Project information

The Netherlands X-omics Initiative (X-omics, pronounce as CROSS-omics) is a National Roadmap Large-Scale Research Infrastructure, partially funded by  NWO with a total budget of 40 million euro. The project started September 2018 and will last for 10 years.

X-omics aims to establish a X-omics research infrastructure across the Netherlands, by combining technologies in the field of genomics, proteomics, metabolomics and data analysis, integration & stewardship. With this infrastructure biomedical problems can be solved using an integrated approach (analysis of samples using the available omics technologies of the infrastructure).

Two major goals are:
1. Advance X-omics technologies far beyond state-of-art,
2. Realize an integrated X-omics infrastructure in the Netherlands.

A central helpdesk has been created to provide access to the research infrastructure and enable researchers to use the newest X-omics technologies in their projects. Via this helpdesk researchers can get into contact with X-omics experts for advice on X-omics approaches.

A proof of principle of the X-omics approach will be provided by starting 3 demonstrator projects on different levels (cellular, individual and population).

During the project, training schools will be set up for new ‘omics’ users and for ‘omics’ practitioners.

To allow communications between the users of the infrastructure a X-omics community will be established. This community will interact via meetings, newsletters and social media.

In our brochure you will find information about:

  • The research infrastructure 
  • X-omics equipment and its services 
  • The helpdesk 
  • Training & events 
  • Our X-omics community 

Access to this infrastructure, its available equipment and services is possible for all researchers by contacting the X-omics helpdesk. 


We will demonstrate the added value of our X-omics approach at 3 levels of biomedical research: the cellular, individual and population level.

Examples of research questions that can be addressed are:


  • How does the metabolism of a single cell change during differentiation?
  • How do cells influence each other’s function?
  • How does a cell respond to cancer drugs or become drug resistant?
  • How do dynamic signaling pathways change in time?


  • What changes molecularly when a person gets sick?
  • What molecular features are shared by rare disease patients?
  • How does the molecular system of a person respond to a biological or pharmaceutical challenge?
  • How similar are phenocopies in health/disease at the molecular level?


  • How can we better understand health and disease?
  • How can we better understand the functional consequences of genetic diversity?
  • How do environmental events affect a population’s molecular system?
  • How can we best translate molecular population data to new screening tools?

Data analysis and FAIRification in X-omics – the ACTION demonstrator project

Anna Niehues5, Jenny van Dongen3, XiaoFeng Liao5, Naama Karu4, Alida Kindt4, Casper de Visser5, René Pool3, X-omics/ACTION FAIR and data analysis working group

The data analysis, integration and stewardship pillar of the Netherlands X-omics initiative aims to contribute to the realization of an integrated X-omics infrastructure and to facilitate multi-omics research by providing means for the creation, analysis and integration of FAIR -omics data. In addition to standardization of data and metadata, we envision a FAIR data cube that combines individual -omics data sets or pointers to these data sets with associated linked metadata. The FAIR data cube should provide an interface to query/search rich human- and machine-understandable metadata and extract relevant molecular data for subsequent analysis. Additionally, a ranking algorithm for identifying best matches based on a user-provided query is being considered. This will aid the integration of different types of omics data, and also promote the integration of -omics data from different sources, as well as facilitate submission to relevant data archives. The X-omics/NTR-ACTION demonstrator project is a first use case of our approach toward an integrated workflow combining data FAIRification and reproducible data analysis.

Our data analysis working group investigates the predictive value of multi-omics data for classification of aggressive behavior in children. The NTR-ACTION dataset comprises genomic data (SNP array data on DNA from buccal cells), epigenomic data (Illumina EPIC DNA methylation array data from buccal cells), and biomarker and urine metabolomics data (amines, organic acids, steroidal hormones). Samples were collected from approximately 1300 twins (mean age = 9.7, SD = 1.8, range from 5-13). Data were collected by the Netherlands Twin Register (Ligthart et al. 2019) as part of the ACTION (Aggression in Children: Unraveling gene-environment interplay to inform Treatment and InterventiON strategies) project (Hagenbeek et al 2020, van Dongen et al. 2021), with the goal to identify biomarkers for childhood aggression. Twins were invited for participation in the biomarker study based on their longitudinal data on aggressive behavior at ages 3, 7, and/or 9/10 years. At, or around these ages, parents of twins completed the Achenbach System of Empirically Based Assessment (ASEBA) Child Behavior Checklist (CBCL) and teachers of twins completed the ASEBA Teacher Rating Form (TRF). A design was chosen that selected twin pairs who had either concordant (low-low, high-high) or discordant (low-high) indices of childhood aggression.

For FAIRification of this multi-omics data set, we consider existing standards used in the respective communities of metabolomics and (epi)genomics, as well as requirements by commonly used data archives (e.g. EBI MetaboLights). We make use of the ISA (Investigation, Study, Assay, framework to capture experimental metadata, and re-use and extend the semantic metadata schema developed by the FAIR Genomes project
For our data analysis workflow, we follow recommendations for FAIR software ( and discuss approaches for containerization and workflow management to facilitate reuse with other X-omics partners in the X-omics workflow working group.

The FAIR working group develops the FAIR data cube based on the principle that data should be "as open as possible and as closed as necessary". By incorporating a FAIR Data Point (FDP) component internally, the metadata can be as open as possible and be FAIR-at-the-source. The metadata contents (in our case, ISA metadata) are generated semi-automatically from the data source and exposed to user query in the form of linked metadata (in our case linked ISA). Resources (linked metadata about studies) are publicly accessible by anyone. Administration is needed to create/edit resources. The user control is implemented as part of the FDP. By setting up an access control mechanism between the FDP and the data (i.e., e.g, measured molecular profiles), the data can be as closed as necessary, which enables properly addressing aspects of legislation, privacy, and ethics. The knowledge graph content is generated via existing and newly developed tools. The FAIR Data Cube is an ongoing work hosted on Github (

X-omics/ACTION FAIR and data analysis working group: Fernanda de Andrade1, Jasmin Böhmer2, Jenny van Dongen3, Dorret Boomsma3, Fiona Hagenbeek3, Peter-Bram 't Hoen5, Naama Karu4, Alida Kindt4, Purva Kulkarni5, XiaoFeng Liao5, Leon Mei6, Anna Niehues5, René Pool3, Dieuwke Roelofs-Prins1, Gurnoor Singh5, Morris Swertz1, Joeri van der Velde1, Casper de Visser5, Michael van Vliet4, Gerben van der Vries1

1UMCG, 2UMCU, 3VU, 4LU, 5Radboudumc, 6LUMC

NWO logoThis research was (partially) funded by NWO, project 184.034.019