TGM2 and obesity due to melanocortin 4 receptor deficiency: To determine the source of AT TGM2 in HFD-induced obesity, a secondary analysis of snRNAseq eWAT published data by Sarvari et al.34, showed an increased abundance of Tgm2 expressing cells belonging to the immune cell fraction in HFD mice compared to CD group (Fig. 1D).