Some studies have shown that P. copri were involved in occurrence of obesity (Stanislawski et al., 2019) through promoting the biosynthesis of branched-chain amino acids to induce insulin resistance (Pedersen et al., 2016) and stimulating the secretion of inflammatory factors to trigger or aggravate the host’s inflammatory response (Larsen, 2017). The gene discussed is INS; the disease is obesity due to melanocortin 4 receptor deficiency.