Your domain: Human pathogen genomics

Introduction

The human pathogen genomics domain focuses on studying the genetic code of organisms that cause disease in humans. Studies to identify and understand pathogens are conducted across different types of organisations ranging from research institutes to regional public health authorities. The aims can include urgent outbreak response, prevention measures, and developing remedies such as treatments and vaccines.

Data management challenges in this domain include the potential urgency of data sharing and secondary use of data across initiatives emerging from research, public health and policy. While the pathogenic organisms are the object of interest, there are many considerations to account for when dealing with samples collected from patients, pathogen surveillance, and human research subjects.

The genomic data can represent anything from the genetic sequence of a single pathogen isolate to various fragments of genetic materials from a flora of pathogens in larger population. Other data can represent a wide range of contextual information about the human host, the disease, and various environmental factors.

Planning a study with pathogen genomic data

Description

While the object of interest in this domain are pathogens, the data is usually derived from samples originating from patients and human research subjects. This means that you must plan to either remove or to handle human data during your study.

Considerations

What legal and ethical aspects do you need to consider?
- Can you separate pathogen and human host material and data?
- What data protection measures should be implemented in contracts and procedures dealing with suppliers and collaborators?
- What is the appropriate scope for the legal and ethical agreements necessary for the study?
- How should statements related to data processing be phrased to allow timely and efficient data sharing?
- How much time would be required to negotiate access to the samples and data for the study?
What public health and research initives should you consider aligning with?
- What data could be shared with or reused from other initiatives during the project?
- How will you align your practices with these initiatives to maximise the impact of the data and insight generated by the project?
- How will you share data with your collaborators and other initiatives?
What conventions will you adopt when planning your study?
- What existing protocols should you consider adopting for sample preparation, sequencing, variant calling etc?
- What conventions should you adopt for documenting your research?

Solutions

Working with human data

Ensure that the project’s procedures conform with good practices for handling human data. In particular, the following sections of the RDMkit:
- Planning for projects with human data
- Processing and analysing human data

Isolate pathogen from host information

Depending on the pathogen, how it interacts with the host, or the methods applied, it can be possible to generate clean isolates that do not contain host related material. Data produced from a clean isolate could potentially be handled with few restrictions, while other data will be considered to be personal and sensitive that need protection.

Public health initiatives

National and international recommendations from public health authorities, epidemic surveillance programs and research data communities should be considered when planning a new study or surveillance programme. In particular, you could consult conventions for relevant surveillance programs while considering widely adopted guidelines for research documentation, and instructions from the data sharing platforms.
- European Centre for Disease Prevention and Control (ECDC) coordinates Disease and laboratory networks and also issues Surveillance and reporting protocols and other Technical guidance on sequencing.
- WHO genomic surveillance strategy and guidance on implementation for maximum impact on public health and there are published reports that advise on Implementing Quality Management Systems in Public Health Laboratories.
- The US Centers for Disease Control and Prevention (CDC) offers guidance on Pathogen genomics for its work in monitoring, investigating, and controlling infectious diseases.
- Refer to National resources for information on regional authorities and national considerations.

Sequencing experiments

Good practices for genome experiments suggest that the documentation, at a minimum, should describe the design of the study or surveillance program, the collected specimens and how the samples were prepared, the experimental setup and protocols, and the analysis workflow.
- Adopt recommendations specifically for genomics and pathogen genomics such as Ten simple rules for annotating sequencing experiments.
- Refer to general guidance on how to provide documentation and metadata during your project.
Adopt standards, conventions and robust protocols to maximise the reuse potential of the data in parallel initiatives and your future projects.
- The Genomic Standards Consortium (GSC) develops and maintains the GSC Minimum Information about any Sequence (MIxS) set of core and extended descriptors for genomes and metagenomes with associated samples and their environment to guide scientists on how to capture the metadata essential for high quality research.
- The GenEpiO Consortium develops and maintains the Genomic Epidemiology Application Ontology (GenEpiO) to support data sharing and integration specifically for foodborne infectious disease surveillance and outbreak investigations.
- The Public Health Alliance for Genomic Epidemiology (PHA4GE) supports openness and interoperability in public health bioinformatics. The Data Structures working group develops, adapts and standardises data models for microbial sequence data, contextual metadata, results and workflow metrics, such as the SARS-CoV-2 contextual data specification.
- ISO (the International Organization for Standardization) has issued standards that can be referenced when designing or commissioning genomic sequencing and informatics services, such as

Collecting and processing pathogen genomic data

Considerations

What information should you consider recording when collecting data?
- What should you note when collecting, storing and preparing the samples?
- How will you capture information about the configuration and quality of the sequencing results?
- How will you ensure that the information captured is complete and correct?
What data and file formats should you consider for your project?
- What are the de-facto standards used for the experiment type and down-stream analysis-pipelines?
- Where are the instrument specific aspects for the data and files formats documented?
What existing data will you integrate or use as a reference in your project?
- What reference genome(s) will you need access to?
- What is the recommended citation for the data and their versions?

