Eubacterium ventriosum has been associated with obesity,26,27 while butyrate-producing organisms such as Butyricicoccus appear to cause shifts in fermentation patterns which affect energy homeostasis.27 Our work identified this cluster as being associated with higher weight, higher insulin resistance, higher fasting blood glucose, and greater systemic inflammation. The gene discussed is INS; the disease is obesity due to melanocortin 4 receptor deficiency.