scholarly journals Combined Analysis of SNP Array Data Identifies Novel CNV Candidates and Pathways in Ependymoma and Mesothelioma

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Gabriel Wajnberg ◽  
Benilton S. Carvalho ◽  
Carlos G. Ferreira ◽  
Fabio Passetti
Keyword(s):  
Open Source ◽  
Open Source Software ◽  
Copy Number ◽  
Chemotherapy Resistance ◽  
Snp Array ◽  
Copy Number Variations ◽  
Genomic Region ◽  
Structural Genomic ◽  
Innovative Strategy ◽  
Novel Strategy

Copy number variation is a class of structural genomic modifications that includes the gain and loss of a specific genomic region, which may include an entire gene. Many studies have used low-resolution techniques to identify regions that are frequently lost or amplified in cancer. Usually, researchers choose to use proprietary or non-open-source software to detect these regions because the graphical interface tends to be easier to use. In this study, we combined two different open-source packages into an innovative strategy to identify novel copy number variations and pathways associated with cancer. We used a mesothelioma and ependymoma published datasets to assess our tool. We detected previously described and novel copy number variations that are associated with cancer chemotherapy resistance. We also identified altered pathways associated with these diseases, like cell adhesion in patients with mesothelioma and negative regulation of glutamatergic synaptic transmission in ependymoma patients. In conclusion, we present a novel strategy using open-source software to identify copy number variations and altered pathways associated with cancer.

scholarly journals Integrating genomic correlation structure improves copy number variations detection

2020 ◽  
Author(s):  
Xizhi Luo ◽  
Fei Qin ◽  
Guoshuai Cai ◽  
Feifei Xiao
Keyword(s):  
Copy Number ◽  
Snp Array ◽  
Copy Number Variations ◽  
Correlation Structure ◽  
Supplementary Information ◽  
Dependence Structure ◽  
Random Pattern ◽  
Genomic Correlation ◽  
Equal Chance ◽  
Cnv Detection

Abstract Motivation Copy number variation plays important roles in human complex diseases. The detection of copy number variants (CNVs) is identifying mean shift in genetic intensities to locate chromosomal breakpoints, the step of which is referred to as chromosomal segmentation. Many segmentation algorithms have been developed with a strong assumption of independent observations in the genetic loci, and they assume each locus has an equal chance to be a breakpoint (i.e. boundary of CNVs). However, this assumption is violated in the genetics perspective due to the existence of correlation among genomic positions, such as linkage disequilibrium (LD). Our study showed that the LD structure is related to the location distribution of CNVs, which indeed presents a non-random pattern on the genome. To generate more accurate CNVs, we proposed a novel algorithm, LDcnv, that models the CNV data with its biological characteristics relating to genetic dependence structure (i.e. LD). Results We theoretically demonstrated the correlation structure of CNV data in SNP array, which further supports the necessity of integrating biological structure in statistical methods for CNV detection. Therefore, we developed the LDcnv that integrated the genomic correlation structure with a local search strategy into statistical modeling of the CNV intensities. To evaluate the performance of LDcnv, we conducted extensive simulations and analyzed large-scale HapMap datasets. We showed that LDcnv presented high accuracy, stability and robustness in CNV detection and higher precision in detecting short CNVs compared to existing methods. This new segmentation algorithm has a wide scope of potential application with data from various high-throughput technology platforms. Availability and implementation https://github.com/FeifeiXiaoUSC/LDcnv. Supplementary information Supplementary data are available at Bioinformatics online.

Frequency of Common Copy-Number Variations at 15q11.2q13 in Sperm of Healthy Men

2019 ◽  
Vol 159 (2) ◽  
pp. 66-73 ◽  
Author(s):  
Takahiro Kinoshita ◽  
Masashi Mikami ◽  
Tadayuki Ayabe ◽  
Keiko Matsubara ◽  
Hiromi Ono ◽  
...  
Keyword(s):  
Copy Number ◽  
Alcohol Intake ◽  
Negative Binomial ◽  
Smoking Status ◽  
Clinical Information ◽  
Estimating Equation ◽  
Copy Number Variations ◽  
Genomic Region ◽  
Healthy Men ◽  
Significant Difference

