Large-scale Genome Sequencing Research Articles

Strategies to Uplift Novel Mendelian Gene Discovery for Improved Clinical Outcomes.

Rare genetic disorders, while individually rare, are collectively common. They represent some of the most severe disorders affecting patients worldwide with significant morbidity and mortality. Over the last decade, advances in genomic methods have significantly uplifted diagnostic rates for patients and facilitated novel and targeted therapies. However, many patients with rare genetic disorders still remain undiagnosed as the genetic etiology of only a proportion of Mendelian conditions has been discovered to date. This article explores existing strategies to identify novel Mendelian genes and how these discoveries impact clinical care and therapeutics. We discuss the importance of data sharing, phenotype-driven approaches, patient-led approaches, utilization of large-scale genomic sequencing projects, constraint-based methods, integration of multi-omics data, and gene-to-patient methods. We further consider the health economic advantages of novel gene discovery and speculate on potential future methods for improved clinical outcomes.

Applying frequency chaos game representation with perceptual image hashing to gene sequence phylogenetic analyses

As a very important research direction in the field of bioinformatics, sequence alignment plays a vital role in the research and development of biology. Converting genome sequence to graph by using frequency chaos game representation (FCGR) is an excellent gene sequence mapping technology, which can store rich genetic information into FCGR graphics. To each FCGR image, we construct its perceptual image hashing (PIH) matrix using the bicubic interpolation zooming. The difference of the perceptual hash matrix of each two images is calculated, and the clustering distance of the corresponding two gene sequences is represented by the differentials of the perceptual hash matrix. In this paper, we aligned and analyzed several typical genome sequence datasets including mammalian mitochondrial genes, human immunodeficiency virus 1 (HIV-1) and hepatitis E virus (HEV) to build their evolutionary trees. Experimental results showed that our PIH combining FCGR method (FCGR-PIH) has similar classification accuracy to the classical Clustal W sequence alignment method. Furthermore, 25 complete mitochondrial DNA sequences of cichlid fishes and 27 Escherichia coli/Shigella full genome sequences were selected from the AFproject test platform for tests. The performance benchmark rankings demonstrate the effectiveness of the FCGR-PIH algorithm and its potential for large-scale genome sequence analysis.

Analysis and Interpretation of the Impact of Missense Variants in Cancer.

Large scale genome sequencing allowed the identification of a massive number of genetic variations, whose impact on human health is still unknown. In this review we analyze, by an in silico-based strategy, the impact of missense variants on cancer-related genes, whose effect on protein stability and function was experimentally determined. We collected a set of 164 variants from 11 proteins to analyze the impact of missense mutations at structural and functional levels, and to assess the performance of state-of-the-art methods (FoldX and Meta-SNP) for predicting protein stability change and pathogenicity. The result of our analysis shows that a combination of experimental data on protein stability and in silico pathogenicity predictions allowed the identification of a subset of variants with a high probability of having a deleterious phenotypic effect, as confirmed by the significant enrichment of the subset in variants annotated in the COSMIC database as putative cancer-driving variants. Our analysis suggests that the integration of experimental and computational approaches may contribute to evaluate the risk for complex disorders and develop more effective treatment strategies.

A vertebrate adaptive radiation is assembled from an ancient and disjunct spatiotemporal landscape

To investigate the origins and stages of vertebrate adaptive radiation, we reconstructed the spatial and temporal histories of adaptive alleles underlying major phenotypic axes of diversification from the genomes of 202 Caribbean pupfishes. On a single Bahamian island, ancient standing variation from disjunct geographic sources was reassembled into new combinations under strong directional selection for adaptation to the novel trophic niches of scale-eating and molluscivory. We found evidence for two longstanding hypotheses of adaptive radiation: hybrid swarm origins and temporal stages of adaptation. Using a combination of population genomics, transcriptomics, and genome-wide association mapping, we demonstrate that this microendemic adaptive radiation of novel trophic specialists on San Salvador Island, Bahamas experienced twice as much adaptive introgression as generalist populations on neighboring islands and that adaptive divergence occurred in stages. First, standing regulatory variation in genes associated with feeding behavior (prlh, cfap20, and rmi1) were swept to fixation by selection, then standing regulatory variation in genes associated with craniofacial and muscular development (itga5, ext1, cyp26b1, and galr2) and finally the only de novo nonsynonymous substitution in an osteogenic transcription factor and oncogene (twist1) swept to fixation most recently. Our results demonstrate how ancient alleles maintained in distinct environmental refugia can be assembled into new adaptive combinations and provide a framework for reconstructing the spatiotemporal landscape of adaptation and speciation.

