Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
37,988
result(s) for
"genomic variation"
Sort by:
How to design a national genomic project—a systematic review of active projects
by
Kovanda, Anja
,
Zimani, Ana Nyasha
,
Peterlin, Borut
in
Age composition
,
Archives & records
,
Bioinformatics
2021
An increasing number of countries are investing efforts to exploit the human genome, in order to improve genetic diagnostics and to pave the way for the integration of precision medicine into health systems. The expected benefits include improved understanding of normal and pathological genomic variation, shorter time-to-diagnosis, cost-effective diagnostics, targeted prevention and treatment, and research advances.
We review the 41 currently active individual national projects concerning their aims and scope, the number and age structure of included subjects, funding, data sharing goals and methods, and linkage with biobanks, medical data, and non-medical data (exposome). The main aims of ongoing projects were to determine normal genomic variation (90%), determine pathological genomic variation (rare disease, complex diseases, cancer, etc.) (71%), improve infrastructure (59%), and enable personalized medicine (37%). Numbers of subjects to be sequenced ranges substantially, from a hundred to over a million, representing in some cases a significant portion of the population. Approximately half of the projects report public funding, with the rest having various mixed or private funding arrangements. 90% of projects report data sharing (public, academic, and/or commercial with various levels of access) and plan on linking genomic data and medical data (78%), existing biobanks (44%), and/or non-medical data (24%) as the basis for enabling personal/precision medicine in the future.
Our results show substantial diversity in the analysed categories of 41 ongoing national projects. The overview of current designs will hopefully inform national initiatives in designing new genomic projects and contribute to standardisation and international collaboration.
Journal Article
k-mer-based GWAS reveals a candidate avirulence gene and structural variation in Puccinia triticina linked to gain of Lr20 virulence
by
Tsushima, Ayako
,
Morier-Gxoyiya, Césarée
,
Wilderspin, Sarah
in
Analysis
,
Animal Genetics and Genomics
,
Anopheles
2025
Background
Plant pathogens secrete effector proteins into their hosts to promote colonisation. Among these are avirulence (Avr) effectors, which can be recognised by specific host immune receptors, triggering an immune response that prevents pathogen progression. This recognition exerts strong evolutionary pressure on pathogens to alter and/or eliminate
Avr
genes to escape recognition. Consequently, understanding
Avr
gene evolution is critical for developing effective resistance deployment strategies. However, identifying and validating Avr effectors remains a significant challenge, especially for fungal plant pathogens, leading to a limited catalogue of
Avr
genes. This challenge is particularly pronounced for obligate biotrophic pathogens such as the wheat leaf (brown) rust fungus
Puccinia triticina
(
Pt
), where only two
Avr
genes have been confirmed to date.
Results
In this study, we conducted a
k
-mer-based genome-wide association study (GWAS) to detect a broad spectrum of structural genetic variations — including single nucleotide polymorphisms (SNPs), insertions and deletions (indels) and copy number variations (CNVs) — that may contribute to the gain of virulence in
Pt
. Analysis of
k
-mers linked to avirulence phenotypes of
Pt
isolates across eleven leaf rust resistance (
Lr
) loci, revealed a distinct association peak on chromosome 10B corresponding to avirulence against
Lr20
. Assembly of the associated
k
-mers produced a 50 bp sequence that was located near two candidate effector genes, one of which — termed
Pt76_024702
— also displayed high levels of expression during both early and later stages of infection. Furthermore, the genomic region harbouring
Pt76_024702
exhibited large-scale deletions in certain
Pt
lineages virulent to
Lr20
, particularly those infecting durum wheat (
Triticum turgidum
ssp.
durum
).
Conclusion
These findings highlight
Pt76_024702
as a compelling candidate for
AvrLr20
and demonstrate the significant potential of the presented
k-
mer-based GWAS approach to enhance the
Avr
gene catalogue. This strategy is particularly promising for complex fungal pathogens such as the notorious wheat rust pathogens where conventional approaches have previously proved challenging.
