scholarly journals Somatic Structural Alterations in Childhood Leukemia Can Be Backtracked in Neonatal Dried Blood Spots by Use of Whole-Genome Sequencing and Digital PCR

2019 ◽  
Vol 65 (2) ◽  
pp. 345-347
Author(s):  
Fulya Taylan ◽  
Benedicte Bang ◽  
Ingegerd Ivanov Öfverholm ◽  
Anh-Nhi Tran ◽  
Mats Heyman ◽  
...  
2020 ◽  
Author(s):  
Noam Teyssier ◽  
Anna Chen ◽  
Elias Duarte ◽  
Rene Sit ◽  
Bryan Greenhouse ◽  
...  

Abstract Background: Whole-genome sequencing (WGS) is becoming increasingly useful to study the biology, epidemiology, and ecology of malaria parasites. Despite ease of sampling, DNA extracted from dried blood spots (DBS) has a high ratio of human DNA compared to parasite DNA, which poses a challenge for downstream genetic analyses. We evaluated the effects of multiple methods for DNA extraction, digestion of methylated DNA, and amplification on the quality and fidelity of WGS data recovered from DBS. Results: At 100 parasites/μL, Chelex-Tween-McrBC samples had higher coverage (5X depth = 93% genome) than QIAamp extracted samples (5X depth = 76% genome). The two evaluated sWGA primer sets showed minor differences in overall genome coverage and SNP concordance, with a newly proposed combination of 20 primers showing a modest improvement in coverage over those previously published. Conclusions: Overall, Tween-Chelex extracted samples that were treated with McrBC digestion and are amplified using 6A10AD sWGA conditions had minimal dropout rate, higher percentages of coverage at higher depth, and more accurate SNP concordance than QiaAMP extracted samples. These findings extend the results of previously reported methods, making whole genome sequencing accessible to a larger number of low density samples that are commonly encountered in cross-sectional surveys. Keywords: Malaria, P. falciparum, dried blood spots, Tween-Chelex, McrBC, selective whole genome amplification, whole genome sequencing This work was supported by the Bill & Melinda Gates Foundation, Grant Number OPP1132226 This work was supported by the Bill & Melinda Gates Foundation, Grant Number OPP1132226


2016 ◽  
Vol 15 (1) ◽  
Author(s):  
Samuel O. Oyola ◽  
Cristina V. Ariani ◽  
William L. Hamilton ◽  
Mihir Kekre ◽  
Lucas N. Amenga-Etego ◽  
...  

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Pooja Agrawal ◽  
Shanmukh Katragadda ◽  
Arun K. Hariharan ◽  
Vijayashree Gauribidanur Raghavendrachar ◽  
Arunika Agarwal ◽  
...  

Abstract Background Dried blood spots (DBS) are a relatively inexpensive source of nucleic acids and are easy to collect, transport, and store in large-scale field surveys, especially in resource-limited settings. However, their performance in whole-genome sequencing (WGS) relative to that of venous blood DNA has not been analyzed for various downstream applications. Methods This study compares the WGS performance of DBS paired with venous blood samples collected from 12 subjects. Results Results of standard quality checks of coverage, base quality, and mapping quality were found to be near identical between DBS and venous blood. Concordance for single-nucleotide variants, insertions and deletions, and copy number variants was high between these two sample types. Additionally, downstream analyses typical of population-based studies were performed, such as mitochondrial heteroplasmy detection, haplotype analysis, mitochondrial copy number changes, and determination of telomere lengths. The absolute mitochondrial copy number values were higher for DBS than for venous blood, though the trend in sample-to-sample variation was similar between DBS and blood. Telomere length estimates in most DBS samples were on par with those from venous blood. Conclusion DBS samples can serve as a robust and feasible alternative to venous blood for studies requiring WGS analysis.


2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Noam B. Teyssier ◽  
Anna Chen ◽  
Elias M. Duarte ◽  
Rene Sit ◽  
Bryan Greenhouse ◽  
...  

Abstract Background Whole-genome sequencing (WGS) is becoming increasingly useful to study the biology, epidemiology, and ecology of malaria parasites. Despite ease of sampling, DNA extracted from dried blood spots (DBS) has a high ratio of human DNA compared to parasite DNA, which poses a challenge for downstream genetic analyses. The effects of multiple methods for DNA extraction, digestion of methylated DNA, and amplification were evaluated on the quality and fidelity of WGS data recovered from DBS. Methods Low parasite density mock DBS samples were created, extracted either with Tween-Chelex or QIAamp, treated with or without McrBC, and amplified with one of three different amplification techniques (two sWGA primer sets and one rWGA). Extraction conditions were evaluated on performance of sequencing depth, percentiles of coverage, and expected SNP concordance. Results At 100 parasites/μL, Chelex-Tween-McrBC samples had higher coverage (5 × depth = 93% genome) than QIAamp extracted samples (5 × depth = 76% genome). The two evaluated sWGA primer sets showed minor differences in overall genome coverage and SNP concordance, with a newly proposed combination of 20 primers showing a modest improvement in coverage over those previously published. Conclusions Overall, Tween-Chelex extracted samples that were treated with McrBC digestion and are amplified using 6A10AD sWGA conditions had minimal dropout rate, higher percentages of coverage at higher depth, and more accurate SNP concordance than QiaAMP extracted samples. These findings extend the results of previously reported methods, making whole genome sequencing accessible to a larger number of low density samples that are commonly encountered in cross-sectional surveys.


