Genetic insights into FABP polymorphisms linking type 2 diabetes mellitus and non-alcoholic fatty liver disease

Abstract This review finds the genetic interaction between fatty acid-binding protein (FABP) polymorphisms and the role of these polymorphisms in the association between type 2 diabetes mellitus (T2DM) and non-alcoholic fatty liver disease (NAFLD)—two closely related metabolic diseases sharing common pathophysiological mechanisms. Whereas the previous research has independently documented the association of FABP variants with metabolic diseases, this review gives an integrative picture and the combined effect of multiple FABP isoforms (FABP1, FABP2, FABP4, and FABP5) across various metabolic tissues; these include liver, adipose tissue as well as intestine. In particular, this paper integrates the current evidence on the role of FABP polymorphisms in the combined effect on lipid trafficking, insulin resistance, and inflammatory signaling, and thus leads to an overlapping phenotype of T2DM and NAFLD. Also, the review identifies some emerging evidence that supports the connections between the circulating FABP levels and genetic variants, which provides insight into their potential role as biomarkers of metabolic dysfunction. Instead of establishing causality, this work presents a hypothesis-generating framework, which highlights the significance of FABP-mediated pathways in convergence of metabolic diseases. These results justify the necessity of additional multi-marker, multi-omics, and longitudinal studies to confirm the value of FABPs as possible targets in the scope of risk stratification and treatment intervention.