Genomic landscape of hepatocarcinogenesis.

Hepatocellular carcinoma (HCC) is a global health issue and the fourth leading cause of cancer deaths worldwide. Large-scale HCC genome sequencing analyses have identified core drivers (TERT, TP53, and CTNNB1/AXIN1) as initial molecular events, and other low-frequent drivers that include therapeutically targetable ones. The recent genetic analysis uncovered a distinctive driver gene landscape in precancerous lesions, arguing a discontinuous process at early HCC development. In advanced tumors, intra-tumoral heterogeneity through clonal evolution processes is common, and it displays clear geographic segregation genetically and epigenetically. Diverse epidemiological risk factors for HCC mirrors heterogeneous mutational processes among patient cohorts with distinctive ethnicity, environmental exposures, and lifestyles. The genetic information of individual tumors has been utilized for optimizing treatments, early diagnosis, and monitoring recurrence. It will expand the opportunity for screening high-risk populations, thereby preventing hepatocarcinogenesis in the near future.

Large-scale sequencing of flatfish genomes provides insights into the polyphyletic origin of their specialized body plan

The evolutionary and genetic origins of the specialized body plan of flatfish are largely unclear. We analyzed the genomes of 11 flatfish species representing 9 of the 14 Pleuronectiforme families and conclude that Pleuronectoidei and Psettodoidei do not form a monophyletic group, suggesting independent origins from different percoid ancestors. Genomic and transcriptomic data indicate that genes related to WNT and retinoic acid pathways, hampered musculature and reduced lipids might have functioned in the evolution of the specialized body plan of Pleuronectoidei. Evolution of Psettodoidei involved similar but not identical genes. Our work provides valuable resources and insights for understanding the genetic origins of the unusual body plan of flatfishes.

Methicillin-resistant Staphylococcus pseudintermedius synthesizes deoxyadenosine to cause persistent infection

ABSTRACT Methicillin-resistant Staphylococcus pseudintermedius (MRSP) is an emerging zoonotic pathogen of canine origin that causes an array of fatal diseases, including bacteremia and endocarditis. Despite large-scale genome sequencing projects have gained substantial insights into the genomic landscape of MRSP, current knowledge on virulence determinants that contribute to S. pseudintermedius pathogenesis during human or canine infection is very limited. Using a panel of genetically engineered MRSP variants and a mouse abscess model, we here identified the major secreted nuclease of S. pseudintermedius designated NucB and adenosine synthase A (AdsA) as two synergistically acting enzymes required for MRSP pathogenesis. Similar to Staphylococcus aureus, S. pseudintermedius requires nuclease secretion along with the activity of AdsA to degrade mammalian DNA for subsequent biosynthesis of cytotoxic deoxyadenosine. In this manner, S. pseudintermedius selectively kills macrophages during abscess formation thereby antagonizing crucial host immune cell responses. Ultimately, bioinformatics analyses revealed that NucB and AdsA are widespread in the global S. pseudintermedius population. Together, these data suggest that S. pseudintermedius deploys the canonical Nuc/AdsA pathway to persist during invasive disease and may aid in the development of new therapeutic strategies to combat infections caused by MRSP.

The functional GRHL3-filaggrin axis maintains a tumor differentiation potential and influences drug sensitivity

Current therapies for treating heterogeneous cancers such as head and neck squamous cell carcinoma (HNSCC) are non-selective and are administered independent of response biomarkers. Therapy resistance subsequently emerges, resulting in increased cellular proliferation that is associated with loss of differentiation. Whether a cancer cell differentiation potential can dictate therapy responsiveness is still currently unknown. A multi-omic approach integrating whole-genome and whole-transcriptome sequencing with drug sensitivity was employed in a HNSCC mouse model, primary patients’ data, and human cell lines to assess the potential of functional differentiation in predicting therapy response. Interestingly, a subset of HNSCC with effective GRHL3-dependent differentiation was the most sensitive to inhibitors of PI3K/mTOR, c-Myc, and STAT3 signaling. Furthermore, we identified the GRHL3-differentiation target gene Filaggrin (FLG) as a response biomarker and more importantly, stratified HNSCC subsets as treatment resistant based on their FLG mutational profile. The loss of FLG in sensitive HNSCC resulted in a dramatic resistance to targeted therapies while the GRHL3-FLG signature predicted a favorable patient prognosis. This study provides evidence for a functional GRHL3-FLG tumor-specific differentiation axis that regulates targeted therapy response in HNSCC and establishes a rationale for clinical investigation of differentiation-paired targeted therapy in heterogeneous cancers.

