Long-chain FFAs are ligands for the FFA1 receptor (also known as GPR40) and FFA4 receptor (also known as GPR120), which indirectly affect energy homeostasis via hormonal signaling, thus, linking FAs and diet with metabolic disorders and type 2 diabetes (T2D) [5,6]. The gene discussed is FFAR1; the disease is type 2 diabetes mellitus.