multicopy plasmids). The system is composed by a luxR constitutive expression cassette and a RFP gene regulated by the luxI promoter, which is activated by the HSL-LuxR complex. System output, in terms of promoter activity as a function of HSL concentration, was assessed relative to the one of a reference promoter in identical conditions by using the Relative Promoter Units (RPU) approach. Nonlinear effects were observed in the maximum activity, which is identical in single and low copy conditions, while it decreases for higher copy number conditions. In order to properly compare the luxI promoter strength among all the conditions, a mathematical modeling approach was used to relate the promoter activity to the estimated HSL-LuxR complex concentration, which is the actual activator of transcription. During model fitting, a correlation between the copy number and the dissociation constant of HSL-LuxR complex and luxI promoter was observed. Even in a simple inducible system, nonlinear effects are observed and non-trivial data processing is necessary to fully

  20. Copy number expansion of the STX17 duplication in melanoma tissue from Grey horses

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    Sundström Elisabeth

    2012-08-01

    Full Text Available Abstract Background Greying with age in horses is an autosomal dominant trait, associated with loss of hair pigmentation, melanoma and vitiligo-like depigmentation. We recently identified a 4.6 kb duplication in STX17 to be associated with the phenotype. The aims of this study were to investigate if the duplication in Grey horses shows copy number variation and to exclude that any other polymorphism is uniquely associated with the Grey mutation. Results We found little evidence for copy number expansion of the duplicated sequence in blood DNA from Grey horses. In contrast, clear evidence for copy number expansions was indicated in five out of eight tested melanoma tissues or melanoma cell lines. A tendency of a higher copy number in aggressive tumours was also found. Massively parallel resequencing of the ~350 kb Grey haplotype did not reveal any additional mutations perfectly associated with the phenotype, confirming the duplication as the true causative mutation. We identified three SNP alleles that were present in a subset of Grey haplotypes within the 350 kb region that shows complete linkage disequilibrium with the causative mutation. Thus, these three nucleotide substitutions must have occurred subsequent to the duplication, consistent with our interpretation that the Grey mutation arose more than 2,000 years before present. Conclusions These results suggest that the mutation acts as a melanoma-driving regulatory element. The elucidation of the mechanistic features of the duplication will be of considerable interest for the characterization of these horse melanomas as well as for the field of human melanoma research.

  1. EPSPS Gene Copy Number and Whole-Plant Glyphosate Resistance Level in Kochia scoparia

    OpenAIRE

    Gaines, Todd A.; Barker, Abigail L.; Patterson, Eric L.; Westra, Philip; Westra, Eric P.; Wilson, Robert G.; Jha, Prashant; Kumar, Vipan; Andrew R Kniss

    2016-01-01

    Glyphosate-resistant (GR) Kochia scoparia has evolved in dryland chemical fallow systems throughout North America and the mechanism of resistance involves 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) gene duplication. Agricultural fields in four states were surveyed for K. scoparia in 2013 and tested for glyphosate-resistance level and EPSPS gene copy number. Glyphosate resistance was confirmed in K. scoparia populations collected from sugarbeet fields in Colorado, Wyoming, and Nebrask...

  2. DNA Copy Number Signature to Predict Recurrence in Early-Stage Ovarian Cancer

    Science.gov (United States)

    2015-08-01

    and clinical data inventory at MGH, 4) Sequenced RNA from these tumor samples. 2 Preliminary RNAseq analysis has indicated the need of analyzing...CNV on 300 samples, so that integration analysis with RNAseq can initiate. Plans for the next reporting period to accomplish the goals: Finish...analysis of DNA CNV on 300 samples and integrated analysis of the copy number variation result and the RNAseq results obtained from a paralleled DOD

  3. Critical evaluation of HPV16 gene copy number quantification by SYBR green PCR.

    Science.gov (United States)

    Roberts, Ian; Ng, Grace; Foster, Nicola; Stanley, Margaret; Herdman, Michael T; Pett, Mark R; Teschendorff, Andrew; Coleman, Nicholas

    2008-07-24

    Human papilloma virus (HPV) load and physical status are considered useful parameters for clinical evaluation of cervical squamous cell neoplasia. However, the errors implicit in HPV gene quantification by PCR are not well documented. We have undertaken the first rigorous evaluation of the errors that can be expected when using SYBR green qPCR for quantification of HPV type 16 gene copy numbers. We assessed a modified method, in which external calibration curves were generated from a single construct containing HPV16 E2, HPV16 E6 and the host gene hydroxymethylbilane synthase in a 1:1:1 ratio. When testing dilutions of mixed HPV/host DNA in replicate runs, we observed errors in quantifying E2 and E6 amplicons of 5-40%, with greatest error at the lowest DNA template concentration (3 ng/microl). Errors in determining viral copy numbers per diploid genome were 13-53%. Nevertheless, in cervical keratinocyte cell lines we observed reasonable agreement between viral loads determined by qPCR and Southern blotting. The mean E2/E6 ratio in episome-only cells was 1.04, but with a range of 0.76-1.32. In three integrant-only lines the mean E2/E6 ratios were 0.20, 0.72 and 2.61 (values confirmed by gene-specific Southern blotting). When E2/E6 ratios in fourteen HPV16-positive cervical carcinomas were analysed, conclusions regarding viral physical state could only be made in three cases, where the E2/E6 ratio was unavoidable inaccuracies that should be allowed for when quantifying HPV gene copy number. While E6 copy numbers can be considered to provide a useable indication of viral loads, the E2/E6 ratio is of limited value. Previous studies may have overestimated the frequency of mixed episomal/integrant HPV infections.

  4. De novo copy number variations in cloned dogs from the same nuclear donor

    OpenAIRE

    Jung, Seung-Hyun; Yim, Seon-Hee; Oh, Hyun Ju; Park, Jung Eun; Kim, Min Jung; Kim, Geon A; Kim, Tae-Min; Kim, Jin-Soo; Lee, Byeong Chun; Chung, Yeun-Jun

    2013-01-01

    Background Somatic mosaicism of copy number variants (CNVs) in human body organs and de novo CNV event in monozygotic twins suggest that de novo CNVs can occur during mitotic recombination. These de novo CNV events are important for understanding genetic background of evolution and diverse phenotypes. In this study, we explored de novo CNV event in cloned dogs with identical genetic background. Results We analyzed CNVs in seven cloned dogs using the nuclear donor genome as reference by array-...

  5. Simple binary segmentation frameworks for identifying variation in DNA copy number

    Directory of Open Access Journals (Sweden)

    Yang Tae Young

    2012-10-01

    Full Text Available Abstract Background Variation in DNA copy number, due to gains and losses of chromosome segments, is common. A first step for analyzing DNA copy number data is to identify amplified or deleted regions in individuals. To locate such regions, we propose a circular binary segmentation procedure, which is based on a sequence of nested hypothesis tests, each using the Bayesian information criterion. Results Our procedure is convenient for analyzing DNA copy number in two general situations: (1 when using data from multiple sources and (2 when using cohort analysis of multiple patients suffering from the same type of cancer. In the first case, data from multiple sources such as different platforms, labs, or preprocessing methods are used to study variation in copy number in the same individual. Combining these sources provides a higher resolution, which leads to a more detailed genome-wide survey of the individual. In this case, we provide a simple statistical framework to derive a consensus molecular signature. In the framework, the multiple sequences from various sources are integrated into a single sequence, and then the proposed segmentation procedure is applied to this sequence to detect aberrant regions. In the second case, cohort analysis of multiple patients is carried out to derive overall molecular signatures for the cohort. For this case, we provide another simple statistical framework in which data across multiple profiles is standardized before segmentation. The proposed segmentation procedure is then applied to the standardized profiles one at a time to detect aberrant regions. Any such regions that are common across two or more profiles are probably real and may play important roles in the cancer pathogenesis process. Conclusions The main advantages of the proposed procedure are flexibility and simplicity.

  6. Escherichia coli O157:H7 strains isolated from High-Event Period beef contamination have strong biofilm-forming ability and low sanitizer susceptibility, which are associated with high pO157 plasmid copy number

    Science.gov (United States)

    In the meat industry, a “High Event Period” (HEP) is defined as a time period when beef processing establishments experience an increased occurrence of product contamination by E. coli O157:H7. Our previous studies suggested that bacterial biofilm formation and sanitizer resistance might contribute...

  7. Genotyping Single Nucleotide Polymorphisms and Copy Number Variability of the FCGRs Expressed on NK Cells.

    Science.gov (United States)

    Erbe, Amy K; Wang, Wei; Gallenberger, Mikayla; Hank, Jacquelyn A; Sondel, Paul M

    2016-01-01

    Natural killer (NK) cells are one of the main effector immune cells involved in antibody-dependent cell-mediated cytotoxicity (ADCC). Upon recognition of cell-bound IgG antibodies, which occurs through Fc gamma receptors (FCGRs) expressed on the cell surface of NK cells, NK cells become activated and lyse target tumor or infected cells. The FCGRs, FCGR3A and FCGR2C, expressed on the surface of NK cells have single nucleotide polymorphisms (SNPs) that result in differential activity of NK cells. In addition to SNP genetic variation within each of these genes, the FCGRs are subject to copy number variation (CNV), which leads to variable protein expression levels on the cell surface. Studies have found that FCGR genotype for FCGR3A and FCGR2C is associated with variation in the response to immunotherapy.Due to high sequence homology within FCGR3 and FCGR2 families, there are difficulties associated with genotyping these specific receptors related to cross-amplification of non-targeted FCGRs. To improve specificity for both FCGR3A and FCGR2C, Rnase-H (RH) primers were designed to amplify specifically FCGR3A (while not co-amplifying FCGR3B) and FCGR2C (while not co-amplifying FCGR2B). In addition, fluorescently labeled locked nucleic acid (LNA) probes provide additional precision for determination of the SNPs within both FCGR3A and FCGR2C. For CNV determination, separate fluorescently labeled probes for FCGR3A, and for FCGR2C, can be used with the same RH primers for each gene. These probes can be combined in the same well with control primers/probe for a known diploid gene and used to calculate the copy number of both FCGR3A and FCGR2C. Here we provide new detailed methodology that allows for the specific amplification of these FCGRs in a single PCR reaction, allowing for genotyping of both the SNPs and CNVs using real-time PCR.

  8. Simple and versatile molecular method of copy-number measurement using cloned competitors.

    Science.gov (United States)

    Kim, Hyun-Kyoung; Hwang, Hai-Li; Park, Seong-Yeol; Lee, Kwang Man; Park, Won Cheol; Kim, Han-Seong; Um, Tae-Hyun; Hong, Young Jun; Lee, Jin Kyung; Joo, Sun-Young; Seoh, Ju-Young; Song, Yeong-Wook; Kim, Soo-Youl; Kim, Yong-Nyun; Hong, Kyeong-Man

    2013-01-01

    Variations and alterations of copy numbers (CNVs and CNAs) carry disease susceptibility and drug responsiveness implications. Although there are many molecular methods to measure copy numbers, sensitivity, reproducibility, cost, and time issues remain. In the present study, we were able to solve those problems utilizing our modified real competitive PCR method with cloned competitors (mrcPCR). First, the mrcPCR for ERBB2 copy number was established, and the results were comparable to current standard methods but with a shorter assay time and a lower cost. Second, the mrcPCR assays for 24 drug-target genes were established, and the results in a panel of NCI-60 cells were comparable to those from real-time PCR and microarray. Third, the mrcPCR results for FCGR3A and the FCGR3B CNVs were comparable to those by the paralog ratio test (PRT), but without PRT's limitations. These results suggest that mrcPCR is comparable to the currently available standard or the most sensitive methods. In addition, mrcPCR would be invaluable for measurement of CNVs in genes with variants of similar structures, because combination of the other methods is not necessary, along with its other advantages such as short assay time, small sample amount requirement, and applicability to all sequences and genes.

  9. Detection and validation of copy number variation in X-linked mental retardation.

    Science.gov (United States)

    Bauters, M; Weuts, A; Vandewalle, J; Nevelsteen, J; Marynen, P; Van Esch, H; Froyen, G

    2008-01-01

    Studies to identify the genetic defects associated with X-linked mental retardation (XLMR) in males have revealed tens of genes important for normal brain development and cognitive functioning in men. Despite extensive efforts in breakpoint cloning of chromosomal rearrangements and mutation screening of candidate genes on the X chromosome, still many XLMR families and sporadic cases remain unsolved. It is now clear that submicroscopic copy number changes on the X chromosome can explain about 5% of these idiopathic cases. Interestingly, beside gene deletions, an increase in gene dosage due to genomic duplications seems to contribute to causality more often than expected. Since larger duplications on the X chromosome are tolerated compared to deletions, they often harbour more than one gene hampering the identification of the causal gene. In contrast to copy number variations (CNVs) on autosomes, most disease-associated CNVs on the X chromosome in males are inherited from their mothers who normally do not present with any clinical symptoms due to non-random X inactivation. Here, we review the different methods applied to study copy number alterations on the X chromosome in patients with cognitive impairment, discuss those CNVs that are associated with disease and elaborate on the genes and mechanisms involved. At the end, we will resume in vivo assays to study the relation of CNVs on the X chromosome and mental disability.

  10. Tumor transcriptome sequencing reveals allelic expression imbalances associated with copy number alterations.

    Science.gov (United States)

    Tuch, Brian B; Laborde, Rebecca R; Xu, Xing; Gu, Jian; Chung, Christina B; Monighetti, Cinna K; Stanley, Sarah J; Olsen, Kerry D; Kasperbauer, Jan L; Moore, Eric J; Broomer, Adam J; Tan, Ruoying; Brzoska, Pius M; Muller, Matthew W; Siddiqui, Asim S; Asmann, Yan W; Sun, Yongming; Kuersten, Scott; Barker, Melissa A; De La Vega, Francisco M; Smith, David I

    2010-02-19

    Due to growing throughput and shrinking cost, massively parallel sequencing is rapidly becoming an attractive alternative to microarrays for the genome-wide study of gene expression and copy number alterations in primary tumors. The sequencing of transcripts (RNA-Seq) should offer several advantages over microarray-based methods, including the ability to detect somatic mutations and accurately measure allele-specific expression. To investigate these advantages we have applied a novel, strand-specific RNA-Seq method to tumors and matched normal tissue from three patients with oral squamous cell carcinomas. Additionally, to better understand the genomic determinants of the gene expression changes observed, we have sequenced the tumor and normal genomes of one of these patients. We demonstrate here that our RNA-Seq method accurately measures allelic imbalance and that measurement on the genome-wide scale yields novel insights into cancer etiology. As expected, the set of genes differentially expressed in the tumors is enriched for cell adhesion and differentiation functions, but, unexpectedly, the set of allelically imbalanced genes is also enriched for these same cancer-related functions. By comparing the transcriptomic perturbations observed in one patient to his underlying normal and tumor genomes, we find that allelic imbalance in the tumor is associated with copy number mutations and that copy number mutations are, in turn, strongly associated with changes in transcript abundance. These results support a model in which allele-specific deletions and duplications drive allele-specific changes in gene expression in the developing tumor.