The genomic region at 15q11.2q13 represents a hotspot for copy-number variations (CNVs) due to nonallelic homologous recombination. Previous studies have suggested that the development of 15q11.2q13 deletions in sperm may be affected by seasonal factors because patients with Prader-Willi syndrome resulting from 15q11.2q13 deletions on paternally derived chromosomes showed autumn-dominant birth seasonality. The present study aimed to determine the frequency of 15q11.2q13 CNVs in sperm of healthy men and clarify the effects of various environmental factors, i.e., age, smoking status, alcohol intake, and season, on the frequency. Thirty volunteers were asked to provide semen samples and clinical information once in each season of a year. The rates of 15q11.2q13 CNVs were examined using 2-color FISH. The results were statistically analyzed using a generalized estimating equation with negative binomial distribution and a log link function. Consequently, informative data were obtained from 83 samples of 26 individuals. The rates of deletions and duplications ranged from 0.04 to 0.48% and from 0.08 to 0.30%, respectively. The rates were not correlated with the age, smoking status, or alcohol intake. Sperm produced in winter showed 1.2 to 1.4-fold high rates for both deletions and duplications as compared with sperm produced in the other seasons; however, there was no significant difference. These results demonstrate high and variable CNV rates at 15q11.2q13 in sperm of healthy men. These CNVs appear to occur independent of the age, smoking status, or alcohol intake, while the effect of season remains inconclusive. Our results merit further validation.

High-Resolution Genomic Profiling of Philadelphia Chromosome-Positive (Ph+) Acute Lymphoblastic Leukaemia (ALL) Identified Novel Recurrent Copy Number Variations Involved in Both Pathogenesis and Resistance to Tyrosine Kinase Inhibitors.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 230-230
Author(s):  
Ilaria Iacobucci ◽  
E. Ottaviani ◽  
A. Astolfi ◽  
S. Soverini ◽  
N. Testoni ◽  
...  
Keyword(s):  
High Resolution ◽  
Copy Number ◽  
Complex Disease ◽  
B Lymphocyte ◽  
Philadelphia Chromosome ◽  
Snp Array ◽  
Copy Number Variations ◽  
Imatinib Resistance ◽  
Copy Number State ◽  
Monosomy 7

Abstract The Ph chromosome is the most frequent cytogenetic aberration associated with ALL and it represents the single most significant adverse prognostic marker. Despite the encouraging results achieved with imatinib, resistance develops rapidly and is quickly followed by disease progression. Some mechanisms of resistance have been widely described but the full knowledge of contributing factors driving both the disease and resistance remains to be defined. In order to identify at submicroscopic level genetic lesions driving leukemogenesis and resistance, we profiled until now the genomes of 18 patients, out of 55 Ph+ ALL patients treated in our institute, at diagnosis (n=11) or at the time of haematological relapse (n=7) during therapy with imatinib or dasatinib. 250 ng of genomic DNA were processed on 500K single nucleotide polymorphism (SNP) array according to protocols provided by the manufacturer (Affymetrix Inc., Santa Clara, CA, USA). The median SNP call rate of analysed samples was 96%. Raw signal data were analyzed by BRLMM algorithm and copy number state was calculated with respect to a set of 48 Hapmap normal individuals and a diploid reference set of samples obtained from acute leukaemia cases in remission. Regions of amplification and deletion were visualized by Integrated Genome Browser and mapped to RefSeq to identify the specific genes involved in the lesion. Our analysis identified multiple copy number alterations per case, with deletions outnumbering amplification almost 3:1. Lesions varied from loss or gain of complete chromosome arms (trisomy 4, monosomy 7, loss of 9p, 10q, 14q, 16q and gain of 1q and 17q) to microdeletions and microduplications targeting genomic intervals. The recurring microdeletions that we detected in at least 50% of patients (both at diagnosis and at relapse) included 1p36.21 (PRAMEF), 3q29 (TFCR), 7p14.1 (AMPH), 8p23 (DEFB105A), 14q11.2 (DAD1), 16p13.11 (PDXDC1, NTAN1, RRN3), 16p11.2 (SNP) and 19p13.2 (CARM1, SMARCA4). A common microamplification was 4q13.2 (TMPRSS11E) and 17q21.31. Some genomic alterations were identified in genes regulating B-lymphocyte differentiation, such as PAX5 (n=3), BLNK (n=1) and VPREB1 (n=6) and in genes with an established role in leukemogenesis, such as MDS, BTG1, MLLT3 and RUNX1. Furthermore, many of the deletions detected included genes encoded for phosphatase proteins (e.g. PTPRD, PPP1R9B, PTPN18) and for zinc-finger proteins without any difference between diagnosis and resistance. It is noteworthy that some lesions felt in regions lacking annotated genes (loss: 2p11.2, 3p12.3, 7q11.21 and 14q32.33; gain: 8q23.3 and 13q21.1). Using high-resolution genome wide approach we showed that Ph+ ALL is a more complex disease characterized by multiple genomic anomalies which may provide new insights into the mechanisms underlying leukemogenesis and may be used as targets for existing or novel drugs. Supported by: European LeukemiaNet, COFIN 2003, Novartis Oncology Clinical Development, AIL.