Journal Article
Genotyping structural variants in pangenome graphs using the vg toolkit
by
Heller, David
,
Eizenga, Jordan
,
Dawson, Eric T.
in
Accuracy
,
Animal Genetics and Genomics
,
Bioinformatics
2020
Structural variants (SVs) remain challenging to represent and study relative to point mutations despite their demonstrated importance. We show that variation graphs, as implemented in the vg toolkit, provide an effective means for leveraging SV catalogs for short-read SV genotyping experiments. We benchmark vg against state-of-the-art SV genotypers using three sequence-resolved SV catalogs generated by recent long-read sequencing studies. In addition, we use assemblies from 12 yeast strains to show that graphs constructed directly from aligned de novo assemblies improve genotyping compared to graphs built from intermediate SV catalogs in the VCF format.
Journal Article
Subgroup-specific structural variation across 1,000 medulloblastoma genomes
by
Carlotti, Carlos G.
,
Eberhart, Charles G.
,
Ellison, David W.
in
631/208/68
,
631/208/726/649/2157
,
631/67/1922
2012
Medulloblastoma, the most common malignant paediatric brain tumour, is currently treated with nonspecific cytotoxic therapies including surgery, whole-brain radiation, and aggressive chemotherapy. As medulloblastoma exhibits marked intertumoural heterogeneity, with at least four distinct molecular variants, previous attempts to identify targets for therapy have been underpowered because of small samples sizes. Here we report somatic copy number aberrations (SCNAs) in 1,087 unique medulloblastomas. SCNAs are common in medulloblastoma, and are predominantly subgroup-enriched. The most common region of focal copy number gain is a tandem duplication of
SNCAIP
, a gene associated with Parkinson’s disease, which is exquisitely restricted to Group 4α. Recurrent translocations of
PVT1
, including
PVT1-MYC
and
PVT1-NDRG1
, that arise through chromothripsis are restricted to Group 3. Numerous targetable SCNAs, including recurrent events targeting TGF-β signalling in Group 3, and NF-κB signalling in Group 4, suggest future avenues for rational, targeted therapy.
Medulloblastoma is the most common malignant brain tumour in children; having assembled over 1,000 samples the authors report that somatic copy number aberrations are common in medulloblastoma, in particular a tandem duplication of
SNCAIP
, a gene associated with Parkinson’s disease, which is restricted to subgroup 4α, and translocations of
PVT1
, which are restricted to Group 3.
The medulloblastoma genome dissected
Medulloblastoma is the most common malignant brain tumour in children. Four papers published in the 2 August 2012 issue of
Nature
use whole-genome and other sequencing techniques to produce a detailed picture of the genetics and genomics of this condition. Notable findings include the identification of recurrent mutations in genes not previously implicated in medulloblastoma, with significant genetic differences associated with the four biologically distinct subgroups and clinical outcomes in each. Potential avenues for therapy are suggested by the identification of targetable somatic copy-number alterations, including recurrent events targeting TGFβ signalling in Group 3, and NF-κB signalling in Group 4 medulloblastomas.
Journal Article
Integrative detection and analysis of structural variation in cancer genomes
2018
Structural variants (SVs) can contribute to oncogenesis through a variety of mechanisms. Despite their importance, the identification of SVs in cancer genomes remains challenging. Here, we present a framework that integrates optical mapping, high-throughput chromosome conformation capture (Hi-C), and whole-genome sequencing to systematically detect SVs in a variety of normal or cancer samples and cell lines. We identify the unique strengths of each method and demonstrate that only integrative approaches can comprehensively identify SVs in the genome. By combining Hi-C and optical mapping, we resolve complex SVs and phase multiple SV events to a single haplotype. Furthermore, we observe widespread structural variation events affecting the functions of noncoding sequences, including the deletion of distal regulatory sequences, alteration of DNA replication timing, and the creation of novel three-dimensional chromatin structural domains. Our results indicate that noncoding SVs may be underappreciated mutational drivers in cancer genomes.