  11. Simple and versatile molecular method of copy-number measurement using cloned competitors.

    Directory of Open Access Journals (Sweden)

    Hyun-Kyoung Kim

    Full Text Available Variations and alterations of copy numbers (CNVs and CNAs carry disease susceptibility and drug responsiveness implications. Although there are many molecular methods to measure copy numbers, sensitivity, reproducibility, cost, and time issues remain. In the present study, we were able to solve those problems utilizing our modified real competitive PCR method with cloned competitors (mrcPCR. First, the mrcPCR for ERBB2 copy number was established, and the results were comparable to current standard methods but with a shorter assay time and a lower cost. Second, the mrcPCR assays for 24 drug-target genes were established, and the results in a panel of NCI-60 cells were comparable to those from real-time PCR and microarray. Third, the mrcPCR results for FCGR3A and the FCGR3B CNVs were comparable to those by the paralog ratio test (PRT, but without PRT's limitations. These results suggest that mrcPCR is comparable to the currently available standard or the most sensitive methods. In addition, mrcPCR would be invaluable for measurement of CNVs in genes with variants of similar structures, because combination of the other methods is not necessary, along with its other advantages such as short assay time, small sample amount requirement, and applicability to all sequences and genes.

  12. Concomitant high gene copy number and protein overexpression of IGF1R and EGFR negatively affect disease-free survival of surgically resected non-small-cell-lung cancer patients

    Science.gov (United States)

    Flacco, A.; Bianconi, F.; Ragusa, M.; Vannucci, J.; Bellezza, G.; Chiari, R.; Minotti, V.; Pistola, L.; Tofanetti, F. R.; Siggillino, A.; Baldelli, E.; Sidoni, A.; Daddi, N.; Puma, F.; Varella-Garcia, M.; Crinò, L.

    2014-01-01

    Background Insulin-like growth factor 1 receptor (IGF1R) represents a novel molecular target in non-small-cell-lung cancer (NSCLC). IGF1R and epidermal growth factor receptor (EGFR) activation are essential to mediate tumor cell survival, proliferation, and invasion. This study investigates the prognostic role of IGF1R and EGFR in surgically resected NSCLC. Materials and methods IGF1R and EGFR copy number gain (CNG) were tested by fluorescence in situ hybridization (FISH) and protein expression by immunohistochemistry (IHC) in 125 stage I–II–IIIA NSCLC patients. Results Fourty-six tumors (40.3 %) were IGF1R FISH-positive (FISH+), and 76 (67.2 %) were EGFR FISH+. Tumors with concomitant IGF1R/EGFR FISH+ were observed in 34 cases (30.1 %). IGF1R and EGFR FISH+ were associated with SCC histology (p = 0.01 and p = 0.04, respectively). IGF1R and EGFR protein over-expression (IHC+) were detected in 45 (36.0 %) and 69 (55.2 %) cases, respectively. Tumors with concomitant IGF1R/EGFR IHC+ were detected in 31 (24.8 %) patients. IGF1R/EGFR FISH+ and IGF1R/EGFR IHC+ were significantly associated (χ2 = 4.02, p = 0.04). Patients with IGF1R/EGFR FISH+ and IGF1R/EGFR IHC+ were associated with shorter disease-free survival (DFS) (p = 0.05 and p = 0.05, respectively). Patients with concomitant IGF1R/EGFR FISH+/IHC+ had a worse DFS and overall survival (p = 0.005 and p = 0.01, respectively). The multivariate model confirmed that IGF1R/EGFR FISH+/IHC+ (hazard ratio (HR), 4.08; p = 0.01) and tumor stage (II–III vs I) (HR, 4.77; p = 0.003) were significantly associated with worse DFS. Conclusions IGF1R/EGFR FISH+ correlates with IGF1R/EGFR IHC+. IGF1R/EGFR FISH+/IHC+ is an independent negative prognostic factor for DFS in early NSCLC. These features may have important implications for future anti-IGF1R therapeutic approaches. PMID:23314677

  13. Significant heterogeneity in Wolbachia copy number within and between populations of Onchocerca volvulus.

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    Armoo, Samuel; Doyle, Stephen R; Osei-Atweneboana, Mike Y; Grant, Warwick N

    2017-04-18

    Wolbachia are intracellular bacteria found in arthropods and several filarial nematode species. The filarial Wolbachia have been proposed to be involved in the immunopathology associated with onchocerciasis. Higher Wolbachia-to-nematode ratios have been reported in the savannah-ecotype compared to the forest-ecotype, and have been interpreted as consistent with a correlation between Wolbachia density and disease severity. However, factors such as geographic stratification and ivermectin drug exposure can lead to significant genetic heterogeneity in the nematode host populations, so we investigated whether Wolbachia copy number variation is also associated with these underlying factors. Genomic DNA was prepared from single adult nematodes representing forest and savannah ecotypes sampled from Togo, Ghana, Côte d'Ivoire and Mali. A qPCR assay was developed to measure the number of Wolbachia genome(s) per nematode genome. Next-generation sequencing (NGS) was also used to measure relative Wolbachia copy number, and independently verify the qPCR assay. Significant variation was observed within the forest (range: 0.02 to 452.99; median: 10.58) and savannah (range: 0.01 to 1106.25; median: 9.10) ecotypes, however, no significant difference between ecotypes (P = 0.645) was observed; rather, strongly significant Wolbachia variation was observed within and between the nine study communities analysed (P = 0.021), independent of ecotype. Analysis of ivermectin-treated and untreated nematodes by qPCR showed no correlation (P = 0.869); however, an additional analysis of a subset of the nematodes by qPCR and NGS revealed a correlation between response to ivermectin treatment and Wolbachia copy number (P = 0.020). This study demonstrates that extensive within and between population variation exists in the Wolbachia content of individual adult O. volvulus. The origin and functional significance of such variation (up to ~ 100,000-fold between worms; ~10 to 100

  14. Formation of chimeric genes by copy-number variation as a mutational mechanism in schizophrenia.

    Science.gov (United States)

    Rippey, Caitlin; Walsh, Tom; Gulsuner, Suleyman; Brodsky, Matt; Nord, Alex S; Gasperini, Molly; Pierce, Sarah; Spurrell, Cailyn; Coe, Bradley P; Krumm, Niklas; Lee, Ming K; Sebat, Jonathan; McClellan, Jon M; King, Mary-Claire

    2013-10-03

    Chimeric genes can be caused by structural genomic rearrangements that fuse together portions of two different genes to create a novel gene. We hypothesize that brain-expressed chimeras may contribute to schizophrenia. Individuals with schizophrenia and control individuals were screened genome wide for copy-number variants (CNVs) that disrupted two genes on the same DNA strand. Candidate events were filtered for predicted brain expression and for frequency genes in localization, regulation, or function. Subcellular localizations of DNAJA2-NETO2 and MAP3K3-DDX42 differed from their parent genes. On the basis of the expression profile of the MATK promoter, MATK-ZFR2 is likely to be far more highly expressed in the brain during development than the ZFR2 parent gene. MATK-ZFR2 includes a ZFR2-derived isoform that we demonstrate localizes preferentially to neuronal dendritic branch sites. These results suggest that the formation of chimeric genes is a mechanism by which CNVs contribute to schizophrenia and that, by interfering with parent gene function, chimeras may disrupt critical brain processes, including neurogenesis, neuronal differentiation, and dendritic arborization.

  15. FOXL2 copy number changes in the molecular pathogenesis of BPES: unique cohort of 17 deletions.

    Science.gov (United States)

    D'haene, B; Nevado, J; Pugeat, M; Pierquin, G; Lowry, R B; Reardon, W; Delicado, A; García-Miñaur, S; Palomares, M; Courtens, W; Stefanova, M; Wallace, S; Watkins, W; Shelling, A N; Wieczorek, D; Veitia, R A; De Paepe, A; Lapunzina, P; De Baere, E

    2010-05-01

    Blepharophimosis Syndrome (BPES) is an autosomal dominant developmental disorder of the eyelids with or without ovarian dysfunction caused by FOXL2 mutations. Overall, FOXL2deletions represent 12% of all genetic defects in BPES. Here, we have identified and characterized 16 new and one known FOXL2 deletion combining multiplex ligation-dependent probe amplification (MLPA), custom-made quantitative PCR (qPCR) and/or microarray-based copy number screening. The deletion breakpoints could be localized for 13 out of 17 deletions. The deletion size is highly variable (29.8 kb - 11.5 Mb), indicating absence of a recombination hotspot. Although the heterogeneity of their size and breakpoints is not reflected in the uniform BPES phenotype, there is considerable phenotypic variability regarding associated clinical findings including psychomotor retardation (8/17), microcephaly (6/17), and subtle skeletal features (2/17). In addition, in all females in whom ovarian function could be assessed, FOXL2 deletions proved to be associated with variable degrees of ovarian dysfunction. In conclusion, we present the largest series of BPES patients with FOXL2 deletions and standardized phenotyping reported so far. Our genotype-phenotype data can be useful for providing a prognosis (i.e. occurrence of associated features) in newborns with BPES carrying a FOXL2 deletion.

  16. Mutation dependance of the mitochondrial DNA copy number in the first stages of human embryogenesis.

    Science.gov (United States)

    Monnot, Sophie; Samuels, David C; Hesters, Laetitia; Frydman, Nelly; Gigarel, Nadine; Burlet, Philippe; Kerbrat, Violaine; Lamazou, Frédéric; Frydman, René; Benachi, Alexandra; Feingold, Josué; Rotig, Agnes; Munnich, Arnold; Bonnefont, Jean-Paul; Steffann, Julie

    2013-05-01

    Mitochondrial DNA (mtDNA) content is thought to remain stable over the preimplantation period of human embryogenesis that is, therefore, suggested to be entirely dependent on ooplasm mtDNA capital. We have explored the impact of two disease-causing mutations [m.3243A>G myopathy, encephalopathy, lactic acidosis and stroke-like syndrome (MELAS) and m.8344A>G myoclonic epilepsy associated with ragged-red fibers (MERRF)] on mtDNA amounts in human oocytes and day 4-5 preimplantation embryos. The mtDNA amount was stable in MERRF and control materials, whereas gradually increasing from the germinal vesicle of oogenesis to the blastocyst stage of embryogenesis in MELAS cells, MELAS embryos carrying ∼3-fold higher mtDNA amount than control embryos (P = 0.0003). A correlation between mtDNA copy numbers and mutant loads was observed in MELAS embryos (R(2) = 0.42, P < 0.0013), suggestive of a compensation for the respiratory chain defect resulting from high mutation levels. These results suggest that mtDNA can replicate in early embryos and emphasize the need for sufficient amount of wild-type mtDNA to sustain embryonic development in humans.

  17. Copy Number Variation of UGT 2B Genes in Indian Families Using Whole Genome Scans

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    Avinash M. Veerappa

    2016-01-01

    Full Text Available Background and Objectives. Uridine diphospho-glucuronosyltransferase 2B (UGT2B is a family of genes involved in metabolizing steroid hormones and several other xenobiotics. These UGT2B genes are highly polymorphic in nature and have distinct polymorphisms associated with specific regions around the globe. Copy number variations (CNVs status of UGT2B17 in Indian population is not known and their disease associations have been inconclusive. It was therefore of interest to investigate the CNV profile of UGT2B genes. Methods. We investigated the presence of CNVs in UGT2B genes in 31 members from eight Indian families using Affymetrix Genome-Wide Human SNP Array 6.0 chip. Results. Our data revealed >50% of the study members carried CNVs in UGT2B genes, of which 76% showed deletion polymorphism. CNVs were observed more in UGT2B17 (76.4% than in UGT2B15 (17.6%. Molecular network and pathway analysis found enrichment related to steroid metabolic process, carboxylesterase activity, and sequence specific DNA binding. Interpretation and Conclusion. We report the presence of UGT2B gene deletion and duplication polymorphisms in Indian families. Network analysis indicates the substitutive role of other possible genes in the UGT activity. The CNVs of UGT2B genes are very common in individuals indicating that the effect is neutral in causing any suspected diseases.

  18. Distribution and Functionality of Copy Number Variation across European Cattle Populations

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    Maulik Upadhyay

    2017-08-01

    Full Text Available Copy number variation (CNV, which is characterized by large-scale losses or gains of DNA fragments, contributes significantly to genetic and phenotypic variation. Assessing CNV across different European cattle populations might reveal genetic changes responsible for phenotypic differences, which have accumulated throughout the domestication history of cattle as consequences of evolutionary forces that act upon them. To explore pattern of CNVs across European cattle, we genotyped 149 individuals, that represent different European regions, using the Illumina Bovine HD Genotyping array. A total of 9,944 autosomal CNVs were identified in 149 samples using a Hidden Markov Model (HMM as employed in PennCNV. Animals originating from several breeds of British Isles, and Balkan and Italian regions, on average, displayed higher abundance of CNV counts than Dutch or Alpine animals. A total of 923 CNV regions (CNVRs were identified by aggregating CNVs overlapping in at least two animals. The hierarchical clustering of CNVRs indicated low differentiation and sharing of high-frequency CNVRs between European cattle populations. Various CNVRs identified in the present study overlapped with olfactory receptor genes and genes related to immune system. In addition, we also detected a CNV overlapping the Kit gene in English longhorn cattle which has previously been associated with color-sidedness. To conclude, we provide a comprehensive overview of CNV distribution in genome of European cattle. Our results indicate an important role of purifying selection and genomic drift in shaping CNV diversity that exists between different European cattle populations.

