The NIHR IBD Bioresource comprises ~34k participants with Inflammatory Bowel Disease (IBD). The NIHR IBD BioResource extracts DNA from blood and saliva samples taken at recruitment, and measures a panel of SNPs on each DNA sample, using a commodity SNP genotyping array from e.g. Illumina or Affymetrix (now Thermofisher). This is used to pre-screen or match participants when inviting them to take part in experimental medicine studies. De-identified versions of this data is available to researchers investigating the feasibility of future studies. The Technical Metadata describes a SNP annotation file – i.e. what the chip is measuring. The file itself has as many rows as there are SNPs represented on the chip, and is proprietary to the manufacturer, although deeply familiar to researchers.