No genes relating to lipid metabolism were identified as differentially expressed between HCV gt1 and gt3 infection, and only one gene related to lipid signalling was identified – free fatty acid receptor 2 (FFAR2; up-regulated 2.2-fold in HCV gt1 infection; Table S2), a G-protein-coupled receptor, expressed on leucocytes, that recognizes short-chain free fatty acids [19]. The gene discussed is FFAR2; the disease is infection.