Fig. 2

Box plot of CpG methylation in peripheral whole blood for the BACH2 and MGAT3 genes in the Edinburgh and Florence cohorts and in B cells from a subset of patients from Edinburgh cohort. Groups were compared using the Mann-Whitney U test with significance threshold of p = 0.05, corrected for multiple testing using the Bonferroni method. a Methylation levels were generally low in the assayed portion of the BACH2 gene promoter, with significant differences between HC and CD methylation at CpG sites 4, 5, 6, and 8 (replicated in both cohorts). For the MGAT3 gene, general methylation level was high, with all CpG sites showing a reproducibly significant difference between HC and both CD and UC, except for CpG sites 2, 13, and 15 for which reproducible significant differences were found only between HC and CD. b In B cells, isolated from PBMCs of a subset of the patients from the Edinburg cohort, differential methylation was found at the CpG position 5 of the BACH2 gene (assay 2) between HC and CD, while for the MGAT3 gene, differentially methylated were CpG sites 1–5, 12, and 13 between HC and CD. CD Crohn’s disease, UC ulcerative colitis, HC healthy controls