Large-scale sequencing of SARS-CoV-2 genomes from one region allows detailed epidemiology and enables local outbreak management.

The COVID-19 pandemic has spread rapidly throughout the world. In the UK, the initial peak was in April 2020; in the county of Norfolk (UK) and surrounding areas, which has a stable, low-density population, over 3200 cases were reported between March and August 2020. As part of the activities of the national COVID-19 Genomics Consortium (COG-UK) we undertook whole genome sequencing of the SARS-CoV-2 genomes present in positive clinical samples from the Norfolk region. These samples were collected by four major hospitals, multiple minor hospitals, care facilities and community organizations within Norfolk and surrounding areas. We combined clinical metadata with the sequencing data from regional SARS-CoV-2 genomes to understand the origins, genetic variation, transmission and expansion (spread) of the virus within the region and provide context nationally. Data were fed back into the national effort for pandemic management, whilst simultaneously being used to assist local outbreak analyses. Overall, 1565 positive samples (172 per 100 000 population) from 1376 cases were evaluated; for 140 cases between two and six samples were available providing longitudinal data. This represented 42.6 % of all positive samples identified by hospital testing in the region and encompassed those with clinical need, and health and care workers and their families. In total, 1035 cases had genome sequences of sufficient quality to provide phylogenetic lineages. These genomes belonged to 26 distinct global lineages, indicating that there were multiple separate introductions into the region. Furthermore, 100 genetically distinct UK lineages were detected demonstrating local evolution, at a rate of ~2 SNPs per month, and multiple co-occurring lineages as the pandemic progressed. Our analysis: identified a discrete sublineage associated with six care facilities; found no evidence of reinfection in longitudinal samples; ruled out a nosocomial outbreak; identified 16 lineages in key workers which were not in patients, indicating infection control measures were effective; and found the D614G spike protein mutation which is linked to increased transmissibility dominates the samples and rapidly confirmed relatedness of cases in an outbreak at a food processing facility. The large-scale genome sequencing of SARS-CoV-2-positive samples has provided valuable additional data for public health epidemiology in the Norfolk region, and will continue to help identify and untangle hidden transmission chains as the pandemic evolves.

Genomic Alterations of Dermatofibrosarcoma Protuberans Revealed by Whole Genome Sequencing

Background: Dermatofibrosarcoma protuberans (DFSP) is a rare and marginal cutaneous sarcoma between benign and malignant, whose genomic landscape of remains unclear. Methods: In this study, the comprehensive genomic features with 53 tumor-normal pairs of DFSP were revealed by the whole genome sequencing. Real-Time PCR was performed to validate the CNV, immunohistochemistry (IHC) was performed to examine the target protein expression in clinical samples and Sanger sequencing was performed to verify the fusion gene. Findings: The mutational signature 1 (C>T mutation at CpG dinucleotides) is featured in DFSP, resulting in higher mutations in DNA replication. Interestingly, the recurrence of the DFSP is correlated to low TMB. Novel mutation genes in DFSP were identified, including Muc4,6, KMT2C, BRCA1, and subsequently, three molecular sub-types of DFSPs were classified on the basis of Muc4 and Muc6 mutations. Various structural aberrations including genomic rearrangements were identified in DSFPs, particular in 17q and 22q, which cause oncogenes amplification (AKT1, SPHK1, COL1A1, PDGFβ) or tumor suppressors deletion (CDKN2A,B). Importantly, in addition to the reported gene fusion of COL1A1-PDGFβ (t(17;22)) in DFSP, we identified a novel gene fusion SLC2A5-BTBD7(t(1;14)) through our whole-genome sequencing, and verified it experimentally. Enrichment analysis of altered molecules revealed that DNA repair, cell cycle, PI3K and JAK pathways were primarily involved in DFSP. Interpretation: This is the first large-scale whole genome sequencing for DFSP, and our findings demonstrated the comprehensive genomic landscape that highlights the molecular complexity and genomic aberrations of DFSP and provides novel potential diagnostic and therapeutic targets for this disease. Funding Statement: This work was supported by the National Natural Science Foundation of China (81620108024, 82073458, 81974476, 81830096,), Shanghai Municipal Health Commission, and Collaborative Innovation Cluster Project (No. 2019CXJQ02), overseas Expertise Introduction Project for Discipline Innovation (111 Project, No. B20017). Declaration of Interests: The authors declare no conflict of interest. Ethics Approval Statement: All the samples were mainly collected from the Department of Dermatology, The Third Affiliated Hospital, Sun Yat-sen University, and the sampling procedure was approved by the Medical Ethics Committee of The Third Affiliated Hospital, Sun Yat-sen University(protocol number: [2018]02-254-01), and written informed consent from each patient was obtained.

