Interestingly, when studying the correlations by classifying patients according to disease activity, it was observed that in the low-activity group, there was no correlation between claudin-1 and any taxa, while in the high-activity patients, the correlation with Veillonella and an unknown genus of the family Lachnospiraceae reported to associate with inflammatory bowel disease [65]. The gene discussed is CLDN1; the disease is inflammatory bowel disease.