2. Thus, ATX is a vital enzyme that produces LPA in the blood. As a bioactive lysophospholipid, LPA participates in various cellular processes, including cell survival, proliferation, and migration, via binding to its specific G protein‐coupled receptors (LPAR1 to LPAR6) 3, 4. The majority of the biological functions of ATX are mediated by ATX–LPA signaling. Growing evidence indicates that the ATX–LPA axis is of great significance in many physiological and pathological processes, ranging from inflammatory diseases 5 and obesity 6 to tumorigenesis 7. Here, ENPP2 is linked to obesity due to melanocortin 4 receptor deficiency.