Comparison of different sequencing strategies for assembling chromosome-level genomes of extremophiles with variable GC content

SummaryIn this study, six bacterial isolates with variable GC, including Escherichia coli as mesophilic reference strain, were selected to compare hybrid assembly strategies based on next-generation sequencing (NGS) of short reads, single-tube long-fragment reads (stLFR) sequencing, and Oxford Nanopore Technologies (ONT) sequencing platforms. We obtained the complete genomes using the hybrid assembler Unicycler based on the NGS and ONT reads; others were de novo assembled using NGS, stLFR, and ONT reads by using different strategies. The contiguity, accuracy, completeness, sequencing costs, and DNA material requirements of the investigated strategies were compared systematically. Although all sequencing data could be assembled into accurate whole-genome sequences, the stLFR sequencing data yield a scaffold with more contiguity with more completeness of gene function than NGS sequencing assemblies. Our research provides a low-cost chromosome-level genome assembly strategy for large-scale sequencing of extremophile genomes with different GC contents.

Predicting transcription factor binding sites using DNA shape features based on shared hybrid deep learning architecture

The study of transcriptional regulation is still difficult yet fundamental in molecular biology research. Recent research has shown that the double helix structure of nucleotides plays an important role in improving the accuracy and interpretability of transcription factor binding sites (TFBSs). Although several computational methods have been designed to take both DNA sequence and DNA shape features into consideration simultaneously, how to design an efficient model is still an intractable topic. In this paper, we proposed a hybrid convolutional recurrent neural network (CNN/RNN) architecture, CRPTS, to predict TFBSs by combining DNA sequence and DNA shape features. The novelty of our proposed method relies on three critical aspects: (1) the application of a shared hybrid CNN and RNN has the ability to efficiently extract features from large-scale genomic sequences obtained by high-throughput technology; (2) the common patterns were found from DNA sequences and their corresponding DNA shape features; (3) our proposed CRPTS can capture local structural information of DNA sequences without completely relying on DNA shape data. A series of comprehensive experiments on 66 in vitro datasets derived from universal protein binding microarrays (uPBMs) shows that our proposed method CRPTS obviously outperforms the state-of-the-art methods.

Decoding Genetics of Congenital Heart Disease Using Patient-Derived Induced Pluripotent Stem Cells (iPSCs).

Congenital heart disease (CHD) is the most common cause of infant death associated with birth defects. Recent next-generation genome sequencing has uncovered novel genetic etiologies of CHD, from inherited and de novo variants to non-coding genetic variants. The next phase of understanding the genetic contributors of CHD will be the functional illustration and validation of this genome sequencing data in cellular and animal model systems. Human induced pluripotent stem cells (iPSCs) have opened up new horizons to investigate genetic mechanisms of CHD using clinically relevant and patient-specific cardiac cells such as cardiomyocytes, endothelial/endocardial cells, cardiac fibroblasts and vascular smooth muscle cells. Using cutting-edge CRISPR/Cas9 genome editing tools, a given genetic variant can be corrected in diseased iPSCs and introduced to healthy iPSCs to define the pathogenicity of the variant and molecular basis of CHD. In this review, we discuss the recent progress in genetics of CHD deciphered by large-scale genome sequencing and explore how genome-edited patient iPSCs are poised to decode the genetic etiologies of CHD by coupling with single-cell genomics and organoid technologies.