The authors present an integrative framework for identifying structural variants (SVs) in cancer that applies optical mapping, Hi-C, and whole-genome sequencing. They find SVs affecting distal regulatory sequences, DNA replication, and three-dimensional chromatin structure.
Journal Article
SVvalidation: A long-read-based validation method for genomic structural variation
2024
Although various methods have been developed to detect structural variations (SVs) in genomic sequences, few are used to validate these results. Several commonly used SV callers produce many false positive SVs, and existing validation methods are not accurate enough. Therefore, a highly efficient and accurate validation method is essential. In response, we propose SVvalidation—a new method that uses long-read sequencing data for validating SVs with higher accuracy and efficiency. Compared to existing methods, SVvalidation performs better in validating SVs in repeat regions and can determine the homozygosity or heterozygosity of an SV. Additionally, SVvalidation offers the highest recall, precision, and F1-score (improving by 7-16%) across all datasets. Moreover, SVvalidation is suitable for different types of SVs. The program is available at https://github.com/nwpuzhengyan/SVvalidation .
Journal Article
Hidden biases in germline structural variant detection
by
Carroll, Andrew
,
Pan, Bohu
,
Sedlazeck, Fritz J.
in
Animal Genetics and Genomics
,
Base Sequence
,
Bias
2021
Background
Genomic structural variations (SV) are important determinants of genotypic and phenotypic changes in many organisms. However, the detection of SV from next-generation sequencing data remains challenging.
Results
In this study, DNA from a Chinese family quartet is sequenced at three different sequencing centers in triplicate. A total of 288 derivative data sets are generated utilizing different analysis pipelines and compared to identify sources of analytical variability. Mapping methods provide the major contribution to variability, followed by sequencing centers and replicates. Interestingly, SV supported by only one center or replicate often represent true positives with 47.02% and 45.44% overlapping the long-read SV call set, respectively. This is consistent with an overall higher false negative rate for SV calling in centers and replicates compared to mappers (15.72%). Finally, we observe that the SV calling variability also persists in a genotyping approach, indicating the impact of the underlying sequencing and preparation approaches.
Conclusions
This study provides the first detailed insights into the sources of variability in SV identification from next-generation sequencing and highlights remaining challenges in SV calling for large cohorts. We further give recommendations on how to reduce SV calling variability and the choice of alignment methodology.
Journal Article
Performance evaluation of structural variation detection using DNBSEQ whole-genome sequencing
by
Liang, Xinming
,
Rao, Junhua
,
Peng, Lihua
in
Algorithms
,
Analysis
,
Animal Genetics and Genomics
2025
Background
DNBSEQ platforms have been widely used for variation detection, including single-nucleotide variants (SNVs) and short insertions and deletions (INDELs), which is comparable to Illumina. However, the performance and even characteristics of structural variations (SVs) detection using DNBSEQ platforms are still unclear.
Results
In this study, we assessed the detection of SVs using 40 tools on eight DNBSEQ whole-genome sequencing (WGS) datasets and two Illumina WGS datasets of NA12878. Our findings confirmed that the performance of SVs detection using the same tool on DNBSEQ and Illumina datasets was highly consistent, with correlations greater than 0.80 on metrics of number, size, precision and sensitivity, respectively. Furthermore, we constructed a “DNBSEQ” SV set (4,785 SVs) from the DNBSEQ datasets and an “Illumina” SV set (6,797 SVs) from the Illumina datasets. We found that these two SV sets were highly consistent of SV sites and genomic characteristics, including repetitive regions, GC distribution, difficult-to-sequence regions, and gene features, indicating the robustness of our comparative analysis and highlights the value of both platforms in understanding the genomic context of SVs.
