show Abstracthide AbstractRecent evidence from high-resolution molecular studies suggests links between microbial dysbiosis in the gastrointestinal tract and a number of complex chronic diseases including diabetes mellitus. The present study forms a pilot study for the larger Luxembourg-based Diabetes Multiplex Family Study (MUST). Within the pilot study, we investigate the interplay of the gastrointestinal microbiota, lifestyle and genetic background in an observational study of families with two or more individuals affected by type 1 diabetes mellitus. Faecal samples which have undergone comprehensive biomolecular extractions are currently analysed using a multi-omics approach. Anthropometric data, including demographics, medical history, health status, medication, and dietary habits of all study participants were collected and are integrated with molecular data.