  19. Rapid detection of chromosome 18 copy number in buccal smears using DNA probes and FISH

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    Harris, C.; Nunez, M. [Univ. of Wisconsin, WI (United States); Giraldez, R. [ONCOR, Inc., Gaithersburg, MD (United States)

    1994-09-01

    Rapid diagnosis of trisomy 18 in newborns is often critical to clinical management decisions that must be made in a minimum of time. DNA probes combined with FISH can be used to accurately to determine the copy number of chromosome 18 in interphase cells. We have used the D18Z1 alpha satellite DNA probe to determine signal frequency in normal, previously karyotyped subjects, 12 females and 6 males. We also present one clinical case of trisomy 18, confirmed by karyotype, for comparison to the results obtained from normal subjects. Buccal smears, unlike cytogenetic preparations from peripheral blood, are quite resistant to penetration of probes and detection reagents resulting in higher levels of false monosomy. We have studied 19 individuals and have obtained consistent FISH results, ranging from 64 to 90% disomy. False monosomy rates ranged from 10 to 36%, while false trisomy or tetrasomy was less than 1% in all samples. High rates of false monosomy make this test questionable for detection of low order mosaicism for monosomy, but the extremely low false hyperploidy rate suggests that this is a dependable procedure for detection of trisomy 18, enabling the use of buccal epithelium which can be collected easily from even premature and tiny infants.

  20. Comparative oncogenomic analysis of copy number alterations in human and zebrafish tumors enables cancer driver discovery.

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    GuangJun Zhang

    2013-08-01

    Full Text Available The identification of cancer drivers is a major goal of current cancer research. Finding driver genes within large chromosomal events is especially challenging because such alterations encompass many genes. Previously, we demonstrated that zebrafish malignant peripheral nerve sheath tumors (MPNSTs are highly aneuploid, much like human tumors. In this study, we examined 147 zebrafish MPNSTs by massively parallel sequencing and identified both large and focal copy number alterations (CNAs. Given the low degree of conserved synteny between fish and mammals, we reasoned that comparative analyses of CNAs from fish versus human MPNSTs would enable elimination of a large proportion of passenger mutations, especially on large CNAs. We established a list of orthologous genes between human and zebrafish, which includes approximately two-thirds of human protein-coding genes. For the subset of these genes found in human MPNST CNAs, only one quarter of their orthologues were co-gained or co-lost in zebrafish, dramatically narrowing the list of candidate cancer drivers for both focal and large CNAs. We conclude that zebrafish-human comparative analysis represents a powerful, and broadly applicable, tool to enrich for evolutionarily conserved cancer drivers.

  1. [Copy number alterations in adult patients with mature B acute lymphoblastic leukemia treated with specific immunochemotherapy].

    Science.gov (United States)

    Ribera, Jordi; Zamora, Lurdes; García, Olga; Hernández-Rivas, Jesús-María; Genescà, Eulàlia; Ribera, Josep-Maria

    2016-12-02

    Unlike Burkitt lymphoma, molecular abnormalities other than C-MYC rearrangements have scarcely been studied in patients with mature B acute lymphoblastic leukemia (B-ALL). The aim of this study was to analyze the frequency and prognostic significance of copy number alterations (CNA) in genes involved in lymphoid differentiation, cell cycle and tumor suppression in adult patients with B-ALL. We have analyzed by multiplex ligation-dependent probe amplification the genetic material from bone marrow at diagnosis from 25 adult B-ALL patients treated with rituximab and specific chemotherapy. The most frequent CNA were alterations in the 14q32.33 region (11 cases, 44%) followed by alterations in the cell cycle regulator genes CDKN2A/B and RB1 (16%). No correlation between the presence of specific CNA and the clinical-biologic features or the response to therapy was found. The high frequency of CNA in the 14q32.33 region, CDKN2A/B and RB1 found in our study could contribute to the aggressiveness and invasiveness of mature B-ALL. Copyright © 2016 Elsevier España, S.L.U. All rights reserved.

  2. Functional Impact of Global Rare Copy Number Variation in Autism Spectrum Disorder

    Science.gov (United States)

    Pinto, Dalila; Pagnamenta, Alistair T.; Klei, Lambertus; Anney, Richard; Merico, Daniele; Regan, Regina; Conroy, Judith; Magalhaes, Tiago R.; Correia, Catarina; Abrahams, Brett S.; Almeida, Joana; Bacchelli, Elena; Bader, Gary D.; Bailey, Anthony J.; Baird, Gillian; Battaglia, Agatino; Berney, Tom; Bolshakova, Nadia; Bölte, Sven; Bolton, Patrick F.; Bourgeron, Thomas; Brennan, Sean; Brian, Jessica; Bryson, Susan E.; Carson, Andrew R.; Casallo, Guillermo; Casey, Jillian; Cochrane, Lynne; Corsello, Christina; Crawford, Emily L.; Crossett, Andrew; Dawson, Geraldine; de Jonge, Maretha; Delorme, Richard; Drmic, Irene; Duketis, Eftichia; Duque, Frederico; Estes, Annette; Farrar, Penny; Fernandez, Bridget A.; Filipa, Ana; Folstein, Susan E.; Fombonne, Eric; Freitag, Christine M.; Gilbert, John; Gillberg, Christopher; Glessner, Joseph T.; Goldberg, Jeremy; Green, Andrew; Green, Jonathan; Guter, Stephen J.; Hakonarson, Hakon; Heron, Elizabeth A.; Hill, Matthew; Holt, Richard; Howe, Jennifer L.; Hughes, Gillian; Hus, Vanessa; Igliozzi, Roberta; Kim, Cecilia; Klauck, Sabine M.; Kolevzon, Alexander; Korvatska, Olena; Kustanovich, Vlad; Lajonchere, Clara M.; Lamb, Janine A.; Laskawiec, Magdalena; Leboyer, Marion; Le Couteur, Ann; Leventhal, Bennett L.; Lionel, Anath C.; Liu, Xiao-Qing; Lord, Catherine; Lotspeich, Linda; Lund, Sabata C.; Maestrini, Elena; Mahoney, William; Mantoulan, Carine; Marshall, Christian R.; McConachie, Helen; McDougle, Christopher J.; McGrath, Jane; McMahon, William M.; Merikangas, Alison; Migita, Ohsuke; Minshew, Nancy J.; Mirza, Ghazala K.; Munson, Jeff; Nelson, Stanley F.; Noakes, Carolyn; Noor, Abdul; Nygren, Gudrun; Oliveira, Guiomar; Papanikolaou, Katerina; Parr, Jeremy R.; Parrini, Barbara; Paton, Tara; Pickles, Andrew; Pilorge, Marion; Piven, Joseph; Ponting, Chris P.; Posey, David J.; Poustka, Annemarie; Poustka, Fritz; Prasad, Aparna; Ragoussis, Jiannis; Renshaw, Katy; Rickaby, Jessica; Roberts, Wendy; Roeder, Kathryn; Roge, Bernadette; Rutter, Michael L.; Bierut, Laura J.; Rice, John P.; Consortium, SAGE; Salt, Jeff; Sansom, Katherine; Sato, Daisuke; Segurado, Ricardo; Senman, Lili; Shah, Naisha; Sheffield, Val C.; Soorya, Latha; Sousa, Inês; Stein, Olaf; Stoppioni, Vera; Strawbridge, Christina; Tancredi, Raffaella; Tansey, Katherine; Thiruvahindrapduram, Bhooma; Thompson, Ann P.; Thomson, Susanne; Tryfon, Ana; Tsiantis, John; Van Engeland, Herman; Vincent, John B.; Volkmar, Fred; Wallace, Simon; Wang, Kai; Wang, Zhouzhi; Wassink, Thomas H.; Webber, Caleb; Wing, Kirsty; Wittemeyer, Kerstin; Wood, Shawn; Wu, Jing; Yaspan, Brian L.; Zurawiecki, Danielle; Zwaigenbaum, Lonnie; Buxbaum, Joseph D.; Cantor, Rita M.; Cook, Edwin H.; Coon, Hilary; Cuccaro, Michael L.; Devlin, Bernie; Ennis, Sean; Gallagher, Louise; Geschwind, Daniel H.; Gill, Michael; Haines, Jonathan L.; Hallmayer, Joachim; Miller, Judith; Monaco, Anthony P.; Nurnberger, John I.; Paterson, Andrew D.; Pericak-Vance, Margaret A.; Schellenberg, Gerard D.; Szatmari, Peter; Vicente, Astrid M.; Vieland, Veronica J.; Wijsman, Ellen M.; Scherer, Stephen W.; Sutcliffe, James S.; Betancur, Catalina

    2010-01-01

    The autism spectrum disorders (ASDs) are a group of conditions characterized by impairments in reciprocal social interaction and communication, and the presence of restricted and repetitive behaviors1. Individuals with an ASD vary greatly in cognitive development, which can range from above average to intellectual disability (ID)2. While ASDs are known to be highly heritable (~90%)3, the underlying genetic determinants are still largely unknown. Here, we analyzed the genome-wide characteristics of rare (<1% frequency) copy number variation (CNV) in ASD using dense genotyping arrays. When comparing 996 ASD individuals of European ancestry to 1,287 matched controls, cases were found to carry a higher global burden of rare, genic CNVs (1.19 fold, P= 0.012), especially so for loci previously implicated in either ASD and/or intellectual disability (1.69 fold, P= 3.4×10−4). Among the CNVs, there were numerous de novo and inherited events, sometimes in combination in a given family, implicating many novel ASD genes like SHANK2, SYNGAP1, DLGAP2 and the X-linked DDX53-PTCHD1 locus. We also discovered an enrichment of CNVs disrupting functional gene-sets involved in cellular proliferation, projection and motility, and GTPase/Ras signaling. Our results reveal many new genetic and functional targets in ASD that may lead to final connected pathways. PMID:20531469

  3. Prospective diagnostic analysis of copy number variants using SNP microarrays in individuals with autism spectrum disorders.

    Science.gov (United States)

    Nava, Caroline; Keren, Boris; Mignot, Cyril; Rastetter, Agnès; Chantot-Bastaraud, Sandra; Faudet, Anne; Fonteneau, Eric; Amiet, Claire; Laurent, Claudine; Jacquette, Aurélia; Whalen, Sandra; Afenjar, Alexandra; Périsse, Didier; Doummar, Diane; Dorison, Nathalie; Leboyer, Marion; Siffroi, Jean-Pierre; Cohen, David; Brice, Alexis; Héron, Delphine; Depienne, Christel

    2014-01-01

    Copy number variants (CNVs) have repeatedly been found to cause or predispose to autism spectrum disorders (ASDs). For diagnostic purposes, we screened 194 individuals with ASDs for CNVs using Illumina SNP arrays. In several probands, we also analyzed candidate genes located in inherited deletions to unmask autosomal recessive variants. Three CNVs, a de novo triplication of chromosome 15q11-q12 of paternal origin, a deletion on chromosome 9p24 and a de novo 3q29 deletion, were identified as the cause of the disorder in one individual each. An autosomal recessive cause was considered possible in two patients: a homozygous 1p31.1 deletion encompassing PTGER3 and a deletion of the entire DOCK10 gene associated with a rare hemizygous missense variant. We also identified multiple private or recurrent CNVs, the majority of which were inherited from asymptomatic parents. Although highly penetrant CNVs or variants inherited in an autosomal recessive manner were detected in rare cases, our results mainly support the hypothesis that most CNVs contribute to ASDs in association with other CNVs or point variants located elsewhere in the genome. Identification of these genetic interactions in individuals with ASDs constitutes a formidable challenge.

  4. Copy number variation detection in whole-genome sequencing data using the Bayesian information criterion.

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    Xi, Ruibin; Hadjipanayis, Angela G; Luquette, Lovelace J; Kim, Tae-Min; Lee, Eunjung; Zhang, Jianhua; Johnson, Mark D; Muzny, Donna M; Wheeler, David A; Gibbs, Richard A; Kucherlapati, Raju; Park, Peter J

    2011-11-15

    DNA copy number variations (CNVs) play an important role in the pathogenesis and progression of cancer and confer susceptibility to a variety of human disorders. Array comparative genomic hybridization has been used widely to identify CNVs genome wide, but the next-generation sequencing technology provides an opportunity to characterize CNVs genome wide with unprecedented resolution. In this study, we developed an algorithm to detect CNVs from whole-genome sequencing data and applied it to a newly sequenced glioblastoma genome with a matched control. This read-depth algorithm, called BIC-seq, can accurately and efficiently identify CNVs via minimizing the Bayesian information criterion. Using BIC-seq, we identified hundreds of CNVs as small as 40 bp in the cancer genome sequenced at 10× coverage, whereas we could only detect large CNVs (> 15 kb) in the array comparative genomic hybridization profiles for the same genome. Eighty percent (14/16) of the small variants tested (110 bp to 14 kb) were experimentally validated by quantitative PCR, demonstrating high sensitivity and true positive rate of the algorithm. We also extended the algorithm to detect recurrent CNVs in multiple samples as well as deriving error bars for breakpoints using a Gibbs sampling approach. We propose this statistical approach as a principled yet practical and efficient method to estimate CNVs in whole-genome sequencing data.

  5. The genomic architecture of segmental duplications and associated copy number variants in dogs.

    Science.gov (United States)

    Nicholas, Thomas J; Cheng, Ze; Ventura, Mario; Mealey, Katrina; Eichler, Evan E; Akey, Joshua M

    2009-03-01

    Structural variation is an important and abundant source of genetic and phenotypic variation. Here we describe the first systematic and genome-wide analysis of segmental duplications and associated copy number variants (CNVs) in the modern domesticated dog, Canis familiaris, which exhibits considerable morphological, physiological, and behavioral variation. Through computational analyses of the publicly available canine reference sequence, we estimate that segmental duplications comprise approximately 4.21% of the canine genome. Segmental duplications overlap 841 genes and are significantly enriched for specific biological functions such as immunity and defense and KRAB box transcription factors. We designed high-density tiling arrays spanning all predicted segmental duplications and performed aCGH in a panel of 17 breeds and a gray wolf. In total, we identified 3583 CNVs, approximately 68% of which were found in two or more samples that map to 678 unique regions. CNVs span 429 genes that are involved in a wide variety of biological processes such as olfaction, immunity, and gene regulation. Our results provide insight into mechanisms of canine genome evolution and generate a valuable resource for future evolutionary and phenotypic studies.

