David Molik

Mr. David Molik

orcid

Research Focus & Metrics

Academic Career Length

15Years (2012-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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30 July 2018 in Genome Research
Verified
Journal Article
Open access
PDF file
YHYu-Jui Ho
Yu-Jui Ho
NANaishitha Anaparthy
Naishitha Anaparthy
DMDavid Molik
David Molik
GMGrinu Mathew
Grinu Mathew
TAToby Aicher
Toby Aicher
MHMolly Gale Hammell
Molly Gale Hammell
Single-cell RNA-seq's (scRNA-seq) unprecedented cellular resolution at a genome-wide scale enables us to address questions about cellular heterogeneity that are inaccessible using methods that average over bulk tissue extracts. However, scRNA-seq data sets also present additional challenges such as high transcript dropout rates, stochastic transcription events, and complex population substructures. Here, we present a single-cell RNA-seq analysis and klustering evaluation (SAKE), a robust method for scRNA-seq analysis that provides quantitative statistical metrics at each step of the analysis pipeline. Comparing SAKE to multiple single-cell analysis methods shows that most methods perform similarly across a wide range of cellular contexts, with SAKE outperforming these methods in the case of large complex populations. We next applied the SAKE algorithms to identify drug-resistant cellular populations as human melanoma cells respond to targeted BRAF inhibitors (BRAFi). Single-cell RNA-seq data from both the Fluidigm C1 and 10x Genomics platforms were analyzed with SAKE to dissect this problem at multiple scales. Data from both platforms indicate that BRAF inhibitor-resistant cells can emerge from rare populations already present before drug application, with SAKE identifying both novel and known markers of resistance. These experimentally validated markers of BRAFi resistance share overlap with previous analyses in different melanoma cell lines, demonstrating the generality of these findings and highlighting the utility of single-cell analysis to elucidate mechanisms of BRAFi resistance.

15 January 2025 in Genetics
Verified
Journal Article
Open access
ECEthalinda K S Cannon
Ethalinda K S Cannon
DMDavid Molik
David Molik
AWAdam J Wright
Adam J Wright
HZHuiting Zhang
Huiting Zhang
LHLoren Honaas
Loren Honaas
SDSarah Dyer
Sarah Dyer
The rapid increase in the number of reference-quality genome assemblies presents significant new opportunities for genomic research. However, the absence of standardized naming conventions for genome assemblies and annotations across datasets creates substantial challenges. Inconsistent naming hinders the identification of correct assemblies, complicates the integration of bioinformatics pipelines, and makes it difficult to link assemblies across multiple resources. To address this, we developed a specification for standardizing the naming of reference genome assemblies, to improve consistency across datasets and facilitate interoperability. This specification was created with FAIR (Findable, Accessible, Interoperable, and Reusable) practices in mind, ensuring that reference assemblies are easier to locate, access, and reuse across research communities. Additionally, it has been designed to comply with primary genomic data repositories, including members of the International Nucleotide Sequence Database Collaboration consortium, ensuring compatibility with widely used databases. While initially tailored to the agricultural genomics community, the specification is adaptable for use across different taxa. Widespread adoption of this standardized nomenclature would streamline assembly management, better enable cross-species analyses, and improve the reproducibility of research. It would also enhance natural language processing applications that depend on consistent reference assembly names in genomic literature, promoting greater integration and automated analysis of genomic data. This is a good time to consider more consistent genomic data nomenclature as many research communities and data resources are now finding themselves juggling multiple datasets from multiple data providers.

23 June 2016 in Post Reproductive Health
Verified
Journal Article
Closed access
GCGrant P Cumming
Grant P Cumming
EMEdward Morris
Edward Morris
PSPaul Simpson
Paul Simpson
TFTara French
Tara French
EKEva Kahana
Eva Kahana
DMDavid Molik
David Molik
The World Wide Web celebrated its 25th birthday in 2014. In those 25 years, the Web has evolved from static websites (Web 1.0) to a highly complex dynamic system (Web 3.0) with health information processing one of the primary uses. Until now, the western biomedical paradigm has been effective in delivering healthcare, but this model is not positioned to tackle the complex challenges facing healthcare today. These challenges have arisen by increasing healthcare demands across the world, exacerbated by an ageing population, increased lifespan and chronic conditions. To meet these needs, a ‘biopsychosocial’ shift from reactive to proactive health is necessary with a patient-centric emphasis (personalised, preventative, participatory and predictive) that includes ‘gender-specific medicine’. The management of the menopause, part of post-reproductive health, requires a life-course approach as it provides a framework for achieving a women’s preferred health outcome. Surveys from www.menopausematters.co.uk have consistently shown that women do not feel informed enough to make decisions regarding Hormone Replacement Therapy and alternative therapies. Health professionals must meet this challenge. The recently published National Institute for Health and Care Excellence guidance on the diagnosis and management of the menopause highlights the need for tailored information provision. The Internet underpinned by the academic disciplines of Health Web Science and Medicine 2.0 has potential to facilitate this shift to biopsychosocial medicine and tailored information within a life-course framework. The concept of Health Web Observatories and their potential benefit to a life-course approach using tools such as www.managemymenopause.co.uk is discussed.

