scholarly journals Copy number heterogeneity, large origin tandem repeats, and interspecies recombination in HHV-6A and HHV-6B reference strains

2017 ◽  
Author(s):  
Alexander L. Greninger ◽  
Pavitra Roychoudhury ◽  
Negar Makhsous ◽  
Derek Hanson ◽  
Jill Chase ◽  
...  
Keyword(s):  
Next Generation Sequencing ◽  
Reference Materials ◽  
Copy Number ◽  
Tandem Repeats ◽  
The Body ◽  
Origin Of Replication ◽  
Next Generation ◽  
Interspecies Recombination ◽  
Reference Strains ◽  
Generation Sequencing

AbstractQuantitative PCR is the diagnostic pillar for clinical virology testing, and reference materials are necessary for accurate, comparable quantitation between clinical laboratories. Accurate quantitation of HHV-6 is important for detection of viral reactivation and inherited chromosomally integrated HHV-6 in immunocompromised patients. Reference materials in clinical virology commonly consist of laboratory-adapted viral strains that may be affected by the culture process. We performed next-generation sequencing to make relative copy number measurements at single nucleotide resolution of eight candidate HHV-6A and seven HHV-6B reference strains and DNA materials from the HHV-6 Foundation and Advanced Biotechnologies. 11 of 17 (65%) HHV6 candidate reference materials showed multiple copies of the origin of replication upstream of the U41 gene by next-generation sequencing. These large tandem repeats arose independently in culture-adapted HHV-6A and HHV-6B strains, measuring 1254 bp and 983 bp, respectively. Copy number measured between 4-10X copies relative to the rest of the genome. We also report the first interspecies recombinant HHV-6 strain with a HHV-6A GS backbone and >5.5kb region from HHV-6B Z29 from U41-U43 that covered the origin tandem repeat. Specific HHV-6A reference strains demonstrated duplication of regions at UL1/UL2, U87, and U89, as well as deletion in the U12-U24 region and U94/95 genes. HHV-6 strains derived from cord blood mononuclear cells from different labs on different continents revealed no copy number differences throughout the viral genome. These data indicate large origin tandem duplications are an adaptation of both HHV-6A and HHV-6B in culture and show interspecies recombination is possible within theBetaherpesvirinae.ImportanceAnything in science that needs to be quantitated requires a standard unit of measurement. This includes viruses, for which quantitation increasingly determines definitions of pathology and guidelines for treatment. However, the act of making standard or reference material in virology can alter its very usefulness through genomic duplications, insertions, and rearrangements. We used deep sequencing to examine candidate reference strains for HHV-6, a ubiquitous human virus that can reactivate in the immunocompromised population and is integrated into the human genome in every cell of the body for 1% of people worldwide. We found large tandem repeats in the origin of replication for both HHV-6A and HHV-6B that are selected for in culture. We also found the first interspecies recombinant between HHV-6A and HHV-6B, a phenomenon that is well-known in alphaherpesviruses but to date has not been seen in betaherpesviruses. These data critically inform HHV-6 biology and the standard selection process.

scholarly journals Copy Number Heterogeneity, Large Origin Tandem Repeats, and Interspecies Recombination in Human Herpesvirus 6A (HHV-6A) and HHV-6B Reference Strains

2018 ◽  
Vol 92 (10) ◽  
Author(s):  
Alexander L. Greninger ◽  
Pavitra Roychoudhury ◽  
Negar Makhsous ◽  
Derek Hanson ◽  
Jill Chase ◽  
...  
Keyword(s):  
Next Generation Sequencing ◽  
Reference Materials ◽  
Copy Number ◽  
Tandem Repeats ◽  
Human Herpesvirus ◽  
Origin Of Replication ◽  
Next Generation ◽  
Interspecies Recombination ◽  
Reference Strains ◽  
Generation Sequencing

