- Ultrarapid Nanopore Genome Sequencing in a Critical Care Setting. The New England journal of medicine 2022
Local read haplotagging enables accurate long-read small variant calling.
bioRxiv : the preprint server for biology
Long-read sequencing technology has enabled variant detection in difficult-to-map regions of the genome and enabled rapid genetic diagnosis in clinical settings. Rapidly evolving third-generation sequencing platforms like Pacific Biosciences (PacBio) and Oxford nanopore technologies (ONT) are introducing newer platforms and data types. It has been demonstrated that variant calling methods based on deep neural networks can use local haplotyping information with long-reads to improve the genotyping accuracy. However, using local haplotype information creates an overhead as variant calling needs to be performed multiple times which ultimately makes it difficult to extend to new data types and platforms as they get introduced. In this work, we have developed a local haplotype approximate method that enables state-of-the-art variant calling performance with multiple sequencing platforms including PacBio Revio system, ONT R10.4 simplex and duplex data. This addition of local haplotype approximation makes DeepVariant a universal variant calling solution for long-read sequencing platforms.
View details for DOI 10.1101/2023.09.07.556731
View details for PubMedID 37745389
View details for PubMedCentralID PMC10515762
APOE loss-of-function variants: Compatible with longevity and associated with resistance to Alzheimer's Disease pathology.
medRxiv : the preprint server for health sciences
The ε4 allele of apolipoprotein E (APOE) is the strongest genetic risk factor for sporadic Alzheimer's Disease (AD). Knockdown of this allele may provide a therapeutic strategy for AD, but the effect of APOE loss-of-function (LoF) on AD pathogenesis is unknown. We searched for APOE LoF variants in a large cohort of older controls and patients with AD and identified six heterozygote carriers of APOE LoF variants. Five carriers were controls (ages 71-90) and one was an AD case with an unremarkable age-at-onset between 75-79. Two APOE ε3/ε4 controls (Subjects 1 and 2) carried a stop-gain affecting the ε4 allele. Subject 1 was cognitively normal at 90+ and had no neuritic plaques at autopsy. Subject 2 was cognitively healthy within the age range 75-79 and underwent lumbar puncture at between ages 75-79 with normal levels of amyloid. The results provide the strongest human genetics evidence yet available suggesting that ε4 drives AD risk through a gain of abnormal function and support knockdown of APOE ε4 or its protein product as a viable therapeutic option.
View details for DOI 10.1101/2023.07.20.23292771
View details for PubMedID 37547016
View details for PubMedCentralID PMC10402217
A 3' UTR Deletion Is a Leading Candidate Causal Variant at the TMEM106B Locus Reducing Risk for FTLD-TDP.
medRxiv : the preprint server for health sciences
Single nucleotide variants (SNVs) near TMEM106B have been associated with risk of frontotemporal lobar dementia with TDP pathology (FTLD-TDP) but the causal variant at this locus has not yet been isolated. The initial leading FTLD-TDP genome-wide association study (GWAS) hit at this locus, rs1990622, is intergenic and is in linkage disequilibrium (LD) with a TMEM106B coding SNV, rs3173615. We developed a long-read sequencing (LRS) dataset of 407 individuals in order to identify structural variants associated with neurodegenerative disorders. We identified a prevalent 322 base pair deletion on the TMEM106B 3' untranslated region (UTR) that was in perfect linkage with rs1990622 and near-perfect linkage with rs3173615 (genotype discordance in two of 274 individuals who had LRS and short-read next-generation sequencing). In Alzheimer's Disease Sequencing Project (ADSP) participants, this deletion was in greater LD with rs1990622 (R2=0.920916, D'=0.963472) than with rs3173615 (R2=0.883776, D'=0.963575). rs1990622 and rs3173615 are less closely linked (R2=0.7403, D'=0.9915) in African populations. Among African ancestry individuals in the ADSP, the deletion is in even greater LD with rs1990622 (R2=0.936841, D'=0.976782) than with rs3173615 (R2=0.764242, D'=0.974406). Querying publicly available genetic datasets with associated mRNA expression and protein levels, we confirmed that rs1990622 is consistently a protein quantitative trait locus but not an expression quantitative trait locus, consistent with a causal variant present on the TMEM106B 3'UTR. In summary, the TMEM106B 3' UTR deletion is a large genetic variant on the TMEM106B transcript that is in higher LD with the leading GWAS hit rs1990622 than rs3173615 and may mediate the protective effect of this locus in neurodegenerative disease.
View details for DOI 10.1101/2023.07.06.23292312
View details for PubMedID 37461476
View details for PubMedCentralID PMC10350161
Deconvoluting complex correlates of COVID-19 severity with a multi-omic pandemic tracking strategy.