  6. Novel Somatic Copy Number Alteration Identified for Cervical Cancer in the Mexican American Population

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    Alireza Torabi

    2016-08-01

    Full Text Available Cervical cancer affects millions of Americans, but the rate for cervical cancer in the Mexican American is approximately twice that for non-Mexican Americans. The etiologies of cervical cancer are still not fully understood. A number of somatic mutations, including several copy number alterations (CNAs, have been identified in the pathogenesis of cervical carcinomas in non-Mexican Americans. Thus, the purpose of this study was to investigate CNAs in association with cervical cancer in the Mexican American population. We conducted a pilot study of genome-wide CNA analysis using 2.5 million markers in four diagnostic groups: reference (n = 125, low grade dysplasia (cervical intraepithelial neoplasia (CIN-I, n = 4, high grade dysplasia (CIN-II and -III, n = 5 and invasive carcinoma (squamous cell carcinoma (SCC, n = 5 followed by data analyses using Partek. We observed a statistically-significant difference of CNA burden between case and reference groups of different sizes (>100 kb, 10–100 kb and 1–10 kb of CNAs that included deletions and amplifications, e.g., a statistically-significant difference of >100 kb deletions was observed between the reference (6.6% and pre-cancer and cancer (91.3% groups. Recurrent aberrations of 98 CNA regions were also identified in cases only. However, none of the CNAs have an impact on cancer progression. A total of 32 CNA regions identified contained tumor suppressor genes and oncogenes. Moreover, the pathway analysis revealed endometrial cancer and estrogen signaling pathways associated with this cancer (p < 0.05 using Kyoto Encyclopedia of Genes and Genomes (KEGG. This is the first report of CNAs identified for cervical cancer in the U.S. Latino population using high density markers. We are aware of the small sample size in the study. Thus, additional studies with a larger sample are needed to confirm the current findings.

  7. Phenotypic consequences of copy number variation: insights from Smith-Magenis and Potocki-Lupski syndrome mouse models.

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    Guénola Ricard

    Full Text Available A large fraction of genome variation between individuals is comprised of submicroscopic copy number variation of genomic DNA segments. We assessed the relative contribution of structural changes and gene dosage alterations on phenotypic outcomes with mouse models of Smith-Magenis and Potocki-Lupski syndromes. We phenotyped mice with 1n (Deletion/+, 2n (+/+, 3n (Duplication/+, and balanced 2n compound heterozygous (Deletion/Duplication copies of the same region. Parallel to the observations made in humans, such variation in gene copy number was sufficient to generate phenotypic consequences: in a number of cases diametrically opposing phenotypes were associated with gain versus loss of gene content. Surprisingly, some neurobehavioral traits were not rescued by restoration of the normal gene copy number. Transcriptome profiling showed that a highly significant propensity of transcriptional changes map to the engineered interval in the five assessed tissues. A statistically significant overrepresentation of the genes mapping to the entire length of the engineered chromosome was also found in the top-ranked differentially expressed genes in the mice containing rearranged chromosomes, regardless of the nature of the rearrangement, an observation robust across different cell lineages of the central nervous system. Our data indicate that a structural change at a given position of the human genome may affect not only locus and adjacent gene expression but also "genome regulation." Furthermore, structural change can cause the same perturbation in particular pathways regardless of gene dosage. Thus, the presence of a genomic structural change, as well as gene dosage imbalance, contributes to the ultimate phenotype.

  8. Phenotypic consequences of copy number variation: insights from Smith-Magenis and Potocki-Lupski syndrome mouse models.

    Science.gov (United States)

    Ricard, Guénola; Molina, Jessica; Chrast, Jacqueline; Gu, Wenli; Gheldof, Nele; Pradervand, Sylvain; Schütz, Frédéric; Young, Juan I; Lupski, James R; Reymond, Alexandre; Walz, Katherina

    2010-11-23

    A large fraction of genome variation between individuals is comprised of submicroscopic copy number variation of genomic DNA segments. We assessed the relative contribution of structural changes and gene dosage alterations on phenotypic outcomes with mouse models of Smith-Magenis and Potocki-Lupski syndromes. We phenotyped mice with 1n (Deletion/+), 2n (+/+), 3n (Duplication/+), and balanced 2n compound heterozygous (Deletion/Duplication) copies of the same region. Parallel to the observations made in humans, such variation in gene copy number was sufficient to generate phenotypic consequences: in a number of cases diametrically opposing phenotypes were associated with gain versus loss of gene content. Surprisingly, some neurobehavioral traits were not rescued by restoration of the normal gene copy number. Transcriptome profiling showed that a highly significant propensity of transcriptional changes map to the engineered interval in the five assessed tissues. A statistically significant overrepresentation of the genes mapping to the entire length of the engineered chromosome was also found in the top-ranked differentially expressed genes in the mice containing rearranged chromosomes, regardless of the nature of the rearrangement, an observation robust across different cell lineages of the central nervous system. Our data indicate that a structural change at a given position of the human genome may affect not only locus and adjacent gene expression but also "genome regulation." Furthermore, structural change can cause the same perturbation in particular pathways regardless of gene dosage. Thus, the presence of a genomic structural change, as well as gene dosage imbalance, contributes to the ultimate phenotype.

  9. A low-copy-number plasmid for retrieval of toxic genes from BACs and generation of conditional targeting constructs.

    Science.gov (United States)

    Na, Giyoun; Wolfe, Andrew; Ko, Chemyong; Youn, Hyesook; Lee, Young-Min; Byun, Sung June; Jeon, Iksoo; Koo, Yongbum

    2013-06-01

    Bacterial Artificial Chromosome (BAC) clones are widely used for retrieving genomic DNA sequences for gene targeting. In this study, low-copy-number plasmids pBAC-FB, pBAC-FC, and pBAC-DE, which carry the F plasmid replicon, were generated from pBACe3.6. pBAC-FB was successfully used to retrieve a sequence of a BAC that was resistant to retrieval by a high-copy-number plasmid via λ Red-mediated recombineering (gap-repair cloning). This plasmid was also used to retrieve two other genes from BAC, indicating its general usability retrieving genes from BAC. The retrieved genes were manipulated in generating targeting vectors for gene knockouts by recombineering. The functionality of the targeting vector was further validated in a targeting experiment with C57BL/6 embryonic stem cells. The low-copy-number plasmid pBAC-FB is a plasmid of choice to retrieve toxic DNA sequences from BACs and to manipulate them to generate gene-targeting constructs by recombineering.

  10. Adaptation of the Osmotolerant Yeast Zygosaccharomyces rouxii to an Osmotic Environment Through Copy Number Amplification of FLO11D

    Science.gov (United States)

    Watanabe, Jun; Uehara, Kenji; Mogi, Yoshinobu

    2013-01-01

    Copy number variations (CNVs) contribute to the adaptation process in two possible ways. First, they may have a direct role, in which a certain number of copies often provide a selective advantage. Second, CNVs can also indirectly contribute to adaptation because a higher copy number increases the so-called “mutational target size.” In this study, we show that the copy number amplification of FLO11D in the osmotolerant yeast Zygosaccharomyces rouxii promotes its further adaptation to a flor-formative environment, such as osmostress static culture conditions. We demonstrate that a gene, which was identified as FLO11D, is responsible for flor formation and that its expression is induced by osmostress under glucose-free conditions, which confer unique characteristics to Z. rouxii, such as osmostress-dependent flor formation. This organism possesses zero to three copies of FLO11D, and it appears likely that the FLO11D copy number increased in a branch of the Z. rouxii tree. The cellular hydrophobicity correlates with the FLO11D copy number, and the strain with a higher copy number of FLO11D exhibits a fitness advantage compared to a reference strain under osmostress static culture conditions. Our data indicate that the FLO gene-related system in Z. rouxii has evolved remarkably to adapt to osmostress environments. PMID:23893487

  11. Copy number variation is a fundamental aspect of the placental genome.

    Science.gov (United States)

    Hannibal, Roberta L; Chuong, Edward B; Rivera-Mulia, Juan Carlos; Gilbert, David M; Valouev, Anton; Baker, Julie C

    2014-05-01

    Discovery of lineage-specific somatic copy number variation (CNV) in mammals has led to debate over whether CNVs are mutations that propagate disease or whether they are a normal, and even essential, aspect of cell biology. We show that 1,000 N polyploid trophoblast giant cells (TGCs) of the mouse placenta contain 47 regions, totaling 138 Megabases, where genomic copies are underrepresented (UR). UR domains originate from a subset of late-replicating heterochromatic regions containing gene deserts and genes involved in cell adhesion and neurogenesis. While lineage-specific CNVs have been identified in mammalian cells, classically in the immune system where V(D)J recombination occurs, we demonstrate that CNVs form during gestation in the placenta by an underreplication mechanism, not by recombination nor deletion. Our results reveal that large scale CNVs are a normal feature of the mammalian placental genome, which are regulated systematically during embryogenesis and are propagated by a mechanism of underreplication.

  12. Copy number variation is a fundamental aspect of the placental genome.

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    Roberta L Hannibal

    2014-05-01

    Full Text Available Discovery of lineage-specific somatic copy number variation (CNV in mammals has led to debate over whether CNVs are mutations that propagate disease or whether they are a normal, and even essential, aspect of cell biology. We show that 1,000 N polyploid trophoblast giant cells (TGCs of the mouse placenta contain 47 regions, totaling 138 Megabases, where genomic copies are underrepresented (UR. UR domains originate from a subset of late-replicating heterochromatic regions containing gene deserts and genes involved in cell adhesion and neurogenesis. While lineage-specific CNVs have been identified in mammalian cells, classically in the immune system where V(DJ recombination occurs, we demonstrate that CNVs form during gestation in the placenta by an underreplication mechanism, not by recombination nor deletion. Our results reveal that large scale CNVs are a normal feature of the mammalian placental genome, which are regulated systematically during embryogenesis and are propagated by a mechanism of underreplication.

  13. Fluorescent in situ hybridization (FISH) assessment of chromosome copy number in sperm

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    Sheu, M.; Sigman, M.; Mark, H.F.L. [Brown Univ. School of Medicine, Providence, RI (United States)

    1994-09-01

    Approximately 15% of all recognized pregnancies end in spontaneous abortions. The overall frequency of chromosome abnormalities in spontaneous abortions is approximately 50%. Thus aneuploidy is a significant cause of fetal wastage. In addition, structural and numerical abnormalities of chromosomes can also lead to birth defects, developmental delay, mental retardation and infertility. Conventional cytogenetic analysis via GTG- and other banding techniques is a powerful tool in the elucidation of the nature of chromosomal abnormalities. Fluorescent in situ hybridization (FISH) enables detection of numerical chromosomal abnormalities, especially trisomies, in intact cells. Using FISH and commercially available biotin-labeled probes, we have initiated a prospective study to assess specific chromosome copy number of preparations of unstained smears from men referred for a male infertility evaluation as well as smears from normal control males chosen randomly from the sample of sperm donors. A total of approximately 19,000 sperm nuclei have been examined thus far. Of those suitable for analysis, 7382 (38.75%) were normal possessing one copy of chromosome 8, 155 (0.81%) were disomic, and 15 (0.079%) had more than two copies of chromosome 8. Comparisons with data available in the literature will be discussed. Work is ongoing to increase the efficiency of hybridization using both reported and previously untried pretreatment and fixation protocols. We have also initiated studies using multicolor FISH with various chromosome enumeration probes. The assay described here is a potentially powerful tool for detecting rare events such as spontaneous germ cell aneuploidy, aneuploidy detected in semen from men with carcinoma in situ of the testis and aneuploidy induced by potential environmental genotoxicants. It can also be utilized for segregation analysis and for correlating chromosome copy number with germ cell morphology.

  14. MET gene copy number predicts worse overall survival in patients with non-small cell lung cancer (NSCLC; a systematic review and meta-analysis.

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    Anastasios Dimou

    Full Text Available OBJECTIVES: MET is a receptor present in the membrane of NSCLC cells and is known to promote cell proliferation, survival and migration. MET gene copy number is a common genetic alteration and inhibition o MET emerges as a promising targeted therapy in NSCLC. Here we aim to combine in a meta-analysis, data on the effect of high MET gene copy number on the overall survival of patients with resected NSCLC. METHODS: Two independent investigators applied parallel search strategies with the terms "MET AND lung cancer", "MET AND NSCLC", "MET gene copy number AND prognosis" in PubMed through January 2014. We selected the studies that investigated the association of MET gene copy number with survival, in patients who received surgery. RESULTS: Among 1096 titles that were identified in the initial search, we retrieved 9 studies on retrospective cohorts with adequate retrievable data regarding the prognostic impact of MET gene copy number on the survival of patients with NSCLC. Out of those, 6 used FISH and the remaining 3 used RT PCR to assess the MET gene copy number in the primary tumor. We calculated the I2 statistic to assess heterogeneity (I2 = 72%. MET gene copy number predicted worse overall survival when all studies were combined in a random effects model (HR = 1.78, 95% CI 1.22-2.60. When only the studies that had at least 50% of adenocarcinoma patients in their populations were included, the effect was significant (five studies, HR 1.55, 95% CI 1.23-1.94. This was not true when we included only the studies with no more than 50% of the patients having adenocarcinoma histology (four studies HR 2.18, 95% CI 0.97-4.90. CONCLUSIONS: Higher MET gene copy number in the primary tumor at the time of diagnosis predicts worse outcome in patients with NSCLC. This prognostic impact may be adenocarcinoma histology specific.