Solutions

Filtering genomic reads corresponding to human DNA fragments

Data files with reads produced by sequencing experiments sometimes contain fragments of the host organism’s DNA. When the host is a human research subject or patient, these fragments can be masked or removed to produce files that could potentially be handled with fewer restrictions. The approach chosen to mask the host associated reads leads to different trade-offs. Make sure to include this as a factor in your risk assessment.
- Mapping to (human) host reference genomes, can inadvertently leave some host associated reads unmasked.
- Mapping to pathogens reference genomes can inadvertently mask some pathogen associated reads and still leave some host associated reads unmasked
- Removal of human reads from SARS-CoV-2 sequencing data | Galaxy training

Contextual information about the sample

Information about the host phenotype, context and disease is often necessary to answer questions in a research study or policy perspective. Other contextual information can include non-host related environmental factors, such as interactions with other pathogens, drugs and geographic proliferation. It can also include information about the sampled material and how it was processed for sequencing.
Adopt common reporting checklists, data dictionaries, terms and vocabularies to simplify data sharing across initiatives.
- ENA hosts a selection of sample checklists that can be used to annotate sequencing experiements, including checklists derived from the MIxS consortium. The ENA virus pathogen reporting standard checklist has been widely used for SARS-CoV-2 genomic studies.
- Reuse terms and definitions from existing vocabularies, such as the Phenotypic QualiTy Ontology, NCBI Taxonomy, Disease Ontology, Chemical Entities of Biological Interest, and UBER anatomy ONtology.
- The PHA4GE SARS-CoV-2 contextual data specification is a comprehensive example including a reporting checklist, related protocols, and mappings to relevant vocabularies and data sharing platforms.

Generating genomic data

Establish protocols and document the steps taken in the lab to process the sample and in the computational workflow to prepare the resulting data. Make sure to keep information from quality assurance procedures and strive to make your labwork and computational process as reproducible as possible.
- High-Throughput Sequencing | LifeScienceRDMLookUp
- The Beyond One Million Genomes (B1MG) project provides guidelines that cover the minimum quality requirements for the generation of genome sequencing data.
- Data repositories generally have information about recommended data file formats and metadata
- The FAIR Cookbook provides instructions on validation of file formats
- A good place to look for scientific and technical information about data quality validation software tools for pathogenomics is Bio.Tools.
- The Infectious Diseases Toolkit (IDTk) has a showcase on An automated SARS-CoV-2 genome surveillance system built around Galaxy
- The Galaxy Training Network provides free on-line training materials on quality control.

Considerations

What data need to be preserved by the project and for how long?
What is preserved by others and how would someone find and access the data?
What databases should I use to share human pathogen genomics data?
What other research information (such as protocols, computational tools, samples) can the project share?

Solutions

Some host related information can be personal and/or sensitive and care should be taken when storing and sharing it. Apply data masking and aggregation techniques to pseudonymise or anonymise the contextual information and take measures to separate personal and sensitive information from the pathogen data when possible.
Adopt solutions for federated analysis to support distributed analyses on information that could otherwise not be shared, such as establishing contractual agreements with suitable regional or international data infrastructures.
GA4GH (Global Alliance for Genomics and Health) is a global organisation that frames policy and builds standards to meet the real-world needs of the genomics and health community. Its GDPR & International Health Data Sharing Forum shares GDPR Briefs that represent a consensus position among its Forum Members (not legal advice) regarding the current understanding of the GDPR and its implications for genomic and health-related research, such as
- GDPR Brief: data protection implications of publishing metadata to enable discovery
- GDPR Brief: federated analysis for responsible data sharing under the GDPR

You should adopt good practices for data sharing and identify which data sharing platforms to use to reach the relevant stakeholders. You can use more than one platform but care should be taken to make sure that data is interconnected where possible to enable deduplication in downstream analyses.
- European healthcare surveillance systems is administered and used by public health authorities such as ECDC’s TESSy/EpiPulse
- International research data exchanges such as European Nucleotide Archive (ENA) for non-sensitive genomic data and the Federated EGA network for sensitive data.
- There are also pathogen specifc initiatives, such as EMBL-EBI Pathogens and NCBI Pathogen Detection. And initiatives focusing specifically on viruses, certain pathogens or certain data types, such as GISAID (Global Initiative on Sharing All Influenza Data) for observations and assembled consensus sequences on a selection of pathogens.
Investigate if there are national resources or a data brokering organisation available to facilitate data sharing.
- EBI Pathogens data hubs
- Submit new data | European COVID-19 platform