27 March 2024 in Briefings in Bioinformatics
Verified
Journal Article
Open access
PDF file
AWAdam Wright
Adam Wright
MWMark D Wilkinson
Mark D Wilkinson
CMChristopher Mungall
Christopher Mungall
SCScott Cain
Scott Cain
SRStephen Richards
Stephen Richards
DMDavid Molik
David Molik
The lack of interoperable data standards among reference genome data-sharing platforms inhibits cross-platform analysis while increasing the risk of data provenance loss. Here, we describe the FAIR bioHeaders Reference genome (FHR), a metadata standard guided by the principles of Findability, Accessibility, Interoperability and Reuse (FAIR) in addition to the principles of Transparency, Responsibility, User focus, Sustainability and Technology. The objective of FHR is to provide an extensive set of data serialisation methods and minimum data field requirements while still maintaining extensibility, flexibility and expressivity in an increasingly decentralised genomic data ecosystem. The effort needed to implement FHR is low; FHR’s design philosophy ensures easy implementation while retaining the benefits gained from recording both machine and human-readable provenance.

12 March 2020 in Methods and Protocols
Verified
Journal Article
Open access
PDF file
DMDavid Molik
David Molik
MPMichael E. Pfrender
Michael E. Pfrender
SEScott J. Emrich
Scott J. Emrich
The advent of next-generation sequencing has allowed for higher-throughput determination of which species live within a specific location. Here we establish that three analysis methods for estimating diversity within samples—namely, Operational Taxonomic Units; the newer Amplicon Sequence Variants; and a method commonly found in sequence analysis, minhash—are affected by various properties of these sequence data. Using simulations we show that the presence of Single Nucleotide Polymorphisms and the depth of coverage from each species affect the correlations between these approaches. Through this analysis, we provide insights which would affect the decisions on the application of each method. Specifically, the presence of sequence read errors and variability in sequence read coverage deferentially affects these processing methods.

7 April 2021 in PLOS Neglected Tropical Diseases
Verified
Journal Article
Open access
PDF file
DMDavid Molik
David Molik
DTDeAndre Tomlinson
DeAndre Tomlinson
SDShane Davitt
Shane Davitt
EMEric L. Morgan
Eric L. Morgan
MSMatthew Sisk
Matthew Sisk
MPMichael E. Pfrender
Michael E. Pfrender
Cryptococcus neoformans is responsible for life-threatening infections that primarily affect immunocompromised individuals and has an estimated worldwide burden of 220,000 new cases each year—with 180,000 resulting deaths—mostly in sub-Saharan Africa. Surprisingly, little is known about the ecological niches occupied by C. neoformans in nature. To expand our understanding of the distribution and ecological associations of this pathogen we implement a Natural Language Processing approach to better describe the niche of C. neoformans. We use a Latent Dirichlet Allocation model to de novo topic model sets of metagenetic research articles written about varied subjects which either explicitly mention, inadvertently find, or fail to find C. neoformans. These articles are all linked to NCBI Sequence Read Archive datasets of 18S ribosomal RNA and/or Internal Transcribed Spacer gene-regions. The number of topics was determined based on the model coherence score, and articles were assigned to the created topics via a Machine Learning approach with a Random Forest algorithm. Our analysis provides support for a previously suggested linkage between C. neoformans and soils associated with decomposing wood. Our approach, using a search of single-locus metagenetic data, gathering papers connected to the datasets, de novo determination of topics, the number of topics, and assignment of articles to the topics, illustrates how such an analysis pipeline can harness large-scale datasets that are published/available but not necessarily fully analyzed, or whose metadata is not harmonized with other studies. Our approach can be applied to a variety of systems to assert potential evidence of environmental associations.