2022; 13 (1): 5107
The SARS-CoV-2 pandemic has differentially impacted populations across race and ethnicity. A multi-omic approach represents a powerful tool to examine risk across multi-ancestry genomes. We leverage a pandemic tracking strategy in which we sequence viral and host genomes and transcriptomes from nasopharyngeal swabs of 1049 individuals (736 SARS-CoV-2 positive and 313 SARS-CoV-2 negative) and integrate them with digital phenotypes from electronic health records from a diverse catchment area in Northern California. Genome-wide association disaggregated by admixture mapping reveals novel COVID-19-severity-associated regions containing previously reported markers of neurologic, pulmonary and viral disease susceptibility. Phylodynamic tracking of consensus viral genomes reveals no association with disease severity or inferred ancestry. Summary data from multiomic investigation reveals metagenomic and HLA associations with severe COVID-19. The wealth of data available from residual nasopharyngeal swabs in combination with clinical data abstracted automatically at scale highlights a powerful strategy for pandemic tracking, and reveals distinct epidemiologic, genetic, and biological associations for those at the highest risk.
View details for DOI 10.1038/s41467-022-32397-8
View details for PubMedID 36042219
Accelerated identification of disease-causing variants with ultra-rapid nanopore genome sequencing.
Whole-genome sequencing (WGS) can identify variants that cause genetic disease, but the time required for sequencing and analysis has been a barrier to its use in acutely ill patients. In the present study, we develop an approach for ultra-rapid nanopore WGS that combines an optimized sample preparation protocol, distributing sequencing over 48 flow cells, near real-time base calling and alignment, accelerated variant calling and fast variant filtration for efficient manual review. Application to two example clinical cases identified a candidate variant in <8 h from sample preparation to variant identification. We show that this framework provides accurate variant calls and efficient prioritization, and accelerates diagnostic clinical genome sequencing twofold compared with previous approaches.
View details for DOI 10.1038/s41587-022-01221-5
View details for PubMedID 35347328
- Ultra-Rapid Nanopore Whole Genome Genetic Diagnosis of Dilated Cardiomyopathy in an Adolescent With Cardiogenic Shock. Circulation. Genomic and precision medicine 2022: CIRCGEN121003591
Mapping the human genetic architecture of COVID-19.
The genetic makeup of an individual contributes to susceptibility and response to viral infection. While environmental, clinical and social factors play a role in exposure to SARS-CoV-2 and COVID-19 disease severity1,2, host genetics may also be important. Identifying host-specific genetic factors may reveal biological mechanisms of therapeutic relevance and clarify causal relationships of modifiable environmental risk factors for SARS-CoV-2 infection and outcomes. We formed a global network of researchers to investigate the role of human genetics in SARS-CoV-2 infection and COVID-19 severity. We describe the results of three genome-wide association meta-analyses comprised of up to 49,562 COVID-19 patients from 46 studies across 19 countries. We reported 13 genome-wide significant loci that are associated with SARS-CoV-2 infection or severe manifestations of COVID-19. Several of these loci correspond to previously documented associations to lung or autoimmune and inflammatory diseases3-7. They also represent potentially actionable mechanisms in response to infection. Mendelian Randomization analyses support a causal role for smoking and body mass index for severe COVID-19 although not for type II diabetes. The identification of novel host genetic factors associated with COVID-19, with unprecedented speed, was made possible by the community of human genetic researchers coming together to prioritize sharing of data, results, resources and analytical frameworks. This working model of international collaboration underscores what is possible for future genetic discoveries in emerging pandemics, or indeed for any complex human disease.
View details for DOI 10.1038/s41586-021-03767-x
View details for PubMedID 34237774
High-throughput SARS-CoV-2 and host genome sequencing from single nasopharyngeal swabs.
medRxiv : the preprint server for health sciences
During COVID19 and other viral pandemics, rapid generation of host and pathogen genomic data is critical to tracking infection and informing therapies. There is an urgent need for efficient approaches to this data generation at scale. We have developed a scalable, high throughput approach to generate high fidelity low pass whole genome and HLA sequencing, viral genomes, and representation of human transcriptome from single nasopharyngeal swabs of COVID19 patients.
View details for DOI 10.1101/2020.07.27.20163147
View details for PubMedID 32766602
View details for PubMedCentralID PMC7402057
Raltegravir Is a Potent Inhibitor of XMRV, a Virus Implicated in Prostate Cancer and Chronic Fatigue Syndrome
2010; 5 (3): e9948
Xenotropic murine leukemia-related retrovirus (XMRV) is a recently discovered retrovirus that has been linked to human prostate cancer and chronic fatigue syndrome (CFS). Both diseases affect a large fraction of the world population, with prostate cancer affecting one in six men, and CFS affecting an estimated 0.4 to 1% of the population.Forty-five compounds, including twenty-eight drugs approved for use in humans, were evaluated against XMRV replication in vitro. We found that the retroviral integrase inhibitor, raltegravir, was potent and selective against XMRV at submicromolar concentrations, in MCF-7 and LNCaP cells, a breast cancer and prostate cancer cell line, respectively. Another integrase inhibitor, L-000870812, and two nucleoside reverse transcriptase inhibitors, zidovudine (ZDV), and tenofovir disoproxil fumarate (TDF) also inhibited XMRV replication. When combined, these drugs displayed mostly synergistic effects against this virus, suggesting that combination therapy may delay or prevent the selection of resistant viruses.If XMRV proves to be a causal factor in prostate cancer or CFS, these discoveries may allow for rational design of clinical trials.
View details for DOI 10.1371/journal.pone.0009948
View details for Web of Science ID 000276418200024
View details for PubMedID 20376347
View details for PubMedCentralID PMC2848589