ETV4, a member of the PEA3 subgroup of the ETS transcription factor family,26 plays important roles in regulating gene expression during early embryogenesis,27 obesity, and diabetes,28 as well as oncogenesis,29,30 and its overexpression is involved in the malignant transformation of cells and enhanced tumor cell invasion.31 Here, ETV4 is linked to obesity due to melanocortin 4 receptor deficiency.