scholarly journals Novel signals of adaptive genetic variation in northwestern Atlantic cod revealed by whole‐genome sequencing

2019 ◽  
Vol 12 (10) ◽  
pp. 1971-1987 ◽  
Author(s):  
Gemma V. Clucas ◽  
R. Nicolas Lou ◽  
Nina O. Therkildsen ◽  
Adrienne I. Kovach
Keyword(s):  
Genetic Variation ◽  
Whole Genome Sequencing ◽  
Genome Sequencing ◽  
Atlantic Cod ◽  
Whole Genome ◽  
Adaptive Genetic Variation

Advancing RNA Virus Discovery and Biology with Whole Genome Sequencing

2021 ◽  
Author(s):  
◽  
Mariah Taylor ◽  
Keyword(s):  
Genetic Variation ◽  
Amino Acid ◽  
Whole Genome Sequencing ◽  
Genome Sequencing ◽  
Rna Virus ◽  
Animal Health ◽  
Functional Domains ◽  
Whole Genome ◽  
Coding Region

Two RNA virus families that pose a threat to human and animal health are Hantaviridae and Coronaviridae. These RNA viruses which originate in wildlife continue and will continue to cause disease, and hence, it is critical that scientific research define the mechanisms as to how these viruses spillover and adapt to new hosts to become endemic. One gap in our ability to define these mechanisms is the lack of whole genome sequences for many of these viruses. To address this specific gap, I developed a versatile amplicon-based whole-genome sequencing (WGS) approach to identify viral genomes of hantaviruses and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) within reservoir and spillover hosts. In my research studies, I used the amplicon-based WGS approach to define the genetic plasticity of viral RNA within pathogenic and nonpathogenic hantavirus species. The standing genetic variation of Andes orthohantavirus and Prospect Hill orthohantavirus was mapped out and amino acid changes occurring outside of functional domains were identified within the nucleocapsid and glycoprotein. I observed several amino acid changes in functional domains of the RNA-dependent RNA polymerase, as well as single nucleotide polymorphisms (SNPs) within the 3’ non-coding region (NCR) of the S-segment. To identify whether virus adaptation would occur within the S- and L-segments we attempted to adapt hantaviruses in vitro in a spillover host model through passaging experiments. In early passages we identified few mutations in the M-segment with the majority being identified in the S-segment 3’ NCR and the L-segment. This work suggests that hantavirus adaptation occurs in the S- and L-segments although the effect of these mutants on pathology is yet to be determined. While sequencing laboratory isolates is easily accomplished, sequencing low concentrations of virus within the reservoir is a formidable task. I further translated our amplicon-based WGS approach into a pan-oligonucleotide amplicon-based WGS approach to sequence hantavirus vRNA and mRNA from reservoir and spillover hosts in Ukraine. This approach successfully identified a novel Puumala orthohantavirus (PUUV) strain in Ukraine and using Bayesian phylogenetics we found this strain to be associated with the PUUV Latvian lineage. Early during the SARS-CoV-2 pandemic, I applied the knowledge gained in the hantavirus WGS efforts to sequencing of SARS-CoV-2 from nasopharyngeal swabs collected in April 2020. The genetic diversity of 45 SARS-CoV-2 isolates was evaluated with the methods I developed. We identified D614G, a notable mutation known for increasing transmission, in over 90% of our isolates. Two major lineages distinguish SARS-CoV-2 variants worldwide, lineages A and B. While most of our isolates were found within B lineage, we also identified one isolate within lineage A. We performed in vitro work which confirmed A lineage isolates as having poor replication in the trachea as compared to the nasal cavity. Five of these isolates presented a unique array of mutations which were assessed in the keratin 18 human angiotensin-converting enzyme 2 (K18-hACE2) mouse model for its response immunologically and pathogenically. We identified a distinction of pathogenesis between the A and B lineages with emphysema being common amongst A lineage isolates. Additionally, we discovered a small cohort of likely SNPs that defined the late induction of eosinophils during infection. In summary, this work will further define the dynamics of genetic variation and plasticity within virus populations that cause disease outbreaks and will allow a deeper understanding of the virus-host relationship.

scholarly journals Whole-genome sequencing uncovers cryptic and hybrid species among Atlantic and Pacific cod-fish

2015 ◽  
Author(s):  
Katrín Halldórsdóttir ◽  
Einar Árnason
Keyword(s):  
Whole Genome Sequencing ◽  
Genome Sequencing ◽  
Atlantic Cod ◽  
Walleye Pollock ◽  
Evolutionary Status ◽  
Whole Genome ◽  
Hybrid Speciation ◽  
Hybrid Species ◽  
The Pacific ◽  
Starting Point

