Comparison of Small Gut and Whole Gut Microbiota of First-Degree Relatives with Adult Patients with Celiac Disease and Controls

Objectives: Gut microbiota gets altered in patients with celiac disease (CeD), whether the changes in gut microbiota are cause or the effect of the disease is not well known. The first degree relatives (FDRs) of CeD are genetically susceptible and may represent a pre-diseased state. Therefore, understanding differences in duodenal and faecal microibiota between the FDR and CeD subject is of interest. To investigate this, we characterised the microbiota in duodenal biopsies and faeces of CeD patients (n = 23), FDRs (n = 15) and controls (n= 24) subjects by 16S rRNA gene sequencing approach. Results: At microbial community level, duodenal biopsies showed more diverse pattern than faecal samples. Several OTUs were differentially abundant in study groups, both in duodenal biopsies and faecal samples. At OTU level, in duodenal biopsies, 52 OTUs were differentially abundant between FDR and DC group and 41 OTUs between FDR and CeD (P