While some studies of adults with nonalcoholic steatohepatitis, a common obesity-related fibro-inflammatory disease of the liver, show altered transport by organic anion transporting polypeptide (OATP) and multidrug resistance-associated protein (MRP), such investigations have yet to be explored in adults or children with obesity specifically (Pierre et al., 2017; Ali et al., 2018; Sjöstedt et al., 2021). The gene discussed is ABCC3; the disease is obesity due to melanocortin 4 receptor deficiency.