Conclusions
Our study systematically analyzed and characterized germline SVs detected on WGS datasets sequenced from DNBSEQ platforms, providing a benchmark resource for further studies of SVs using DNBSEQ platforms.
Journal Article
PSVRP: a pig structural variant reference panel for complex trait genomics and precision breeding
by
Quan, Yu
,
Wang, Sicong
,
Liu, Wansheng
in
Animal breeding
,
Animal genetics
,
Animal Genetics and Genomics
2025
Background
Pigs are not only a key source of animal protein worldwide, but also serve as important models in biological research. With the rapid development of short- and long-read sequencing technologies, genetic studies in pigs have advanced considerably. Although extensive research has been conducted on single-nucleotide polymorphisms (SNPs) and small insertions/deletions (indels), which has provided important insights into pig domestication, evolution, and trait formation, structural variants (SVs) remain underexplored due to technical limitations in sequencing resolution, challenges in variant detection, and insufficient population-scale sampling.
Results
In this study, we constructed the Pig Structural Variant Reference Panel (PSVRP) by integrating 21 long-read and 1,193 short-read whole-genome resequencing datasets from globally diverse pig populations. A total of 319,058 high-confidence SVs were identified, comprising 196,620 insertions and 122,438 deletions. Phylogenetic and ADMIXTURE analyses revealed clear divergence between Asian and European pigs, consistent with results derived from SNPs and indels data. Selection scans highlighted candidate genes associated with key traits, such as
EPAS1
and
NOVA1
for high-altitude adaptation, and
PLAG1
and
MIB1
for body size regulation.
Conclusions
The PSVRP provides a high-resolution, population-scale pig SVs genotyping resource. This comprehensive panel deepens our understanding of genetic variation, facilitates the discovery of functional variants underlying adaptive and economic traits, and offers new insights for precision pig breeding.
Journal Article
Whole-genome sequencing reveals complex structural variations at a major locus linked to pigmented spot sizes in Tianfu goats
by
Huang, Qingsi
,
Li, Li
,
Xiang, Qiunan
in
Animal genetics
,
Animal Genetics and Genomics
,
Animals
2025
Background
Coat color is one of the most easily recognizable appearance traits used to discriminate livestock breeds and individuals. This study investigated the genetic loci and candidate genes affecting pigmented spots in Tianfu (TF) goats.
Results
The pigmented spot scores in 96 TF goats ranged from 0.20 to 3.95. Whole-genome sequencing identified 15,132,291 bi-allelic autosomal SNPs in these animals. Linear mixed-model analyses identified a major locus near the
EDNRA
gene on chromosome 17 and a second strong association signal on chromosome 4. Annotation of short variants within the major locus revealed no apparent causal mutations. Further analysis of short-read data revealed a complex genomic rearrangement spanning ~ 1.1 Mb in TF goats, primarily comprising one inverted duplication, one direct duplication, and two deletion events. These structural variations (SVs) were validated using PacBio HiFi sequencing data from Boer goats, one of the parental breeds of TF goats. Among the SVs, an 83,630-bp inverted duplication approximately 80 kb upstream of
EDNRA
showed the strongest association with the phenotype, as demonstrated by a univariate model in which this duplication explained 30.99% of the phenotypic variation. In silico analysis revealed that this duplication contains putative binding sites for pigmentation-related transcription factors, including
MITF
and
PAX3
. Furthermore, this inverted duplication, combined with the lead SNP on chromosome 4, accounted for 55.79% of the phenotypic variation.
Conclusion
We identified a genomic region with complex SVs near
EDNRA
on chromosome 17 as a major locus influencing pigmented spot sizes in TF goats. We further pinpointed the causal mutations to an approximately 80-kb inverted duplication. Additionally, we detected a strong secondary association signal on chromosome 4. Our findings deepen the understanding of genetic variations underlying pigmentation in goats and provide valuable insights for selective breeding and conservation efforts.
Journal Article