  15. Genomewide profiling of copy-number alteration in monoclonal gammopathy of undetermined significance.

    Science.gov (United States)

    Mikulasova, Aneta; Smetana, Jan; Wayhelova, Marketa; Janyskova, Helena; Sandecka, Viera; Kufova, Zuzana; Almasi, Martina; Jarkovsky, Jiri; Gregora, Evzen; Kessler, Petr; Wrobel, Marek; Walker, Brian A; Wardell, Christopher P; Morgan, Gareth J; Hajek, Roman; Kuglik, Petr

    2016-12-01

    Monoclonal gammopathy of undetermined significance (MGUS) is a benign condition with an approximate 1% annual risk of symptomatic plasma cell disorder development, mostly to multiple myeloma (MM). We performed genomewide screening of copy-number alterations (CNAs) in 90 MGUS and 33 MM patients using high-density DNA microarrays. We identified CNAs in a smaller proportion of MGUS (65.6%) than in MM (100.0%, P = 1.31 × 10(-5) ) and showed median number of CNAs is lower in MGUS (3, range 0-22) than in MM (13, range 4-38, P = 1.82 × 10(-10) ). In the MGUS cohort, the most frequent losses were located at 1p (5.6%), 6q (6.7%), 13q (30.0%), 14q (14.4%), 16q (8.9%), 21q (5.6%), and gains at 1q (23.3%), 2p (6.7%), 6p (13.3%), and Xq (7.8%). Hyperdiploidy was detected in 38.9% of MGUS cases, and the most frequent whole chromosome gains were 3 (25.6%), 5 (23.3%), 9 (37.8%), 15 (23.3%), and 19 (32.2%). We also identified CNAs such as 1p, 6q, 8p, 12p, 13q, 16q losses, 1q gain and hypodiploidy, which are potentially associated with an adverse prognosis in MGUS. In summary, we showed that MGUS is similar to MM in that it is a genetically heterogeneous disorder, but overall cytogenetic instability is lower than in MM, which confirms that genetic abnormalities play important role in monoclonal gammopathies. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. Copy number variation of ribosomal DNA and Pokey transposons in natural populations of Daphnia

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    Eagle Shannon HC

    2012-03-01

    Full Text Available Abstract Background Despite their ubiquity and high diversity in eukaryotic genomes, DNA transposons are rarely encountered in ribosomal DNA (rDNA. In contrast, R-elements, a diverse group of non-LTR retrotransposons, specifically target rDNA. Pokey is a DNA transposon that targets a specific rDNA site, but also occurs in many other genomic locations, unlike R-elements. However, unlike most DNA transposons, Pokey has been a stable component of Daphnia genomes for over 100 million years. Here we use qPCR to estimate the number of 18S and 28S ribosomal RNA genes and Pokey elements in rDNA (rPokey, as well as other genomic locations (gPokey in two species of Daphnia. Our goals are to estimate the correlation between (1 the number of 18S and 28S rRNA genes, (2 the number of 28S genes and rPokey, and (3 the number of rPokey and gPokey. In addition, we ask whether Pokey number and distribution in both genomic compartments are affected by differences in life history between D. pulex and D. pulicaria. Results We found differences in 18S and 28S gene number within isolates that are too large to be explained by experimental variation. In general, Pokey number within isolates is modest (Pokey. There is no correlation between the number of rRNA genes and rPokey, or between rPokey and gPokey. However, we identified three isolates with unusually high numbers of both rPokey and gPokey, which we infer is a consequence of recent transposition. We also detected other rDNA insertions (rInserts that could be degraded Pokey elements, R- elements or the divergent PokeyB lineage recently detected in the Daphnia genome sequence. Unlike rPokey, rInserts are positively correlated with rRNA genes, suggesting that they are amplified by the same mechanisms that amplify rDNA units even though rPokey is not. Overall, Pokey frequency and distribution are similar in D. pulex and D. pulicaria suggesting that differences in life history have no impact on Pokey. Conclusions The

  17. Distinct Copy Number, Coding Sequence, and Locus Methylation Patterns Underlie Rhg1-Mediated Soybean Resistance to Soybean Cyst Nematode1[W][OPEN

    Science.gov (United States)

    Cook, David E.; Bayless, Adam M.; Wang, Kai; Guo, Xiaoli; Song, Qijian; Jiang, Jiming; Bent, Andrew F.

    2014-01-01

    Copy number variation of kilobase-scale genomic DNA segments, beyond presence/absence polymorphisms, can be an important driver of adaptive traits. Resistance to Heterodera glycines (Rhg1) is a widely utilized quantitative trait locus that makes the strongest known contribution to resistance against soybean cyst nematode (SCN), Heterodera glycines, the most damaging pathogen of soybean (Glycine max). Rhg1 was recently discovered to be a complex locus at which resistance-conferring haplotypes carry up to 10 tandem repeat copies of a 31-kb DNA segment, and three disparate genes present on each repeat contribute to SCN resistance. Here, we use whole-genome sequencing, fiber-FISH (fluorescence in situ hybridization), and other methods to discover the genetic variation at Rhg1 across 41 diverse soybean accessions. Based on copy number variation, transcript abundance, nucleic acid polymorphisms, and differentially methylated DNA regions, we find that SCN resistance is associated with multicopy Rhg1 haplotypes that form two distinct groups. The tested high-copy-number Rhg1 accessions, including plant introduction (PI) 88788, contain a flexible number of copies (seven to 10) of the 31-kb Rhg1 repeat. The identified low-copy-number Rhg1 group, including PI 548402 (Peking) and PI 437654, contains three copies of the Rhg1 repeat and a newly identified allele of Glyma18g02590 (a predicted α-SNAP [α-soluble N-ethylmaleimide–sensitive factor attachment protein]). There is strong evidence for a shared origin of the two resistance-conferring multicopy Rhg1 groups and subsequent independent evolution. Differentially methylated DNA regions also were identified within Rhg1 that correlate with SCN resistance. These data provide insights into copy number variation of multigene segments, using as the example a disease resistance trait of high economic importance. PMID:24733883

  18. Antigen-presenting genes and genomic copy number variations in the Tasmanian devil MHC

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    Cheng Yuanyuan

    2012-03-01

    Full Text Available Abstract Background The Tasmanian devil (Sarcophilus harrisii is currently under threat of extinction due to an unusual fatal contagious cancer called Devil Facial Tumour Disease (DFTD. DFTD is caused by a clonal tumour cell line that is transmitted between unrelated individuals as an allograft without triggering immune rejection due to low levels of Major Histocompatibility Complex (MHC diversity in Tasmanian devils. Results Here we report the characterization of the genomic regions encompassing MHC Class I and Class II genes in the Tasmanian devil. Four genomic regions approximately 960 kb in length were assembled and annotated using BAC contigs and physically mapped to devil Chromosome 4q. 34 genes and pseudogenes were identified, including five Class I and four Class II loci. Interestingly, when two haplotypes from two individuals were compared, three genomic copy number variants with sizes ranging from 1.6 to 17 kb were observed within the classical Class I gene region. One deletion is particularly important as it turns a Class Ia gene into a pseudogene in one of the haplotypes. This deletion explains the previously observed variation in the Class I allelic number between individuals. The frequency of this deletion is highest in the northwestern devil population and lowest in southeastern areas. Conclusions The third sequenced marsupial MHC provides insights into the evolution of this dynamic genomic region among the diverse marsupial species. The two sequenced devil MHC haplotypes revealed three copy number variations that are likely to significantly affect immune response and suggest that future work should focus on the role of copy number variations in disease susceptibility in this species.

  19. Copy number variants in candidate genes are genetic modifiers of Hirschsprung disease.

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    Qian Jiang

    Full Text Available Hirschsprung disease (HSCR is a neurocristopathy characterized by absence of intramural ganglion cells along variable lengths of the gastrointestinal tract. The HSCR phenotype is highly variable with respect to gender, length of aganglionosis, familiality and the presence of additional anomalies. By molecular genetic analysis, a minimum of 11 neuro-developmental genes (RET, GDNF, NRTN, SOX10, EDNRB, EDN3, ECE1, ZFHX1B, PHOX2B, KIAA1279, TCF4 are known to harbor rare, high-penetrance mutations that confer a large risk to the bearer. In addition, two other genes (RET, NRG1 harbor common, low-penetrance polymorphisms that contribute only partially to risk and can act as genetic modifiers. To broaden this search, we examined whether a set of 67 proven and candidate HSCR genes harbored additional modifier alleles. In this pilot study, we utilized a custom-designed array CGH with ∼33,000 test probes at an average resolution of ∼185 bp to detect gene-sized or smaller copy number variants (CNVs within these 67 genes in 18 heterogeneous HSCR patients. Using stringent criteria, we identified CNVs at three loci (MAPK10, ZFHX1B, SOX2 that are novel, involve regulatory and coding sequences of neuro-developmental genes, and show association with HSCR in combination with other congenital anomalies. Additional CNVs are observed under relaxed criteria. Our research suggests a role for CNVs in HSCR and, importantly, emphasizes the role of variation in regulatory sequences. A much larger study will be necessary both for replication and for identifying the full spectrum of small CNV effects.

  20. Connecting Anxiety and Genomic Copy Number Variation: A Genome-Wide Analysis in CD-1 Mice.

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    Julia Brenndörfer

    Full Text Available Genomic copy number variants (CNVs have been implicated in multiple psychiatric disorders, but not much is known about their influence on anxiety disorders specifically. Using next-generation sequencing (NGS and two additional array-based genotyping approaches, we detected CNVs in a mouse model consisting of two inbred mouse lines showing high (HAB and low (LAB anxiety-related behavior, respectively. An influence of CNVs on gene expression in the central (CeA and basolateral (BLA amygdala, paraventricular nucleus (PVN, and cingulate cortex (Cg was shown by a two-proportion Z-test (p = 1.6 x 10-31, with a positive correlation in the CeA (p = 0.0062, PVN (p = 0.0046 and Cg (p = 0.0114, indicating a contribution of CNVs to the genetic predisposition to trait anxiety in the specific context of HAB/LAB mice. In order to confirm anxiety-relevant CNVs and corresponding genes in a second mouse model, we further examined CD-1 outbred mice. We revealed the distribution of CNVs by genotyping 64 CD 1 individuals using a high-density genotyping array (Jackson Laboratory. 78 genes within those CNVs were identified to show nominally significant association (48 genes, or a statistical trend in their association (30 genes with the time animals spent on the open arms of the elevated plus-maze (EPM. Fifteen of them were considered promising candidate genes of anxiety-related behavior as we could show a significant overlap (permutation test, p = 0.0051 with genes within HAB/LAB CNVs. Thus, here we provide what is to our knowledge the first extensive catalogue of CNVs in CD-1 mice and potential corresponding candidate genes linked to anxiety-related behavior in mice.

  1. The positioning logic and copy number control of genes in bacteria under stress

    Science.gov (United States)

    Zhang, Qiucen; Austin, Robert; Vyawahare, Saurabh; Lau, Alexandra

    2013-03-01

    Escherichia coli (E. coli) cells when challenged with sublethal concentrations of the genotoxic antibiotic ciprofloxacin cease to divide and form long filaments which contain multiple bacterial chromosomes. These filaments are individual mesoscopic environmental niches which provide protection for a community of chromosomes (as opposed to cells) under mutagenic stress and can provide an evolutionary fitness advantage within the niche. We use comparative genomic hybridization to show that the mesoscopic niche evolves within 20 minutes of ciprofloxacin exposure via replication of multiple copies of genes expressing ATP dependent transporters. We show that this rapid genomic amplification is done in a time efficient manner via placement of the genes encoding the pumps near the origin of replication on the bacterial chromosome. The de-amplification of multiple copies back to the wild type number is a function of the duration is a function of the ciprofloxacin exposure duration: the longer the exposure, the slower the removal of the multiple copies. The project described was supported by the National Science Foundation and the National Cancer Institute

  2. Copy number loss in the region of the ASPN gene in patients with acetabular dysplasia: ASPN CNV in acetabular dysplasia.

    Science.gov (United States)

    Sekimoto, T; Ishii, M; Emi, M; Kurogi, S; Funamoto, T; Yonezawa, Y; Tajima, T; Sakamoto, T; Hamada, H; Chosa, E

    2017-07-01

    We have previously investigated an association between the genome copy number variation (CNV) and acetabular dysplasia (AD). Hip osteoarthritis is associated with a genetic polymorphism in the aspartic acid repeat in the N-terminal region of the asporin (ASPN) gene; therefore, the present study aimed to investigate whether the CNV of ASPN is involved in the pathogenesis of AD. Acetabular coverage of all subjects was evaluated using radiological findings (Sharp angle, centre-edge (CE) angle, acetabular roof obliquity (ARO) angle, and minimum joint space width). Genomic DNA was extracted from peripheral blood leukocytes. Agilent's region-targeted high-density oligonucleotide tiling microarray was used to analyse 64 female AD patients and 32 female control subjects. All statistical analyses were performed using EZR software (Fisher's exact probability test, Pearson's correlation test, and Student's t-test). CNV analysis of the ASPN gene revealed a copy number loss in significantly more AD patients (9/64) than control subjects (0/32; p = 0.0212). This loss occurred within a 60 kb region on 9q22.31, which harbours the gene for ASPN. The mean radiological parameters of these AD patients were significantly worse than those of the other subjects (Sharp angle, p = 0.0056; CE angle, p = 0.0076; ARO angle, p = 0.0065), and all nine patients required operative therapy such as total hip arthroplasty or pelvic osteotomy. Moreover, six of these nine patients had a history of operative or conservative therapy for developmental dysplasia of the hip. Copy number loss within the region harbouring the ASPN gene on 9q22.31 is associated with severe AD. A copy number loss in the ASPN gene region may play a role in the aetiology of severe AD.Cite this article: T. Sekimoto, M. Ishii, M. Emi, S. Kurogi, T. Funamoto, Y. Yonezawa, T. Tajima, T. Sakamoto, H. Hamada, E. Chosa. Copy number loss in the region of the ASPN gene in patients with acetabular dysplasia: ASPN CNV in acetabular

  3. From DNA Copy Number to Gene Expression: Local aberrations, Trisomies and Monosomies

    Science.gov (United States)

    Shay, Tal

    The goal of my PhD research was to study the effect of DNA copy number changes on gene expression. DNA copy number aberrations may be local, encompassing several genes, or on the level of an entire chromosome, such as trisomy and monosomy. The main dataset I studied was of Glioblastoma, obtained in the framework of a collaboration, but I worked also with public datasets of cancer and Down's Syndrome. The molecular basis of expression changes in Glioblastoma. Glioblastoma is the most common and aggressive type of primary brain tumors in adults. In collaboration with Prof. Hegi (CHUV, Switzerland), we analyzed a rich Glioblastoma dataset including clinical information, DNA copy number (array CGH) and expression profiles. We explored the correlation between DNA copy number and gene expression at the level of chromosomal arms and local genomic aberrations. We detected known amplification and over expression of oncogenes, as well as deletion and down-regulation of tumor suppressor genes. We exploited that information to map alterations of pathways that are known to be disrupted in Glioblastoma, and tried to characterize samples that have no known alteration in any of the studied pathways. Identifying local DNA aberrations of biological significance. Many types of tumors exhibit chromosomal losses or gains and local amplifications and deletions. A region that is aberrant in many tumors, or whose copy number change is stronger, is more likely to be clinically relevant, and not just a by-product of genetic instability. We developed a novel method that defines and prioritizes aberrations by formalizing these intuitions. The method scores each aberration by the fraction of patients harboring it, its length and its amplitude, and assesses the significance of the score by comparing it to a null distribution obtained by permutations. This approach detects genetic locations that are significantly aberrant, generating a 'genomic aberration profile' for each sample. The 'genomic

  4. Peer—to—Peer Computing for secure High Performance Data Copying

    Institute of Scientific and Technical Information of China (English)

    AndrewHanushevsky; ArtemTrunov; 等

    2001-01-01

    The BaBar Copy Program(bbcp) is an excellent representative of peer-to-peer(P2P) computing.It is also a pioneering application of its type in the p2p arena.Built upon the foundation of its predecessor,Secure Fast Copy(sfctp),bbcp incorporates significant improvements performance and usability,As with sfcp,bbcp usec ssh for authentication;providing an elegant and simple working model-if you can ssh to a location, you can copy files to or from that location.To fully support this notion,bbcp transparently supports 3rd party copy operations.The program also incorporates several mechanism to deal with firewall security;the bane of P2P computing,To achieve high performance in a wide area network,bbcp allows a user to independently specily,the number of parallel network streams,tcp window size,and the file I/O blocking factor.Using these parameters data is pipelined from source to target to provide a uniform traffic pattern that maximizes router efficiency.For improved recoveralbiltiy,bbcp also keeps track of copy operations so that an operation can be restarted from the point of failure at a later time;minimizing the amount of network traffic in the event of a copy failure,Here,we preset the bbcp architecture,it's various features,and the reasons for their inclusion.