ABSTRACTQuantitative PCR is a diagnostic pillar for clinical virology testing, and reference materials are necessary for accurate, comparable quantitation between clinical laboratories. Accurate quantitation of human herpesvirus 6A/B (HHV-6A/B) is important for detection of viral reactivation and inherited chromosomally integrated HHV-6A/B in immunocompromised patients. Reference materials in clinical virology commonly consist of laboratory-adapted viral strains that may be affected by the culture process. We performed next-generation sequencing to make relative copy number measurements at single nucleotide resolution of eight candidate HHV-6A and seven HHV-6B reference strains and DNA materials from the HHV-6 Foundation and Advanced Biotechnologies Inc. Eleven of 17 (65%) HHV-6A/B candidate reference materials showed multiple copies of the origin of replication upstream of the U41 gene by next-generation sequencing. These large tandem repeats arose independently in culture-adapted HHV-6A and HHV-6B strains, measuring 1,254 bp and 983 bp, respectively. The average copy number measured was between 5 and 10 times the number of copies of the rest of the genome. We also report the first interspecies recombinant HHV-6A/B strain with a HHV-6A backbone and a >5.5-kb region from HHV-6B, from U41 to U43, that covered the origin tandem repeat. Specific HHV-6A reference strains demonstrated duplication of regions at U1/U2, U87, and U89, as well as deletion in the U12-to-U24 region and the U94/U95 genes. HHV-6A/B strains derived from cord blood mononuclear cells from different laboratories on different continents with fewer passages revealed no copy number differences throughout the viral genome. These data indicate that large origin tandem duplications are an adaptation of both HHV-6A and HHV-6B in culture and show interspecies recombination is possible within theBetaherpesvirinae.IMPORTANCEAnything in science that needs to be quantitated requires a standard unit of measurement. This includes viruses, for which quantitation increasingly determines definitions of pathology and guidelines for treatment. However, the act of making standard or reference material in virology can alter its very accuracy through genomic duplications, insertions, and rearrangements. We used deep sequencing to examine candidate reference strains for HHV-6, a ubiquitous human virus that can reactivate in the immunocompromised population and is integrated into the human genome in every cell of the body for 1% of people worldwide. We found large tandem repeats in the origin of replication for both HHV-6A and HHV-6B that are selected for in culture. We also found the first interspecies recombinant between HHV-6A and HHV-6B, a phenomenon that is well known in alphaherpesviruses but to date has not been seen in betaherpesviruses. These data critically inform HHV-6A/B biology and the standard selection process.

scholarly journals Next-Generation Sequencing–Based Assessment of JAK2, PD-L1, and PD-L2 Copy Number Alterations at 9p24.1 in Breast Cancer

2019 ◽  
Vol 21 (2) ◽  
pp. 307-317 ◽  
Author(s):  
Sounak Gupta ◽  
Chad M. Vanderbilt ◽  
Paolo Cotzia ◽  
Javier A. Arias-Stella ◽  
Jason C. Chang ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Next Generation Sequencing ◽  
Copy Number ◽  
Copy Number Alterations ◽  
Next Generation ◽  
Generation Sequencing

scholarly journals Use of next-generation sequencing to detectLDLRgene copy number variation in familial hypercholesterolemia

2017 ◽  
Vol 58 (11) ◽  
pp. 2202-2209 ◽  
Author(s):  
Michael A. Iacocca ◽  
Jian Wang ◽  
Jacqueline S. Dron ◽  
John F. Robinson ◽  
Adam D. McIntyre ◽  
...  
Keyword(s):  
Next Generation Sequencing ◽  
Copy Number Variation ◽  
Familial Hypercholesterolemia ◽  
Copy Number ◽  
Next Generation ◽  
Number Variation ◽  
Generation Sequencing

scholarly journals Genome-wide characterization of copy number variations in the host genome in genetic resistance to Marek's disease using next generation sequencing

