INS and obesity due to melanocortin 4 receptor deficiency: Consistent with a less pronounced obesity-associated microbial signature, wild-type mice receiving fecal microbiota of Acod1-/- littermates gained less weight (Fig. 6A), showed lower fat depots and liver weights (Fig. 6B) as well as increased insulin sensitivity (Fig. 6C and Supplementary Fig. 11A), compared with wild type donors.