scholarly journals Clinical Utility and the Yield of Single Nucleotide Polymorphism Array in Prenatal Diagnosis of Fetal Central Nervous System Abnormalities

2021 ◽  
Vol 8 ◽  
Author(s):  
Meiying Cai ◽  
Hailong Huang ◽  
Liangpu Xu ◽  
Na Lin
Keyword(s):  
Central Nervous System ◽  
Single Nucleotide Polymorphism ◽  
Copy Number ◽  
Chromosomal Abnormalities ◽  
Karyotype Analysis ◽  
Snp Array ◽  
Copy Number Variations ◽  
Nucleotide Polymorphism ◽  
Single Nucleotide ◽  
Pathogenic Cnvs

Applying single nucleotide polymorphism (SNP) array to identify the etiology of fetal central nervous system (CNS) abnormality, and exploring its association with chromosomal abnormalities, copy number variations, and obstetrical outcome. 535 fetuses with CNS abnormalities were analyzed using karyotype analysis and SNP array. Among the 535 fetuses with CNS abnormalities, chromosomal abnormalities were detected in 36 (6.7%) of the fetuses, which were consistent with karyotype analysis. Further, additional 41 fetuses with abnormal copy number variations (CNVs) were detected using SNP array (the detection rate of additional abnormal CNVs was 7.7%). The rate of chromosomal abnormalities, but not that of pathogenic CNVs in CNS abnormalities with other ultrasound abnormalities was significantly higher than that in isolated CNS abnormalities. The rates of chromosomal abnormalities and pathogenic CNVs in fetuses with spine malformation (50%), encephalocele (50%), subependymal cyst (20%), and microcephaly (16.7%) were higher than those with other isolated CNS abnormalities. The pregnancies for 36 cases with chromosomal abnormalities, 18 cases with pathogenic CNVs, and three cases with VUS CNVs were terminated. SNP array should be used in the prenatal diagnosis of fetuses with CNS abnormalities, which can enable better prenatal assessment and genetic counseling, and affect obstetrical outcomes.

scholarly journals Evaluation of Chromosomal Abnormalities and Copy Number Variations in Fetuses with Ultrasonic Soft Markers

2020 ◽  
Author(s):  
Meiying Cai ◽  
Na Lin ◽  
Liangpu Xu ◽  
hailong huang
Keyword(s):  
Copy Number ◽  
Chromosomal Abnormalities ◽  
Snp Array ◽  
Copy Number Variations ◽  
Clinical Value ◽  
Obstetrical Outcomes ◽  
Genetic Abnormalities ◽  
Significant Difference ◽  
Snp Array Analysis ◽  
Soft Marker

Abstract Background: Some ultrasonic soft markers can be found during ultrasound examination. However, the etiology of the fetuses with ultrasonic soft markers is still unknown. This study aimed to evaluate the genetic etiology and clinical value of chromosomal abnormalities and copy number variations (CNVs) in fetuses with ultrasonic soft markers.Methods: Among 1131 fetuses, 729 had single ultrasonic soft marker, 322 had two ultrasonic soft markers, and 80 had three or more ultrasonic soft markers. All fetuses underwent conventional karyotyping, followed by single nucleotide polymorphism (SNP) array analysis. Results: Among 1131 fetuses with ultrasonic soft markers, 46 had chromosomal abnormalities. In addition to the 46 fetuses with chromosomal abnormalities consistent with the results of the karyotyping analysis, the SNP array identified additional 6.1% (69/1131) abnormal CNVs. The rate of abnormal CNVs in fetuses with ultrasonic soft marker, two ultrasonic soft markers, three or more ultrasonic soft markers were 6.2%, 6.2%, and 5.0%, respectively. No significant difference was found in the rate of abnormal CNVs among the groups.Conclusions: Genetic abnormalities affect obstetrical outcomes. The SNP array can fully complement conventional karyotyping in fetuses with ultrasonic soft markers, improve detection rate of chromosomal abnormalities, and affect obstetrical outcomes.

scholarly journals Patients with polyclonal hepatocellular carcinoma are at a high risk of early recurrence and have a poor recurrence-free survival period