  5. Association study of copy number variants in FCGR3A and FCGR3B gene with risk of ankylosing spondylitis in a Chinese population.

    Science.gov (United States)

    Wang, Li; Yang, Xiao; Cai, Guoqi; Xin, Lihong; Xia, Qing; Zhang, Xu; Li, Xiaona; Wang, Mengmeng; Wang, Kang; Xia, Guo; Xu, Shengqian; Xu, Jianhua; Zou, Yanfeng; Pan, Faming

    2016-03-01

    Ankylosing spondylitis (AS) is a common inherited autoimmune disease. Copy number variation (CNV) of DNA segments has been found to be an important part of genetic variation, and the FCGR3A and FCGR3B gene CNVs have been associated with various autoimmune disorders. The aim of the study was to determine whether CNVs of FCGR3A and FCGR3B were also associated with the susceptibility of AS. A total of 801 individuals including 402 AS patients and 399 healthy controls were enrolled in this study. The copy numbers of FCGR3 gene (two fragments, included FCGR3A and FCGR3B) were measured by AccuCopy™ methods. Chi-square test and logistic regression model were used to evaluate association between FCGR3 gene CNVs and AS susceptibility. P values, odds ratio, and 95% confidence intervals (CIs) were used to estimate the effects of risk. Significantly, difference in the frequencies of FCGR3A and FCGR3B gene CNVs was founded between the patients with AS and controls. For the FCGR3A gene, a low (≤3) copy number was significantly associated with AS [for ≤3 copies versus 4 copies, (OR 2.17, 95% CI (1.41, 3.34), P < 0.001, adjusted OR 2.22, 95% CI (1.44, 3.43), P < 0.001)]. A low FCGR3B copy number was also significantly associated with increasing risk of AS [for ≤3 copies versus 4 copies, (OR 1.87, 95% CI (1.25, 2.79), P = 0.002, adjusted OR 1.94, 95% CI (1.29, 2.91), P = 0.001)]; however, both the high FCGR3A and FCGR3B copy numbers (≥5) were not significantly associated with the risk of AS (≥5 copies versus 4 copies). The lower copy numbers (≤3) of FCGR3A and FCGR3B genes confer a risk factor for AS susceptibility.

  6. Focal DNA copy number changes in neuroblastoma target MYCN regulated genes.

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    Candy Kumps

    Full Text Available Neuroblastoma is an embryonic tumor arising from immature sympathetic nervous system cells. Recurrent genomic alterations include MYCN and ALK amplification as well as recurrent patterns of gains and losses of whole or large partial chromosome segments. A recent whole genome sequencing effort yielded no frequently recurring mutations in genes other than those affecting ALK. However, the study further stresses the importance of DNA copy number alterations in this disease, in particular for genes implicated in neuritogenesis. Here we provide additional evidence for the importance of focal DNA copy number gains and losses, which are predominantly observed in MYCN amplified tumors. A focal 5 kb gain encompassing the MYCN regulated miR-17~92 cluster as sole gene was detected in a neuroblastoma cell line and further analyses of the array CGH data set demonstrated enrichment for other MYCN target genes in focal gains and amplifications. Next we applied an integrated genomics analysis to prioritize MYCN down regulated genes mediated by MYCN driven miRNAs within regions of focal heterozygous or homozygous deletion. We identified RGS5, a negative regulator of G-protein signaling implicated in vascular normalization, invasion and metastasis, targeted by a focal homozygous deletion, as a new MYCN target gene, down regulated through MYCN activated miRNAs. In addition, we expand the miR-17~92 regulatory network controlling TGFß signaling in neuroblastoma with the ring finger protein 11 encoding gene RNF11, which was previously shown to be targeted by the miR-17~92 member miR-19b. Taken together, our data indicate that focal DNA copy number imbalances in neuroblastoma (1 target genes that are implicated in MYCN signaling, possibly selected to reinforce MYCN oncogene addiction and (2 serve as a resource for identifying new molecular targets for treatment.

  7. Tumor transcriptome sequencing reveals allelic expression imbalances associated with copy number alterations.

    Directory of Open Access Journals (Sweden)

    Brian B Tuch

    Full Text Available Due to growing throughput and shrinking cost, massively parallel sequencing is rapidly becoming an attractive alternative to microarrays for the genome-wide study of gene expression and copy number alterations in primary tumors. The sequencing of transcripts (RNA-Seq should offer several advantages over microarray-based methods, including the ability to detect somatic mutations and accurately measure allele-specific expression. To investigate these advantages we have applied a novel, strand-specific RNA-Seq method to tumors and matched normal tissue from three patients with oral squamous cell carcinomas. Additionally, to better understand the genomic determinants of the gene expression changes observed, we have sequenced the tumor and normal genomes of one of these patients. We demonstrate here that our RNA-Seq method accurately measures allelic imbalance and that measurement on the genome-wide scale yields novel insights into cancer etiology. As expected, the set of genes differentially expressed in the tumors is enriched for cell adhesion and differentiation functions, but, unexpectedly, the set of allelically imbalanced genes is also enriched for these same cancer-related functions. By comparing the transcriptomic perturbations observed in one patient to his underlying normal and tumor genomes, we find that allelic imbalance in the tumor is associated with copy number mutations and that copy number mutations are, in turn, strongly associated with changes in transcript abundance. These results support a model in which allele-specific deletions and duplications drive allele-specific changes in gene expression in the developing tumor.

  8. Critical evaluation of HPV16 gene copy number quantification by SYBR green PCR

    Directory of Open Access Journals (Sweden)

    Pett Mark R

    2008-07-01

    Full Text Available Abstract Background Human papilloma virus (HPV load and physical status are considered useful parameters for clinical evaluation of cervical squamous cell neoplasia. However, the errors implicit in HPV gene quantification by PCR are not well documented. We have undertaken the first rigorous evaluation of the errors that can be expected when using SYBR green qPCR for quantification of HPV type 16 gene copy numbers. We assessed a modified method, in which external calibration curves were generated from a single construct containing HPV16 E2, HPV16 E6 and the host gene hydroxymethylbilane synthase in a 1:1:1 ratio. Results When testing dilutions of mixed HPV/host DNA in replicate runs, we observed errors in quantifying E2 and E6 amplicons of 5–40%, with greatest error at the lowest DNA template concentration (3 ng/μl. Errors in determining viral copy numbers per diploid genome were 13–53%. Nevertheless, in cervical keratinocyte cell lines we observed reasonable agreement between viral loads determined by qPCR and Southern blotting. The mean E2/E6 ratio in episome-only cells was 1.04, but with a range of 0.76–1.32. In three integrant-only lines the mean E2/E6 ratios were 0.20, 0.72 and 2.61 (values confirmed by gene-specific Southern blotting. When E2/E6 ratios in fourteen HPV16-positive cervical carcinomas were analysed, conclusions regarding viral physical state could only be made in three cases, where the E2/E6 ratio was ≤ 0.06. Conclusion Run-to-run variation in SYBR green qPCR produces unavoidable inaccuracies that should be allowed for when quantifying HPV gene copy number. While E6 copy numbers can be considered to provide a useable indication of viral loads, the E2/E6 ratio is of limited value. Previous studies may have overestimated the frequency of mixed episomal/integrant HPV infections.

  9. Copy number variations of chromosome 16p13.1 region associated with schizophrenia

    DEFF Research Database (Denmark)

    Ingason, A; Rujescu, D; Cichon, S

    2011-01-01

    Deletions and reciprocal duplications of the chromosome 16p13.1 region have recently been reported in several cases of autism and mental retardation (MR). As genomic copy number variants found in these two disorders may also associate with schizophrenia, we examined 4345 schizophrenia patients an...... disorder and dyslexia. Candidate genes in the region include NTAN1 and NDE1. We conclude that duplications and perhaps also deletions of chromosome 16p13.1, previously reported to be associated with autism and MR, also confer risk of schizophrenia....

  10. Global copy number profiling of cancer genomes | Office of Cancer Genomics

    Science.gov (United States)

    In this article, we introduce a robust and efficient strategy for deriving global and allele-specific copy number alternations (CNA) from cancer whole exome sequencing data based on Log R ratios and B-allele frequencies. Applying the approach to the analysis of over 200 skin cancer samples, we demonstrate its utility for discovering distinct CNA events and for deriving ancillary information such as tumor purity. Availability and implementation: https://github.com/xfwang/CLOSE CONTACT: xuefeng.wang@stonybrook.edu or michael.krauthammer@yale.edu. (Publication Abstract)

  11. Genomic copy number variation associated with clinical outcome in canine cutaneous mast cell tumors

    DEFF Research Database (Denmark)

    Jark, Paulo C; Mundin, Deborah B P; de Carvalho, Marcio

    2017-01-01

    from Group ST>12 and six from Group STGenomic DNA was extracted, and aCGH was performed using Agilent Canine Genome CGH Microarray 4×180 (ID-252 552 - Agilent, USA). Data analysis was carried out using Nexus program version 5.0 (Biodiscovery, USA). The group ST>12 presented 11±3.3 CNVs, while...... in DNA isolated from tumor cells by array comparative genomic hybridization (aCGH). The aim of this study was to compare copy number variations (CNVs) in cutaneous mast cell tumors of dogs that survived less than six (ST12months (ST>12) from the date of diagnosis. Ten animals were used: four...

  12. TOP1 gene copy number and TOP1/CEN-20 ratio in stage III colorectal cancer samples

    DEFF Research Database (Denmark)

    Rømer, Maria Unni Koefoed; Nygård, Sune Boris; Christensen, Ib Jarle

    AIM OF STUDY To investigate if TOP1 gene copy number and/or the TOP1/CEN-20 ratio in colorectal cancer (CRC) areassociated with prognosis. BACKGROUND TOP1, localized on chromosome 20, encodes topoisomerase I (TOP1), which is the sole molecular target of irinotecan. TOP1 immunoreactivity in formalin...... analyses on 50 FFPE primary CRC tissues. When compared with results from normal colorectal mucosa, 80 % of the tumors showed increased TOP1 gene copy number and 2/3 had increased TOP1/CEN-20 ratio. MATERIALS AND METHODS FFPE samples from 154 stage III CRC patients not receiving adjuvant chemotherapy were...... included. For each patient TOP1 gene copy number and CEN-20 reference number were determined in 60 nuclei from the malignant tumor by FISH using a TOP1/CEN-20 probe mix. Similarly, the TOP1 gene copy number and and CEN-20 reference number were dertermined in the normal colorectal mucosa in 105 of the 154...

  13. Differences in AMY1 Gene Copy Numbers Derived from Blood, Buccal Cells and Saliva Using Quantitative and Droplet Digital PCR Methods: Flagging the Pitfall.

    Science.gov (United States)

    Ooi, Delicia Shu Qin; Tan, Verena Ming Hui; Ong, Siong Gim; Chan, Yiong Huak; Heng, Chew Kiat; Lee, Yung Seng

    2017-01-01

    The human salivary (AMY1) gene, encoding salivary α-amylase, has variable copy number variants (CNVs) in the human genome. We aimed to determine if real-time quantitative polymerase chain reaction (qPCR) and the more recently available Droplet Digital PCR (ddPCR) can provide a precise quantification of the AMY1 gene copy number in blood, buccal cells and saliva samples derived from the same individual. Seven participants were recruited and DNA was extracted from the blood, buccal cells and saliva samples provided by each participant. Taqman assay real-time qPCR and ddPCR were conducted to quantify AMY1 gene copy numbers. Statistical analysis was carried out to determine the difference in AMY1 gene copy number between the different biological specimens and different assay methods. We found significant within-individual difference (pcopy number between different biological samples as determined by qPCR. However, there was no significant within-individual difference in AMY1 gene copy number between different biological samples as determined by ddPCR. We also found that AMY1 gene copy number of blood samples were comparable between qPCR and ddPCR, while there is a significant difference (pcopy numbers measured by qPCR and ddPCR for both buccal swab and saliva samples. Despite buccal cells and saliva samples being possible sources of DNA, it is pertinent that ddPCR or a single biological sample, preferably blood sample, be used for determining highly polymorphic gene copy numbers like AMY1, due to the large within-individual variability between different biological samples if real time qPCR is employed.

  14. Obesity, starch digestion and amylase: association between copy number variants at human salivary (AMY1) and pancreatic (AMY2) amylase genes.

