Fig. 1

Association of serum ferritin with liver fat accumulation, gene richness and the gut microbiome composition. Association of serum ferritin with degree of liver fat accumulation in a the discovery and b replication cohorts (Mann-Kendall trend test and Wilcoxon tests). c Association of hs-CRP with serum ferritin quartiles in the replication cohort (Mann-Kendall trend test and Wilcoxon tests). d Association of microbial gene richness with ferritin quartiles in a subsample of obese women from the discovery and replication cohorts (generalized linear model GLM). e Bacterial families and f genera associated with serum ferritin in a subsample of obese women from the discovery and replication cohorts. Mnet penalized regression models were built on bacterial data including age, BMI, country and hs-CRP as covariates. g Volcano plot of differential bacterial abundance and h metagenome KEGG functions associated with ferritin as calculated from shotgun metagenomic sequencing in an independent cohort of obese and non-obese subjects, adjusting for age, BMI, sex and hs-CRP. Significantly different taxa are coloured according to phylum. adaB, methylated-DNA-[protein]-cysteine S-methyltransferase; cpg; glutamate carboxypeptidase; cycA; d-serine/d-alanine/glycine transporter; fabA, 3-hydroxyacyl-[acyl-carrier protein] dehydratase/trans-2-decenoyl-[acyl-carrier protein] isomerase; fabM; trans-2-decenoyl-[acyl-carrier protein] isomerase; gshA, glutamate-cysteine ligase; nei endonuclease VIII; entF, enterobactin synthetase component F; FTR, FTH1, efeU, high-affinity iron transporter; hemG; menaquinone-dependent protoporphyrinogen oxidase; hutM, histidine permease; mtsC; iron/zinc/manganese/copper transport system permease protein; mtsA; iron/zinc/manganese/copper transport system substrate-binding protein; PARP, poly [ADP-ribose] polymerase; seqA; negative modulator of initiation of replication; yqjH, ferric-chelate reductase (NADPH)