Large-scale genome sequencing reveals the driving forces of viruses in microalgal evolution

Being integral primary producers in diverse ecosystems, microalgal genomes could be mined for ecological insights, but representative genome sequences are lacking for many phyla. We cultured and sequenced 107 microalgae species from 11 different phyla indigenous to varied geographies and climates. This collection was used to resolve genomic differences between saltwater and freshwater microalgae. Freshwater species showed domain-centric ontology enrichment for nuclear and nuclear membrane functions, while saltwater species were enriched in organellar and cellular membrane functions. Further, marine species contained significantly more viral families in their genomes (p= 8e-4). Sequences from Chlorovirus, Coccolithovirus, Pandoravirus, Marseillevirus, Tupanvirus, and other viruses were found integrated into the genomes of algal from marine environments. These viral-origin sequences were found to be expressed and code for a wide variety of functions. Together, this study comprehensively defines the expanse of protein-coding and viral elements in microalgal genomes and posits a unified adaptive strategy for algal halotolerance.

Abstract IA33: The immunogenomic landscape of primary prostate cancer in African-American men

Abstract African-American (AA) men have a 1.5-fold higher incidence of prostate cancer (PCa) than non-Latino White (WH) men and are nearly 2.5 times more likely to die from their disease. These disparities are likely due to a combination of social, environmental, and biological factors. Discerning the biological determinants of aggressive PCa in AA men remains a critical and unmet need in cancer health disparities research. Although there have been several large-scale genome sequencing studies that identified unique molecular drivers in primary and metastatic PCa, these have included few AA patients, even fewer with potentially lethal PCa, and have generally lacked clinical outcome data. Work by our group and others demonstrates that the most common somatic genomic alterations in primary PCa (such as ERG rearrangement and PTEN deletion) occur at significantly different frequencies in AA and WH men, providing the first direct evidence for molecular differences between PCa arising in AA and WH patients. Similarly, gene expression studies by other groups have consistently found that various immune response pathways are more highly expressed in PCa arising in AA compared to WH patients. However to date, few studies have integrated somatic molecular subtype data with immune tumor microenvironment (TME) characterization across different populations. To begin to address these knowledge gaps, we have studied primary PCa tissues from a unique cohort comprising 200 self-identified AA and 200 WH patients, matched by grade and other clinical-pathologic parameters, with long-term follow-up for biochemical recurrence and metastasis. This cohort is unique in that it is highly enriched for high-risk disease and has now been profiled for somatic genomic, epigenomic, transcriptomic and tumor microenvironment landscapes, enabling one of the first integrative molecular portraits of AA PCa. We find that tumor infiltrating T-lymphocyte density is significantly correlated with underlying tumor molecular subtype and oncologic outcomes, but does not vary by racial ancestry. In contrast, using a combination of transcriptomic, methylation and quantitative immunohistochemical analyses, we demonstrate that tumor infiltrating B-lymphocyte density is significantly higher among AA compared to WH PCa patients, irrespective of molecular subtype, and trends towards improved outcomes. Citation Format: Tamara L. Lotan. The immunogenomic landscape of primary prostate cancer in African-American men [abstract]. In: Proceedings of the AACR Virtual Conference: Thirteenth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2020 Oct 2-4. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(12 Suppl):Abstract nr IA33.

Integration of Protein Interactome Networks With Congenital Heart Disease Variants Reveals Candidate Disease Genes

Congenital heart disease (CHD) is present in 1% of live births, yet identification of causal mutations remains a challenge despite large-scale genomic sequencing efforts. We hypothesized that genetic determinants for CHDs may lie in protein interactomes of GATA4 and TBX5, two transcription factors that cause CHDs. Defining their interactomes in human cardiac progenitors via affinity purification-mass spectrometry and integrating results with genetic data from the Pediatric Cardiac Genomic Consortium revealed an enrichment of de novo variants among proteins that interact with GATA4 or TBX5. A consolidative score that prioritized interactome members based on variant, gene, and proband features identified likely CHD-causing genes, including the epigenetic reader GLYR1. GLYR1 and GATA4 widely co-occupied cardiac developmental genes, resulting in co-activation, and the GLYR1 missense variant associated with CHD disrupted interaction with GATA4. This integrative proteomic and genetic approach provides a framework for prioritizing and interrogating the contribution of genetic variants in disease.

