Besides the intensively studied role of PDE10A in various brain disorders, we have shown that this enzyme is highly expressed in the brown adipose tissue by a retrospective analysis of human [18F]30 PET data and using our PDE10A-specific radioligand [18F]34 ([18F]AQ28A) in different mouse models of obesity [175,176]. The gene discussed is PDE10A; the disease is obesity due to melanocortin 4 receptor deficiency.