Regulation of transcriptional activity of PPARγ depends not only on the binding of ligands and coactivators but also on its state of phosphorylation which has been explored for the invention of thiazolidinediones as partial agonists with fewer side effects, as the cyclin-dependent kinase 5 phosphorylation of Ser273 residue of PPARγ has a direct influence on development of obesity. The gene discussed is PPARG; the disease is obesity due to melanocortin 4 receptor deficiency.