2020 ◽  
Author(s):  
Hao Bai ◽  
Yanghua He ◽  
Yi Ding ◽  
Huanmin Zhang ◽  
Jilan Chen ◽  
...  
Keyword(s):  
Next Generation Sequencing ◽  
Copy Number ◽  
Marek's Disease ◽  
Neoplastic Disease ◽  
Marek’S Disease ◽  
Next Generation ◽  
Qrt Pcr ◽  
Genome Wide ◽  
A Genome ◽  
Generation Sequencing

Abstract Background: Marek’s disease (MD) is a highly neoplastic disease primarily affecting chickens, and remains as a chronic infectious disease that threatens the poultry industry. Copy number variation (CNV) has been examined in many species and is recognized as a major source of genetic variation that directly contributes to phenotypic variation such as resistance to infectious diseases. Two highly inbred chicken lines 63 (MD-resistant) and 72 (MD-susceptible), as well as their F1 generation and six recombinant congenic strains (RCSs) with varied susceptibility to MD, are considered as ideal models to identify the complex mechanisms of genetic and molecular resistance to MD.Results: In the present study, to unravel the potential genetic mechanisms underlying resistance to MD, we performed a genome-wide CNV detection using next generation sequencing on the inbred chicken lines with the assistance of CNVnator. As a result, a total of 1,649 CNV regions (CNVRs) were successfully identified after merging all the nine datasets, of which 90 CNVRs were overlapped across all the chicken lines. Within these shared regions, 1,360 harbored genes were identified. In addition, 55 and 44 CNVRs with 62 and 57 harbored genes were specifically identified in line 63 and 72, respectively. Bioinformatics analysis showed that the nearby genes were significantly enriched in 36 GO terms and 6 KEGG pathways including JAK/STAT signaling pathway. Ten CNVRs (nine deletions and one duplication) involved in 10 disease-related genes were selected for validation by using qRT-PCR, all of which were successfully confirmed. Finally, qRT-PCR was also used to validate two deletion events in line 72 that were definitely normal in line 63. One high-confidence gene, IRF2 was identified as the most promising candidate gene underlying resistance and susceptibility to MD in view of its function and overlaps with data from previous study.Conclusions: Our findings provide valuable insights for understanding the genetic mechanism of resistance to MD and the identified gene and pathway could be considered as the subject of further functional characterization.

scholarly journals Comprehensive Assessment of Somatic Copy Number Variation Calling Using Next-Generation Sequencing Data

2021 ◽  
Author(s):  
Yun-Ching Chen ◽  
Fayaz Seifuddin ◽  
Cu Nguyen ◽  
Zhaowei Yang ◽  
Wanqiu Chen ◽  
...  
Keyword(s):  
Next Generation Sequencing ◽  
Copy Number Variation ◽  
Cancer Progression ◽  
Copy Number ◽  
Tissue Sample ◽  
Next Generation Sequencing Data ◽  
Next Generation ◽  
Dna Amount ◽  
Number Variation ◽  
Generation Sequencing

AbstractCopy number variation (CNV) is a common type of mutation that often drives cancer progression. With advances in next-generation sequencing (NGS), CNVs can be detected in a detailed manner via newly developed computational tools but quality of such CNV calls has not been carefully evaluated. We analyzed CNV calls reported by 6 cutting-edge callers for 91 samples which were derived from the same cancer cell line, prepared and sequenced by varying the following factors: type of tissue sample (Fresh vs. Formalin Fixed Paraffin Embedded (FFPE)), library DNA amount, tumor purity, sequencing platform (Whole-Genome Sequencing (WGS) versus Whole-Exome Sequencing (WES)), and sequencing coverage. We found that callers greatly determined the pattern of CNV calls. Calling quality was drastically impaired by low purity (<50%) and became variable when WES, FFPE, and medium purity (50%-75%) were applied. Effects of low DNA amount and low coverage were relatively minor. Our analysis demonstrates the limitation of benchmarking somatic CNV callers when the real ground truth is not available. Our comprehensive analysis has further characterized each caller with respect to confounding factors and examined the consistency of CNV calls, thereby providing guidelines for conducting somatic CNV analysis.

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