Genome surveying reveals the complete chloroplast genome and nuclear genomic features of the crocin-producing plant Gardenia jasminoides Ellis

Gardenia jasminoides, a well-known traditional Chinese herb, has been extensively utilized for its being as stable pigment in food industry and as rich source of crocin in treatment of various cancers and cardiovascular disease. Nevertheless, molecular data shortage of the organelle and nuclear genome vastly limits further biological research on G. jasminoides. In this study, complete chloroplast (cp) genome and large-scale nuclear genome sequences of G. jasminoides were initially generated by genome survey sequencing, and comprehensive genomic structure and comparison analyses were performed. The results showed that G. jasminoides cp genome displayed a typical quadripartite organization and was sized in 154,921 bp with 37.5% GC content. It contained 132 genes, 18 out of which were duplicated in the inverted repeat regions (IRs). Fifty long repeats (motif > 10 bp) and 27 simple sequence repeats were detected, and 30 usage-biased codons and 58 RNA-editing sites were predicted in G. jasminoides cp genome. The G. jasminoides cp genome was similar to those related species in Rubiaceae in terms of gene order and IR borders and a sister relationship of Gardenia and Coffea is strongly supported. Furthermore, the nuclear genome size of G. jasminoides was estimated to be 562.9 Mb, with heterozygosity rate being of 0.68%, repeat proportion of 51.6% and GC content of 36.44%. Overall, the data resources and findings generated in the present study will shed new light on the molecular and breeding studies on this important crocin-producing plant in the future.

Genetic profiling of Vietnamese population from large-scale genomic analysis of non-invasive prenatal testing data

The under-representation of several ethnic groups in existing genetic databases and studies have undermined our understanding of the genetic variations and associated traits or diseases in many populations. Cost and technology limitations remain the challenges in performing large-scale genome sequencing projects in many developing countries, including Vietnam. As one of the most rapidly adopted genetic tests, non-invasive prenatal testing (NIPT) data offers an alternative untapped resource for genetic studies. Here we performed a large-scale genomic analysis of 2683 pregnant Vietnamese women using their NIPT data and identified a comprehensive set of 8,054,515 single-nucleotide polymorphisms, among which 8.2% were new to the Vietnamese population. Our study also revealed 24,487 disease-associated genetic variants and their allele frequency distribution, especially 5 pathogenic variants for prevalent genetic disorders in Vietnam. We also observed major discrepancies in the allele frequency distribution of disease-associated genetic variants between the Vietnamese and other populations, thus highlighting a need for genome-wide association studies dedicated to the Vietnamese population. The resulted database of Vietnamese genetic variants, their allele frequency distribution, and their associated diseases presents a valuable resource for future genetic studies.

Large-scale genome sequencing of mycorrhizal fungi provides insights into the early evolution of symbiotic traits

Mycorrhizal fungi are mutualists that play crucial roles in nutrient acquisition in terrestrial ecosystems. Mycorrhizal symbioses arose repeatedly across multiple lineages of Mucoromycotina, Ascomycota, and Basidiomycota. Considerable variation exists in the capacity of mycorrhizal fungi to acquire carbon from soil organic matter. Here, we present a combined analysis of 135 fungal genomes from 73 saprotrophic, endophytic and pathogenic species, and 62 mycorrhizal species, including 29 new mycorrhizal genomes. This study samples ecologically dominant fungal guilds for which there were previously no symbiotic genomes available, including ectomycorrhizal Russulales, Thelephorales and Cantharellales. Our analyses show that transitions from saprotrophy to symbiosis involve (1) widespread losses of degrading enzymes acting on lignin and cellulose, (2) co-option of genes present in saprotrophic ancestors to fulfill new symbiotic functions, (3) diversification of novel, lineage-specific symbiosis-induced genes, (4) proliferation of transposable elements and (5) divergent genetic innovations underlying the convergent origins of the ectomycorrhizal guild.

Establishment and Verification of An Efficient Virus-induced Gene Silencing System in Forsythia

To understand the functional identification of large-scale genomic sequences in Forsythia, tobacco rattle virus (TRV)-mediated virus-induced gene silencing (VIGS), suitable for the plant, was explored in this study. The results showed that the TRV-mediated VIGS system could be successfully used in Forsythia for silencing the reporter gene FsPDS (Forsythia phytoene desaturase) using stem infiltration and leaf infiltration methods. All the treated plants were pruned below the injection site after 7–15 d infection; the FsPDS was silenced and typical photobleaching symptoms were observed in newly sprouted leaves at the whole-plant level. Meanwhile, this system has been successfully tested and verified through virus detection and qRT-PCR analysis. After the optimization, Forsythia magnesium chelatase subunit H (FsChlH) was silenced successfully in Forsythia using this system, resulting in yellow leaves with decreased chlorophyll content. The system was stable, highly efficient and had greater rapidity and convenience, which made it suitable to study the function of genes related to physiological pathways such as growth and development, and metabolic regulation in Forsythia.