2021 ◽  
Author(s):  
Masaki Kaibori ◽  
Kazuko Sakai ◽  
Hideyuki Matsushima ◽  
Hisashi Kosaka ◽  
Kosuke Matsui ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
High Risk ◽  
Copy Number ◽  
Snp Array ◽  
Early Recurrence ◽  
Copy Number Variations ◽  
Survival Period ◽  
Recurrence Free Survival ◽  
Free Survival ◽  
A Genome

Abstract Background/purpose of the study Tumor heterogeneity based on copy number variations is associated with the evolution of cancer and its clinical grade. Clonal composition (CC) represents the number of clones based on the distribution of B-allele frequency (BAF) obtained from a genome-wide single nucleotide polymorphism (SNP) array. A higher CC number represents a high degree of heterogeneity. We hypothesized and evaluated that the CC number in hepatocellular carcinoma (HCC) tissues might be associated with the clinical outcomes of patients. Methods Somatic mutation, whole transcriptome, and copy number variations of 36 frozen tissue samples of operably resected HCC tissues by targeted deepsequencing, RNAseq and SNP array. Results The samples were classified the heterogeneous tumors as poly-CC (n = 26) and the homogeneous tumors as mono-CC (n = 8). The patients with poly-CC had a higher rate of early recurrence and a significantly shorter recurrence-free survival period than the mono-CC patients (7.0 vs. not reached, p = 0.0084). No differences in pathogenic non-synonymous mutations, such as TP53, were observed between the two groups when targeted deep sequencing was applied. A transcriptome analysis showed that cell cycle-related pathways were enriched in the poly-CC tumors, compared with the mono-CC tumors. poly-CC HCC is highly proliferative and has a high risk of early recurrence. Conclusion CC is a candidate biomarker for predicting the risk of early postoperative recurrence and warrants further investigation.

scholarly journals Frequency of the STRC-CATSPER2 deletion in STRC-associated hearing loss patients

2022 ◽  
Vol 12 (1) ◽  
Author(s):  
Shin-ya Nishio ◽  
Shin-ichi Usami
Keyword(s):  
Hearing Loss ◽  
Male Infertility ◽  
Genetic Counselling ◽  
Copy Number ◽  
Read Depth ◽  
Copy Number Variations ◽  
Genomic Region ◽  
High Prevalence ◽  
Homozygous Deletions ◽  
Next Generation Sequencing Ngs

AbstractThe STRC gene, located on chromosome 15q15.3, is one of the genetic causes of autosomal recessive mild-to-moderate sensorineural hearing loss. One of the unique characteristics of STRC-associated hearing loss is the high prevalence of long deletions or copy number variations observed on chromosome 15q15.3. Further, the deletion of chromosome 15q15.3 from STRC to CATSPER2 is also known to be a genetic cause of deafness infertility syndrome (DIS), which is associated with not only hearing loss but also male infertility, as CATSPER2 plays crucial roles in sperm motility. Thus, information regarding the deletion range for each patient is important to the provision of appropriate genetic counselling for hearing loss and male infertility. In the present study, we performed next-generation sequencing (NGS) analysis for 9956 Japanese hearing loss patients and analyzed copy number variations in the STRC gene based on NGS read depth data. In addition, we performed Multiplex Ligation-dependent Probe Amplification analysis to determine the deletion range including the PPIP5K1, CKMT1B, STRC and CATSPER2 genomic region to estimate the prevalence of the STRC-CATSPER deletion, which is causative for DIS among the STRC-associated hearing loss patients. As a result, we identified 276 cases with STRC-associated hearing loss. The prevalence of STRC-associated hearing loss in Japanese hearing loss patients was 2.77% (276/9956). In addition, 77.1% of cases with STRC homozygous deletions carried a two copy loss of the entire CKMT1B-STRC-CATSPER2 gene region. This information will be useful for the provision of more appropriate genetic counselling regarding hearing loss and male infertility for the patients with a STRC deletion.

scholarly journals Copy number variation analysis in Chinese children with complete atrioventricular canal and single ventricle

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Xingyu Zhang ◽  
Bo Wang ◽  
Guoling You ◽  
Ying Xiang ◽  
Qihua Fu ◽  
...  
Keyword(s):  
Copy Number ◽  
Trisomy 21 ◽  
Single Ventricle ◽  
Snp Array ◽  
Copy Number Variations ◽  
Chinese Children ◽  
Atrioventricular Canal ◽  
Genome Wide ◽  
Number Variation ◽  
Complete Atrioventricular

