On the contrary, adipose tissue-specific deletion of SIRT6 sensitized mice to HFD obesity and led to a decreased adipose triglyceride lipase (ATGL) levels due to acetylation changes on its transcriptional regulator, FOXO1 in the SIRT6 KO mice [133]. The gene discussed is SIRT6; the disease is obesity due to melanocortin 4 receptor deficiency.