2021 ◽  
Author(s):  
Noam Teyssier ◽  
Anna Chen ◽  
Elias Duarte ◽  
Rene Sit ◽  
Bryan Greenhouse ◽  
...  

Abstract Background: Whole-genome sequencing (WGS) is becoming increasingly useful to study the biology, epidemiology, and ecology of malaria parasites. Despite ease of sampling, DNA extracted from dried blood spots (DBS) has a high ratio of human DNA compared to parasite DNA, which poses a challenge for downstream genetic analyses. We evaluated the effects of multiple methods for DNA extraction, digestion of methylated DNA, and amplification on the quality and fidelity of WGS data recovered from DBS.Results: At 100 parasites/μL, Chelex-Tween-McrBC samples had higher coverage (5X depth = 93% genome) than QIAamp extracted samples (5X depth = 76% genome). The two evaluated sWGA primer sets showed minor differences in overall genome coverage and SNP concordance, with a newly proposed combination of 20 primers showing a modest improvement in coverage over those previously published. Conclusions: Overall, Tween-Chelex extracted samples that were treated with McrBC digestion and are amplified using 6A10AD sWGA conditions had minimal dropout rate, higher percentages of coverage at higher depth, and more accurate SNP concordance than QiaAMP extracted samples. These findings extend the results of previously reported methods, making whole genome sequencing accessible to a larger number of low density samples that are commonly encountered in cross-sectional surveys.


Haematologica ◽  
2017 ◽  
Vol 102 (5) ◽  
pp. e179-e183 ◽  
Author(s):  
Christoph Bartenhagen ◽  
Ute Fischer ◽  
Klaus Korn ◽  
Stefan M. Pfister ◽  
Michael Gombert ◽  
...  

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Daniele Merico ◽  
Yehonatan Pasternak ◽  
Mehdi Zarrei ◽  
Edward J. Higginbotham ◽  
Bhooma Thiruvahindrapuram ◽  
...  

AbstractIn more than one-third of primary immunodeficiency (PID) patients, extensive genetic analysis including whole-exome sequencing (WES) fails to identify the genetic defect. Whole-genome sequencing (WGS) is able to detect variants missed by other genomics platforms, enabling the molecular diagnosis of otherwise unresolved cases. Here, we report two siblings, offspring of consanguineous parents, who experienced similar severe events encompassing early onset of colitis, lymphoproliferation, and hypogammaglobulinemia, typical of lipopolysaccharide-responsive and beige-like anchor (LRBA) or cytotoxic T lymphocyte antigen 4 (CTLA4) deficiencies. Gene-panel sequencing, comparative genomic hybridization (CGH) array, and WES failed to reveal a genetic aberration in relevant genes. WGS of these patients detected a 12.3 kb homozygous tandem duplication that was absent in control cohorts and is predicted to disrupt the reading frame of the LRBA gene. The variant was validated by PCR and Sanger sequencing, demonstrating the presence of the junction between the reference and the tandem-duplicated sequence. Droplet digital PCR (ddPCR) further confirmed the copy number in the unaffected parents (CN = 3, heterozygous) and affected siblings (CN = 4, homozygous), confirming the expected segregation pattern. In cases of suspected inherited immunodeficiency, WGS may reveal a mutation when other methods such as microarray and WES analysis failed to detect an aberration.


2021 ◽  
Author(s):  
Noam Teyssier ◽  
Anna Chen ◽  
Elias Duarte ◽  
Rene Sit ◽  
Bryan Greenhouse ◽  
...  

Abstract Background Whole-genome sequencing (WGS) is becoming increasingly useful to study the biology, epidemiology, and ecology of malaria parasites. Despite ease of sampling, DNA extracted from dried blood spots (DBS) has a high ratio of human DNA compared to parasite DNA, which poses a challenge for downstream genetic analyses. The effects of multiple methods for DNA extraction, digestion of methylated DNA, and amplification were evaluated on the quality and fidelity of WGS data recovered from DBS.MethodsLow parasite density mock DBS samples were created, extracted either with Tween-Chelex or QIAamp, treated with or without McrBC, and amplified with one of three different amplification techniques (two sWGA primer sets and one rWGA). Extraction conditions were evaluated on performance of sequencing depth, percentiles of coverage, and expected SNP concordance.ResultsAt 100 parasites/μL, Chelex-Tween-McrBC samples had higher coverage (5X depth = 93% genome) than QIAamp extracted samples (5X depth = 76% genome). The two evaluated sWGA primer sets showed minor differences in overall genome coverage and SNP concordance, with a newly proposed combination of 20 primers showing a modest improvement in coverage over those previously published.ConclusionsOverall, Tween-Chelex extracted samples that were treated with McrBC digestion and are amplified using 6A10AD sWGA conditions had minimal dropout rate, higher percentages of coverage at higher depth, and more accurate SNP concordance than QiaAMP extracted samples. These findings extend the results of previously reported methods, making whole genome sequencing accessible to a larger number of low density samples that are commonly encountered in cross-sectional surveys.


Sign in / Sign up

Export Citation Format

Share Document