FTO and obesity due to melanocortin 4 receptor deficiency: The FTO gene has been found to play a key role in the development of NAFLD in several existing studies, and in a GWAS, study the FTO gene had a positive causal effect on obesity and blood glucose levels, which is in line with the major pathways of action of FTO in NAFLD revealed in our transcriptome enrichment analysis (Chen, Du, et al. 2023; Mizuno 2018).