Speciation often involves the splitting of a lineage and the adaptation of daughter lineages to different environments. It may also involve the merging of divergent lineages, thus creating a stable homoploid hybrid species1that constructs a new ecological niche by transgressing2the ecology of the parental types. Hybrid speciation may also contribute to enigmatic and cryptic biodiversity in the sea.3,4The enigmatic walleye pollock, which is not a pollock at all but an Atlantic cod that invaded the Pacific 3.8 Mya,5differs considerably from its presumed closest relatives, the Pacific and Atlantic cod. Among the Atlantic cod, shallow-water coastal and deep-water migratory frontal ecotypes are associated with highly divergent genomic islands;6,7however, intermediates remain an enigma.8Here, we performed whole-genome sequencing of over 200 individuals using up to 33 million SNPs based on genotype likelihoods9and showed that the evolutionary status of walleye pollock is a hybrid species: it is a hybrid between Arctic cod and Atlantic cod that transgresses the ecology of its parents. For the first time, we provide decisive evidence that the Atlantic cod coastal and frontal ecotypes are separate species that hybridized, leading to a true-breeding hybrid species that differs ecologically from its parents. We refute monophyly and dichotomous branching of these taxa, and stress the importance of looking beyond branching trees at admixture and hybridity. Our study demonstrates the power of whole-genome sequencing and population genomics in providing deep insights into fundamental processes of speciation. Our study was a starting point for further work aimed at examining the criteria of hybrid speciation,10selection, sterility and structural chromosomal variation11among cod-fish, which are among the most important fish stocks in the world. The hybrid nature of both the walleye pollock and Atlantic cod raises the question concerning the extent to which very profitable fisheries12,13depend on hybrid vigour. Our results have implications for management of marine resources in times of rapid climate change.14,15

scholarly journals Analyses of X-linked and autosomal genetic variation in population-scale whole genome sequencing

2011 ◽  
Vol 43 (8) ◽  
pp. 741-743 ◽  
Author(s):  
Srikanth Gottipati ◽  
Leonardo Arbiza ◽  
Adam Siepel ◽  
Andrew G Clark ◽  
Alon Keinan
Keyword(s):  
Genetic Variation ◽  
Whole Genome Sequencing ◽  
Genome Sequencing ◽  
Whole Genome ◽  
Population Scale

scholarly journals Whole-genome sequencing for an enhanced understanding of genetic variation among South Africans

2017 ◽  
Vol 8 (1) ◽  
Author(s):  
Ananyo Choudhury ◽  
Michèle Ramsay ◽  
Scott Hazelhurst ◽  
Shaun Aron ◽  
Soraya Bardien ◽  
...  
Keyword(s):  
Genetic Variation ◽  
Whole Genome Sequencing ◽  
Genome Sequencing ◽  
Whole Genome ◽  
South Africans

scholarly journals Corrigendum and follow-up: Whole genome sequencing of multiple CRISPR-edited mouse lines suggests no excess mutations

2017 ◽  
Author(s):  
Kellie A. Schaefer ◽  
Benjamin W Darbro ◽  
Diana F. Colgan ◽  
Stephen H. Tsang ◽  
Alexander G. Bassuk ◽  
...  
Keyword(s):  
Genetic Variation ◽  
Whole Genome Sequencing ◽  
Genome Sequencing ◽  
Whole Genome ◽  
Mouse Line ◽  
Genome Data ◽  
Parental Lines ◽  
Mouse Lines

Our previous publication suggested CRISPR-Cas9 editing at the zygotic stage might unexpectedly introduce a multitude of subtle but unintended mutations, an interpretation that not surprisingly raised numerous questions. The key issue is that since parental lines were not available, might the reported variants have been inherited? To expand upon the limited available whole genome data on whether CRISPR-edited mice show more genetic variation, whole-genome sequencing was performed on two other mouse lines that had undergone a CRISPR-editing procedure. Again, parents were not available for either the Capn5 nor Fblim1 CRISPR-edited mouse lines, so strain controls were examined. Additionally, we also include verification of variants detected in the initial mouse line. Taken together, these whole-genome-sequencing-level results support the idea that in specific cases, CRISPR-Cas9 editing can precisely edit the genome at the organismal level and may not introduce numerous, unintended, off-target mutations.

scholarly journals Mid-pass whole genome sequencing enables biomedical genetic studies of diverse populations

BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Anne-Katrin Emde ◽  
Amanda Phipps-Green ◽  
Murray Cadzow ◽  
C. Scott Gallagher ◽  
Tanya J. Major ◽  
...  
Keyword(s):  
Genetic Variation ◽  
Whole Genome Sequencing ◽  
Genome Sequencing ◽  
Whole Genome ◽  
Diverse Populations ◽  
Human Genetic Variation ◽  
Underrepresented Populations ◽  
Financial Barriers ◽  
Genetic Studies ◽  
Disease Relevance

Abstract Background Historically, geneticists have relied on genotyping arrays and imputation to study human genetic variation. However, an underrepresentation of diverse populations has resulted in arrays that poorly capture global genetic variation, and a lack of reference panels. This has contributed to deepening global health disparities. Whole genome sequencing (WGS) better captures genetic variation but remains prohibitively expensive. Thus, we explored WGS at “mid-pass” 1-7x coverage. Results Here, we developed and benchmarked methods for mid-pass sequencing. When applied to a population without an existing genomic reference panel, 4x mid-pass performed consistently well across ethnicities, with high recall (98%) and precision (97.5%). Conclusion Compared to array data imputed into 1000 Genomes, mid-pass performed better across all metrics and identified novel population-specific variants with potential disease relevance. We hope our work will reduce financial barriers for geneticists from underrepresented populations to characterize their genomes prior to biomedical genetic applications.

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