    Science.gov (United States)

    Carpenter, Danielle; Dhar, Sugandha; Mitchell, Laura M; Fu, Beiyuan; Tyson, Jess; Shwan, Nzar A A; Yang, Fengtang; Thomas, Mark G; Armour, John A L

    2015-06-15

    The human salivary amylase genes display extensive copy number variation (CNV), and recent work has implicated this variation in adaptation to starch-rich diets, and in association with body mass index. In this work, we use paralogue ratio tests, microsatellite analysis, read depth and fibre-FISH to demonstrate that human amylase CNV is not a smooth continuum, but is instead partitioned into distinct haplotype classes. There is a fundamental structural distinction between haplotypes containing odd or even numbers of AMY1 gene units, in turn coupled to CNV in pancreatic amylase genes AMY2A and AMY2B. Most haplotypes have one copy each of AMY2A and AMY2B and contain an odd number of copies of AMY1; consequently, most individuals have an even total number of AMY1. In contrast, haplotypes carrying an even number of AMY1 genes have rearrangements leading to CNVs of AMY2A/AMY2B. Read-depth and experimental data show that different populations harbour different proportions of these basic haplotype classes. In Europeans, the copy numbers of AMY1 and AMY2A are correlated, so that phenotypic associations caused by variation in pancreatic amylase copy number could be detected indirectly as weak association with AMY1 copy number. We show that the quantitative polymerase chain reaction (qPCR) assay previously applied to the high-throughput measurement of AMY1 copy number is less accurate than the measures we use and that qPCR data in other studies have been further compromised by systematic miscalibration. Our results uncover new patterns in human amylase variation and imply a potential role for AMY2 CNV in functional associations.

  15. Systematic prioritization and integrative analysis of copy number variations in schizophrenia reveal key schizophrenia susceptibility genes.

    Science.gov (United States)

    Luo, Xiongjian; Huang, Liang; Han, Leng; Luo, Zhenwu; Hu, Fang; Tieu, Roger; Gan, Lin

    2014-11-01

    Schizophrenia is a common mental disorder with high heritability and strong genetic heterogeneity. Common disease-common variants hypothesis predicts that schizophrenia is attributable in part to common genetic variants. However, recent studies have clearly demonstrated that copy number variations (CNVs) also play pivotal roles in schizophrenia susceptibility and explain a proportion of missing heritability. Though numerous CNVs have been identified, many of the regions affected by CNVs show poor overlapping among different studies, and it is not known whether the genes disrupted by CNVs contribute to the risk of schizophrenia. By using cumulative scoring, we systematically prioritized the genes affected by CNVs in schizophrenia. We identified 8 top genes that are frequently disrupted by CNVs, including NRXN1, CHRNA7, BCL9, CYFIP1, GJA8, NDE1, SNAP29, and GJA5. Integration of genes affected by CNVs with known schizophrenia susceptibility genes (from previous genetic linkage and association studies) reveals that many genes disrupted by CNVs are also associated with schizophrenia. Further protein-protein interaction (PPI) analysis indicates that protein products of genes affected by CNVs frequently interact with known schizophrenia-associated proteins. Finally, systematic integration of CNVs prioritization data with genetic association and PPI data identifies key schizophrenia candidate genes. Our results provide a global overview of genes impacted by CNVs in schizophrenia and reveal a densely interconnected molecular network of de novo CNVs in schizophrenia. Though the prioritized top genes represent promising schizophrenia risk genes, further work with different prioritization methods and independent samples is needed to confirm these findings. Nevertheless, the identified key candidate genes may have important roles in the pathogenesis of schizophrenia, and further functional characterization of these genes may provide pivotal targets for future therapeutics and

  16. Novel amplifications in pediatric medulloblastoma identified by genome-wide copy number profiling.

    Science.gov (United States)

    Nord, Helena; Pfeifer, Susan; Nilsson, Pelle; Sandgren, Johanna; Popova, Svetlana; Strömberg, Bo; Alafuzoff, Irina; Nistér, Monica; Díaz de Ståhl, Teresita

    2012-03-01

    Medulloblastoma (MB) is a WHO grade IV, invasive embryonal CNS tumor that mainly affects children. The aggressiveness and response to therapy can vary considerably between cases, and despite treatment, ~30% of patients die within 2 years from diagnosis. Furthermore, the majority of survivors suffer long-term side-effects due to severe management modalities. Several distinct morphological features have been associated with differences in biological behavior, but improved molecular-based criteria that better reflect the underlying tumor biology are in great demand. In this study, we profiled a series of 25 MB with a 32K BAC array covering 99% of the current assembly of the human genome for the identification of genetic copy number alterations possibly important in MB. Previously known aberrations as well as several novel focally amplified loci could be identified. As expected, the most frequently observed alteration was the combination of 17p loss and 17q gain, which was detected in both high- and standard-risk patients. We also defined minimal overlapping regions of aberrations, including 16 regions of gain and 18 regions of loss in various chromosomes. A few noteworthy narrow amplified loci were identified on autosomes 1 (38.89-41.97 and 84.89-90.76 Mb), 3 (27.64-28.20 and 35.80-43.50 Mb), and 8 (119.66-139.79 Mb), aberrations that were verified with an alternative platform (Illumina 610Q chips). Gene expression levels were also established for these samples using Affymetrix U133Plus2.0 arrays. Several interesting genes encompassed within the amplified regions and presenting with transcript upregulation were identified. These data contribute to the characterization of this malignant childhood brain tumor and confirm its genetic heterogeneity.

  17. A genome-wide investigation of copy number variation in patients with sporadic brain arteriovenous malformation.

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    Nasrine Bendjilali

    Full Text Available BACKGROUND: Brain arteriovenous malformations (BAVM are clusters of abnormal blood vessels, with shunting of blood from the arterial to venous circulation and a high risk of rupture and intracranial hemorrhage. Most BAVMs are sporadic, but also occur in patients with Hereditary Hemorrhagic Telangiectasia, a Mendelian disorder caused by mutations in genes in the transforming growth factor beta (TGFβ signaling pathway. METHODS: To investigate whether copy number variations (CNVs contribute to risk of sporadic BAVM, we performed a genome-wide association study in 371 sporadic BAVM cases and 563 healthy controls, all Caucasian. Cases and controls were genotyped using the Affymetrix 6.0 array. CNVs were called using the PennCNV and Birdsuite algorithms and analyzed via segment-based and gene-based approaches. Common and rare CNVs were evaluated for association with BAVM. RESULTS: A CNV region on 1p36.13, containing the neuroblastoma breakpoint family, member 1 gene (NBPF1, was significantly enriched with duplications in BAVM cases compared to controls (P = 2.2×10(-9; NBPF1 was also significantly associated with BAVM in gene-based analysis using both PennCNV and Birdsuite. We experimentally validated the 1p36.13 duplication; however, the association did not replicate in an independent cohort of 184 sporadic BAVM cases and 182 controls (OR = 0.81, P = 0.8. Rare CNV analysis did not identify genes significantly associated with BAVM. CONCLUSION: We did not identify common CNVs associated with sporadic BAVM that replicated in an independent cohort. Replication in larger cohorts is required to elucidate the possible role of common or rare CNVs in BAVM pathogenesis.

  18. A Poisson hierarchical modelling approach to detecting copy number variation in sequence coverage data

    KAUST Repository

    Sepúlveda, Nuno

    2013-02-26

    Background: The advent of next generation sequencing technology has accelerated efforts to map and catalogue copy number variation (CNV) in genomes of important micro-organisms for public health. A typical analysis of the sequence data involves mapping reads onto a reference genome, calculating the respective coverage, and detecting regions with too-low or too-high coverage (deletions and amplifications, respectively). Current CNV detection methods rely on statistical assumptions (e.g., a Poisson model) that may not hold in general, or require fine-tuning the underlying algorithms to detect known hits. We propose a new CNV detection methodology based on two Poisson hierarchical models, the Poisson-Gamma and Poisson-Lognormal, with the advantage of being sufficiently flexible to describe different data patterns, whilst robust against deviations from the often assumed Poisson model.Results: Using sequence coverage data of 7 Plasmodium falciparum malaria genomes (3D7 reference strain, HB3, DD2, 7G8, GB4, OX005, and OX006), we showed that empirical coverage distributions are intrinsically asymmetric and overdispersed in relation to the Poisson model. We also demonstrated a low baseline false positive rate for the proposed methodology using 3D7 resequencing data and simulation. When applied to the non-reference isolate data, our approach detected known CNV hits, including an amplification of the PfMDR1 locus in DD2 and a large deletion in the CLAG3.2 gene in GB4, and putative novel CNV regions. When compared to the recently available FREEC and cn.MOPS approaches, our findings were more concordant with putative hits from the highest quality array data for the 7G8 and GB4 isolates.Conclusions: In summary, the proposed methodology brings an increase in flexibility, robustness, accuracy and statistical rigour to CNV detection using sequence coverage data. 2013 Seplveda et al.; licensee BioMed Central Ltd.

  19. Novel population specific autosomal copy number variation and its functional analysis amongst Negritos from Peninsular Malaysia.

    Science.gov (United States)

    Mokhtar, Siti Shuhada; Marshall, Christian R; Phipps, Maude E; Thiruvahindrapuram, Bhooma; Lionel, Anath C; Scherer, Stephen W; Peng, Hoh Boon

    2014-01-01

    Copy number variation (CNV) has been recognized as a major contributor to human genome diversity. It plays an important role in determining phenotypes and has been associated with a number of common and complex diseases. However CNV data from diverse populations is still limited. Here we report the first investigation of CNV in the indigenous populations from Peninsular Malaysia. We genotyped 34 Negrito genomes from Peninsular Malaysia using the Affymetrix SNP 6.0 microarray and identified 48 putative novel CNVs, consisting of 24 gains and 24 losses, of which 5 were identified in at least 2 unrelated samples. These CNVs appear unique to the Negrito population and were absent in the DGV, HapMap3 and Singapore Genome Variation Project (SGVP) datasets. Analysis of gene ontology revealed that genes within these CNVs were enriched in the immune system (GO:0002376), response to stimulus mechanisms (GO:0050896), the metabolic pathways (GO:0001852), as well as regulation of transcription (GO:0006355). Copy number gains in CNV regions (CNVRs) enriched with genes were significantly higher than the losses (P value Malaysia.

  20. NF1 single and multi-exons copy number variations in neurofibromatosis type 1.

    Science.gov (United States)

    Imbard, Apolline; Pasmant, Eric; Sabbagh, Audrey; Luscan, Armelle; Soares, Magali; Goussard, Philippe; Blanché, Hélène; Laurendeau, Ingrid; Ferkal, Salah; Vidaud, Michel; Pinson, Stéphane; Bellanne-Chantelot, Christine; Vidaud, Dominique; Wolkenstein, Pierre; Parfait, Béatrice

    2015-04-01

    Neurofibromatosis type 1 (NF1) is caused by dominant loss-of-function mutations of the tumor suppressor NF1 containing 57 constitutive coding exons. A huge number of different pathogenic NF1 alterations has been reported. The aim of the present study was to evaluate the usefulness of a multiplex ligation-dependent probe amplification (MLPA) approach in NF1 patients to detect single and multi-exon NF1 gene copy number variations. A genotype-phenotype correlation was then performed in NF1 patients carrying these types of genetic alterations. Among 565 NF1 index cases from the French NF1 cohort, single and multi-exon deletions/duplications screening identified NF1 partial deletions/duplications in 22 patients (~4%) using MLPA analysis. Eight single exon deletions, 11 multiple exons deletions, 1 complex rearrangement and 2 duplications were identified. All results were confirmed using a custom array-CGH. MLPA and custom array-CGH allowed the identification of rearrangements that were missed by cDNA/DNA sequencing or microsatellite analysis. We then performed a targeted next-generation sequencing of NF1 that allowed confirmation of all 22 rearrangements. No clear genotype-phenotype correlations were found for the most clinically significant disease features of NF1 in patients with single and multi-exons NF1 gene copy number changes.

  1. A Method for Generating New Datasets Based on Copy Number for Cancer Analysis

    Directory of Open Access Journals (Sweden)

    Shinuk Kim

    2015-01-01

    Full Text Available New data sources for the analysis of cancer data are rapidly supplementing the large number of gene-expression markers used for current methods of analysis. Significant among these new sources are copy number variation (CNV datasets, which typically enumerate several hundred thousand CNVs distributed throughout the genome. Several useful algorithms allow systems-level analyses of such datasets. However, these rich data sources have not yet been analyzed as deeply as gene-expression data. To address this issue, the extensive toolsets used for analyzing expression data in cancerous and noncancerous tissue (e.g., gene set enrichment analysis and phenotype prediction could be redirected to extract a great deal of predictive information from CNV data, in particular those derived from cancers. Here we present a software package capable of preprocessing standard Agilent copy number datasets into a form to which essentially all expression analysis tools can be applied. We illustrate the use of this toolset in predicting the survival time of patients with ovarian cancer or glioblastoma multiforme and also provide an analysis of gene- and pathway-level deletions in these two types of cancer.

  2. A meta-analysis of multiple matched copy number and transcriptomics data sets for inferring gene regulatory relationships.

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    Richard Newton

    Full Text Available Inferring gene regulatory relationships from observational data is challenging. Manipulation and intervention is often required to unravel causal relationships unambiguously. However, gene copy number changes, as they frequently occur in cancer cells, might be considered natural manipulation experiments on gene expression. An increasing number of data sets on matched array comparative genomic hybridisation and transcriptomics experiments from a variety of cancer pathologies are becoming publicly available. Here we explore the potential of a meta-analysis of thirty such data sets. The aim of our analysis was to assess the potential of in silico inference of trans-acting gene regulatory relationships from this type of data. We found sufficient correlation signal in the data to infer gene regulatory relationships, with interesting similarities between data sets. A number of genes had highly correlated copy number and expression changes in many of the data sets and we present predicted potential trans-acted regulatory relationships for each of these genes. The study also investigates to what extent heterogeneity between cell types and between pathologies determines the number of statistically significant predictions available from a meta-analysis of experiments.

  3. Reduced rDNA Copy Number Does Not Affect “Competitive” Chromosome Pairing in XYY Males of Drosophila melanogaster

    OpenAIRE

    Keith A. Maggert

    2014-01-01

    The ribosomal DNA (rDNA) arrays are causal agents in X-Y chromosome pairing in meiosis I of Drosophila males. Despite broad variation in X-linked and Y-linked rDNA copy number, polymorphisms in regulatory/spacer sequences between rRNA genes, and variance in copy number of interrupting R1 and R2 retrotransposable elements, there is little evidence that different rDNA arrays affect pairing efficacy. I investigated whether induced rDNA copy number polymorphisms affect chromosome pairing in a “co...