Abstract Background Congenital heart disease (CHD) is one of the most common birth defects. Copy number variations (CNVs) have been proved to be important genetic factors that contribute to CHD. Here we screened genome-wide CNVs in Chinese children with complete atrioventricular canal (CAVC) and single ventricle (SV), since there were scarce researches dedicated to these two types of CHD. Methods We screened CNVs in 262 sporadic CAVC cases and 259 sporadic SV cases respectively, using a customized SNP array. The detected CNVs were annotated and filtered using available databases. Results Among 262 CAVC patients, we identified 6 potentially-causative CNVs in 43 individuals (16.41%, 43/262), including 2 syndrome-related CNVs (7q11.23 and 8q24.3 deletion). Surprisingly, 90.70% CAVC patients with detected CNVs (39/43) were found to carry duplications of 21q11.2–21q22.3, which were recognized as trisomy 21 (Down syndrome, DS). In CAVC with DS patients, the female to male ratio was 1.6:1.0 (24:15), and the rate of pulmonary hypertension (PH) was 41.03% (16/39). Additionally, 6 potentially-causative CNVs were identified in the SV patients (2.32%, 6/259), and none of them was trisomy 21. Most CNVs identified in our cohort were classified as rare (< 1%), occurring just once among CAVC or SV individuals except the 21q11.2–21q22.3 duplication (14.89%) in CAVC cohort. Conclusions Our study identified 12 potentially-causative CNVs in 262 CAVC and 259 SV patients, representing the largest cohort of these two CHD types in Chinese population. The results provided strong correlation between CAVC and DS, which also showed sex difference and high incidence of PH. The presence of potentially-causative CNVs suggests the etiology of complex CHD is incredibly diverse, and CHD candidate genes remain to be discovered.

scholarly journals Interactive analysis and quality assessment of single-cell copy-number variations

2014 ◽  
Author(s):  
Tyler Garvin ◽  
Robert Aboukhalil ◽  
Jude Kendall ◽  
Timour Baslan ◽  
Gurinder S. Atwal ◽  
...  
Keyword(s):  
Quality Assessment ◽  
Single Cell ◽  
Open Source ◽  
Visual Analytics ◽  
Copy Number ◽  
Phylogenetic Trees ◽  
Copy Number Variations ◽  
Copy Number Alterations ◽  
Interactive Analysis ◽  
Web Platform

We present an open-source visual-analytics web platform, Ginkgo (http://qb.cshl.edu/ginkgo), for the interactive analysis and quality assessment of single-cell copy-number alterations. Ginkgo automatically constructs copy-number profiles of individual cells from mapped reads, as well as constructing phylogenetic trees of related cells. We validate Ginkgo by reproducing the results of five major studies and examine the data characteristics of three commonly used single-cell amplification techniques to conclude DOP-PCR to be the most consistent for CNV analysis.

scholarly journals Patients with polyclonal hepatocellular carcinoma are at a high risk of early recurrence and have a poor recurrence-free survival period

2022 ◽  
Author(s):  
Masaki Kaibori ◽  
Kazuko Sakai ◽  
Hideyuki Matsushima ◽  
Hisashi Kosaka ◽  
Kosuke Matsui ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
High Risk ◽  
Deep Sequencing ◽  
Copy Number ◽  
Snp Array ◽  
Early Recurrence ◽  
Copy Number Variations ◽  
Recurrence Free Survival ◽  
Free Survival ◽  
Targeted Deep Sequencing

Abstract Background/purpose of the study Tumor heterogeneity based on copy number variations is associated with the evolution of cancer and its clinical grade. Clonal composition (CC) represents the number of clones based on the distribution of B-allele frequency (BAF) obtained from a genome-wide single nucleotide polymorphism (SNP) array. A higher CC number represents a high degree of heterogeneity. We hypothesized and evaluated that the CC number in hepatocellular carcinoma (HCC) tissues might be associated with the clinical outcomes of patients. Methods Somatic mutation, whole transcriptome, and CC number based on copy number variations of 36 frozen tissue samples of operably resected HCC tissues were analyzed by targeted deep sequencing, transcriptome analysis, and SNP array. Results The samples were classified into the heterogeneous tumors as poly-CC (n = 26) and the homogeneous tumors as mono-CC (n = 8). The patients with poly-CC had a higher rate of early recurrence and a significantly shorter recurrence-free survival period than the mono-CC patients (7.0 months vs. not reached, p = 0.0084). No differences in pathogenic non-synonymous mutations, such as TP53, were observed between the two groups when targeted deep sequencing was applied. A transcriptome analysis showed that cell cycle-related pathways were enriched in the poly-CC tumors, compared to the mono-CC tumors. Poly-CC HCC is highly proliferative and has a high risk of early recurrence. Conclusion CC is a possible candidate biomarker for predicting the risk of early postoperative recurrence and warrants further investigation.

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