To investigate the molecular and cellular signature of aortic ECs that lack ATGL during the early stages of atherosclerosis progression, single-cell RNA-Seq (scRNA-Seq) was performed on cells isolated from aortas of control plus mPcsk9 and Atgl ECKO plus mPcsk9 mice after 4 weeks of atherogenic diet feeding (n = 4/group). The gene discussed is PNPLA2; the disease is atherosclerosis.