Further, antisense oligonucleotide-mediated knockdown, or genetic deletion of the TMAO-producing enzyme, flavin-containing monooxygenase 3 (FMO3), offers protection against hyperglycemia, hepatic insulin resistance, and obesity in mice (Schugar et al., 2017). The gene discussed is FMO3; the disease is obesity due to melanocortin 4 receptor deficiency.