  4. HIV Replication at Low Copy Number and its Correlation with the HIV Reservoir: A Clinical Perspective.

    Science.gov (United States)

    Sarmati, Loredana; D'Ettorre, Gabriella; Parisi, Saverio Giuseppe; Andreoni, Massimo

    2015-01-01

    The efficacy of combination therapy (antiretroviral therapy--ARV) is demonstrated by the high rates of viral suppression achieved in most treated HIV patients. Whereas contemporary treatments may continuously suppress HIV replication, they do not eliminate the latent reservoir, which can reactivate HIV infection if ARV is discontinued. The persistence of HIV proviral DNA and infectious viruses in CD4+ T cells and others cells has long been considered a major obstacle in eradicating the HIV virus in treated patients. Moreover, recent studies have demonstrated the persistence of HIV replication at low copies in most patients on suppressive ARV. The source of this 'residual viraemia' and whether it declines over years of therapy remain unknown. Similarly, little is known regarding the biological relationships between the HIV reservoir and viral replication at low copies. The question of whether this 'residual viraemia' represents active replication or the release of non-productive virus from the reservoir has not been adequately resolved. From a clinical perspective, both the quantification of the HIV reservoir and the detection of low levels of replication in full-responder patients on prolonged ARV may provide important information regarding the effectiveness of treatment and the eradication of HIV. To date, the monitoring of these two parameters has been conducted only for research purposes; the routine use of standardised tests procedure is lacking. This review aims to assess the current data regarding the correlation between HIV replication at low copies and the HIV reservoir and to provide useful information for clinicians.

  5. Germline DNA copy number aberrations identified as potential prognostic factors for breast cancer recurrence.

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    Yadav Sapkota

    Full Text Available Breast cancer recurrence (BCR is a common treatment outcome despite curative-intent primary treatment of non-metastatic breast cancer. Currently used prognostic and predictive factors utilize tumor-based markers, and are not optimal determinants of risk of BCR. Germline-based copy number aberrations (CNAs have not been evaluated as determinants of predisposition to experience BCR. In this study, we accessed germline DNA from 369 female breast cancer subjects who received curative-intent primary treatment following diagnosis. Of these, 155 experienced BCR and 214 did not, after a median duration of follow up after breast cancer diagnosis of 6.35 years (range = 0.60-21.78 and 8.60 years (range = 3.08-13.57, respectively. Whole genome CNA genotyping was performed on the Affymetrix SNP array 6.0 platform. CNAs were identified using the SNP-Fast Adaptive States Segmentation Technique 2 algorithm implemented in Nexus Copy Number 6.0. Six samples were removed due to poor quality scores, leaving 363 samples for further analysis. We identified 18,561 CNAs with ≥1 kb as a predefined cut-off for observed aberrations. Univariate survival analyses (log-rank tests identified seven CNAs (two copy number gains and five copy neutral-loss of heterozygosities, CN-LOHs showing significant differences (P<2.01×10(-5 in recurrence-free survival (RFS probabilities with and without CNAs.We also observed three additional but distinct CN-LOHs showing significant differences in RFS probabilities (P<2.86×10(-5 when analyses were restricted to stratified cases (luminal A, n = 208 only. After adjusting for tumor stage and grade in multivariate analyses (Cox proportional hazards models, all the CNAs remained strongly associated with the phenotype of BCR. Of these, we confirmed three CNAs at 17q11.2, 11q13.1 and 6q24.1 in representative samples using independent genotyping platforms. Our results suggest further investigations on the potential use of germline DNA

  6. Dosage-dependent severity of the phenotype in patients with mental retardation due to a recurrent copy-number gain at Xq28 mediated by an unusual recombination.

    Science.gov (United States)

    Vandewalle, Joke; Van Esch, Hilde; Govaerts, Karen; Verbeeck, Jelle; Zweier, Christiane; Madrigal, Irene; Mila, Montserrat; Pijkels, Elly; Fernandez, Isabel; Kohlhase, Jürgen; Spaich, Christiane; Rauch, Anita; Fryns, Jean-Pierre; Marynen, Peter; Froyen, Guy

    2009-12-01

    We report on the identification of a 0.3 Mb inherited recurrent but variable copy-number gain at Xq28 in affected males of four unrelated families with X-linked mental retardation (MR). All aberrations segregate with the disease in the families, and the carrier mothers show nonrandom X chromosome inactivation. Tiling Xq28-region-specific oligo array revealed that all aberrations start at the beginning of the low copy repeat LCR-K1, at position 153.20 Mb, and end just distal to LCR-L2, at 153.54 Mb. The copy-number gain always includes 18 annotated genes, of which RPL10, ATP6AP1 and GDI1 are highly expressed in brain. From these, GDI1 is the most likely candidate gene. Its copy number correlates with the severity of clinical features, because it is duplicated in one family with nonsyndromic moderate MR, is triplicated in males from two families with mild MR and additional features, and is present in five copies in a fourth family with a severe syndromic form of MR. Moreover, expression analysis revealed copy-number-dependent increased mRNA levels in affected patients compared to control individuals. Interestingly, analysis of the breakpoint regions suggests a recombination mechanism that involves two adjacent but different sets of low copy repeats. Taken together, our data strongly suggest that an increased expression of GDI1 results in impaired cognition in a dosage-dependent manner. Moreover, these data also imply that a copy-number gain of an individual gene present in the larger genomic aberration that leads to the severe MECP2 duplication syndrome can of itself result in a clinical phenotype as well.

  7. Optimization protein productivity of human interleukin-2 through codon usage, gene copy number and intracellular tRNA concentration in CHO cells.

    Science.gov (United States)

    Ou, Kua-Chun; Wang, Chih-Yang; Liu, Kuan-Ting; Chen, Yi-Ling; Chen, Yi-Chen; Lai, Ming-Derg; Yen, Meng-Chi

    2014-11-14

    Transfer RNA (tRNA) abundance is one of the critical factors for the enhancement of protein productivity in prokaryotic and eukaryotic hosts. Gene copy number of tRNA and tRNA codon usage bias are generally used to match tRNA abundance of protein-expressing hosts and to optimize the codons of recombinant proteins. Because sufficient concentration of intracellular tRNA and optimized codons of recombinant proteins enhanced translation efficiency, we hypothesized that sufficient supplement of host's tRNA improved protein productivity in mammalian cells. First, the small tRNA sequencing results of CHO-K1 cells showed moderate positive correlation with gene copy number and codon usage bias. Modification of human interleukin-2 (IL-2) through codons with high gene copy number and high codon usage bias (IL-2 HH, modified on Leu, Thr, Glu) significantly increased protein productivity in CHO-K1 cells. In contrast, modification through codons with relatively high gene copy number and low codon usage bias (IL-2 HL, modified on Ala, Thr, Val), or relatively low gene copy number and low codon usage bias (IL-2 LH, modified on Ala, Thr, Val) did not increase IL-2 productivity significantly. Furthermore, supplement of the alanine tRNA or threonine tRNA increased IL-2 productivity of IL-2 HL. In summary, we revealed a potential strategy to enhance productivity of recombinant proteins, which may be applied in production of protein drug or design of DNA vaccine.

  8. CNVrd, a read-depth algorithm for assigning copy-number at the FCGR locus: population-specific tagging of copy number variation at FCGR3B.

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    Hoang tan Nguyen

    Full Text Available The extent of contribution from common gene copy number (CN variants in human disease is currently unresolved. Part of the reason for this is the technical difficulty in directly measuring CN variation (CNV using molecular methods, and the lack of single nucleotide polymorphisms (SNPs that can tag complex CNV that has arisen multiple times on different SNP haplotypes. One CNV locus implicated in human disease is FCGR. Here we aimed to use next-generation sequencing (NGS data from the 1000 Genomes Project to assign CN at FCGR3A and FCGR3B and to comprehensively assess the ability of SNPs to tag specific CN variants. A read-depth algorithm was developed (CNVrd and validated on a subset of HapMap samples using CN assignments that had previously been determined using molecular and microarray methods. At 7 out of 9 other complex loci there was >90% concordance with microarray data. However, given that some prior knowledge of CN is required, the generalizability of CNVrd is limited and should be applied to other complex CNV loci with caution. Subsequently, CN was assigned et FCGR3B using CNVrd in a total of 952 samples from the 1000 Genomes Project, using three classes and SNPs that correlated with duplication were identified. The best tag SNP was observed in the Mexican-American sample set for duplication at FCGR3B. This SNP (rs117435514, r² = 0.79 also tagged similar duplication in Chinese and Japanese (r² = 0.35-0.60, but not in Caucasian or African. No tag SNP for duplication at FCGR3A or deletion at FCGR3B was identified in any population. We conclude that it is possible to tag CNV at the FCGR locus, but CN and SNPs have to be characterized and correlated on a population-specific basis.

  9. Parallel Evolution of Copy-Number Variation across Continents in Drosophila melanogaster

    Science.gov (United States)

    Schrider, Daniel R.; Hahn, Matthew W.; Begun, David J.

    2016-01-01

    Genetic differentiation across populations that is maintained in the presence of gene flow is a hallmark of spatially varying selection. In Drosophila melanogaster, the latitudinal clines across the eastern coasts of Australia and North America appear to be examples of this type of selection, with recent studies showing that a substantial portion of the D. melanogaster genome exhibits allele frequency differentiation with respect to latitude on both continents. As of yet there has been no genome-wide examination of differentiated copy-number variants (CNVs) in these geographic regions, despite their potential importance for phenotypic variation in Drosophila and other taxa. Here, we present an analysis of geographic variation in CNVs in D. melanogaster. We also present the first genomic analysis of geographic variation for copy-number variation in the sister species, D. simulans, in order to investigate patterns of parallel evolution in these close relatives. In D. melanogaster we find hundreds of CNVs, many of which show parallel patterns of geographic variation on both continents, lending support to the idea that they are influenced by spatially varying selection. These findings support the idea that polymorphic CNVs contribute to local adaptation in D. melanogaster. In contrast, we find very few CNVs in D. simulans that are geographically differentiated in parallel on both continents, consistent with earlier work suggesting that clinal patterns are weaker in this species. PMID:26809315

  10. Dosage sensitivity shapes the evolution of copy-number varied regions.

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    Benjamin Schuster-Böckler

    Full Text Available Dosage sensitivity is an important evolutionary force which impacts on gene dispensability and duplicability. The newly available data on human copy-number variation (CNV allow an analysis of the most recent and ongoing evolution. Provided that heterozygous gene deletions and duplications actually change gene dosage, we expect to observe negative selection against CNVs encompassing dosage sensitive genes. In this study, we make use of several sources of population genetic data to identify selection on structural variations of dosage sensitive genes. We show that CNVs can directly affect expression levels of contained genes. We find that genes encoding members of protein complexes exhibit limited expression variation and overlap significantly with a manually derived set of dosage sensitive genes. We show that complexes and other dosage sensitive genes are underrepresented in CNV regions, with a particular bias against frequent variations and duplications. These results suggest that dosage sensitivity is a significant force of negative selection on regions of copy-number variation.

  11. Association of Copy Number Variations in Autism Spectrum Disorders: A Systematic Review

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    Elif Funda Sener

    2014-01-01

    Full Text Available Autism spectrum disorders (ASDs are characterized by language impairments, social deficits, and repetitive behaviors. The onset of symptoms occurs by the age of 3 and shows a lifelong persistence. Genetics plays a major role in the etiology of ASD. Except genetics, several potential risk factors (environmental factors and epigenetics may contribute to ASD. Copy number variations (CNVs are the most widespread structural variations in the human genome. These variations can alter the genome structure either by deletion or by duplication. CNVs can be de novo or inherited. Chromosomal rearrangements have been detected in 5–10% of the patients with ASD and recently copy number changes ranging from a few kilobases (kb to several megabases (Mb in size have been reported. Recent data have also revealed that submicroscopic CNVs can have a role in ASD, and de novo CNVs seem to be a more common risk factor in sporadic compared with inherited forms of ASD. CNVs are being implicated as a contributor to the pathophysiology of complex neurodevelopmental disorders and they can affect a wide range of human phenotypes including mental retardation (MR, autism, neuropsychiatric disorders, and susceptibility to other complex traits such as HIV, Crohn’s disease, and psoriasis. This review emphasizes the major CNVs reported to date in ASD.

  12. Jagged1 DNA Copy Number Variation Is Associated with Poor Outcome in Liver Cancer.

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    Kawaguchi, Kazunori; Honda, Masao; Yamashita, Taro; Okada, Hikari; Shirasaki, Takayoshi; Nishikawa, Masashi; Nio, Kouki; Arai, Kuniaki; Sakai, Yoshio; Yamashita, Tatsuya; Mizukoshi, Eishiro; Kaneko, Shuichi

    2016-08-01

    Notch signaling abnormalities are reported to be involved in the acceleration of malignancy in solid tumors and stem cell formation or regeneration in various organs. We analyzed specific genes for DNA copy number variations in liver cancer cells and investigated whether these factors relate to clinical outcome. Chromosome 20p, which includes the ligand for Notch pathways, Jagged1, was found to be amplified in several types of hepatoma cells, and its mRNA was up-regulated according to α-fetoprotein gene expression levels. Notch inhibition using Jagged1 shRNA and γ-secretase inhibitors produced significant suppression of cell growth in α-fetoprotein-producing cells with suppression of downstream genes. Using in vivo hepatoma models, the administration of γ-secretase inhibitors resulted in reduced tumor sizes and effective Notch inhibition with widespread apoptosis and necrosis of viable tumor cells. The γ-secretase inhibitors suppressed cell growth of the epithelial cell adhesion molecule-positive fraction in hepatoma cells, indicating that Notch inhibitors could suppress the stem cell features of liver cancer cells. Even in clinical liver cancer samples, the expression of α-fetoprotein and Jagged1 showed significant correlation, and amplification of the copy number of Jagged1 was associated with Jagged1 mRNA expression and poor survival after liver cancer surgical resection. In conclusion, amplification of Jagged1 contributed to mRNA expression that activates the Jagged1-Notch signaling pathway in liver cancer and led to poor outcome.

  13. Copy Number Deletion Has Little Impact on Gene Expression Levels in Racehorses

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    Kyung-Do Park

    2014-09-01</